Merge branch 'integration' into memory_api

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

.ai/instructions.md

@@ -186,6 +186,11 @@ This document provides essential context for AI models interacting with this pro
         └── components/[component]/ # Component-specific tests
         ```
         Run them using `script/test_build_components`. Use `-c <component>` to test specific components and `-t <target>` for specific platforms.
+    *   **Testing All Components Together:** To verify that all components can be tested together without ID conflicts or configuration issues, use:
+        ```bash
+        ./script/test_component_grouping.py -e config --all
+        ```
+        This tests all components in a single build to catch conflicts that might not appear when testing components individually. Use `-e config` for fast configuration validation, or `-e compile` for full compilation testing.
 *   **Debugging and Troubleshooting:**
     *   **Debug Tools:**
         - `esphome config <file>.yaml` to validate configuration.

.clang-tidy.hash

@@ -1 +1 @@
-ab49c22900dd39c004623e450a1076b111d6741f31967a637ab6e0e3dd2e753e
+049d60eed541730efaa4c0dc5d337b4287bf29b6daa350b5dfc1f23915f1c52f

.github/workflows/ci.yml

@@ -177,6 +177,7 @@ jobs:
       clang-tidy: ${{ steps.determine.outputs.clang-tidy }}
       python-linters: ${{ steps.determine.outputs.python-linters }}
       changed-components: ${{ steps.determine.outputs.changed-components }}
+      changed-components-with-tests: ${{ steps.determine.outputs.changed-components-with-tests }}
       component-test-count: ${{ steps.determine.outputs.component-test-count }}
     steps:
       - name: Check out code from GitHub
@@ -204,6 +205,7 @@ jobs:
           echo "clang-tidy=$(echo "$output" | jq -r '.clang_tidy')" >> $GITHUB_OUTPUT
           echo "python-linters=$(echo "$output" | jq -r '.python_linters')" >> $GITHUB_OUTPUT
           echo "changed-components=$(echo "$output" | jq -c '.changed_components')" >> $GITHUB_OUTPUT
+          echo "changed-components-with-tests=$(echo "$output" | jq -c '.changed_components_with_tests')" >> $GITHUB_OUTPUT
           echo "component-test-count=$(echo "$output" | jq -r '.component_test_count')" >> $GITHUB_OUTPUT
 
   integration-tests:
@@ -367,12 +369,13 @@ jobs:
       fail-fast: false
       max-parallel: 2
       matrix:
-        file: ${{ fromJson(needs.determine-jobs.outputs.changed-components) }}
+        file: ${{ fromJson(needs.determine-jobs.outputs.changed-components-with-tests) }}
     steps:
-      - name: Install dependencies
-        run: |
-          sudo apt-get update
-          sudo apt-get install libsdl2-dev
+      - name: Cache apt packages
+        uses: awalsh128/cache-apt-pkgs-action@acb598e5ddbc6f68a970c5da0688d2f3a9f04d05 # v1.5.3
+        with:
+          packages: libsdl2-dev
+          version: 1.0
 
       - name: Check out code from GitHub
         uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
@@ -381,17 +384,17 @@ jobs:
         with:
           python-version: ${{ env.DEFAULT_PYTHON }}
           cache-key: ${{ needs.common.outputs.cache-key }}
-      - name: test_build_components -e config -c ${{ matrix.file }}
+      - name: Validate config for ${{ matrix.file }}
         run: |
           . venv/bin/activate
-          ./script/test_build_components -e config -c ${{ matrix.file }}
-      - name: test_build_components -e compile -c ${{ matrix.file }}
+          python3 script/test_build_components.py -e config -c ${{ matrix.file }}
+      - name: Compile config for ${{ matrix.file }}
         run: |
           . venv/bin/activate
-          ./script/test_build_components -e compile -c ${{ matrix.file }}
+          python3 script/test_build_components.py -e compile -c ${{ matrix.file }}
 
   test-build-components-splitter:
-    name: Split components for testing into 20 groups maximum
+    name: Split components for intelligent grouping (40 weighted per batch)
     runs-on: ubuntu-24.04
     needs:
       - common
@@ -402,14 +405,26 @@ jobs:
     steps:
       - name: Check out code from GitHub
         uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
-      - name: Split components into 20 groups
+      - name: Restore Python
+        uses: ./.github/actions/restore-python
+        with:
+          python-version: ${{ env.DEFAULT_PYTHON }}
+          cache-key: ${{ needs.common.outputs.cache-key }}
+      - name: Split components intelligently based on bus configurations
         id: split
         run: |
-          components=$(echo '${{ needs.determine-jobs.outputs.changed-components }}' | jq -c '.[]' | shuf | jq -s -c '[_nwise(20) | join(" ")]')
-          echo "components=$components" >> $GITHUB_OUTPUT
+          . venv/bin/activate
+
+          # Use intelligent splitter that groups components with same bus configs
+          components='${{ needs.determine-jobs.outputs.changed-components-with-tests }}'
+
+          echo "Splitting components intelligently..."
+          output=$(python3 script/split_components_for_ci.py --components "$components" --batch-size 40 --output github)
+
+          echo "$output" >> $GITHUB_OUTPUT
 
   test-build-components-split:
-    name: Test split components
+    name: Test components batch (${{ matrix.components }})
     runs-on: ubuntu-24.04
     needs:
       - common
@@ -418,17 +433,23 @@ jobs:
     if: github.event_name == 'pull_request' && fromJSON(needs.determine-jobs.outputs.component-test-count) >= 100
     strategy:
       fail-fast: false
-      max-parallel: 4
+      max-parallel: 5
       matrix:
         components: ${{ fromJson(needs.test-build-components-splitter.outputs.matrix) }}
     steps:
+      - name: Show disk space
+        run: |
+          echo "Available disk space:"
+          df -h
+
       - name: List components
         run: echo ${{ matrix.components }}
 
-      - name: Install dependencies
-        run: |
-          sudo apt-get update
-          sudo apt-get install libsdl2-dev
+      - name: Cache apt packages
+        uses: awalsh128/cache-apt-pkgs-action@acb598e5ddbc6f68a970c5da0688d2f3a9f04d05 # v1.5.3
+        with:
+          packages: libsdl2-dev
+          version: 1.0
 
       - name: Check out code from GitHub
         uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
@@ -437,20 +458,37 @@ jobs:
         with:
           python-version: ${{ env.DEFAULT_PYTHON }}
           cache-key: ${{ needs.common.outputs.cache-key }}
-      - name: Validate config
+      - name: Validate and compile components with intelligent grouping
         run: |
           . venv/bin/activate
-          for component in ${{ matrix.components }}; do
-            ./script/test_build_components -e config -c $component
-          done
-      - name: Compile config
-        run: |
-          . venv/bin/activate
-          mkdir build_cache
-          export PLATFORMIO_BUILD_CACHE_DIR=$PWD/build_cache
-          for component in ${{ matrix.components }}; do
-            ./script/test_build_components -e compile -c $component
-          done
+          # Use /mnt for build files (70GB available vs ~29GB on /)
+          # Bind mount PlatformIO directory to /mnt (tools, packages, build cache all go there)
+          sudo mkdir -p /mnt/platformio
+          sudo chown $USER:$USER /mnt/platformio
+          mkdir -p ~/.platformio
+          sudo mount --bind /mnt/platformio ~/.platformio
+
+          # Bind mount test build directory to /mnt
+          sudo mkdir -p /mnt/test_build_components_build
+          sudo chown $USER:$USER /mnt/test_build_components_build
+          mkdir -p tests/test_build_components/build
+          sudo mount --bind /mnt/test_build_components_build tests/test_build_components/build
+
+          # Convert space-separated components to comma-separated for Python script
+          components_csv=$(echo "${{ matrix.components }}" | tr ' ' ',')
+
+          echo "Testing components: $components_csv"
+          echo ""
+
+          # Run config validation with grouping
+          python3 script/test_build_components.py -e config -c "$components_csv" -f
+
+          echo ""
+          echo "Config validation passed! Starting compilation..."
+          echo ""
+
+          # Run compilation with grouping
+          python3 script/test_build_components.py -e compile -c "$components_csv" -f
 
   pre-commit-ci-lite:
     name: pre-commit.ci lite

.github/workflows/codeql.yml

@@ -58,7 +58,7 @@ jobs:
 
       # Initializes the CodeQL tools for scanning.
       - name: Initialize CodeQL
-        uses: github/codeql-action/init@64d10c13136e1c5bce3e5fbde8d4906eeaafc885 # v3.30.6
+        uses: github/codeql-action/init@f443b600d91635bebf5b0d9ebc620189c0d6fba5 # v4.30.8
         with:
           languages: ${{ matrix.language }}
           build-mode: ${{ matrix.build-mode }}
@@ -86,6 +86,6 @@ jobs:
           exit 1
 
       - name: Perform CodeQL Analysis
-        uses: github/codeql-action/analyze@64d10c13136e1c5bce3e5fbde8d4906eeaafc885 # v3.30.6
+        uses: github/codeql-action/analyze@f443b600d91635bebf5b0d9ebc620189c0d6fba5 # v4.30.8
         with:
           category: "/language:${{matrix.language}}"

.github/workflows/stale.yml

@@ -23,7 +23,7 @@ jobs:
         with:
           debug-only: ${{ github.ref != 'refs/heads/dev' }} # Dry-run when not run on dev branch
           remove-stale-when-updated: true
-          operations-per-run: 150
+          operations-per-run: 400
 
           # The 90 day stale policy for PRs
           # - PRs

.pre-commit-config.yaml

@@ -11,7 +11,7 @@ ci:
 repos:
   - repo: https://github.com/astral-sh/ruff-pre-commit
     # Ruff version.
-    rev: v0.13.3
+    rev: v0.14.0
     hooks:
       # Run the linter.
       - id: ruff

CODEOWNERS

@@ -139,6 +139,7 @@ esphome/components/ens160_base/* @latonita @vincentscode
 esphome/components/ens160_i2c/* @latonita
 esphome/components/ens160_spi/* @latonita
 esphome/components/ens210/* @itn3rd77
+esphome/components/epaper_spi/* @esphome/core
 esphome/components/es7210/* @kahrendt
 esphome/components/es7243e/* @kbx81
 esphome/components/es8156/* @kbx81
@@ -429,6 +430,7 @@ esphome/components/speaker/media_player/* @kahrendt @synesthesiam
 esphome/components/spi/* @clydebarrow @esphome/core
 esphome/components/spi_device/* @clydebarrow
 esphome/components/spi_led_strip/* @clydebarrow
+esphome/components/split_buffer/* @jesserockz
 esphome/components/sprinkler/* @kbx81
 esphome/components/sps30/* @martgras
 esphome/components/ssd1322_base/* @kbx81

Doxyfile

@@ -48,7 +48,7 @@ PROJECT_NAME           = ESPHome
 # could be handy for archiving the generated documentation or if some version
 # control system is used.
 
-PROJECT_NUMBER         = 2025.10.0-dev
+PROJECT_NUMBER         = 2025.11.0-dev
 
 # Using the PROJECT_BRIEF tag one can provide an optional one line description
 # for a project that appears at the top of each page and should give viewer a

esphome/__main__.py

@@ -1009,6 +1009,12 @@ def parse_args(argv):
         action="append",
         default=[],
     )
+    options_parser.add_argument(
+        "--testing-mode",
+        help="Enable testing mode (disables validation checks for grouped component testing)",
+        action="store_true",
+        default=False,
+    )
 
     parser = argparse.ArgumentParser(
         description=f"ESPHome {const.__version__}", parents=[options_parser]
@@ -1278,6 +1284,7 @@ def run_esphome(argv):
 
     args = parse_args(argv)
     CORE.dashboard = args.dashboard
+    CORE.testing_mode = args.testing_mode
 
     # Create address cache from command-line arguments
     CORE.address_cache = AddressCache.from_cli_args(

esphome/components/api/api_frame_helper.h

@@ -19,13 +19,14 @@ namespace esphome::api {
 //#define HELPER_LOG_PACKETS
 
 // Maximum message size limits to prevent OOM on constrained devices
-// Voice Assistant is our largest user at 1024 bytes per audio chunk
-// Using 2048 + 256 bytes overhead = 2304 bytes total to support voice and future needs
-// ESP8266 has very limited RAM and cannot support voice assistant
+// Handshake messages are limited to a small size for security
+static constexpr uint16_t MAX_HANDSHAKE_SIZE = 128;
+
+// Data message limits vary by platform based on available memory
 #ifdef USE_ESP8266
-static constexpr uint16_t MAX_MESSAGE_SIZE = 512;  // Keep small for memory constrained ESP8266
+static constexpr uint16_t MAX_MESSAGE_SIZE = 8192;  // 8 KiB for ESP8266
 #else
-static constexpr uint16_t MAX_MESSAGE_SIZE = 2304;  // Support voice (1024) + headroom for larger messages
+static constexpr uint16_t MAX_MESSAGE_SIZE = 32768;  // 32 KiB for ESP32 and other platforms
 #endif
 
 // Forward declaration

esphome/components/api/api_frame_helper_noise.cpp

@@ -133,9 +133,6 @@ APIError APINoiseFrameHelper::loop() {
 }
 
 /** Read a packet into the rx_buf_.
- *
- * On success, rx_buf_ contains the frame data and state variables are cleared for the next read.
- * Caller is responsible for consuming rx_buf_ (e.g., via std::move).
  *
  * @return APIError::OK if a full packet is in rx_buf_
  *
@@ -176,18 +173,12 @@ APIError APINoiseFrameHelper::try_read_frame_() {
   // read body
   uint16_t msg_size = (((uint16_t) rx_header_buf_[1]) << 8) | rx_header_buf_[2];
 
-  if (state_ != State::DATA && msg_size > 128) {
-    // for handshake message only permit up to 128 bytes
+  // Check against size limits to prevent OOM: MAX_HANDSHAKE_SIZE for handshake, MAX_MESSAGE_SIZE for data
+  uint16_t limit = (state_ == State::DATA) ? MAX_MESSAGE_SIZE : MAX_HANDSHAKE_SIZE;
+  if (msg_size > limit) {
     state_ = State::FAILED;
-    HELPER_LOG("Bad packet len for handshake: %d", msg_size);
-    return APIError::BAD_HANDSHAKE_PACKET_LEN;
-  }
-
-  // Check against maximum message size to prevent OOM
-  if (msg_size > MAX_MESSAGE_SIZE) {
-    state_ = State::FAILED;
-    HELPER_LOG("Bad packet: message size %u exceeds maximum %u", msg_size, MAX_MESSAGE_SIZE);
-    return APIError::BAD_DATA_PACKET;
+    HELPER_LOG("Bad packet: message size %u exceeds maximum %u", msg_size, limit);
+    return (state_ == State::DATA) ? APIError::BAD_DATA_PACKET : APIError::BAD_HANDSHAKE_PACKET_LEN;
   }
 
   // Reserve space for body

esphome/components/api/api_frame_helper_plaintext.cpp

@@ -48,9 +48,6 @@ APIError APIPlaintextFrameHelper::loop() {
 }
 
 /** Read a packet into the rx_buf_.
- *
- * On success, rx_buf_ contains the frame data and state variables are cleared for the next read.
- * Caller is responsible for consuming rx_buf_ (e.g., via std::move).
  *
  * @return See APIError
  *

esphome/components/audio/__init__.py

@@ -165,4 +165,4 @@ def final_validate_audio_schema(
 
 
 async def to_code(config):
-    cg.add_library("esphome/esp-audio-libs", "1.1.4")
+    cg.add_library("esphome/esp-audio-libs", "2.0.1")

esphome/components/audio/audio_decoder.cpp

@@ -229,18 +229,18 @@ FileDecoderState AudioDecoder::decode_flac_() {
     auto result = this->flac_decoder_->read_header(this->input_transfer_buffer_->get_buffer_start(),
                                                    this->input_transfer_buffer_->available());
 
-    if (result == esp_audio_libs::flac::FLAC_DECODER_HEADER_OUT_OF_DATA) {
-      return FileDecoderState::POTENTIALLY_FAILED;
-    }
-
-    if (result != esp_audio_libs::flac::FLAC_DECODER_SUCCESS) {
-      // Couldn't read FLAC header
+    if (result > esp_audio_libs::flac::FLAC_DECODER_HEADER_OUT_OF_DATA) {
+      // Serrious error reading FLAC header, there is no recovery
       return FileDecoderState::FAILED;
     }
 
     size_t bytes_consumed = this->flac_decoder_->get_bytes_index();
     this->input_transfer_buffer_->decrease_buffer_length(bytes_consumed);
 
+    if (result == esp_audio_libs::flac::FLAC_DECODER_HEADER_OUT_OF_DATA) {
+      return FileDecoderState::MORE_TO_PROCESS;
+    }
+
     // Reallocate the output transfer buffer to the smallest necessary size
     this->free_buffer_required_ = flac_decoder_->get_output_buffer_size_bytes();
     if (!this->output_transfer_buffer_->reallocate(this->free_buffer_required_)) {
@@ -256,9 +256,9 @@ FileDecoderState AudioDecoder::decode_flac_() {
   }
 
   uint32_t output_samples = 0;
-  auto result = this->flac_decoder_->decode_frame(
-      this->input_transfer_buffer_->get_buffer_start(), this->input_transfer_buffer_->available(),
-      reinterpret_cast<int16_t *>(this->output_transfer_buffer_->get_buffer_end()), &output_samples);
+  auto result = this->flac_decoder_->decode_frame(this->input_transfer_buffer_->get_buffer_start(),
+                                                  this->input_transfer_buffer_->available(),
+                                                  this->output_transfer_buffer_->get_buffer_end(), &output_samples);
 
   if (result == esp_audio_libs::flac::FLAC_DECODER_ERROR_OUT_OF_DATA) {
     // Not an issue, just needs more data that we'll get next time.

esphome/components/canbus/canbus.h

@@ -105,9 +105,9 @@ class Canbus : public Component {
   CallbackManager<void(uint32_t can_id, bool extended_id, bool rtr, const std::vector<uint8_t> &data)>
       callback_manager_{};
 
-  virtual bool setup_internal();
-  virtual Error send_message(struct CanFrame *frame);
-  virtual Error read_message(struct CanFrame *frame);
+  virtual bool setup_internal() = 0;
+  virtual Error send_message(struct CanFrame *frame) = 0;
+  virtual Error read_message(struct CanFrame *frame) = 0;
 };
 
 template<typename... Ts> class CanbusSendAction : public Action<Ts...>, public Parented<Canbus> {

esphome/components/dashboard_import/dashboard_import.cpp

@@ -5,7 +5,7 @@ namespace dashboard_import {
 
 static std::string g_package_import_url;  // NOLINT
 
-std::string get_package_import_url() { return g_package_import_url; }
+const std::string &get_package_import_url() { return g_package_import_url; }
 void set_package_import_url(std::string url) { g_package_import_url = std::move(url); }
 
 }  // namespace dashboard_import

esphome/components/dashboard_import/dashboard_import.h

@@ -5,7 +5,7 @@
 namespace esphome {
 namespace dashboard_import {
 
-std::string get_package_import_url();
+const std::string &get_package_import_url();
 void set_package_import_url(std::string url);
 
 }  // namespace dashboard_import

esphome/components/epaper_spi/__init__.py

@@ -0,0 +1 @@
+CODEOWNERS = ["@esphome/core"]

esphome/components/epaper_spi/display.py

@@ -0,0 +1,80 @@
+from esphome import core, pins
+import esphome.codegen as cg
+from esphome.components import display, spi
+import esphome.config_validation as cv
+from esphome.const import (
+    CONF_BUSY_PIN,
+    CONF_DC_PIN,
+    CONF_ID,
+    CONF_LAMBDA,
+    CONF_MODEL,
+    CONF_PAGES,
+    CONF_RESET_DURATION,
+    CONF_RESET_PIN,
+)
+
+AUTO_LOAD = ["split_buffer"]
+DEPENDENCIES = ["spi"]
+
+epaper_spi_ns = cg.esphome_ns.namespace("epaper_spi")
+EPaperBase = epaper_spi_ns.class_(
+    "EPaperBase", cg.PollingComponent, spi.SPIDevice, display.DisplayBuffer
+)
+
+EPaperSpectraE6 = epaper_spi_ns.class_("EPaperSpectraE6", EPaperBase)
+EPaper7p3InSpectraE6 = epaper_spi_ns.class_("EPaper7p3InSpectraE6", EPaperSpectraE6)
+
+MODELS = {
+    "7.3in-spectra-e6": EPaper7p3InSpectraE6,
+}
+
+
+CONFIG_SCHEMA = cv.All(
+    display.FULL_DISPLAY_SCHEMA.extend(
+        {
+            cv.GenerateID(): cv.declare_id(EPaperBase),
+            cv.Required(CONF_DC_PIN): pins.gpio_output_pin_schema,
+            cv.Required(CONF_MODEL): cv.one_of(*MODELS, lower=True, space="-"),
+            cv.Optional(CONF_RESET_PIN): pins.gpio_output_pin_schema,
+            cv.Optional(CONF_BUSY_PIN): pins.gpio_input_pin_schema,
+            cv.Optional(CONF_RESET_DURATION): cv.All(
+                cv.positive_time_period_milliseconds,
+                cv.Range(max=core.TimePeriod(milliseconds=500)),
+            ),
+        }
+    )
+    .extend(cv.polling_component_schema("60s"))
+    .extend(spi.spi_device_schema()),
+    cv.has_at_most_one_key(CONF_PAGES, CONF_LAMBDA),
+)
+
+FINAL_VALIDATE_SCHEMA = spi.final_validate_device_schema(
+    "epaper_spi", require_miso=False, require_mosi=True
+)
+
+
+async def to_code(config):
+    model = MODELS[config[CONF_MODEL]]
+
+    rhs = model.new()
+    var = cg.Pvariable(config[CONF_ID], rhs, model)
+
+    await display.register_display(var, config)
+    await spi.register_spi_device(var, config)
+
+    dc = await cg.gpio_pin_expression(config[CONF_DC_PIN])
+    cg.add(var.set_dc_pin(dc))
+
+    if CONF_LAMBDA in config:
+        lambda_ = await cg.process_lambda(
+            config[CONF_LAMBDA], [(display.DisplayRef, "it")], return_type=cg.void
+        )
+        cg.add(var.set_writer(lambda_))
+    if CONF_RESET_PIN in config:
+        reset = await cg.gpio_pin_expression(config[CONF_RESET_PIN])
+        cg.add(var.set_reset_pin(reset))
+    if CONF_BUSY_PIN in config:
+        busy = await cg.gpio_pin_expression(config[CONF_BUSY_PIN])
+        cg.add(var.set_busy_pin(busy))
+    if CONF_RESET_DURATION in config:
+        cg.add(var.set_reset_duration(config[CONF_RESET_DURATION]))

esphome/components/epaper_spi/epaper_spi.cpp

@@ -0,0 +1,227 @@
+#include "epaper_spi.h"
+#include <cinttypes>
+#include "esphome/core/application.h"
+#include "esphome/core/helpers.h"
+#include "esphome/core/log.h"
+
+namespace esphome::epaper_spi {
+
+static const char *const TAG = "epaper_spi";
+
+static const LogString *epaper_state_to_string(EPaperState state) {
+  switch (state) {
+    case EPaperState::IDLE:
+      return LOG_STR("IDLE");
+    case EPaperState::UPDATE:
+      return LOG_STR("UPDATE");
+    case EPaperState::RESET:
+      return LOG_STR("RESET");
+    case EPaperState::INITIALISE:
+      return LOG_STR("INITIALISE");
+    case EPaperState::TRANSFER_DATA:
+      return LOG_STR("TRANSFER_DATA");
+    case EPaperState::POWER_ON:
+      return LOG_STR("POWER_ON");
+    case EPaperState::REFRESH_SCREEN:
+      return LOG_STR("REFRESH_SCREEN");
+    case EPaperState::POWER_OFF:
+      return LOG_STR("POWER_OFF");
+    case EPaperState::DEEP_SLEEP:
+      return LOG_STR("DEEP_SLEEP");
+    default:
+      return LOG_STR("UNKNOWN");
+  }
+}
+
+void EPaperBase::setup() {
+  if (!this->init_buffer_(this->get_buffer_length())) {
+    this->mark_failed("Failed to initialise buffer");
+    return;
+  }
+  this->setup_pins_();
+  this->spi_setup();
+}
+
+bool EPaperBase::init_buffer_(size_t buffer_length) {
+  if (!this->buffer_.init(buffer_length)) {
+    return false;
+  }
+  this->clear();
+  return true;
+}
+
+void EPaperBase::setup_pins_() {
+  this->dc_pin_->setup();  // OUTPUT
+  this->dc_pin_->digital_write(false);
+
+  if (this->reset_pin_ != nullptr) {
+    this->reset_pin_->setup();  // OUTPUT
+    this->reset_pin_->digital_write(true);
+  }
+
+  if (this->busy_pin_ != nullptr) {
+    this->busy_pin_->setup();  // INPUT
+  }
+}
+
+float EPaperBase::get_setup_priority() const { return setup_priority::PROCESSOR; }
+
+void EPaperBase::command(uint8_t value) {
+  this->start_command_();
+  this->write_byte(value);
+  this->end_command_();
+}
+
+void EPaperBase::data(uint8_t value) {
+  this->start_data_();
+  this->write_byte(value);
+  this->end_data_();
+}
+
+// write a command followed by zero or more bytes of data.
+// The command is the first byte, length is the length of data only in the second byte, followed by the data.
+// [COMMAND, LENGTH, DATA...]
+void EPaperBase::cmd_data(const uint8_t *data) {
+  const uint8_t command = data[0];
+  const uint8_t length = data[1];
+  const uint8_t *ptr = data + 2;
+
+  ESP_LOGVV(TAG, "Command: 0x%02X, Length: %d, Data: %s", command, length,
+            format_hex_pretty(ptr, length, '.', false).c_str());
+
+  this->dc_pin_->digital_write(false);
+  this->enable();
+  this->write_byte(command);
+  if (length > 0) {
+    this->dc_pin_->digital_write(true);
+    this->write_array(ptr, length);
+  }
+  this->disable();
+}
+
+bool EPaperBase::is_idle_() {
+  if (this->busy_pin_ == nullptr) {
+    return true;
+  }
+  return !this->busy_pin_->digital_read();
+}
+
+void EPaperBase::reset() {
+  if (this->reset_pin_ != nullptr) {
+    this->reset_pin_->digital_write(false);
+    this->disable_loop();
+    this->set_timeout(this->reset_duration_, [this] {
+      this->reset_pin_->digital_write(true);
+      this->set_timeout(20, [this] { this->enable_loop(); });
+    });
+  }
+}
+
+void EPaperBase::update() {
+  if (!this->state_queue_.empty()) {
+    ESP_LOGE(TAG, "Display update already in progress - %s",
+             LOG_STR_ARG(epaper_state_to_string(this->state_queue_.front())));
+    return;
+  }
+
+  this->state_queue_.push(EPaperState::UPDATE);
+  this->state_queue_.push(EPaperState::RESET);
+  this->state_queue_.push(EPaperState::INITIALISE);
+  this->state_queue_.push(EPaperState::TRANSFER_DATA);
+  this->state_queue_.push(EPaperState::POWER_ON);
+  this->state_queue_.push(EPaperState::REFRESH_SCREEN);
+  this->state_queue_.push(EPaperState::POWER_OFF);
+  this->state_queue_.push(EPaperState::DEEP_SLEEP);
+  this->state_queue_.push(EPaperState::IDLE);
+
+  this->enable_loop();
+}
+
+void EPaperBase::loop() {
+  if (this->waiting_for_idle_) {
+    if (this->is_idle_()) {
+      this->waiting_for_idle_ = false;
+    } else {
+      if (App.get_loop_component_start_time() - this->waiting_for_idle_last_print_ >= 1000) {
+        ESP_LOGV(TAG, "Waiting for idle");
+        this->waiting_for_idle_last_print_ = App.get_loop_component_start_time();
+      }
+      return;
+    }
+  }
+
+  auto state = this->state_queue_.front();
+
+  switch (state) {
+    case EPaperState::IDLE:
+      this->disable_loop();
+      break;
+    case EPaperState::UPDATE:
+      this->do_update_();  // Calls ESPHome (current page) lambda
+      break;
+    case EPaperState::RESET:
+      this->reset();
+      break;
+    case EPaperState::INITIALISE:
+      this->initialise_();
+      break;
+    case EPaperState::TRANSFER_DATA:
+      if (!this->transfer_data()) {
+        return;  // Not done yet, come back next loop
+      }
+      break;
+    case EPaperState::POWER_ON:
+      this->power_on();
+      break;
+    case EPaperState::REFRESH_SCREEN:
+      this->refresh_screen();
+      break;
+    case EPaperState::POWER_OFF:
+      this->power_off();
+      break;
+    case EPaperState::DEEP_SLEEP:
+      this->deep_sleep();
+      break;
+  }
+  this->state_queue_.pop();
+}
+
+void EPaperBase::start_command_() {
+  this->dc_pin_->digital_write(false);
+  this->enable();
+}
+
+void EPaperBase::end_command_() { this->disable(); }
+
+void EPaperBase::start_data_() {
+  this->dc_pin_->digital_write(true);
+  this->enable();
+}
+void EPaperBase::end_data_() { this->disable(); }
+
+void EPaperBase::on_safe_shutdown() { this->deep_sleep(); }
+
+void EPaperBase::initialise_() {
+  size_t index = 0;
+  const auto &sequence = this->init_sequence_;
+  const size_t sequence_size = this->init_sequence_length_;
+  while (index != sequence_size) {
+    if (sequence_size - index < 2) {
+      this->mark_failed("Malformed init sequence");
+      return;
+    }
+    const auto *ptr = sequence + index;
+    const uint8_t length = ptr[1];
+    if (sequence_size - index < length + 2) {
+      this->mark_failed("Malformed init sequence");
+      return;
+    }
+
+    this->cmd_data(ptr);
+    index += length + 2;
+  }
+
+  this->power_on();
+}
+
+}  // namespace esphome::epaper_spi

esphome/components/epaper_spi/epaper_spi.h

@@ -0,0 +1,93 @@
+#pragma once
+
+#include "esphome/components/display/display_buffer.h"
+#include "esphome/components/spi/spi.h"
+#include "esphome/components/split_buffer/split_buffer.h"
+#include "esphome/core/component.h"
+
+#include <queue>
+
+namespace esphome::epaper_spi {
+
+enum class EPaperState : uint8_t {
+  IDLE,
+  UPDATE,
+  RESET,
+  INITIALISE,
+  TRANSFER_DATA,
+  POWER_ON,
+  REFRESH_SCREEN,
+  POWER_OFF,
+  DEEP_SLEEP,
+};
+
+static const uint8_t MAX_TRANSFER_TIME = 10;  // Transfer in 10ms blocks to allow the loop to run
+
+class EPaperBase : public display::DisplayBuffer,
+                   public spi::SPIDevice<spi::BIT_ORDER_MSB_FIRST, spi::CLOCK_POLARITY_LOW, spi::CLOCK_PHASE_LEADING,
+                                         spi::DATA_RATE_2MHZ> {
+ public:
+  EPaperBase(const uint8_t *init_sequence, const size_t init_sequence_length)
+      : init_sequence_length_(init_sequence_length), init_sequence_(init_sequence) {}
+  void set_dc_pin(GPIOPin *dc_pin) { dc_pin_ = dc_pin; }
+  float get_setup_priority() const override;
+  void set_reset_pin(GPIOPin *reset) { this->reset_pin_ = reset; }
+  void set_busy_pin(GPIOPin *busy) { this->busy_pin_ = busy; }
+  void set_reset_duration(uint32_t reset_duration) { this->reset_duration_ = reset_duration; }
+
+  void command(uint8_t value);
+  void data(uint8_t value);
+  void cmd_data(const uint8_t *data);
+
+  void update() override;
+  void loop() override;
+
+  void setup() override;
+
+  void on_safe_shutdown() override;
+
+ protected:
+  bool is_idle_();
+  void setup_pins_();
+  virtual void reset();
+  void initialise_();
+  bool init_buffer_(size_t buffer_length);
+
+  virtual int get_width_controller() { return this->get_width_internal(); };
+  virtual void deep_sleep() = 0;
+  /**
+   * Send data to the device via SPI
+   * @return true if done, false if should be called next loop
+   */
+  virtual bool transfer_data() = 0;
+  virtual void refresh_screen() = 0;
+
+  virtual void power_on() = 0;
+  virtual void power_off() = 0;
+  virtual uint32_t get_buffer_length() = 0;
+
+  void start_command_();
+  void end_command_();
+  void start_data_();
+  void end_data_();
+
+  const size_t init_sequence_length_{0};
+
+  size_t current_data_index_{0};
+  uint32_t reset_duration_{200};
+  uint32_t waiting_for_idle_last_print_{0};
+
+  GPIOPin *dc_pin_;
+  GPIOPin *busy_pin_{nullptr};
+  GPIOPin *reset_pin_{nullptr};
+
+  const uint8_t *init_sequence_{nullptr};
+
+  bool waiting_for_idle_{false};
+
+  split_buffer::SplitBuffer buffer_;
+
+  std::queue<EPaperState> state_queue_{{EPaperState::IDLE}};
+};
+
+}  // namespace esphome::epaper_spi

esphome/components/epaper_spi/epaper_spi_model_7p3in_spectra_e6.cpp

@@ -0,0 +1,42 @@
+#include "epaper_spi_model_7p3in_spectra_e6.h"
+
+namespace esphome::epaper_spi {
+
+static constexpr const char *const TAG = "epaper_spi.7.3in-spectra-e6";
+
+void EPaper7p3InSpectraE6::power_on() {
+  ESP_LOGI(TAG, "Power on");
+  this->command(0x04);
+  this->waiting_for_idle_ = true;
+}
+
+void EPaper7p3InSpectraE6::power_off() {
+  ESP_LOGI(TAG, "Power off");
+  this->command(0x02);
+  this->data(0x00);
+  this->waiting_for_idle_ = true;
+}
+
+void EPaper7p3InSpectraE6::refresh_screen() {
+  ESP_LOGI(TAG, "Refresh");
+  this->command(0x12);
+  this->data(0x00);
+  this->waiting_for_idle_ = true;
+}
+
+void EPaper7p3InSpectraE6::deep_sleep() {
+  ESP_LOGI(TAG, "Deep sleep");
+  this->command(0x07);
+  this->data(0xA5);
+}
+
+void EPaper7p3InSpectraE6::dump_config() {
+  LOG_DISPLAY("", "E-Paper SPI", this);
+  ESP_LOGCONFIG(TAG, "  Model: 7.3in Spectra E6");
+  LOG_PIN("  Reset Pin: ", this->reset_pin_);
+  LOG_PIN("  DC Pin: ", this->dc_pin_);
+  LOG_PIN("  Busy Pin: ", this->busy_pin_);
+  LOG_UPDATE_INTERVAL(this);
+}
+
+}  // namespace esphome::epaper_spi

esphome/components/epaper_spi/epaper_spi_model_7p3in_spectra_e6.h

@@ -0,0 +1,45 @@
+#pragma once
+
+#include "epaper_spi_spectra_e6.h"
+
+namespace esphome::epaper_spi {
+
+class EPaper7p3InSpectraE6 : public EPaperSpectraE6 {
+  static constexpr const uint16_t WIDTH = 800;
+  static constexpr const uint16_t HEIGHT = 480;
+  // clang-format off
+
+  // Command, data length, data
+  static constexpr uint8_t INIT_SEQUENCE[] = {
+    0xAA, 6, 0x49, 0x55, 0x20, 0x08, 0x09, 0x18,
+    0x01, 1, 0x3F,
+    0x00, 2, 0x5F, 0x69,
+    0x03, 4, 0x00, 0x54, 0x00, 0x44,
+    0x05, 4, 0x40, 0x1F, 0x1F, 0x2C,
+    0x06, 4, 0x6F, 0x1F, 0x17, 0x49,
+    0x08, 4, 0x6F, 0x1F, 0x1F, 0x22,
+    0x30, 1, 0x03,
+    0x50, 1, 0x3F,
+    0x60, 2, 0x02, 0x00,
+    0x61, 4, WIDTH / 256, WIDTH % 256, HEIGHT / 256, HEIGHT % 256,
+    0x84, 1, 0x01,
+    0xE3, 1, 0x2F,
+  };
+  // clang-format on
+
+ public:
+  EPaper7p3InSpectraE6() : EPaperSpectraE6(INIT_SEQUENCE, sizeof(INIT_SEQUENCE)) {}
+
+  void dump_config() override;
+
+ protected:
+  int get_width_internal() override { return WIDTH; };
+  int get_height_internal() override { return HEIGHT; };
+
+  void refresh_screen() override;
+  void power_on() override;
+  void power_off() override;
+  void deep_sleep() override;
+};
+
+}  // namespace esphome::epaper_spi

esphome/components/epaper_spi/epaper_spi_spectra_e6.cpp

@@ -0,0 +1,135 @@
+#include "epaper_spi_spectra_e6.h"
+
+#include "esphome/core/log.h"
+
+namespace esphome::epaper_spi {
+
+static constexpr const char *const TAG = "epaper_spi.6c";
+
+static inline uint8_t color_to_hex(Color color) {
+  if (color.red > 127) {
+    if (color.green > 170) {
+      if (color.blue > 127) {
+        return 0x1;  // White
+      } else {
+        return 0x2;  // Yellow
+      }
+    } else {
+      return 0x3;  // Red (or Magenta)
+    }
+  } else {
+    if (color.green > 127) {
+      if (color.blue > 127) {
+        return 0x5;  // Cyan -> Blue
+      } else {
+        return 0x6;  // Green
+      }
+    } else {
+      if (color.blue > 127) {
+        return 0x5;  // Blue
+      } else {
+        return 0x0;  // Black
+      }
+    }
+  }
+}
+
+void EPaperSpectraE6::fill(Color color) {
+  uint8_t pixel_color;
+  if (color.is_on()) {
+    pixel_color = color_to_hex(color);
+  } else {
+    pixel_color = 0x1;
+  }
+
+  // We store 8 bitset<3> in 3 bytes
+  // | byte 1 | byte 2 | byte 3 |
+  // |aaabbbaa|abbbaaab|bbaaabbb|
+  uint8_t byte_1 = pixel_color << 5 | pixel_color << 2 | pixel_color >> 1;
+  uint8_t byte_2 = pixel_color << 7 | pixel_color << 4 | pixel_color << 1 | pixel_color >> 2;
+  uint8_t byte_3 = pixel_color << 6 | pixel_color << 3 | pixel_color << 0;
+
+  const size_t buffer_length = this->get_buffer_length();
+  for (size_t i = 0; i < buffer_length; i += 3) {
+    this->buffer_[i + 0] = byte_1;
+    this->buffer_[i + 1] = byte_2;
+    this->buffer_[i + 2] = byte_3;
+  }
+}
+
+uint32_t EPaperSpectraE6::get_buffer_length() {
+  // 6 colors buffer, 1 pixel = 3 bits, we will store 8 pixels in 24 bits = 3 bytes
+  return this->get_width_controller() * this->get_height_internal() / 8u * 3u;
+}
+
+void HOT EPaperSpectraE6::draw_absolute_pixel_internal(int x, int y, Color color) {
+  if (x >= this->get_width_internal() || y >= this->get_height_internal() || x < 0 || y < 0)
+    return;
+
+  uint8_t pixel_bits = color_to_hex(color);
+  uint32_t pixel_position = x + y * this->get_width_controller();
+  uint32_t first_bit_position = pixel_position * 3;
+  uint32_t byte_position = first_bit_position / 8u;
+  uint32_t byte_subposition = first_bit_position % 8u;
+
+  if (byte_subposition <= 5) {
+    this->buffer_[byte_position] = (this->buffer_[byte_position] & (0xFF ^ (0b111 << (5 - byte_subposition)))) |
+                                   (pixel_bits << (5 - byte_subposition));
+  } else {
+    this->buffer_[byte_position] = (this->buffer_[byte_position] & (0xFF ^ (0b111 >> (byte_subposition - 5)))) |
+                                   (pixel_bits >> (byte_subposition - 5));
+
+    this->buffer_[byte_position + 1] =
+        (this->buffer_[byte_position + 1] & (0xFF ^ (0xFF & (0b111 << (13 - byte_subposition))))) |
+        (pixel_bits << (13 - byte_subposition));
+  }
+}
+
+bool HOT EPaperSpectraE6::transfer_data() {
+  const uint32_t start_time = App.get_loop_component_start_time();
+  if (this->current_data_index_ == 0) {
+    ESP_LOGV(TAG, "Sending data");
+    this->command(0x10);
+  }
+
+  uint8_t bytes_to_send[4]{0};
+  const size_t buffer_length = this->get_buffer_length();
+  for (size_t i = this->current_data_index_; i < buffer_length; i += 3) {
+    const uint32_t triplet = encode_uint24(this->buffer_[i + 0], this->buffer_[i + 1], this->buffer_[i + 2]);
+    // 8 pixels are stored in 3 bytes
+    // |aaabbbaa|abbbaaab|bbaaabbb|
+    // | byte 1 | byte 2 | byte 3 |
+    bytes_to_send[0] = ((triplet >> 17) & 0b01110000) | ((triplet >> 18) & 0b00000111);
+    bytes_to_send[1] = ((triplet >> 11) & 0b01110000) | ((triplet >> 12) & 0b00000111);
+    bytes_to_send[2] = ((triplet >> 5) & 0b01110000) | ((triplet >> 6) & 0b00000111);
+    bytes_to_send[3] = ((triplet << 1) & 0b01110000) | ((triplet << 0) & 0b00000111);
+
+    this->start_data_();
+    this->write_array(bytes_to_send, sizeof(bytes_to_send));
+    this->end_data_();
+
+    if (millis() - start_time > MAX_TRANSFER_TIME) {
+      // Let the main loop run and come back next loop
+      this->current_data_index_ = i + 3;
+      return false;
+    }
+  }
+  // Finished the entire dataset
+  this->current_data_index_ = 0;
+  return true;
+}
+
+void EPaperSpectraE6::reset() {
+  if (this->reset_pin_ != nullptr) {
+    this->disable_loop();
+    this->reset_pin_->digital_write(true);
+    this->set_timeout(20, [this] {
+      this->reset_pin_->digital_write(false);
+      delay(2);
+      this->reset_pin_->digital_write(true);
+      this->set_timeout(20, [this] { this->enable_loop(); });
+    });
+  }
+}
+
+}  // namespace esphome::epaper_spi

esphome/components/epaper_spi/epaper_spi_spectra_e6.h

@@ -0,0 +1,23 @@
+#pragma once
+
+#include "epaper_spi.h"
+
+namespace esphome::epaper_spi {
+
+class EPaperSpectraE6 : public EPaperBase {
+ public:
+  EPaperSpectraE6(const uint8_t *init_sequence, const size_t init_sequence_length)
+      : EPaperBase(init_sequence, init_sequence_length) {}
+
+  display::DisplayType get_display_type() override { return display::DisplayType::DISPLAY_TYPE_COLOR; }
+  void fill(Color color) override;
+
+ protected:
+  void draw_absolute_pixel_internal(int x, int y, Color color) override;
+  uint32_t get_buffer_length() override;
+
+  bool transfer_data() override;
+  void reset() override;
+};
+
+}  // namespace esphome::epaper_spi

esphome/components/esp32/__init__.py

@@ -304,6 +304,17 @@ def _format_framework_espidf_version(ver: cv.Version, release: str) -> str:
     return f"pioarduino/framework-espidf@https://github.com/pioarduino/esp-idf/releases/download/v{str(ver)}/esp-idf-v{str(ver)}.zip"
 
 
+def _is_framework_url(source: str) -> str:
+    # platformio accepts many URL schemes for framework repositories and archives including http, https, git, file, and symlink
+    import urllib.parse
+
+    try:
+        parsed = urllib.parse.urlparse(source)
+    except ValueError:
+        return False
+    return bool(parsed.scheme)
+
+
 # NOTE: Keep this in mind when updating the recommended version:
 #  * New framework historically have had some regressions, especially for WiFi.
 #    The new version needs to be thoroughly validated before changing the
@@ -314,11 +325,12 @@ def _format_framework_espidf_version(ver: cv.Version, release: str) -> str:
 #  - https://github.com/espressif/arduino-esp32/releases
 ARDUINO_FRAMEWORK_VERSION_LOOKUP = {
     "recommended": cv.Version(3, 2, 1),
-    "latest": cv.Version(3, 3, 1),
-    "dev": cv.Version(3, 3, 1),
+    "latest": cv.Version(3, 3, 2),
+    "dev": cv.Version(3, 3, 2),
 }
 ARDUINO_PLATFORM_VERSION_LOOKUP = {
-    cv.Version(3, 3, 1): cv.Version(55, 3, 31),
+    cv.Version(3, 3, 2): cv.Version(55, 3, 31, "1"),
+    cv.Version(3, 3, 1): cv.Version(55, 3, 31, "1"),
     cv.Version(3, 3, 0): cv.Version(55, 3, 30, "2"),
     cv.Version(3, 2, 1): cv.Version(54, 3, 21, "2"),
     cv.Version(3, 2, 0): cv.Version(54, 3, 20),
@@ -336,8 +348,8 @@ ESP_IDF_FRAMEWORK_VERSION_LOOKUP = {
     "dev": cv.Version(5, 5, 1),
 }
 ESP_IDF_PLATFORM_VERSION_LOOKUP = {
-    cv.Version(5, 5, 1): cv.Version(55, 3, 31),
-    cv.Version(5, 5, 0): cv.Version(55, 3, 31),
+    cv.Version(5, 5, 1): cv.Version(55, 3, 31, "1"),
+    cv.Version(5, 5, 0): cv.Version(55, 3, 31, "1"),
     cv.Version(5, 4, 2): cv.Version(54, 3, 21, "2"),
     cv.Version(5, 4, 1): cv.Version(54, 3, 21, "2"),
     cv.Version(5, 4, 0): cv.Version(54, 3, 21, "2"),
@@ -352,8 +364,8 @@ ESP_IDF_PLATFORM_VERSION_LOOKUP = {
 #  - https://github.com/pioarduino/platform-espressif32/releases
 PLATFORM_VERSION_LOOKUP = {
     "recommended": cv.Version(54, 3, 21, "2"),
-    "latest": cv.Version(55, 3, 31),
-    "dev": "https://github.com/pioarduino/platform-espressif32.git#develop",
+    "latest": cv.Version(55, 3, 31, "1"),
+    "dev": cv.Version(55, 3, 31, "1"),
 }
 
 
@@ -386,6 +398,10 @@ def _check_versions(value):
         value[CONF_SOURCE] = value.get(
             CONF_SOURCE, _format_framework_arduino_version(version)
         )
+        if _is_framework_url(value[CONF_SOURCE]):
+            value[CONF_SOURCE] = (
+                f"pioarduino/framework-arduinoespressif32@{value[CONF_SOURCE]}"
+            )
     else:
         if version < cv.Version(5, 0, 0):
             raise cv.Invalid("Only ESP-IDF 5.0+ is supported.")
@@ -395,6 +411,8 @@ def _check_versions(value):
             CONF_SOURCE,
             _format_framework_espidf_version(version, value.get(CONF_RELEASE, None)),
         )
+        if _is_framework_url(value[CONF_SOURCE]):
+            value[CONF_SOURCE] = f"pioarduino/framework-espidf@{value[CONF_SOURCE]}"
 
     if CONF_PLATFORM_VERSION not in value:
         if platform_lookup is None:
@@ -639,6 +657,7 @@ def _show_framework_migration_message(name: str, variant: str) -> None:
         + "Why change? ESP-IDF offers:\n"
         + color(AnsiFore.GREEN, "  ✨ Up to 40% smaller binaries\n")
         + color(AnsiFore.GREEN, "  🚀 Better performance and optimization\n")
+        + color(AnsiFore.GREEN, "  ⚡ 2-3x faster compile times\n")
         + color(AnsiFore.GREEN, "  📦 Custom-built firmware for your exact needs\n")
         + color(
             AnsiFore.GREEN,
@@ -646,7 +665,6 @@ def _show_framework_migration_message(name: str, variant: str) -> None:
         )
         + "\n"
         + "Trade-offs:\n"
-        + color(AnsiFore.YELLOW, "  ⏱️  Compile times are ~25% longer\n")
         + color(AnsiFore.YELLOW, "  🔄 Some components need migration\n")
         + "\n"
         + "What should I do?\n"

esphome/components/esp32_ble/__init__.py

@@ -285,6 +285,10 @@ def consume_connection_slots(
 
 def validate_connection_slots(max_connections: int) -> None:
     """Validate that BLE connection slots don't exceed the configured maximum."""
+    # Skip validation in testing mode to allow component grouping
+    if CORE.testing_mode:
+        return
+
     ble_data = CORE.data.get(KEY_ESP32_BLE, {})
     used_slots = ble_data.get(KEY_USED_CONNECTION_SLOTS, [])
     num_used = len(used_slots)
@@ -332,12 +336,16 @@ def final_validation(config):
 
     # Check if BLE Server is needed
     has_ble_server = "esp32_ble_server" in full_config
-    add_idf_sdkconfig_option("CONFIG_BT_GATTS_ENABLE", has_ble_server)
 
     # Check if BLE Client is needed (via esp32_ble_tracker or esp32_ble_client)
     has_ble_client = (
         "esp32_ble_tracker" in full_config or "esp32_ble_client" in full_config
     )
+
+    # ESP-IDF BLE stack requires GATT Server to be enabled when GATT Client is enabled
+    # This is an internal dependency in the Bluedroid stack (tested ESP-IDF 5.4.2-5.5.1)
+    # See: https://github.com/espressif/esp-idf/issues/17724
+    add_idf_sdkconfig_option("CONFIG_BT_GATTS_ENABLE", has_ble_server or has_ble_client)
     add_idf_sdkconfig_option("CONFIG_BT_GATTC_ENABLE", has_ble_client)
 
     # Handle max_connections: check for deprecated location in esp32_ble_tracker

esphome/components/esp32_ble/ble.cpp

@@ -217,8 +217,11 @@ bool ESP32BLE::ble_setup_() {
   if (this->name_.has_value()) {
     name = this->name_.value();
     if (App.is_name_add_mac_suffix_enabled()) {
-      name += "-";
-      name += get_mac_address().substr(6);
+      // MAC address suffix length (last 6 characters of 12-char MAC address string)
+      constexpr size_t mac_address_suffix_len = 6;
+      const std::string mac_addr = get_mac_address();
+      const char *mac_suffix_ptr = mac_addr.c_str() + mac_address_suffix_len;
+      name = make_name_with_suffix(name, '-', mac_suffix_ptr, mac_address_suffix_len);
     }
   } else {
     name = App.get_name();

esphome/components/esp32_ble_beacon/esp32_ble_beacon.cpp

@@ -15,10 +15,6 @@
 #include "esphome/core/hal.h"
 #include "esphome/core/helpers.h"
 
-#ifdef USE_ARDUINO
-#include <esp32-hal-bt.h>
-#endif
-
 namespace esphome {
 namespace esp32_ble_beacon {
 

esphome/components/esp32_ble_tracker/__init__.py

@@ -1,5 +1,6 @@
 from __future__ import annotations
 
+from dataclasses import dataclass
 import logging
 
 from esphome import automation
@@ -52,9 +53,19 @@ class BLEFeatures(StrEnum):
     ESP_BT_DEVICE = "ESP_BT_DEVICE"
 
 
+# Dataclass for registration counts
+@dataclass
+class RegistrationCounts:
+    listeners: int = 0
+    clients: int = 0
+
+
 # Set to track which features are needed by components
 _required_features: set[BLEFeatures] = set()
 
+# Track registration counts for StaticVector sizing
+_registration_counts = RegistrationCounts()
+
 
 def register_ble_features(features: set[BLEFeatures]) -> None:
     """Register BLE features that a component needs.
@@ -257,12 +268,14 @@ async def to_code(config):
         register_ble_features({BLEFeatures.ESP_BT_DEVICE})
 
     for conf in config.get(CONF_ON_BLE_ADVERTISE, []):
+        _registration_counts.listeners += 1
         trigger = cg.new_Pvariable(conf[CONF_TRIGGER_ID], var)
         if CONF_MAC_ADDRESS in conf:
             addr_list = [it.as_hex for it in conf[CONF_MAC_ADDRESS]]
             cg.add(trigger.set_addresses(addr_list))
         await automation.build_automation(trigger, [(ESPBTDeviceConstRef, "x")], conf)
     for conf in config.get(CONF_ON_BLE_SERVICE_DATA_ADVERTISE, []):
+        _registration_counts.listeners += 1
         trigger = cg.new_Pvariable(conf[CONF_TRIGGER_ID], var)
         if len(conf[CONF_SERVICE_UUID]) == len(bt_uuid16_format):
             cg.add(trigger.set_service_uuid16(as_hex(conf[CONF_SERVICE_UUID])))
@@ -275,6 +288,7 @@ async def to_code(config):
             cg.add(trigger.set_address(conf[CONF_MAC_ADDRESS].as_hex))
         await automation.build_automation(trigger, [(adv_data_t_const_ref, "x")], conf)
     for conf in config.get(CONF_ON_BLE_MANUFACTURER_DATA_ADVERTISE, []):
+        _registration_counts.listeners += 1
         trigger = cg.new_Pvariable(conf[CONF_TRIGGER_ID], var)
         if len(conf[CONF_MANUFACTURER_ID]) == len(bt_uuid16_format):
             cg.add(trigger.set_manufacturer_uuid16(as_hex(conf[CONF_MANUFACTURER_ID])))
@@ -287,6 +301,7 @@ async def to_code(config):
             cg.add(trigger.set_address(conf[CONF_MAC_ADDRESS].as_hex))
         await automation.build_automation(trigger, [(adv_data_t_const_ref, "x")], conf)
     for conf in config.get(CONF_ON_SCAN_END, []):
+        _registration_counts.listeners += 1
         trigger = cg.new_Pvariable(conf[CONF_TRIGGER_ID], var)
         await automation.build_automation(trigger, [], conf)
 
@@ -320,6 +335,17 @@ async def _add_ble_features():
         cg.add_define("USE_ESP32_BLE_DEVICE")
         cg.add_define("USE_ESP32_BLE_UUID")
 
+    # Add defines for StaticVector sizing based on registration counts
+    # Only define if count > 0 to avoid allocating unnecessary memory
+    if _registration_counts.listeners > 0:
+        cg.add_define(
+            "ESPHOME_ESP32_BLE_TRACKER_LISTENER_COUNT", _registration_counts.listeners
+        )
+    if _registration_counts.clients > 0:
+        cg.add_define(
+            "ESPHOME_ESP32_BLE_TRACKER_CLIENT_COUNT", _registration_counts.clients
+        )
+
 
 ESP32_BLE_START_SCAN_ACTION_SCHEMA = cv.Schema(
     {
@@ -369,6 +395,7 @@ async def register_ble_device(
     var: cg.SafeExpType, config: ConfigType
 ) -> cg.SafeExpType:
     register_ble_features({BLEFeatures.ESP_BT_DEVICE})
+    _registration_counts.listeners += 1
     paren = await cg.get_variable(config[CONF_ESP32_BLE_ID])
     cg.add(paren.register_listener(var))
     return var
@@ -376,6 +403,7 @@ async def register_ble_device(
 
 async def register_client(var: cg.SafeExpType, config: ConfigType) -> cg.SafeExpType:
     register_ble_features({BLEFeatures.ESP_BT_DEVICE})
+    _registration_counts.clients += 1
     paren = await cg.get_variable(config[CONF_ESP32_BLE_ID])
     cg.add(paren.register_client(var))
     return var
@@ -389,6 +417,7 @@ async def register_raw_ble_device(
     This does NOT register the ESP_BT_DEVICE feature, meaning ESPBTDevice
     will not be compiled in if this is the only registration method used.
     """
+    _registration_counts.listeners += 1
     paren = await cg.get_variable(config[CONF_ESP32_BLE_ID])
     cg.add(paren.register_listener(var))
     return var
@@ -402,6 +431,7 @@ async def register_raw_client(
     This does NOT register the ESP_BT_DEVICE feature, meaning ESPBTDevice
     will not be compiled in if this is the only registration method used.
     """
+    _registration_counts.clients += 1
     paren = await cg.get_variable(config[CONF_ESP32_BLE_ID])
     cg.add(paren.register_client(var))
     return var

esphome/components/esp32_ble_tracker/esp32_ble_tracker.cpp

@@ -25,10 +25,6 @@
 #include <esp_coexist.h>
 #endif
 
-#ifdef USE_ARDUINO
-#include <esp32-hal-bt.h>
-#endif
-
 #define MBEDTLS_AES_ALT
 #include <aes_alt.h>
 
@@ -78,9 +74,11 @@ void ESP32BLETracker::setup() {
       [this](ota::OTAState state, float progress, uint8_t error, ota::OTAComponent *comp) {
         if (state == ota::OTA_STARTED) {
           this->stop_scan();
+#ifdef ESPHOME_ESP32_BLE_TRACKER_CLIENT_COUNT
           for (auto *client : this->clients_) {
             client->disconnect();
           }
+#endif
         }
       });
 #endif
@@ -210,8 +208,10 @@ void ESP32BLETracker::start_scan_(bool first) {
   this->set_scanner_state_(ScannerState::STARTING);
   ESP_LOGD(TAG, "Starting scan, set scanner state to STARTING.");
   if (!first) {
+#ifdef ESPHOME_ESP32_BLE_TRACKER_LISTENER_COUNT
     for (auto *listener : this->listeners_)
       listener->on_scan_end();
+#endif
   }
 #ifdef USE_ESP32_BLE_DEVICE
   this->already_discovered_.clear();
@@ -240,20 +240,25 @@ void ESP32BLETracker::start_scan_(bool first) {
 }
 
 void ESP32BLETracker::register_client(ESPBTClient *client) {
+#ifdef ESPHOME_ESP32_BLE_TRACKER_CLIENT_COUNT
   client->app_id = ++this->app_id_;
   this->clients_.push_back(client);
   this->recalculate_advertisement_parser_types();
+#endif
 }
 
 void ESP32BLETracker::register_listener(ESPBTDeviceListener *listener) {
+#ifdef ESPHOME_ESP32_BLE_TRACKER_LISTENER_COUNT
   listener->set_parent(this);
   this->listeners_.push_back(listener);
   this->recalculate_advertisement_parser_types();
+#endif
 }
 
 void ESP32BLETracker::recalculate_advertisement_parser_types() {
   this->raw_advertisements_ = false;
   this->parse_advertisements_ = false;
+#ifdef ESPHOME_ESP32_BLE_TRACKER_LISTENER_COUNT
   for (auto *listener : this->listeners_) {
     if (listener->get_advertisement_parser_type() == AdvertisementParserType::PARSED_ADVERTISEMENTS) {
       this->parse_advertisements_ = true;
@@ -261,6 +266,8 @@ void ESP32BLETracker::recalculate_advertisement_parser_types() {
       this->raw_advertisements_ = true;
     }
   }
+#endif
+#ifdef ESPHOME_ESP32_BLE_TRACKER_CLIENT_COUNT
   for (auto *client : this->clients_) {
     if (client->get_advertisement_parser_type() == AdvertisementParserType::PARSED_ADVERTISEMENTS) {
       this->parse_advertisements_ = true;
@@ -268,6 +275,7 @@ void ESP32BLETracker::recalculate_advertisement_parser_types() {
       this->raw_advertisements_ = true;
     }
   }
+#endif
 }
 
 void ESP32BLETracker::gap_event_handler(esp_gap_ble_cb_event_t event, esp_ble_gap_cb_param_t *param) {
@@ -286,10 +294,12 @@ void ESP32BLETracker::gap_event_handler(esp_gap_ble_cb_event_t event, esp_ble_ga
     default:
       break;
   }
-  // Forward all events to clients (scan results are handled separately via gap_scan_event_handler)
+    // Forward all events to clients (scan results are handled separately via gap_scan_event_handler)
+#ifdef ESPHOME_ESP32_BLE_TRACKER_CLIENT_COUNT
   for (auto *client : this->clients_) {
     client->gap_event_handler(event, param);
   }
+#endif
 }
 
 void ESP32BLETracker::gap_scan_event_handler(const BLEScanResult &scan_result) {
@@ -352,9 +362,11 @@ void ESP32BLETracker::gap_scan_stop_complete_(const esp_ble_gap_cb_param_t::ble_
 
 void ESP32BLETracker::gattc_event_handler(esp_gattc_cb_event_t event, esp_gatt_if_t gattc_if,
                                           esp_ble_gattc_cb_param_t *param) {
+#ifdef ESPHOME_ESP32_BLE_TRACKER_CLIENT_COUNT
   for (auto *client : this->clients_) {
     client->gattc_event_handler(event, gattc_if, param);
   }
+#endif
 }
 
 void ESP32BLETracker::set_scanner_state_(ScannerState state) {
@@ -708,12 +720,16 @@ bool ESPBTDevice::resolve_irk(const uint8_t *irk) const {
 void ESP32BLETracker::process_scan_result_(const BLEScanResult &scan_result) {
   // Process raw advertisements
   if (this->raw_advertisements_) {
+#ifdef ESPHOME_ESP32_BLE_TRACKER_LISTENER_COUNT
     for (auto *listener : this->listeners_) {
       listener->parse_devices(&scan_result, 1);
     }
+#endif
+#ifdef ESPHOME_ESP32_BLE_TRACKER_CLIENT_COUNT
     for (auto *client : this->clients_) {
       client->parse_devices(&scan_result, 1);
     }
+#endif
   }
 
   // Process parsed advertisements
@@ -723,16 +739,20 @@ void ESP32BLETracker::process_scan_result_(const BLEScanResult &scan_result) {
     device.parse_scan_rst(scan_result);
 
     bool found = false;
+#ifdef ESPHOME_ESP32_BLE_TRACKER_LISTENER_COUNT
     for (auto *listener : this->listeners_) {
       if (listener->parse_device(device))
         found = true;
     }
+#endif
 
+#ifdef ESPHOME_ESP32_BLE_TRACKER_CLIENT_COUNT
     for (auto *client : this->clients_) {
       if (client->parse_device(device)) {
         found = true;
       }
     }
+#endif
 
     if (!found && !this->scan_continuous_) {
       this->print_bt_device_info(device);
@@ -749,8 +769,10 @@ void ESP32BLETracker::cleanup_scan_state_(bool is_stop_complete) {
   // Reset timeout state machine instead of cancelling scheduler timeout
   this->scan_timeout_state_ = ScanTimeoutState::INACTIVE;
 
+#ifdef ESPHOME_ESP32_BLE_TRACKER_LISTENER_COUNT
   for (auto *listener : this->listeners_)
     listener->on_scan_end();
+#endif
 
   this->set_scanner_state_(ScannerState::IDLE);
 }
@@ -774,6 +796,7 @@ void ESP32BLETracker::handle_scanner_failure_() {
 
 void ESP32BLETracker::try_promote_discovered_clients_() {
   // Only promote the first discovered client to avoid multiple simultaneous connections
+#ifdef ESPHOME_ESP32_BLE_TRACKER_CLIENT_COUNT
   for (auto *client : this->clients_) {
     if (client->state() != ClientState::DISCOVERED) {
       continue;
@@ -795,6 +818,7 @@ void ESP32BLETracker::try_promote_discovered_clients_() {
     client->connect();
     break;
   }
+#endif
 }
 
 const char *ESP32BLETracker::scanner_state_to_string_(ScannerState state) const {

esphome/components/esp32_ble_tracker/esp32_ble_tracker.h

@@ -302,6 +302,7 @@ class ESP32BLETracker : public Component,
   /// Count clients in each state
   ClientStateCounts count_client_states_() const {
     ClientStateCounts counts;
+#ifdef ESPHOME_ESP32_BLE_TRACKER_CLIENT_COUNT
     for (auto *client : this->clients_) {
       switch (client->state()) {
         case ClientState::DISCONNECTING:
@@ -317,12 +318,17 @@ class ESP32BLETracker : public Component,
           break;
       }
     }
+#endif
     return counts;
   }
 
   // Group 1: Large objects (12+ bytes) - vectors and callback manager
-  std::vector<ESPBTDeviceListener *> listeners_;
-  std::vector<ESPBTClient *> clients_;
+#ifdef ESPHOME_ESP32_BLE_TRACKER_LISTENER_COUNT
+  StaticVector<ESPBTDeviceListener *, ESPHOME_ESP32_BLE_TRACKER_LISTENER_COUNT> listeners_;
+#endif
+#ifdef ESPHOME_ESP32_BLE_TRACKER_CLIENT_COUNT
+  StaticVector<ESPBTClient *, ESPHOME_ESP32_BLE_TRACKER_CLIENT_COUNT> clients_;
+#endif
   CallbackManager<void(ScannerState)> scanner_state_callbacks_;
 #ifdef USE_ESP32_BLE_DEVICE
   /// Vector of addresses that have already been printed in print_bt_device_info

esphome/components/esp32_improv/esp32_improv_component.cpp

@@ -143,6 +143,7 @@ void ESP32ImprovComponent::loop() {
 #else
       this->set_state_(improv::STATE_AUTHORIZED);
 #endif
+      this->check_wifi_connection_();
       break;
     }
     case improv::STATE_AUTHORIZED: {
@@ -156,31 +157,12 @@ void ESP32ImprovComponent::loop() {
       if (!this->check_identify_()) {
         this->set_status_indicator_state_((now % 1000) < 500);
       }
+      this->check_wifi_connection_();
       break;
     }
     case improv::STATE_PROVISIONING: {
       this->set_status_indicator_state_((now % 200) < 100);
-      if (wifi::global_wifi_component->is_connected()) {
-        wifi::global_wifi_component->save_wifi_sta(this->connecting_sta_.get_ssid(),
-                                                   this->connecting_sta_.get_password());
-        this->connecting_sta_ = {};
-        this->cancel_timeout("wifi-connect-timeout");
-        this->set_state_(improv::STATE_PROVISIONED);
-
-        std::vector<std::string> urls = {ESPHOME_MY_LINK};
-#ifdef USE_WEBSERVER
-        for (auto &ip : wifi::global_wifi_component->wifi_sta_ip_addresses()) {
-          if (ip.is_ip4()) {
-            std::string webserver_url = "http://" + ip.str() + ":" + to_string(USE_WEBSERVER_PORT);
-            urls.push_back(webserver_url);
-            break;
-          }
-        }
-#endif
-        std::vector<uint8_t> data = improv::build_rpc_response(improv::WIFI_SETTINGS, urls);
-        this->send_response_(data);
-        this->stop();
-      }
+      this->check_wifi_connection_();
       break;
     }
     case improv::STATE_PROVISIONED: {
@@ -392,6 +374,36 @@ void ESP32ImprovComponent::on_wifi_connect_timeout_() {
   wifi::global_wifi_component->clear_sta();
 }
 
+void ESP32ImprovComponent::check_wifi_connection_() {
+  if (!wifi::global_wifi_component->is_connected()) {
+    return;
+  }
+
+  if (this->state_ == improv::STATE_PROVISIONING) {
+    wifi::global_wifi_component->save_wifi_sta(this->connecting_sta_.get_ssid(), this->connecting_sta_.get_password());
+    this->connecting_sta_ = {};
+    this->cancel_timeout("wifi-connect-timeout");
+
+    std::vector<std::string> urls = {ESPHOME_MY_LINK};
+#ifdef USE_WEBSERVER
+    for (auto &ip : wifi::global_wifi_component->wifi_sta_ip_addresses()) {
+      if (ip.is_ip4()) {
+        std::string webserver_url = "http://" + ip.str() + ":" + to_string(USE_WEBSERVER_PORT);
+        urls.push_back(webserver_url);
+        break;
+      }
+    }
+#endif
+    std::vector<uint8_t> data = improv::build_rpc_response(improv::WIFI_SETTINGS, urls);
+    this->send_response_(data);
+  } else if (this->is_active() && this->state_ != improv::STATE_PROVISIONED) {
+    ESP_LOGD(TAG, "WiFi provisioned externally");
+  }
+
+  this->set_state_(improv::STATE_PROVISIONED);
+  this->stop();
+}
+
 void ESP32ImprovComponent::advertise_service_data_() {
   uint8_t service_data[IMPROV_SERVICE_DATA_SIZE] = {};
   service_data[0] = IMPROV_PROTOCOL_ID_1;  // PR

esphome/components/esp32_improv/esp32_improv_component.h

@@ -111,6 +111,7 @@ class ESP32ImprovComponent : public Component {
   void send_response_(std::vector<uint8_t> &response);
   void process_incoming_data_();
   void on_wifi_connect_timeout_();
+  void check_wifi_connection_();
   bool check_identify_();
   void advertise_service_data_();
 #if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_DEBUG

esphome/components/esphome/ota/ota_esphome.cpp

@@ -29,7 +29,7 @@ namespace esphome {
 static const char *const TAG = "esphome.ota";
 static constexpr uint16_t OTA_BLOCK_SIZE = 8192;
 static constexpr size_t OTA_BUFFER_SIZE = 1024;                  // buffer size for OTA data transfer
-static constexpr uint32_t OTA_SOCKET_TIMEOUT_HANDSHAKE = 10000;  // milliseconds for initial handshake
+static constexpr uint32_t OTA_SOCKET_TIMEOUT_HANDSHAKE = 20000;  // milliseconds for initial handshake
 static constexpr uint32_t OTA_SOCKET_TIMEOUT_DATA = 90000;       // milliseconds for data transfer
 
 #ifdef USE_OTA_PASSWORD

esphome/components/ethernet/ethernet_component.cpp

@@ -691,7 +691,9 @@ void EthernetComponent::set_manual_ip(const ManualIP &manual_ip) { this->manual_
 
 std::string EthernetComponent::get_use_address() const {
   if (this->use_address_.empty()) {
-    return App.get_name() + ".local";
+    // ".local" suffix length for mDNS hostnames
+    constexpr size_t mdns_local_suffix_len = 5;
+    return make_name_with_suffix(App.get_name(), '.', "local", mdns_local_suffix_len);
   }
   return this->use_address_;
 }

esphome/components/http_request/http_request.h

@@ -167,8 +167,8 @@ class HttpRequestComponent : public Component {
   }
 
  protected:
-  virtual std::shared_ptr<HttpContainer> perform(std::string url, std::string method, std::string body,
-                                                 std::list<Header> request_headers,
+  virtual std::shared_ptr<HttpContainer> perform(const std::string &url, const std::string &method,
+                                                 const std::string &body, const std::list<Header> &request_headers,
                                                  std::set<std::string> collect_headers) = 0;
   const char *useragent_{nullptr};
   bool follow_redirects_{};

esphome/components/http_request/http_request_arduino.cpp

@@ -14,8 +14,9 @@ namespace http_request {
 
 static const char *const TAG = "http_request.arduino";
 
-std::shared_ptr<HttpContainer> HttpRequestArduino::perform(std::string url, std::string method, std::string body,
-                                                           std::list<Header> request_headers,
+std::shared_ptr<HttpContainer> HttpRequestArduino::perform(const std::string &url, const std::string &method,
+                                                           const std::string &body,
+                                                           const std::list<Header> &request_headers,
                                                            std::set<std::string> collect_headers) {
   if (!network::is_connected()) {
     this->status_momentary_error("failed", 1000);

esphome/components/http_request/http_request_arduino.h

@@ -31,8 +31,8 @@ class HttpContainerArduino : public HttpContainer {
 
 class HttpRequestArduino : public HttpRequestComponent {
  protected:
-  std::shared_ptr<HttpContainer> perform(std::string url, std::string method, std::string body,
-                                         std::list<Header> request_headers,
+  std::shared_ptr<HttpContainer> perform(const std::string &url, const std::string &method, const std::string &body,
+                                         const std::list<Header> &request_headers,
                                          std::set<std::string> collect_headers) override;
 };
 

esphome/components/http_request/http_request_host.cpp

@@ -17,8 +17,9 @@ namespace http_request {
 
 static const char *const TAG = "http_request.host";
 
-std::shared_ptr<HttpContainer> HttpRequestHost::perform(std::string url, std::string method, std::string body,
-                                                        std::list<Header> request_headers,
+std::shared_ptr<HttpContainer> HttpRequestHost::perform(const std::string &url, const std::string &method,
+                                                        const std::string &body,
+                                                        const std::list<Header> &request_headers,
                                                         std::set<std::string> response_headers) {
   if (!network::is_connected()) {
     this->status_momentary_error("failed", 1000);

esphome/components/http_request/http_request_host.h

@@ -18,8 +18,8 @@ class HttpContainerHost : public HttpContainer {
 
 class HttpRequestHost : public HttpRequestComponent {
  public:
-  std::shared_ptr<HttpContainer> perform(std::string url, std::string method, std::string body,
-                                         std::list<Header> request_headers,
+  std::shared_ptr<HttpContainer> perform(const std::string &url, const std::string &method, const std::string &body,
+                                         const std::list<Header> &request_headers,
                                          std::set<std::string> response_headers) override;
   void set_ca_path(const char *ca_path) { this->ca_path_ = ca_path; }
 

esphome/components/http_request/http_request_idf.cpp

@@ -52,8 +52,9 @@ esp_err_t HttpRequestIDF::http_event_handler(esp_http_client_event_t *evt) {
   return ESP_OK;
 }
 
-std::shared_ptr<HttpContainer> HttpRequestIDF::perform(std::string url, std::string method, std::string body,
-                                                       std::list<Header> request_headers,
+std::shared_ptr<HttpContainer> HttpRequestIDF::perform(const std::string &url, const std::string &method,
+                                                       const std::string &body,
+                                                       const std::list<Header> &request_headers,
                                                        std::set<std::string> collect_headers) {
   if (!network::is_connected()) {
     this->status_momentary_error("failed", 1000);

esphome/components/http_request/http_request_idf.h

@@ -37,8 +37,8 @@ class HttpRequestIDF : public HttpRequestComponent {
   void set_buffer_size_tx(uint16_t buffer_size_tx) { this->buffer_size_tx_ = buffer_size_tx; }
 
  protected:
-  std::shared_ptr<HttpContainer> perform(std::string url, std::string method, std::string body,
-                                         std::list<Header> request_headers,
+  std::shared_ptr<HttpContainer> perform(const std::string &url, const std::string &method, const std::string &body,
+                                         const std::list<Header> &request_headers,
                                          std::set<std::string> collect_headers) override;
   // if zero ESP-IDF will use DEFAULT_HTTP_BUF_SIZE
   uint16_t buffer_size_rx_{};

esphome/components/json/json_util.cpp

@@ -8,6 +8,13 @@ namespace json {
 
 static const char *const TAG = "json";
 
+#ifdef USE_PSRAM
+// Global allocator that outlives all JsonDocuments returned by parse_json()
+// This prevents dangling pointer issues when JsonDocuments are returned from functions
+// NOLINTNEXTLINE(cppcoreguidelines-avoid-non-const-global-variables) - Must be mutable for ArduinoJson::Allocator
+static SpiRamAllocator global_json_allocator;
+#endif
+
 std::string build_json(const json_build_t &f) {
   // NOLINTBEGIN(clang-analyzer-cplusplus.NewDeleteLeaks) false positive with ArduinoJson
   JsonBuilder builder;
@@ -33,8 +40,7 @@ JsonDocument parse_json(const uint8_t *data, size_t len) {
     return JsonObject();  // return unbound object
   }
 #ifdef USE_PSRAM
-  auto doc_allocator = SpiRamAllocator();
-  JsonDocument json_document(&doc_allocator);
+  JsonDocument json_document(&global_json_allocator);
 #else
   JsonDocument json_document;
 #endif

esphome/components/mcp23xxx_base/mcp23xxx_base.h

@@ -21,11 +21,11 @@ template<uint8_t N> class MCP23XXXBase : public Component, public gpio_expander:
 
  protected:
   // read a given register
-  virtual bool read_reg(uint8_t reg, uint8_t *value);
+  virtual bool read_reg(uint8_t reg, uint8_t *value) = 0;
   // write a value to a given register
-  virtual bool write_reg(uint8_t reg, uint8_t value);
+  virtual bool write_reg(uint8_t reg, uint8_t value) = 0;
   // update registers with given pin value.
-  virtual void update_reg(uint8_t pin, bool pin_value, uint8_t reg_a);
+  virtual void update_reg(uint8_t pin, bool pin_value, uint8_t reg_a) = 0;
 
   bool open_drain_ints_;
 };

esphome/components/mdns/__init__.py

@@ -1,6 +1,6 @@
 import esphome.codegen as cg
 from esphome.components.esp32 import add_idf_component
-from esphome.config_helpers import filter_source_files_from_platform
+from esphome.config_helpers import filter_source_files_from_platform, get_logger_level
 import esphome.config_validation as cv
 from esphome.const import (
     CONF_DISABLED,
@@ -11,7 +11,7 @@ from esphome.const import (
     CONF_SERVICES,
     PlatformFramework,
 )
-from esphome.core import CORE, coroutine_with_priority
+from esphome.core import CORE, Lambda, coroutine_with_priority
 from esphome.coroutine import CoroPriority
 
 CODEOWNERS = ["@esphome/core"]
@@ -58,26 +58,84 @@ CONFIG_SCHEMA = cv.All(
 )
 
 
-def mdns_txt_record(key: str, value: str):
-    return cg.StructInitializer(
-        MDNSTXTRecord,
-        ("key", key),
-        ("value", value),
+def mdns_txt_record(key: str, value: str) -> cg.RawExpression:
+    """Create a mDNS TXT record.
+
+    Public API for external components. Do not remove.
+
+    Args:
+        key: The TXT record key
+        value: The TXT record value (static string only)
+
+    Returns:
+        A RawExpression representing a MDNSTXTRecord struct
+    """
+    return cg.RawExpression(
+        f"{{MDNS_STR({cg.safe_exp(key)}), MDNS_STR({cg.safe_exp(value)})}}"
     )
 
 
+async def _mdns_txt_record_templated(
+    mdns_comp: cg.Pvariable, key: str, value: Lambda | str
+) -> cg.RawExpression:
+    """Create a mDNS TXT record with support for templated values.
+
+    Internal helper function.
+
+    Args:
+        mdns_comp: The MDNSComponent instance (from cg.get_variable())
+        key: The TXT record key
+        value: The TXT record value (can be a static string or a lambda template)
+
+    Returns:
+        A RawExpression representing a MDNSTXTRecord struct
+    """
+    if not cg.is_template(value):
+        # It's a static string - use directly in flash, no need to store in vector
+        return mdns_txt_record(key, value)
+    # It's a lambda - evaluate and store using helper
+    templated_value = await cg.templatable(value, [], cg.std_string)
+    safe_key = cg.safe_exp(key)
+    dynamic_call = f"{mdns_comp}->add_dynamic_txt_value(({templated_value})())"
+    return cg.RawExpression(f"{{MDNS_STR({safe_key}), MDNS_STR({dynamic_call})}}")
+
+
 def mdns_service(
-    service: str, proto: str, port: int, txt_records: list[dict[str, str]]
-):
+    service: str, proto: str, port: int, txt_records: list[cg.RawExpression]
+) -> cg.StructInitializer:
+    """Create a mDNS service.
+
+    Public API for external components. Do not remove.
+
+    Args:
+        service: Service name (e.g., "_http")
+        proto: Protocol (e.g., "_tcp" or "_udp")
+        port: Port number
+        txt_records: List of MDNSTXTRecord expressions
+
+    Returns:
+        A StructInitializer representing a MDNSService struct
+    """
     return cg.StructInitializer(
         MDNSService,
-        ("service_type", service),
-        ("proto", proto),
+        ("service_type", cg.RawExpression(f"MDNS_STR({cg.safe_exp(service)})")),
+        ("proto", cg.RawExpression(f"MDNS_STR({cg.safe_exp(proto)})")),
         ("port", port),
         ("txt_records", txt_records),
     )
 
 
+def enable_mdns_storage():
+    """Enable persistent storage of mDNS services in the MDNSComponent.
+
+    Called by external components (like OpenThread) that need access to
+    services after setup() completes via get_services().
+
+    Public API for external components. Do not remove.
+    """
+    cg.add_define("USE_MDNS_STORE_SERVICES")
+
+
 @coroutine_with_priority(CoroPriority.NETWORK_SERVICES)
 async def to_code(config):
     if config[CONF_DISABLED] is True:
@@ -103,27 +161,47 @@ async def to_code(config):
 
     if config[CONF_SERVICES]:
         cg.add_define("USE_MDNS_EXTRA_SERVICES")
+        # Extra services need to be stored persistently
+        enable_mdns_storage()
 
     # Ensure at least 1 service (fallback service)
     cg.add_define("MDNS_SERVICE_COUNT", max(1, service_count))
 
+    # Calculate compile-time dynamic TXT value count
+    # Dynamic values are those that cannot be stored in flash at compile time
+    dynamic_txt_count = 0
+    if "api" in CORE.config:
+        # Always: get_mac_address()
+        dynamic_txt_count += 1
+    # User-provided templatable TXT values (only lambdas, not static strings)
+    dynamic_txt_count += sum(
+        1
+        for service in config[CONF_SERVICES]
+        for txt_value in service[CONF_TXT].values()
+        if cg.is_template(txt_value)
+    )
+
+    # Ensure at least 1 to avoid zero-size array
+    cg.add_define("MDNS_DYNAMIC_TXT_COUNT", max(1, dynamic_txt_count))
+
+    # Enable storage if verbose logging is enabled (for dump_config)
+    if get_logger_level() in ("VERBOSE", "VERY_VERBOSE"):
+        enable_mdns_storage()
+
     var = cg.new_Pvariable(config[CONF_ID])
     await cg.register_component(var, config)
 
     for service in config[CONF_SERVICES]:
-        txt = [
-            cg.StructInitializer(
-                MDNSTXTRecord,
-                ("key", txt_key),
-                ("value", await cg.templatable(txt_value, [], cg.std_string)),
-            )
+        txt_records = [
+            await _mdns_txt_record_templated(var, txt_key, txt_value)
             for txt_key, txt_value in service[CONF_TXT].items()
         ]
+
         exp = mdns_service(
             service[CONF_SERVICE],
             service[CONF_PROTOCOL],
             await cg.templatable(service[CONF_PORT], [], cg.uint16),
-            txt,
+            txt_records,
         )
 
         cg.add(var.add_extra_service(exp))

esphome/components/mdns/mdns_component.cpp

@@ -9,24 +9,9 @@
 #include <pgmspace.h>
 // Macro to define strings in PROGMEM on ESP8266, regular memory on other platforms
 #define MDNS_STATIC_CONST_CHAR(name, value) static const char name[] PROGMEM = value
-// Helper to get string from PROGMEM - returns a temporary std::string
-// Only define this function if we have services that will use it
-#if defined(USE_API) || defined(USE_PROMETHEUS) || defined(USE_WEBSERVER) || defined(USE_MDNS_EXTRA_SERVICES)
-static std::string mdns_string_p(const char *src) {
-  char buf[64];
-  strncpy_P(buf, src, sizeof(buf) - 1);
-  buf[sizeof(buf) - 1] = '\0';
-  return std::string(buf);
-}
-#define MDNS_STR(name) mdns_string_p(name)
-#else
-// If no services are configured, we still need the fallback service but it uses string literals
-#define MDNS_STR(name) std::string(name)
-#endif
 #else
 // On non-ESP8266 platforms, use regular const char*
-#define MDNS_STATIC_CONST_CHAR(name, value) static constexpr const char *name = value
-#define MDNS_STR(name) name
+#define MDNS_STATIC_CONST_CHAR(name, value) static constexpr const char name[] = value
 #endif
 
 #ifdef USE_API
@@ -46,40 +31,29 @@ static const char *const TAG = "mdns";
 #endif
 
 // Define all constant strings using the macro
-MDNS_STATIC_CONST_CHAR(SERVICE_ESPHOMELIB, "_esphomelib");
 MDNS_STATIC_CONST_CHAR(SERVICE_TCP, "_tcp");
-MDNS_STATIC_CONST_CHAR(SERVICE_PROMETHEUS, "_prometheus-http");
-MDNS_STATIC_CONST_CHAR(SERVICE_HTTP, "_http");
 
-MDNS_STATIC_CONST_CHAR(TXT_FRIENDLY_NAME, "friendly_name");
-MDNS_STATIC_CONST_CHAR(TXT_VERSION, "version");
-MDNS_STATIC_CONST_CHAR(TXT_MAC, "mac");
-MDNS_STATIC_CONST_CHAR(TXT_PLATFORM, "platform");
-MDNS_STATIC_CONST_CHAR(TXT_BOARD, "board");
-MDNS_STATIC_CONST_CHAR(TXT_NETWORK, "network");
-MDNS_STATIC_CONST_CHAR(TXT_API_ENCRYPTION, "api_encryption");
-MDNS_STATIC_CONST_CHAR(TXT_API_ENCRYPTION_SUPPORTED, "api_encryption_supported");
-MDNS_STATIC_CONST_CHAR(TXT_PROJECT_NAME, "project_name");
-MDNS_STATIC_CONST_CHAR(TXT_PROJECT_VERSION, "project_version");
-MDNS_STATIC_CONST_CHAR(TXT_PACKAGE_IMPORT_URL, "package_import_url");
+// Wrap build-time defines into flash storage
+MDNS_STATIC_CONST_CHAR(VALUE_VERSION, ESPHOME_VERSION);
 
-MDNS_STATIC_CONST_CHAR(PLATFORM_ESP8266, "ESP8266");
-MDNS_STATIC_CONST_CHAR(PLATFORM_ESP32, "ESP32");
-MDNS_STATIC_CONST_CHAR(PLATFORM_RP2040, "RP2040");
-
-MDNS_STATIC_CONST_CHAR(NETWORK_WIFI, "wifi");
-MDNS_STATIC_CONST_CHAR(NETWORK_ETHERNET, "ethernet");
-MDNS_STATIC_CONST_CHAR(NETWORK_THREAD, "thread");
-
-void MDNSComponent::compile_records_() {
+void MDNSComponent::compile_records_(StaticVector<MDNSService, MDNS_SERVICE_COUNT> &services) {
   this->hostname_ = App.get_name();
 
   // IMPORTANT: The #ifdef blocks below must match COMPONENTS_WITH_MDNS_SERVICES
   // in mdns/__init__.py. If you add a new service here, update both locations.
 
 #ifdef USE_API
+  MDNS_STATIC_CONST_CHAR(SERVICE_ESPHOMELIB, "_esphomelib");
+  MDNS_STATIC_CONST_CHAR(TXT_FRIENDLY_NAME, "friendly_name");
+  MDNS_STATIC_CONST_CHAR(TXT_VERSION, "version");
+  MDNS_STATIC_CONST_CHAR(TXT_MAC, "mac");
+  MDNS_STATIC_CONST_CHAR(TXT_PLATFORM, "platform");
+  MDNS_STATIC_CONST_CHAR(TXT_BOARD, "board");
+  MDNS_STATIC_CONST_CHAR(TXT_NETWORK, "network");
+  MDNS_STATIC_CONST_CHAR(VALUE_BOARD, ESPHOME_BOARD);
+
   if (api::global_api_server != nullptr) {
-    auto &service = this->services_.emplace_next();
+    auto &service = services.emplace_next();
     service.service_type = MDNS_STR(SERVICE_ESPHOMELIB);
     service.proto = MDNS_STR(SERVICE_TCP);
     service.port = api::global_api_server->get_port();
@@ -112,73 +86,97 @@ void MDNSComponent::compile_records_() {
     txt_records.reserve(txt_count);
 
     if (!friendly_name_empty) {
-      txt_records.push_back({MDNS_STR(TXT_FRIENDLY_NAME), friendly_name});
+      txt_records.push_back({MDNS_STR(TXT_FRIENDLY_NAME), MDNS_STR(friendly_name.c_str())});
     }
-    txt_records.push_back({MDNS_STR(TXT_VERSION), ESPHOME_VERSION});
-    txt_records.push_back({MDNS_STR(TXT_MAC), get_mac_address()});
+    txt_records.push_back({MDNS_STR(TXT_VERSION), MDNS_STR(VALUE_VERSION)});
+    txt_records.push_back({MDNS_STR(TXT_MAC), MDNS_STR(this->add_dynamic_txt_value(get_mac_address()))});
 
 #ifdef USE_ESP8266
+    MDNS_STATIC_CONST_CHAR(PLATFORM_ESP8266, "ESP8266");
     txt_records.push_back({MDNS_STR(TXT_PLATFORM), MDNS_STR(PLATFORM_ESP8266)});
 #elif defined(USE_ESP32)
+    MDNS_STATIC_CONST_CHAR(PLATFORM_ESP32, "ESP32");
     txt_records.push_back({MDNS_STR(TXT_PLATFORM), MDNS_STR(PLATFORM_ESP32)});
 #elif defined(USE_RP2040)
+    MDNS_STATIC_CONST_CHAR(PLATFORM_RP2040, "RP2040");
     txt_records.push_back({MDNS_STR(TXT_PLATFORM), MDNS_STR(PLATFORM_RP2040)});
 #elif defined(USE_LIBRETINY)
-    txt_records.emplace_back(MDNSTXTRecord{"platform", lt_cpu_get_model_name()});
+    txt_records.push_back({MDNS_STR(TXT_PLATFORM), MDNS_STR(lt_cpu_get_model_name())});
 #endif
 
-    txt_records.push_back({MDNS_STR(TXT_BOARD), ESPHOME_BOARD});
+    txt_records.push_back({MDNS_STR(TXT_BOARD), MDNS_STR(VALUE_BOARD)});
 
 #if defined(USE_WIFI)
+    MDNS_STATIC_CONST_CHAR(NETWORK_WIFI, "wifi");
     txt_records.push_back({MDNS_STR(TXT_NETWORK), MDNS_STR(NETWORK_WIFI)});
 #elif defined(USE_ETHERNET)
+    MDNS_STATIC_CONST_CHAR(NETWORK_ETHERNET, "ethernet");
     txt_records.push_back({MDNS_STR(TXT_NETWORK), MDNS_STR(NETWORK_ETHERNET)});
 #elif defined(USE_OPENTHREAD)
+    MDNS_STATIC_CONST_CHAR(NETWORK_THREAD, "thread");
     txt_records.push_back({MDNS_STR(TXT_NETWORK), MDNS_STR(NETWORK_THREAD)});
 #endif
 
 #ifdef USE_API_NOISE
+    MDNS_STATIC_CONST_CHAR(TXT_API_ENCRYPTION, "api_encryption");
+    MDNS_STATIC_CONST_CHAR(TXT_API_ENCRYPTION_SUPPORTED, "api_encryption_supported");
     MDNS_STATIC_CONST_CHAR(NOISE_ENCRYPTION, "Noise_NNpsk0_25519_ChaChaPoly_SHA256");
-    if (api::global_api_server->get_noise_ctx()->has_psk()) {
-      txt_records.push_back({MDNS_STR(TXT_API_ENCRYPTION), MDNS_STR(NOISE_ENCRYPTION)});
-    } else {
-      txt_records.push_back({MDNS_STR(TXT_API_ENCRYPTION_SUPPORTED), MDNS_STR(NOISE_ENCRYPTION)});
-    }
+    bool has_psk = api::global_api_server->get_noise_ctx()->has_psk();
+    const char *encryption_key = has_psk ? TXT_API_ENCRYPTION : TXT_API_ENCRYPTION_SUPPORTED;
+    txt_records.push_back({MDNS_STR(encryption_key), MDNS_STR(NOISE_ENCRYPTION)});
 #endif
 
 #ifdef ESPHOME_PROJECT_NAME
-    txt_records.push_back({MDNS_STR(TXT_PROJECT_NAME), ESPHOME_PROJECT_NAME});
-    txt_records.push_back({MDNS_STR(TXT_PROJECT_VERSION), ESPHOME_PROJECT_VERSION});
+    MDNS_STATIC_CONST_CHAR(TXT_PROJECT_NAME, "project_name");
+    MDNS_STATIC_CONST_CHAR(TXT_PROJECT_VERSION, "project_version");
+    MDNS_STATIC_CONST_CHAR(VALUE_PROJECT_NAME, ESPHOME_PROJECT_NAME);
+    MDNS_STATIC_CONST_CHAR(VALUE_PROJECT_VERSION, ESPHOME_PROJECT_VERSION);
+    txt_records.push_back({MDNS_STR(TXT_PROJECT_NAME), MDNS_STR(VALUE_PROJECT_NAME)});
+    txt_records.push_back({MDNS_STR(TXT_PROJECT_VERSION), MDNS_STR(VALUE_PROJECT_VERSION)});
 #endif  // ESPHOME_PROJECT_NAME
 
 #ifdef USE_DASHBOARD_IMPORT
-    txt_records.push_back({MDNS_STR(TXT_PACKAGE_IMPORT_URL), dashboard_import::get_package_import_url()});
+    MDNS_STATIC_CONST_CHAR(TXT_PACKAGE_IMPORT_URL, "package_import_url");
+    txt_records.push_back(
+        {MDNS_STR(TXT_PACKAGE_IMPORT_URL), MDNS_STR(dashboard_import::get_package_import_url().c_str())});
 #endif
   }
 #endif  // USE_API
 
 #ifdef USE_PROMETHEUS
-  auto &prom_service = this->services_.emplace_next();
+  MDNS_STATIC_CONST_CHAR(SERVICE_PROMETHEUS, "_prometheus-http");
+
+  auto &prom_service = services.emplace_next();
   prom_service.service_type = MDNS_STR(SERVICE_PROMETHEUS);
   prom_service.proto = MDNS_STR(SERVICE_TCP);
   prom_service.port = USE_WEBSERVER_PORT;
 #endif
 
 #ifdef USE_WEBSERVER
-  auto &web_service = this->services_.emplace_next();
+  MDNS_STATIC_CONST_CHAR(SERVICE_HTTP, "_http");
+
+  auto &web_service = services.emplace_next();
   web_service.service_type = MDNS_STR(SERVICE_HTTP);
   web_service.proto = MDNS_STR(SERVICE_TCP);
   web_service.port = USE_WEBSERVER_PORT;
 #endif
 
 #if !defined(USE_API) && !defined(USE_PROMETHEUS) && !defined(USE_WEBSERVER) && !defined(USE_MDNS_EXTRA_SERVICES)
+  MDNS_STATIC_CONST_CHAR(SERVICE_HTTP, "_http");
+  MDNS_STATIC_CONST_CHAR(TXT_VERSION, "version");
+
   // Publish "http" service if not using native API or any other services
   // This is just to have *some* mDNS service so that .local resolution works
-  auto &fallback_service = this->services_.emplace_next();
-  fallback_service.service_type = "_http";
-  fallback_service.proto = "_tcp";
+  auto &fallback_service = services.emplace_next();
+  fallback_service.service_type = MDNS_STR(SERVICE_HTTP);
+  fallback_service.proto = MDNS_STR(SERVICE_TCP);
   fallback_service.port = USE_WEBSERVER_PORT;
-  fallback_service.txt_records.emplace_back(MDNSTXTRecord{"version", ESPHOME_VERSION});
+  fallback_service.txt_records.push_back({MDNS_STR(TXT_VERSION), MDNS_STR(VALUE_VERSION)});
+#endif
+
+#ifdef USE_MDNS_STORE_SERVICES
+  // Copy to member variable if storage is enabled (verbose logging, OpenThread, or extra services)
+  this->services_ = services;
 #endif
 }
 
@@ -187,14 +185,13 @@ void MDNSComponent::dump_config() {
                 "mDNS:\n"
                 "  Hostname: %s",
                 this->hostname_.c_str());
-#if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
+#ifdef USE_MDNS_STORE_SERVICES
   ESP_LOGV(TAG, "  Services:");
   for (const auto &service : this->services_) {
-    ESP_LOGV(TAG, "  - %s, %s, %d", service.service_type.c_str(), service.proto.c_str(),
+    ESP_LOGV(TAG, "  - %s, %s, %d", MDNS_STR_ARG(service.service_type), MDNS_STR_ARG(service.proto),
              const_cast<TemplatableValue<uint16_t> &>(service.port).value());
     for (const auto &record : service.txt_records) {
-      ESP_LOGV(TAG, "    TXT: %s = %s", record.key.c_str(),
-               const_cast<TemplatableValue<std::string> &>(record.value).value().c_str());
+      ESP_LOGV(TAG, "    TXT: %s = %s", MDNS_STR_ARG(record.key), MDNS_STR_ARG(record.value));
     }
   }
 #endif

esphome/components/mdns/mdns_component.h

@@ -9,21 +9,34 @@
 namespace esphome {
 namespace mdns {
 
+// Helper struct that identifies strings that may be stored in flash storage (similar to LogString)
+struct MDNSString;
+
+// Macro to cast string literals to MDNSString* (works on all platforms)
+#define MDNS_STR(name) (reinterpret_cast<const esphome::mdns::MDNSString *>(name))
+
+#ifdef USE_ESP8266
+#include <pgmspace.h>
+#define MDNS_STR_ARG(s) ((PGM_P) (s))
+#else
+#define MDNS_STR_ARG(s) (reinterpret_cast<const char *>(s))
+#endif
+
 // Service count is calculated at compile time by Python codegen
 // MDNS_SERVICE_COUNT will always be defined
 
 struct MDNSTXTRecord {
-  std::string key;
-  TemplatableValue<std::string> value;
+  const MDNSString *key;
+  const MDNSString *value;
 };
 
 struct MDNSService {
   // service name _including_ underscore character prefix
   // as defined in RFC6763 Section 7
-  std::string service_type;
+  const MDNSString *service_type;
   // second label indicating protocol _including_ underscore character prefix
   // as defined in RFC6763 Section 7, like "_tcp" or "_udp"
-  std::string proto;
+  const MDNSString *proto;
   TemplatableValue<uint16_t> port;
   std::vector<MDNSTXTRecord> txt_records;
 };
@@ -42,14 +55,29 @@ class MDNSComponent : public Component {
   void add_extra_service(MDNSService service) { this->services_.emplace_next() = std::move(service); }
 #endif
 
+#ifdef USE_MDNS_STORE_SERVICES
   const StaticVector<MDNSService, MDNS_SERVICE_COUNT> &get_services() const { return this->services_; }
+#endif
 
   void on_shutdown() override;
 
+  /// Add a dynamic TXT value and return pointer to it for use in MDNSTXTRecord
+  const char *add_dynamic_txt_value(const std::string &value) {
+    this->dynamic_txt_values_.push_back(value);
+    return this->dynamic_txt_values_[this->dynamic_txt_values_.size() - 1].c_str();
+  }
+
+  /// Storage for runtime-generated TXT values (MAC address, user lambdas)
+  /// Pre-sized at compile time via MDNS_DYNAMIC_TXT_COUNT to avoid heap allocations.
+  /// Static/compile-time values (version, board, etc.) are stored directly in flash and don't use this.
+  StaticVector<std::string, MDNS_DYNAMIC_TXT_COUNT> dynamic_txt_values_;
+
  protected:
+#ifdef USE_MDNS_STORE_SERVICES
   StaticVector<MDNSService, MDNS_SERVICE_COUNT> services_{};
+#endif
   std::string hostname_;
-  void compile_records_();
+  void compile_records_(StaticVector<MDNSService, MDNS_SERVICE_COUNT> &services);
 };
 
 }  // namespace mdns

esphome/components/mdns/mdns_esp32.cpp

@@ -2,7 +2,6 @@
 #if defined(USE_ESP32) && defined(USE_MDNS)
 
 #include <mdns.h>
-#include <cstring>
 #include "esphome/core/hal.h"
 #include "esphome/core/log.h"
 #include "mdns_component.h"
@@ -13,7 +12,8 @@ namespace mdns {
 static const char *const TAG = "mdns";
 
 void MDNSComponent::setup() {
-  this->compile_records_();
+  StaticVector<MDNSService, MDNS_SERVICE_COUNT> services;
+  this->compile_records_(services);
 
   esp_err_t err = mdns_init();
   if (err != ESP_OK) {
@@ -25,19 +25,22 @@ void MDNSComponent::setup() {
   mdns_hostname_set(this->hostname_.c_str());
   mdns_instance_name_set(this->hostname_.c_str());
 
-  for (const auto &service : this->services_) {
-    std::vector<mdns_txt_item_t> txt_records(service.txt_records.size());
-    for (size_t i = 0; i < service.txt_records.size(); i++) {
-      // mdns_service_add copies the strings internally, no need to strdup
-      txt_records[i].key = service.txt_records[i].key.c_str();
-      txt_records[i].value = const_cast<TemplatableValue<std::string> &>(service.txt_records[i].value).value().c_str();
+  for (const auto &service : services) {
+    std::vector<mdns_txt_item_t> txt_records;
+    for (const auto &record : service.txt_records) {
+      mdns_txt_item_t it{};
+      // key and value are either compile-time string literals in flash or pointers to dynamic_txt_values_
+      // Both remain valid for the lifetime of this function, and ESP-IDF makes internal copies
+      it.key = MDNS_STR_ARG(record.key);
+      it.value = MDNS_STR_ARG(record.value);
+      txt_records.push_back(it);
     }
     uint16_t port = const_cast<TemplatableValue<uint16_t> &>(service.port).value();
-    err = mdns_service_add(nullptr, service.service_type.c_str(), service.proto.c_str(), port, txt_records.data(),
-                           txt_records.size());
+    err = mdns_service_add(nullptr, MDNS_STR_ARG(service.service_type), MDNS_STR_ARG(service.proto), port,
+                           txt_records.data(), txt_records.size());
 
     if (err != ESP_OK) {
-      ESP_LOGW(TAG, "Failed to register service %s: %s", service.service_type.c_str(), esp_err_to_name(err));
+      ESP_LOGW(TAG, "Failed to register service %s: %s", MDNS_STR_ARG(service.service_type), esp_err_to_name(err));
     }
   }
 }

esphome/components/mdns/mdns_esp8266.cpp

@@ -12,28 +12,29 @@ namespace esphome {
 namespace mdns {
 
 void MDNSComponent::setup() {
-  this->compile_records_();
+  StaticVector<MDNSService, MDNS_SERVICE_COUNT> services;
+  this->compile_records_(services);
 
   MDNS.begin(this->hostname_.c_str());
 
-  for (const auto &service : this->services_) {
+  for (const auto &service : services) {
     // Strip the leading underscore from the proto and service_type. While it is
     // part of the wire protocol to have an underscore, and for example ESP-IDF
     // expects the underscore to be there, the ESP8266 implementation always adds
     // the underscore itself.
-    auto *proto = service.proto.c_str();
-    while (*proto == '_') {
+    auto *proto = MDNS_STR_ARG(service.proto);
+    while (progmem_read_byte((const uint8_t *) proto) == '_') {
       proto++;
     }
-    auto *service_type = service.service_type.c_str();
-    while (*service_type == '_') {
+    auto *service_type = MDNS_STR_ARG(service.service_type);
+    while (progmem_read_byte((const uint8_t *) service_type) == '_') {
       service_type++;
     }
     uint16_t port = const_cast<TemplatableValue<uint16_t> &>(service.port).value();
-    MDNS.addService(service_type, proto, port);
+    MDNS.addService(FPSTR(service_type), FPSTR(proto), port);
     for (const auto &record : service.txt_records) {
-      MDNS.addServiceTxt(service_type, proto, record.key.c_str(),
-                         const_cast<TemplatableValue<std::string> &>(record.value).value().c_str());
+      MDNS.addServiceTxt(FPSTR(service_type), FPSTR(proto), FPSTR(MDNS_STR_ARG(record.key)),
+                         FPSTR(MDNS_STR_ARG(record.value)));
     }
   }
 }

esphome/components/mdns/mdns_host.cpp

@@ -9,7 +9,9 @@
 namespace esphome {
 namespace mdns {
 
-void MDNSComponent::setup() { this->compile_records_(); }
+void MDNSComponent::setup() {
+  // Host platform doesn't have actual mDNS implementation
+}
 
 void MDNSComponent::on_shutdown() {}
 

esphome/components/mdns/mdns_libretiny.cpp

@@ -12,28 +12,28 @@ namespace esphome {
 namespace mdns {
 
 void MDNSComponent::setup() {
-  this->compile_records_();
+  StaticVector<MDNSService, MDNS_SERVICE_COUNT> services;
+  this->compile_records_(services);
 
   MDNS.begin(this->hostname_.c_str());
 
-  for (const auto &service : this->services_) {
+  for (const auto &service : services) {
     // Strip the leading underscore from the proto and service_type. While it is
     // part of the wire protocol to have an underscore, and for example ESP-IDF
     // expects the underscore to be there, the ESP8266 implementation always adds
     // the underscore itself.
-    auto *proto = service.proto.c_str();
+    auto *proto = MDNS_STR_ARG(service.proto);
     while (*proto == '_') {
       proto++;
     }
-    auto *service_type = service.service_type.c_str();
+    auto *service_type = MDNS_STR_ARG(service.service_type);
     while (*service_type == '_') {
       service_type++;
     }
     uint16_t port_ = const_cast<TemplatableValue<uint16_t> &>(service.port).value();
     MDNS.addService(service_type, proto, port_);
     for (const auto &record : service.txt_records) {
-      MDNS.addServiceTxt(service_type, proto, record.key.c_str(),
-                         const_cast<TemplatableValue<std::string> &>(record.value).value().c_str());
+      MDNS.addServiceTxt(service_type, proto, MDNS_STR_ARG(record.key), MDNS_STR_ARG(record.value));
     }
   }
 }

esphome/components/mdns/mdns_rp2040.cpp

@@ -12,28 +12,28 @@ namespace esphome {
 namespace mdns {
 
 void MDNSComponent::setup() {
-  this->compile_records_();
+  StaticVector<MDNSService, MDNS_SERVICE_COUNT> services;
+  this->compile_records_(services);
 
   MDNS.begin(this->hostname_.c_str());
 
-  for (const auto &service : this->services_) {
+  for (const auto &service : services) {
     // Strip the leading underscore from the proto and service_type. While it is
     // part of the wire protocol to have an underscore, and for example ESP-IDF
     // expects the underscore to be there, the ESP8266 implementation always adds
     // the underscore itself.
-    auto *proto = service.proto.c_str();
+    auto *proto = MDNS_STR_ARG(service.proto);
     while (*proto == '_') {
       proto++;
     }
-    auto *service_type = service.service_type.c_str();
+    auto *service_type = MDNS_STR_ARG(service.service_type);
     while (*service_type == '_') {
       service_type++;
     }
     uint16_t port = const_cast<TemplatableValue<uint16_t> &>(service.port).value();
     MDNS.addService(service_type, proto, port);
     for (const auto &record : service.txt_records) {
-      MDNS.addServiceTxt(service_type, proto, record.key.c_str(),
-                         const_cast<TemplatableValue<std::string> &>(record.value).value().c_str());
+      MDNS.addServiceTxt(service_type, proto, MDNS_STR_ARG(record.key), MDNS_STR_ARG(record.value));
     }
   }
 }

esphome/components/modbus/modbus.cpp

@@ -66,7 +66,10 @@ bool Modbus::parse_modbus_byte_(uint8_t byte) {
   uint8_t data_offset = 3;
 
   // Per https://modbus.org/docs/Modbus_Application_Protocol_V1_1b3.pdf Ch 5 User-Defined function codes
-  if (((function_code >= 65) && (function_code <= 72)) || ((function_code >= 100) && (function_code <= 110))) {
+  if (((function_code >= FUNCTION_CODE_USER_DEFINED_SPACE_1_INIT) &&
+       (function_code <= FUNCTION_CODE_USER_DEFINED_SPACE_1_END)) ||
+      ((function_code >= FUNCTION_CODE_USER_DEFINED_SPACE_2_INIT) &&
+       (function_code <= FUNCTION_CODE_USER_DEFINED_SPACE_2_END))) {
     // Handle user-defined function, since we don't know how big this ought to be,
     // ideally we should delegate the entire length detection to whatever handler is
     // installed, but wait, there is the CRC, and if we get a hit there is a good
@@ -91,10 +94,14 @@ bool Modbus::parse_modbus_byte_(uint8_t byte) {
   } else {
     // data starts at 2 and length is 4 for read registers commands
     if (this->role == ModbusRole::SERVER) {
-      if (function_code == 0x1 || function_code == 0x3 || function_code == 0x4 || function_code == 0x6) {
+      if (function_code == ModbusFunctionCode::READ_COILS ||
+          function_code == ModbusFunctionCode::READ_DISCRETE_INPUTS ||
+          function_code == ModbusFunctionCode::READ_HOLDING_REGISTERS ||
+          function_code == ModbusFunctionCode::READ_INPUT_REGISTERS ||
+          function_code == ModbusFunctionCode::WRITE_SINGLE_REGISTER) {
         data_offset = 2;
         data_len = 4;
-      } else if (function_code == 0x10) {
+      } else if (function_code == ModbusFunctionCode::WRITE_MULTIPLE_REGISTERS) {
         if (at < 6) {
           return true;
         }
@@ -104,7 +111,10 @@ bool Modbus::parse_modbus_byte_(uint8_t byte) {
       }
     } else {
       // the response for write command mirrors the requests and data starts at offset 2 instead of 3 for read commands
-      if (function_code == 0x5 || function_code == 0x06 || function_code == 0xF || function_code == 0x10) {
+      if (function_code == ModbusFunctionCode::WRITE_SINGLE_COIL ||
+          function_code == ModbusFunctionCode::WRITE_SINGLE_REGISTER ||
+          function_code == ModbusFunctionCode::WRITE_MULTIPLE_COILS ||
+          function_code == ModbusFunctionCode::WRITE_MULTIPLE_REGISTERS) {
         data_offset = 2;
         data_len = 4;
       }
@@ -112,7 +122,7 @@ bool Modbus::parse_modbus_byte_(uint8_t byte) {
 
     // Error ( msb indicates error )
     // response format:  Byte[0] = device address, Byte[1] function code | 0x80 , Byte[2] exception code, Byte[3-4] crc
-    if ((function_code & 0x80) == 0x80) {
+    if ((function_code & FUNCTION_CODE_EXCEPTION_MASK) == FUNCTION_CODE_EXCEPTION_MASK) {
       data_offset = 2;
       data_len = 1;
     }
@@ -143,10 +153,10 @@ bool Modbus::parse_modbus_byte_(uint8_t byte) {
     if (device->address_ == address) {
       found = true;
       // Is it an error response?
-      if ((function_code & 0x80) == 0x80) {
+      if ((function_code & FUNCTION_CODE_EXCEPTION_MASK) == FUNCTION_CODE_EXCEPTION_MASK) {
         ESP_LOGD(TAG, "Modbus error function code: 0x%X exception: %d", function_code, raw[2]);
         if (waiting_for_response != 0) {
-          device->on_modbus_error(function_code & 0x7F, raw[2]);
+          device->on_modbus_error(function_code & FUNCTION_CODE_MASK, raw[2]);
         } else {
           // Ignore modbus exception not related to a pending command
           ESP_LOGD(TAG, "Ignoring Modbus error - not expecting a response");
@@ -154,12 +164,14 @@ bool Modbus::parse_modbus_byte_(uint8_t byte) {
         continue;
       }
       if (this->role == ModbusRole::SERVER) {
-        if (function_code == 0x3 || function_code == 0x4) {
+        if (function_code == ModbusFunctionCode::READ_HOLDING_REGISTERS ||
+            function_code == ModbusFunctionCode::READ_INPUT_REGISTERS) {
           device->on_modbus_read_registers(function_code, uint16_t(data[1]) | (uint16_t(data[0]) << 8),
                                            uint16_t(data[3]) | (uint16_t(data[2]) << 8));
           continue;
         }
-        if (function_code == 0x6 || function_code == 0x10) {
+        if (function_code == ModbusFunctionCode::WRITE_SINGLE_REGISTER ||
+            function_code == ModbusFunctionCode::WRITE_MULTIPLE_REGISTERS) {
           device->on_modbus_write_registers(function_code, data);
           continue;
         }
@@ -199,7 +211,7 @@ void Modbus::send(uint8_t address, uint8_t function_code, uint16_t start_address
 
   // Only check max number of registers for standard function codes
   // Some devices use non standard codes like 0x43
-  if (number_of_entities > MAX_VALUES && function_code <= 0x10) {
+  if (number_of_entities > MAX_VALUES && function_code <= ModbusFunctionCode::WRITE_MULTIPLE_REGISTERS) {
     ESP_LOGE(TAG, "send too many values %d max=%zu", number_of_entities, MAX_VALUES);
     return;
   }
@@ -210,15 +222,17 @@ void Modbus::send(uint8_t address, uint8_t function_code, uint16_t start_address
   if (this->role == ModbusRole::CLIENT) {
     data.push_back(start_address >> 8);
     data.push_back(start_address >> 0);
-    if (function_code != 0x5 && function_code != 0x6) {
+    if (function_code != ModbusFunctionCode::WRITE_SINGLE_COIL &&
+        function_code != ModbusFunctionCode::WRITE_SINGLE_REGISTER) {
       data.push_back(number_of_entities >> 8);
       data.push_back(number_of_entities >> 0);
     }
   }
 
   if (payload != nullptr) {
-    if (this->role == ModbusRole::SERVER || function_code == 0xF || function_code == 0x10) {  // Write multiple
-      data.push_back(payload_len);  // Byte count is required for write
+    if (this->role == ModbusRole::SERVER || function_code == ModbusFunctionCode::WRITE_MULTIPLE_COILS ||
+        function_code == ModbusFunctionCode::WRITE_MULTIPLE_REGISTERS) {  // Write multiple
+      data.push_back(payload_len);                                        // Byte count is required for write
     } else {
       payload_len = 2;  // Write single register or coil
     }

esphome/components/modbus/modbus.h

@@ -3,6 +3,8 @@
 #include "esphome/core/component.h"
 #include "esphome/components/uart/uart.h"
 
+#include "esphome/components/modbus/modbus_definitions.h"
+
 #include <vector>
 
 namespace esphome {
@@ -65,12 +67,12 @@ class ModbusDevice {
     this->parent_->send(this->address_, function, start_address, number_of_entities, payload_len, payload);
   }
   void send_raw(const std::vector<uint8_t> &payload) { this->parent_->send_raw(payload); }
-  void send_error(uint8_t function_code, uint8_t exception_code) {
+  void send_error(uint8_t function_code, ModbusExceptionCode exception_code) {
     std::vector<uint8_t> error_response;
     error_response.reserve(3);
     error_response.push_back(this->address_);
-    error_response.push_back(function_code | 0x80);
-    error_response.push_back(exception_code);
+    error_response.push_back(function_code | FUNCTION_CODE_EXCEPTION_MASK);
+    error_response.push_back(static_cast<uint8_t>(exception_code));
     this->send_raw(error_response);
   }
   // If more than one device is connected block sending a new command before a response is received

esphome/components/modbus/modbus_definitions.h

@@ -0,0 +1,86 @@
+#pragma once
+
+#include "esphome/core/component.h"
+
+namespace esphome {
+namespace modbus {
+
+/// Modbus definitions from specs:
+/// https://modbus.org/docs/Modbus_Application_Protocol_V1_1b3.pdf
+// 5 Function Code Categories
+const uint8_t FUNCTION_CODE_USER_DEFINED_SPACE_1_INIT = 65;  // 0x41
+const uint8_t FUNCTION_CODE_USER_DEFINED_SPACE_1_END = 72;   // 0x48
+
+const uint8_t FUNCTION_CODE_USER_DEFINED_SPACE_2_INIT = 100;  // 0x64
+const uint8_t FUNCTION_CODE_USER_DEFINED_SPACE_2_END = 110;   // 0x6E
+
+enum class ModbusFunctionCode : uint8_t {
+  CUSTOM = 0x00,
+  READ_COILS = 0x01,
+  READ_DISCRETE_INPUTS = 0x02,
+  READ_HOLDING_REGISTERS = 0x03,
+  READ_INPUT_REGISTERS = 0x04,
+  WRITE_SINGLE_COIL = 0x05,
+  WRITE_SINGLE_REGISTER = 0x06,
+  READ_EXCEPTION_STATUS = 0x07,   // not implemented
+  DIAGNOSTICS = 0x08,             // not implemented
+  GET_COMM_EVENT_COUNTER = 0x0B,  // not implemented
+  GET_COMM_EVENT_LOG = 0x0C,      // not implemented
+  WRITE_MULTIPLE_COILS = 0x0F,
+  WRITE_MULTIPLE_REGISTERS = 0x10,
+  REPORT_SERVER_ID = 0x11,               // not implemented
+  READ_FILE_RECORD = 0x14,               // not implemented
+  WRITE_FILE_RECORD = 0x15,              // not implemented
+  MASK_WRITE_REGISTER = 0x16,            // not implemented
+  READ_WRITE_MULTIPLE_REGISTERS = 0x17,  // not implemented
+  READ_FIFO_QUEUE = 0x18,                // not implemented
+};
+
+/*Allow  comparison operators between ModbusFunctionCode and uint8_t*/
+inline bool operator==(ModbusFunctionCode lhs, uint8_t rhs) { return static_cast<uint8_t>(lhs) == rhs; }
+inline bool operator==(uint8_t lhs, ModbusFunctionCode rhs) { return lhs == static_cast<uint8_t>(rhs); }
+inline bool operator!=(ModbusFunctionCode lhs, uint8_t rhs) { return !(static_cast<uint8_t>(lhs) == rhs); }
+inline bool operator!=(uint8_t lhs, ModbusFunctionCode rhs) { return !(lhs == static_cast<uint8_t>(rhs)); }
+inline bool operator<(ModbusFunctionCode lhs, uint8_t rhs) { return static_cast<uint8_t>(lhs) < rhs; }
+inline bool operator<(uint8_t lhs, ModbusFunctionCode rhs) { return lhs < static_cast<uint8_t>(rhs); }
+inline bool operator<=(ModbusFunctionCode lhs, uint8_t rhs) { return static_cast<uint8_t>(lhs) <= rhs; }
+inline bool operator<=(uint8_t lhs, ModbusFunctionCode rhs) { return lhs <= static_cast<uint8_t>(rhs); }
+inline bool operator>(ModbusFunctionCode lhs, uint8_t rhs) { return static_cast<uint8_t>(lhs) > rhs; }
+inline bool operator>(uint8_t lhs, ModbusFunctionCode rhs) { return lhs > static_cast<uint8_t>(rhs); }
+inline bool operator>=(ModbusFunctionCode lhs, uint8_t rhs) { return static_cast<uint8_t>(lhs) >= rhs; }
+inline bool operator>=(uint8_t lhs, ModbusFunctionCode rhs) { return lhs >= static_cast<uint8_t>(rhs); }
+
+// 4.3 MODBUS Data model
+enum class ModbusRegisterType : uint8_t {
+  CUSTOM = 0x00,
+  COIL = 0x01,
+  DISCRETE_INPUT = 0x02,
+  HOLDING = 0x03,
+  READ = 0x04,
+};
+
+// 7 MODBUS Exception Responses:
+const uint8_t FUNCTION_CODE_MASK = 0x7F;
+const uint8_t FUNCTION_CODE_EXCEPTION_MASK = 0x80;
+
+enum class ModbusExceptionCode : uint8_t {
+  ILLEGAL_FUNCTION = 0x01,
+  ILLEGAL_DATA_ADDRESS = 0x02,
+  ILLEGAL_DATA_VALUE = 0x03,
+  SERVICE_DEVICE_FAILURE = 0x04,
+  ACKNOWLEDGE = 0x05,
+  SERVER_DEVICE_BUSY = 0x06,
+  MEMORY_PARITY_ERROR = 0x08,
+  GATEWAY_PATH_UNAVAILABLE = 0x0A,
+  GATEWAY_TARGET_DEVICE_FAILED_TO_RESPOND = 0x0B,
+};
+
+// 6.12 16 (0x10) Write Multiple registers:
+const uint8_t MAX_NUM_OF_REGISTERS_TO_WRITE = 123;  // 0x7B
+
+// 6.3 03 (0x03) Read Holding Registers
+// 6.4 04 (0x04) Read Input Registers
+const uint8_t MAX_NUM_OF_REGISTERS_TO_READ = 125;  // 0x7D
+/// End of Modbus definitions
+}  // namespace modbus
+}  // namespace esphome

esphome/components/modbus_controller/__init__.py

@@ -20,6 +20,7 @@ from .const import (
     CONF_BYTE_OFFSET,
     CONF_COMMAND_THROTTLE,
     CONF_CUSTOM_COMMAND,
+    CONF_ENABLED,
     CONF_FORCE_NEW_RANGE,
     CONF_MAX_CMD_RETRIES,
     CONF_MODBUS_CONTROLLER_ID,
@@ -28,8 +29,11 @@ from .const import (
     CONF_ON_OFFLINE,
     CONF_ON_ONLINE,
     CONF_REGISTER_COUNT,
+    CONF_REGISTER_LAST_ADDRESS,
     CONF_REGISTER_TYPE,
+    CONF_REGISTER_VALUE,
     CONF_RESPONSE_SIZE,
+    CONF_SERVER_COURTESY_RESPONSE,
     CONF_SKIP_UPDATES,
     CONF_VALUE_TYPE,
 )
@@ -49,6 +53,7 @@ ModbusController = modbus_controller_ns.class_(
 )
 
 SensorItem = modbus_controller_ns.struct("SensorItem")
+ServerCourtesyResponse = modbus_controller_ns.struct("ServerCourtesyResponse")
 ServerRegister = modbus_controller_ns.struct("ServerRegister")
 
 ModbusFunctionCode_ns = modbus_controller_ns.namespace("ModbusFunctionCode")
@@ -143,6 +148,14 @@ ModbusOfflineTrigger = modbus_controller_ns.class_(
 
 _LOGGER = logging.getLogger(__name__)
 
+SERVER_COURTESY_RESPONSE_SCHEMA = cv.Schema(
+    {
+        cv.Optional(CONF_ENABLED, default=False): cv.boolean,
+        cv.Optional(CONF_REGISTER_LAST_ADDRESS, default=0xFFFF): cv.hex_uint16_t,
+        cv.Optional(CONF_REGISTER_VALUE, default=0): cv.hex_uint16_t,
+    }
+)
+
 ModbusServerRegisterSchema = cv.Schema(
     {
         cv.GenerateID(): cv.declare_id(ServerRegister),
@@ -162,6 +175,7 @@ CONFIG_SCHEMA = cv.All(
             cv.Optional(
                 CONF_COMMAND_THROTTLE, default="0ms"
             ): cv.positive_time_period_milliseconds,
+            cv.Optional(CONF_SERVER_COURTESY_RESPONSE): SERVER_COURTESY_RESPONSE_SCHEMA,
             cv.Optional(CONF_MAX_CMD_RETRIES, default=4): cv.positive_int,
             cv.Optional(CONF_OFFLINE_SKIP_UPDATES, default=0): cv.positive_int,
             cv.Optional(
@@ -232,7 +246,7 @@ def validate_modbus_register(config):
 
 
 def _final_validate(config):
-    if CONF_SERVER_REGISTERS in config:
+    if CONF_SERVER_COURTESY_RESPONSE in config or CONF_SERVER_REGISTERS in config:
         return modbus.final_validate_modbus_device("modbus_controller", role="server")(
             config
         )
@@ -299,6 +313,20 @@ async def to_code(config):
     var = cg.new_Pvariable(config[CONF_ID])
     cg.add(var.set_allow_duplicate_commands(config[CONF_ALLOW_DUPLICATE_COMMANDS]))
     cg.add(var.set_command_throttle(config[CONF_COMMAND_THROTTLE]))
+    if server_courtesy_response := config.get(CONF_SERVER_COURTESY_RESPONSE):
+        cg.add(
+            var.set_server_courtesy_response(
+                cg.StructInitializer(
+                    ServerCourtesyResponse,
+                    ("enabled", server_courtesy_response[CONF_ENABLED]),
+                    (
+                        "register_last_address",
+                        server_courtesy_response[CONF_REGISTER_LAST_ADDRESS],
+                    ),
+                    ("register_value", server_courtesy_response[CONF_REGISTER_VALUE]),
+                )
+            )
+        )
     cg.add(var.set_max_cmd_retries(config[CONF_MAX_CMD_RETRIES]))
     cg.add(var.set_offline_skip_updates(config[CONF_OFFLINE_SKIP_UPDATES]))
     if CONF_SERVER_REGISTERS in config:

esphome/components/modbus_controller/const.py

@@ -2,6 +2,7 @@ CONF_ALLOW_DUPLICATE_COMMANDS = "allow_duplicate_commands"
 CONF_BITMASK = "bitmask"
 CONF_BYTE_OFFSET = "byte_offset"
 CONF_COMMAND_THROTTLE = "command_throttle"
+CONF_ENABLED = "enabled"
 CONF_OFFLINE_SKIP_UPDATES = "offline_skip_updates"
 CONF_CUSTOM_COMMAND = "custom_command"
 CONF_FORCE_NEW_RANGE = "force_new_range"
@@ -13,8 +14,11 @@ CONF_ON_ONLINE = "on_online"
 CONF_ON_OFFLINE = "on_offline"
 CONF_RAW_ENCODE = "raw_encode"
 CONF_REGISTER_COUNT = "register_count"
+CONF_REGISTER_LAST_ADDRESS = "register_last_address"
 CONF_REGISTER_TYPE = "register_type"
+CONF_REGISTER_VALUE = "register_value"
 CONF_RESPONSE_SIZE = "response_size"
+CONF_SERVER_COURTESY_RESPONSE = "server_courtesy_response"
 CONF_SKIP_UPDATES = "skip_updates"
 CONF_USE_WRITE_MULTIPLE = "use_write_multiple"
 CONF_VALUE_TYPE = "value_type"

esphome/components/modbus_controller/modbus_controller.cpp

@@ -112,6 +112,12 @@ void ModbusController::on_modbus_read_registers(uint8_t function_code, uint16_t
            "0x%X.",
            this->address_, function_code, start_address, number_of_registers);
 
+  if (number_of_registers == 0 || number_of_registers > modbus::MAX_NUM_OF_REGISTERS_TO_READ) {
+    ESP_LOGW(TAG, "Invalid number of registers %d. Sending exception response.", number_of_registers);
+    this->send_error(function_code, ModbusExceptionCode::ILLEGAL_DATA_ADDRESS);
+    return;
+  }
+
   std::vector<uint16_t> sixteen_bit_response;
   for (uint16_t current_address = start_address; current_address < start_address + number_of_registers;) {
     bool found = false;
@@ -136,9 +142,21 @@ void ModbusController::on_modbus_read_registers(uint8_t function_code, uint16_t
     }
 
     if (!found) {
-      ESP_LOGW(TAG, "Could not match any register to address %02X. Sending exception response.", current_address);
-      send_error(function_code, 0x02);
-      return;
+      if (this->server_courtesy_response_.enabled &&
+          (current_address <= this->server_courtesy_response_.register_last_address)) {
+        ESP_LOGD(TAG,
+                 "Could not match any register to address 0x%02X, but default allowed. "
+                 "Returning default value: %d.",
+                 current_address, this->server_courtesy_response_.register_value);
+        sixteen_bit_response.push_back(this->server_courtesy_response_.register_value);
+        current_address += 1;  // Just increment by 1, as the default response is a single register
+      } else {
+        ESP_LOGW(TAG,
+                 "Could not match any register to address 0x%02X and default not allowed. Sending exception response.",
+                 current_address);
+        this->send_error(function_code, ModbusExceptionCode::ILLEGAL_DATA_ADDRESS);
+        return;
+      }
     }
   }
 
@@ -156,27 +174,27 @@ void ModbusController::on_modbus_write_registers(uint8_t function_code, const st
   uint16_t number_of_registers;
   uint16_t payload_offset;
 
-  if (function_code == 0x10) {
+  if (function_code == ModbusFunctionCode::WRITE_MULTIPLE_REGISTERS) {
     number_of_registers = uint16_t(data[3]) | (uint16_t(data[2]) << 8);
-    if (number_of_registers == 0 || number_of_registers > 0x7B) {
+    if (number_of_registers == 0 || number_of_registers > modbus::MAX_NUM_OF_REGISTERS_TO_WRITE) {
       ESP_LOGW(TAG, "Invalid number of registers %d. Sending exception response.", number_of_registers);
-      send_error(function_code, 3);
+      this->send_error(function_code, ModbusExceptionCode::ILLEGAL_DATA_VALUE);
       return;
     }
     uint16_t payload_size = data[4];
     if (payload_size != number_of_registers * 2) {
       ESP_LOGW(TAG, "Payload size of %d bytes is not 2 times the number of registers (%d). Sending exception response.",
                payload_size, number_of_registers);
-      send_error(function_code, 3);
+      this->send_error(function_code, ModbusExceptionCode::ILLEGAL_DATA_VALUE);
       return;
     }
     payload_offset = 5;
-  } else if (function_code == 0x06) {
+  } else if (function_code == ModbusFunctionCode::WRITE_SINGLE_REGISTER) {
     number_of_registers = 1;
     payload_offset = 2;
   } else {
     ESP_LOGW(TAG, "Invalid function code 0x%X. Sending exception response.", function_code);
-    send_error(function_code, 1);
+    this->send_error(function_code, ModbusExceptionCode::ILLEGAL_FUNCTION);
     return;
   }
 
@@ -211,7 +229,7 @@ void ModbusController::on_modbus_write_registers(uint8_t function_code, const st
   if (!for_each_register([](ServerRegister *server_register, uint16_t offset) -> bool {
         return server_register->write_lambda != nullptr;
       })) {
-    send_error(function_code, 1);
+    this->send_error(function_code, ModbusExceptionCode::ILLEGAL_FUNCTION);
     return;
   }
 
@@ -220,7 +238,7 @@ void ModbusController::on_modbus_write_registers(uint8_t function_code, const st
         int64_t number = payload_to_number(data, server_register->value_type, offset, 0xFFFFFFFF);
         return server_register->write_lambda(number);
       })) {
-    send_error(function_code, 4);
+    this->send_error(function_code, ModbusExceptionCode::SERVICE_DEVICE_FAILURE);
     return;
   }
 
@@ -431,8 +449,15 @@ void ModbusController::dump_config() {
                 "ModbusController:\n"
                 "  Address: 0x%02X\n"
                 "  Max Command Retries: %d\n"
-                "  Offline Skip Updates: %d",
-                this->address_, this->max_cmd_retries_, this->offline_skip_updates_);
+                "  Offline Skip Updates: %d\n"
+                "  Server Courtesy Response:\n"
+                "    Enabled: %s\n"
+                "    Register Last Address: 0x%02X\n"
+                "    Register Value: %d",
+                this->address_, this->max_cmd_retries_, this->offline_skip_updates_,
+                this->server_courtesy_response_.enabled ? "true" : "false",
+                this->server_courtesy_response_.register_last_address, this->server_courtesy_response_.register_value);
+
 #if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
   ESP_LOGCONFIG(TAG, "sensormap");
   for (auto &it : this->sensorset_) {

esphome/components/modbus_controller/modbus_controller.h

@@ -16,35 +16,9 @@ namespace modbus_controller {
 
 class ModbusController;
 
-enum class ModbusFunctionCode {
-  CUSTOM = 0x00,
-  READ_COILS = 0x01,
-  READ_DISCRETE_INPUTS = 0x02,
-  READ_HOLDING_REGISTERS = 0x03,
-  READ_INPUT_REGISTERS = 0x04,
-  WRITE_SINGLE_COIL = 0x05,
-  WRITE_SINGLE_REGISTER = 0x06,
-  READ_EXCEPTION_STATUS = 0x07,   // not implemented
-  DIAGNOSTICS = 0x08,             // not implemented
-  GET_COMM_EVENT_COUNTER = 0x0B,  // not implemented
-  GET_COMM_EVENT_LOG = 0x0C,      // not implemented
-  WRITE_MULTIPLE_COILS = 0x0F,
-  WRITE_MULTIPLE_REGISTERS = 0x10,
-  REPORT_SERVER_ID = 0x11,               // not implemented
-  READ_FILE_RECORD = 0x14,               // not implemented
-  WRITE_FILE_RECORD = 0x15,              // not implemented
-  MASK_WRITE_REGISTER = 0x16,            // not implemented
-  READ_WRITE_MULTIPLE_REGISTERS = 0x17,  // not implemented
-  READ_FIFO_QUEUE = 0x18,                // not implemented
-};
-
-enum class ModbusRegisterType : uint8_t {
-  CUSTOM = 0x0,
-  COIL = 0x01,
-  DISCRETE_INPUT = 0x02,
-  HOLDING = 0x03,
-  READ = 0x04,
-};
+using modbus::ModbusFunctionCode;
+using modbus::ModbusRegisterType;
+using modbus::ModbusExceptionCode;
 
 enum class SensorValueType : uint8_t {
   RAW = 0x00,     // variable length
@@ -256,6 +230,12 @@ class SensorItem {
   bool force_new_range{false};
 };
 
+struct ServerCourtesyResponse {
+  bool enabled{false};
+  uint16_t register_last_address{0xFFFF};
+  uint16_t register_value{0};
+};
+
 class ServerRegister {
   using ReadLambda = std::function<int64_t()>;
   using WriteLambda = std::function<bool(int64_t value)>;
@@ -530,6 +510,12 @@ class ModbusController : public PollingComponent, public modbus::ModbusDevice {
   void set_max_cmd_retries(uint8_t max_cmd_retries) { this->max_cmd_retries_ = max_cmd_retries; }
   /// get how many times a command will be (re)sent if no response is received
   uint8_t get_max_cmd_retries() { return this->max_cmd_retries_; }
+  /// Called by esphome generated code to set the server courtesy response object
+  void set_server_courtesy_response(const ServerCourtesyResponse &server_courtesy_response) {
+    this->server_courtesy_response_ = server_courtesy_response;
+  }
+  /// Get the server courtesy response object
+  ServerCourtesyResponse get_server_courtesy_response() const { return this->server_courtesy_response_; }
 
  protected:
   /// parse sensormap_ and create range of sequential addresses
@@ -572,6 +558,9 @@ class ModbusController : public PollingComponent, public modbus::ModbusDevice {
   CallbackManager<void(int, int)> online_callback_{};
   /// Server offline callback
   CallbackManager<void(int, int)> offline_callback_{};
+  /// Server courtesy response
+  ServerCourtesyResponse server_courtesy_response_{
+      .enabled = false, .register_last_address = 0xFFFF, .register_value = 0};
 };
 
 /** Convert vector<uint8_t> response payload to float.

esphome/components/mqtt/mqtt_client.cpp

@@ -29,7 +29,8 @@ static const char *const TAG = "mqtt";
 
 MQTTClientComponent::MQTTClientComponent() {
   global_mqtt_client = this;
-  this->credentials_.client_id = App.get_name() + "-" + get_mac_address();
+  const std::string mac_addr = get_mac_address();
+  this->credentials_.client_id = make_name_with_suffix(App.get_name(), '-', mac_addr.c_str(), mac_addr.size());
 }
 
 // Connection

esphome/components/opentherm/opentherm.cpp

@@ -7,7 +7,7 @@
 
 #include "opentherm.h"
 #include "esphome/core/helpers.h"
-#if defined(ESP32) || defined(USE_ESP_IDF)
+#ifdef USE_ESP32
 #include "driver/timer.h"
 #include "esp_err.h"
 #endif
@@ -31,7 +31,7 @@ OpenTherm *OpenTherm::instance = nullptr;
 OpenTherm::OpenTherm(InternalGPIOPin *in_pin, InternalGPIOPin *out_pin, int32_t device_timeout)
     : in_pin_(in_pin),
       out_pin_(out_pin),
-#if defined(ESP32) || defined(USE_ESP_IDF)
+#ifdef USE_ESP32
       timer_group_(TIMER_GROUP_0),
       timer_idx_(TIMER_0),
 #endif
@@ -57,7 +57,7 @@ bool OpenTherm::initialize() {
   this->out_pin_->setup();
   this->out_pin_->digital_write(true);
 
-#if defined(ESP32) || defined(USE_ESP_IDF)
+#ifdef USE_ESP32
   return this->init_esp32_timer_();
 #else
   return true;
@@ -238,7 +238,7 @@ void IRAM_ATTR OpenTherm::write_bit_(uint8_t high, uint8_t clock) {
   }
 }
 
-#if defined(ESP32) || defined(USE_ESP_IDF)
+#ifdef USE_ESP32
 
 bool OpenTherm::init_esp32_timer_() {
   // Search for a free timer. Maybe unstable, we'll see.
@@ -365,7 +365,7 @@ void IRAM_ATTR OpenTherm::stop_timer_() {
   }
 }
 
-#endif  // END ESP32
+#endif  // USE_ESP32
 
 #ifdef ESP8266
 // 5 kHz timer_

esphome/components/opentherm/opentherm.h

@@ -12,7 +12,7 @@
 #include "esphome/core/helpers.h"
 #include "esphome/core/log.h"
 
-#if defined(ESP32) || defined(USE_ESP_IDF)
+#ifdef USE_ESP32
 #include "driver/timer.h"
 #endif
 
@@ -356,7 +356,7 @@ class OpenTherm {
   ISRInternalGPIOPin isr_in_pin_;
   ISRInternalGPIOPin isr_out_pin_;
 
-#if defined(ESP32) || defined(USE_ESP_IDF)
+#ifdef USE_ESP32
   timer_group_t timer_group_;
   timer_idx_t timer_idx_;
 #endif
@@ -370,7 +370,7 @@ class OpenTherm {
   int32_t timeout_counter_;  // <0 no timeout
   int32_t device_timeout_;
 
-#if defined(ESP32) || defined(USE_ESP_IDF)
+#ifdef USE_ESP32
   esp_err_t timer_error_ = ESP_OK;
   TimerErrorType timer_error_type_ = TimerErrorType::NO_TIMER_ERROR;
 

esphome/components/openthread/__init__.py

@@ -5,7 +5,7 @@ from esphome.components.esp32 import (
     add_idf_sdkconfig_option,
     only_on_variant,
 )
-from esphome.components.mdns import MDNSComponent
+from esphome.components.mdns import MDNSComponent, enable_mdns_storage
 import esphome.config_validation as cv
 from esphome.const import CONF_CHANNEL, CONF_ENABLE_IPV6, CONF_ID
 import esphome.final_validate as fv
@@ -141,6 +141,9 @@ FINAL_VALIDATE_SCHEMA = _final_validate
 async def to_code(config):
     cg.add_define("USE_OPENTHREAD")
 
+    # OpenThread SRP needs access to mDNS services after setup
+    enable_mdns_storage()
+
     ot = cg.new_Pvariable(config[CONF_ID])
     await cg.register_component(ot, config)
 

esphome/components/openthread/openthread.cpp

@@ -155,7 +155,7 @@ void OpenThreadSrpComponent::setup() {
 
     // Set service name
     char *string = otSrpClientBuffersGetServiceEntryServiceNameString(entry, &size);
-    std::string full_service = service.service_type + "." + service.proto;
+    std::string full_service = std::string(MDNS_STR_ARG(service.service_type)) + "." + MDNS_STR_ARG(service.proto);
     if (full_service.size() > size) {
       ESP_LOGW(TAG, "Service name too long: %s", full_service.c_str());
       continue;
@@ -180,10 +180,12 @@ void OpenThreadSrpComponent::setup() {
     entry->mService.mNumTxtEntries = service.txt_records.size();
     for (size_t i = 0; i < service.txt_records.size(); i++) {
       const auto &txt = service.txt_records[i];
-      auto value = const_cast<TemplatableValue<std::string> &>(txt.value).value();
-      txt_entries[i].mKey = strdup(txt.key.c_str());
-      txt_entries[i].mValue = reinterpret_cast<const uint8_t *>(strdup(value.c_str()));
-      txt_entries[i].mValueLength = value.size();
+      // Value is either a compile-time string literal in flash or a pointer to dynamic_txt_values_
+      // OpenThread SRP client expects the data to persist, so we strdup it
+      const char *value_str = MDNS_STR_ARG(txt.value);
+      txt_entries[i].mKey = MDNS_STR_ARG(txt.key);
+      txt_entries[i].mValue = reinterpret_cast<const uint8_t *>(strdup(value_str));
+      txt_entries[i].mValueLength = strlen(value_str);
     }
     entry->mService.mTxtEntries = txt_entries;
     entry->mService.mNumTxtEntries = service.txt_records.size();

esphome/components/socket/lwip_raw_tcp_impl.cpp

@@ -40,33 +40,14 @@ class LWIPRawImpl : public Socket {
   void init() {
     LWIP_LOG("init(%p)", pcb_);
     tcp_arg(pcb_, this);
-    tcp_accept(pcb_, LWIPRawImpl::s_accept_fn);
     tcp_recv(pcb_, LWIPRawImpl::s_recv_fn);
     tcp_err(pcb_, LWIPRawImpl::s_err_fn);
   }
 
   std::unique_ptr<Socket> accept(struct sockaddr *addr, socklen_t *addrlen) override {
-    if (pcb_ == nullptr) {
-      errno = EBADF;
-      return nullptr;
-    }
-    if (this->accepted_socket_count_ == 0) {
-      errno = EWOULDBLOCK;
-      return nullptr;
-    }
-    // Take from front for FIFO ordering
-    std::unique_ptr<LWIPRawImpl> sock = std::move(this->accepted_sockets_[0]);
-    // Shift remaining sockets forward
-    for (uint8_t i = 1; i < this->accepted_socket_count_; i++) {
-      this->accepted_sockets_[i - 1] = std::move(this->accepted_sockets_[i]);
-    }
-    this->accepted_socket_count_--;
-    LWIP_LOG("Connection accepted by application, queue size: %d", this->accepted_socket_count_);
-    if (addr != nullptr) {
-      sock->getpeername(addr, addrlen);
-    }
-    LWIP_LOG("accept(%p)", sock.get());
-    return std::unique_ptr<Socket>(std::move(sock));
+    // Non-listening sockets return error
+    errno = EINVAL;
+    return nullptr;
   }
   int bind(const struct sockaddr *name, socklen_t addrlen) override {
     if (pcb_ == nullptr) {
@@ -292,25 +273,10 @@ class LWIPRawImpl : public Socket {
     return -1;
   }
   int listen(int backlog) override {
-    if (pcb_ == nullptr) {
-      errno = EBADF;
-      return -1;
-    }
-    LWIP_LOG("tcp_listen_with_backlog(%p backlog=%d)", pcb_, backlog);
-    struct tcp_pcb *listen_pcb = tcp_listen_with_backlog(pcb_, backlog);
-    if (listen_pcb == nullptr) {
-      tcp_abort(pcb_);
-      pcb_ = nullptr;
-      errno = EOPNOTSUPP;
-      return -1;
-    }
-    // tcp_listen reallocates the pcb, replace ours
-    pcb_ = listen_pcb;
-    // set callbacks on new pcb
-    LWIP_LOG("tcp_arg(%p)", pcb_);
-    tcp_arg(pcb_, this);
-    tcp_accept(pcb_, LWIPRawImpl::s_accept_fn);
-    return 0;
+    // Regular sockets can't be converted to listening - this shouldn't happen
+    // as listen() should only be called on sockets created for listening
+    errno = EOPNOTSUPP;
+    return -1;
   }
   ssize_t read(void *buf, size_t len) override {
     if (pcb_ == nullptr) {
@@ -491,29 +457,6 @@ class LWIPRawImpl : public Socket {
     return 0;
   }
 
-  err_t accept_fn(struct tcp_pcb *newpcb, err_t err) {
-    LWIP_LOG("accept(newpcb=%p err=%d)", newpcb, err);
-    if (err != ERR_OK || newpcb == nullptr) {
-      // "An error code if there has been an error accepting. Only return ERR_ABRT if you have
-      // called tcp_abort from within the callback function!"
-      // https://www.nongnu.org/lwip/2_1_x/tcp_8h.html#a00517abce6856d6c82f0efebdafb734d
-      // nothing to do here, we just don't push it to the queue
-      return ERR_OK;
-    }
-    // Check if we've reached the maximum accept queue size
-    if (this->accepted_socket_count_ >= MAX_ACCEPTED_SOCKETS) {
-      LWIP_LOG("Rejecting connection, queue full (%d)", this->accepted_socket_count_);
-      // Abort the connection when queue is full
-      tcp_abort(newpcb);
-      // Must return ERR_ABRT since we called tcp_abort()
-      return ERR_ABRT;
-    }
-    auto sock = make_unique<LWIPRawImpl>(family_, newpcb);
-    sock->init();
-    this->accepted_sockets_[this->accepted_socket_count_++] = std::move(sock);
-    LWIP_LOG("Accepted connection, queue size: %d", this->accepted_socket_count_);
-    return ERR_OK;
-  }
   void err_fn(err_t err) {
     LWIP_LOG("err(err=%d)", err);
     // "If a connection is aborted because of an error, the application is alerted of this event by
@@ -545,11 +488,6 @@ class LWIPRawImpl : public Socket {
     return ERR_OK;
   }
 
-  static err_t s_accept_fn(void *arg, struct tcp_pcb *newpcb, err_t err) {
-    LWIPRawImpl *arg_this = reinterpret_cast<LWIPRawImpl *>(arg);
-    return arg_this->accept_fn(newpcb, err);
-  }
-
   static void s_err_fn(void *arg, err_t err) {
     LWIPRawImpl *arg_this = reinterpret_cast<LWIPRawImpl *>(arg);
     arg_this->err_fn(err);
@@ -601,7 +539,107 @@ class LWIPRawImpl : public Socket {
     return -1;
   }
 
+  // Member ordering optimized to minimize padding on 32-bit systems
+  // Largest members first (4 bytes), then smaller members (1 byte each)
   struct tcp_pcb *pcb_;
+  pbuf *rx_buf_ = nullptr;
+  size_t rx_buf_offset_ = 0;
+  bool rx_closed_ = false;
+  // don't use lwip nodelay flag, it sometimes causes reconnect
+  // instead use it for determining whether to call lwip_output
+  bool nodelay_ = false;
+  sa_family_t family_ = 0;
+};
+
+// Listening socket class - only allocates accept queue when needed (for bind+listen sockets)
+// This saves 16 bytes (12 bytes array + 1 byte count + 3 bytes padding) for regular connected sockets on ESP8266/RP2040
+class LWIPRawListenImpl : public LWIPRawImpl {
+ public:
+  LWIPRawListenImpl(sa_family_t family, struct tcp_pcb *pcb) : LWIPRawImpl(family, pcb) {}
+
+  void init() {
+    LWIP_LOG("init(%p)", pcb_);
+    tcp_arg(pcb_, this);
+    tcp_accept(pcb_, LWIPRawListenImpl::s_accept_fn);
+    tcp_err(pcb_, LWIPRawImpl::s_err_fn);  // Use base class error handler
+  }
+
+  std::unique_ptr<Socket> accept(struct sockaddr *addr, socklen_t *addrlen) override {
+    if (pcb_ == nullptr) {
+      errno = EBADF;
+      return nullptr;
+    }
+    if (accepted_socket_count_ == 0) {
+      errno = EWOULDBLOCK;
+      return nullptr;
+    }
+    // Take from front for FIFO ordering
+    std::unique_ptr<LWIPRawImpl> sock = std::move(accepted_sockets_[0]);
+    // Shift remaining sockets forward
+    for (uint8_t i = 1; i < accepted_socket_count_; i++) {
+      accepted_sockets_[i - 1] = std::move(accepted_sockets_[i]);
+    }
+    accepted_socket_count_--;
+    LWIP_LOG("Connection accepted by application, queue size: %d", accepted_socket_count_);
+    if (addr != nullptr) {
+      sock->getpeername(addr, addrlen);
+    }
+    LWIP_LOG("accept(%p)", sock.get());
+    return std::unique_ptr<Socket>(std::move(sock));
+  }
+
+  int listen(int backlog) override {
+    if (pcb_ == nullptr) {
+      errno = EBADF;
+      return -1;
+    }
+    LWIP_LOG("tcp_listen_with_backlog(%p backlog=%d)", pcb_, backlog);
+    struct tcp_pcb *listen_pcb = tcp_listen_with_backlog(pcb_, backlog);
+    if (listen_pcb == nullptr) {
+      tcp_abort(pcb_);
+      pcb_ = nullptr;
+      errno = EOPNOTSUPP;
+      return -1;
+    }
+    // tcp_listen reallocates the pcb, replace ours
+    pcb_ = listen_pcb;
+    // set callbacks on new pcb
+    LWIP_LOG("tcp_arg(%p)", pcb_);
+    tcp_arg(pcb_, this);
+    tcp_accept(pcb_, LWIPRawListenImpl::s_accept_fn);
+    return 0;
+  }
+
+ private:
+  err_t accept_fn(struct tcp_pcb *newpcb, err_t err) {
+    LWIP_LOG("accept(newpcb=%p err=%d)", newpcb, err);
+    if (err != ERR_OK || newpcb == nullptr) {
+      // "An error code if there has been an error accepting. Only return ERR_ABRT if you have
+      // called tcp_abort from within the callback function!"
+      // https://www.nongnu.org/lwip/2_1_x/tcp_8h.html#a00517abce6856d6c82f0efebdafb734d
+      // nothing to do here, we just don't push it to the queue
+      return ERR_OK;
+    }
+    // Check if we've reached the maximum accept queue size
+    if (accepted_socket_count_ >= MAX_ACCEPTED_SOCKETS) {
+      LWIP_LOG("Rejecting connection, queue full (%d)", accepted_socket_count_);
+      // Abort the connection when queue is full
+      tcp_abort(newpcb);
+      // Must return ERR_ABRT since we called tcp_abort()
+      return ERR_ABRT;
+    }
+    auto sock = make_unique<LWIPRawImpl>(family_, newpcb);
+    sock->init();
+    accepted_sockets_[accepted_socket_count_++] = std::move(sock);
+    LWIP_LOG("Accepted connection, queue size: %d", accepted_socket_count_);
+    return ERR_OK;
+  }
+
+  static err_t s_accept_fn(void *arg, struct tcp_pcb *newpcb, err_t err) {
+    LWIPRawListenImpl *arg_this = reinterpret_cast<LWIPRawListenImpl *>(arg);
+    return arg_this->accept_fn(newpcb, err);
+  }
+
   // Accept queue - holds incoming connections briefly until the event loop calls accept()
   // This is NOT a connection pool - just a temporary queue between LWIP callbacks and the main loop
   // 3 slots is plenty since connections are pulled out quickly by the event loop
@@ -613,23 +651,21 @@ class LWIPRawImpl : public Socket {
   // - std::array<3>: 12 bytes fixed (3 pointers × 4 bytes)
   // Saves ~44+ bytes RAM per listening socket + avoids ALL heap allocations
   // Used on ESP8266 and RP2040 (platforms using LWIP_TCP implementation)
+  //
+  // By using a separate listening socket class, regular connected sockets save
+  // 16 bytes (12 bytes array + 1 byte count + 3 bytes padding) of memory overhead on 32-bit systems
   static constexpr size_t MAX_ACCEPTED_SOCKETS = 3;
   std::array<std::unique_ptr<LWIPRawImpl>, MAX_ACCEPTED_SOCKETS> accepted_sockets_;
   uint8_t accepted_socket_count_ = 0;  // Number of sockets currently in queue
-  bool rx_closed_ = false;
-  pbuf *rx_buf_ = nullptr;
-  size_t rx_buf_offset_ = 0;
-  // don't use lwip nodelay flag, it sometimes causes reconnect
-  // instead use it for determining whether to call lwip_output
-  bool nodelay_ = false;
-  sa_family_t family_ = 0;
 };
 
 std::unique_ptr<Socket> socket(int domain, int type, int protocol) {
   auto *pcb = tcp_new();
   if (pcb == nullptr)
     return nullptr;
-  auto *sock = new LWIPRawImpl((sa_family_t) domain, pcb);  // NOLINT(cppcoreguidelines-owning-memory)
+  // Create listening socket implementation since user sockets typically bind+listen
+  // Accepted connections are created directly as LWIPRawImpl in the accept callback
+  auto *sock = new LWIPRawListenImpl((sa_family_t) domain, pcb);  // NOLINT(cppcoreguidelines-owning-memory)
   sock->init();
   return std::unique_ptr<Socket>{sock};
 }

esphome/components/split_buffer/__init__.py

@@ -0,0 +1,5 @@
+CODEOWNERS = ["@jesserockz"]
+
+# Allows split_buffer to be configured in yaml, to allow use of the C++ api.
+
+CONFIG_SCHEMA = {}

esphome/components/split_buffer/split_buffer.cpp

@@ -0,0 +1,133 @@
+#include "split_buffer.h"
+
+#include "esphome/core/helpers.h"
+#include "esphome/core/log.h"
+
+namespace esphome::split_buffer {
+
+static constexpr const char *const TAG = "split_buffer";
+
+SplitBuffer::~SplitBuffer() { this->free(); }
+
+bool SplitBuffer::init(size_t total_length) {
+  this->free();  // Clean up any existing allocation
+
+  if (total_length == 0) {
+    return false;
+  }
+
+  this->total_length_ = total_length;
+  size_t current_buffer_size = total_length;
+
+  RAMAllocator<uint8_t *> ptr_allocator;
+  RAMAllocator<uint8_t> allocator;
+
+  // Try to allocate the entire buffer first
+  while (current_buffer_size > 0) {
+    // Calculate how many buffers we need of this size
+    size_t needed_buffers = (total_length + current_buffer_size - 1) / current_buffer_size;
+
+    // Try to allocate array of buffer pointers
+    uint8_t **temp_buffers = ptr_allocator.allocate(needed_buffers);
+    if (temp_buffers == nullptr) {
+      // If we can't even allocate the pointer array, don't need to continue
+      ESP_LOGE(TAG, "Failed to allocate pointers");
+      return false;
+    }
+
+    // Initialize all pointers to null
+    for (size_t i = 0; i < needed_buffers; i++) {
+      temp_buffers[i] = nullptr;
+    }
+
+    // Try to allocate all the buffers
+    bool allocation_success = true;
+    for (size_t i = 0; i < needed_buffers; i++) {
+      size_t this_buffer_size = current_buffer_size;
+      // Last buffer might be smaller if total_length is not divisible by current_buffer_size
+      if (i == needed_buffers - 1 && total_length % current_buffer_size != 0) {
+        this_buffer_size = total_length % current_buffer_size;
+      }
+
+      temp_buffers[i] = allocator.allocate(this_buffer_size);
+      if (temp_buffers[i] == nullptr) {
+        allocation_success = false;
+        break;
+      }
+
+      // Initialize buffer to zero
+      memset(temp_buffers[i], 0, this_buffer_size);
+    }
+
+    if (allocation_success) {
+      // Success! Store the result
+      this->buffers_ = temp_buffers;
+      this->buffer_count_ = needed_buffers;
+      this->buffer_size_ = current_buffer_size;
+      ESP_LOGD(TAG, "Allocated %zu * %zu bytes - %zu bytes", this->buffer_count_, this->buffer_size_,
+               this->total_length_);
+      return true;
+    }
+
+    // Allocation failed, clean up and try smaller buffers
+    for (size_t i = 0; i < needed_buffers; i++) {
+      if (temp_buffers[i] != nullptr) {
+        allocator.deallocate(temp_buffers[i], 0);
+      }
+    }
+    ptr_allocator.deallocate(temp_buffers, 0);
+
+    // Halve the buffer size and try again
+    current_buffer_size = current_buffer_size / 2;
+  }
+
+  ESP_LOGE(TAG, "Failed to allocate %zu bytes", total_length);
+  return false;
+}
+
+void SplitBuffer::free() {
+  if (this->buffers_ != nullptr) {
+    RAMAllocator<uint8_t> allocator;
+    for (size_t i = 0; i < this->buffer_count_; i++) {
+      if (this->buffers_[i] != nullptr) {
+        allocator.deallocate(this->buffers_[i], 0);
+      }
+    }
+    RAMAllocator<uint8_t *> ptr_allocator;
+    ptr_allocator.deallocate(this->buffers_, 0);
+    this->buffers_ = nullptr;
+  }
+  this->buffer_count_ = 0;
+  this->buffer_size_ = 0;
+  this->total_length_ = 0;
+}
+
+uint8_t &SplitBuffer::operator[](size_t index) {
+  if (index >= this->total_length_) {
+    ESP_LOGE(TAG, "Out of bounds - %zu >= %zu", index, this->total_length_);
+    // Return reference to a static dummy byte to avoid crash
+    static uint8_t dummy = 0;
+    return dummy;
+  }
+
+  size_t buffer_index = index / this->buffer_size_;
+  size_t offset_in_buffer = index - this->buffer_size_ * buffer_index;
+
+  return this->buffers_[buffer_index][offset_in_buffer];
+}
+
+const uint8_t &SplitBuffer::operator[](size_t index) const {
+  if (index >= this->total_length_) {
+    ESP_LOGE(TAG, "Out of bounds - %zu >= %zu", index, this->total_length_);
+    // Return reference to a static dummy byte to avoid crash
+    static const uint8_t DUMMY = 0;
+    return DUMMY;
+  }
+
+  size_t buffer_index = index / this->buffer_size_;
+  size_t offset_in_buffer = index - this->buffer_size_ * buffer_index;
+
+  return this->buffers_[buffer_index][offset_in_buffer];
+}
+
+}  // namespace esphome::split_buffer

esphome/components/split_buffer/split_buffer.h

@@ -0,0 +1,40 @@
+#pragma once
+
+#include <cstdint>
+#include <cstdlib>
+
+namespace esphome::split_buffer {
+
+class SplitBuffer {
+ public:
+  SplitBuffer() = default;
+  ~SplitBuffer();
+
+  // Initialize the buffer with the desired total length
+  bool init(size_t total_length);
+
+  // Free all allocated buffers
+  void free();
+
+  // Access operators
+  uint8_t &operator[](size_t index);
+  const uint8_t &operator[](size_t index) const;
+
+  // Get the total length
+  size_t size() const { return this->total_length_; }
+
+  // Get buffer information
+  size_t get_buffer_count() const { return this->buffer_count_; }
+  size_t get_buffer_size() const { return this->buffer_size_; }
+
+  // Check if successfully initialized
+  bool is_valid() const { return this->buffers_ != nullptr && this->buffer_count_ > 0; }
+
+ private:
+  uint8_t **buffers_{nullptr};
+  size_t buffer_count_{0};
+  size_t buffer_size_{0};
+  size_t total_length_{0};
+};
+
+}  // namespace esphome::split_buffer

esphome/components/uart/__init__.py

@@ -347,7 +347,7 @@ def final_validate_device_schema(
 
     def validate_pin(opt, device):
         def validator(value):
-            if opt in device:
+            if opt in device and not CORE.testing_mode:
                 raise cv.Invalid(
                     f"The uart {opt} is used both by {name} and {device[opt]}, "
                     f"but can only be used by one. Please create a new uart bus for {name}."

esphome/components/usb_host/__init__.py

@@ -9,6 +9,7 @@ from esphome.components.esp32 import (
 import esphome.config_validation as cv
 from esphome.const import CONF_DEVICES, CONF_ID
 from esphome.cpp_types import Component
+from esphome.types import ConfigType
 
 AUTO_LOAD = ["bytebuffer"]
 CODEOWNERS = ["@clydebarrow"]
@@ -20,6 +21,7 @@ USBClient = usb_host_ns.class_("USBClient", Component)
 CONF_VID = "vid"
 CONF_PID = "pid"
 CONF_ENABLE_HUBS = "enable_hubs"
+CONF_MAX_TRANSFER_REQUESTS = "max_transfer_requests"
 
 
 def usb_device_schema(cls=USBClient, vid: int = None, pid: [int] = None) -> cv.Schema:
@@ -44,6 +46,9 @@ CONFIG_SCHEMA = cv.All(
         {
             cv.GenerateID(): cv.declare_id(USBHost),
             cv.Optional(CONF_ENABLE_HUBS, default=False): cv.boolean,
+            cv.Optional(CONF_MAX_TRANSFER_REQUESTS, default=16): cv.int_range(
+                min=1, max=32
+            ),
             cv.Optional(CONF_DEVICES): cv.ensure_list(usb_device_schema()),
         }
     ),
@@ -58,10 +63,14 @@ async def register_usb_client(config):
     return var
 
 
-async def to_code(config):
+async def to_code(config: ConfigType) -> None:
     add_idf_sdkconfig_option("CONFIG_USB_HOST_CONTROL_TRANSFER_MAX_SIZE", 1024)
     if config.get(CONF_ENABLE_HUBS):
         add_idf_sdkconfig_option("CONFIG_USB_HOST_HUBS_SUPPORTED", True)
+
+    max_requests = config[CONF_MAX_TRANSFER_REQUESTS]
+    cg.add_define("USB_HOST_MAX_REQUESTS", max_requests)
+
     var = cg.new_Pvariable(config[CONF_ID])
     await cg.register_component(var, config)
     for device in config.get(CONF_DEVICES) or ():

esphome/components/usb_host/usb_host.h

@@ -2,6 +2,7 @@
 
 // Should not be needed, but it's required to pass CI clang-tidy checks
 #if defined(USE_ESP32_VARIANT_ESP32S2) || defined(USE_ESP32_VARIANT_ESP32S3) || defined(USE_ESP32_VARIANT_ESP32P4)
+#include "esphome/core/defines.h"
 #include "esphome/core/component.h"
 #include <vector>
 #include "usb/usb_host.h"
@@ -16,23 +17,25 @@ namespace usb_host {
 
 // THREADING MODEL:
 // This component uses a dedicated USB task for event processing to prevent data loss.
-// - USB Task (high priority): Handles USB events, executes transfer callbacks
-// - Main Loop Task: Initiates transfers, processes completion events
+// - USB Task (high priority): Handles USB events, executes transfer callbacks, releases transfer slots
+// - Main Loop Task: Initiates transfers, processes device connect/disconnect events
 //
 // Thread-safe communication:
 // - Lock-free queues for USB task -> main loop events (SPSC pattern)
-// - Lock-free TransferRequest pool using atomic bitmask (MCSP pattern)
+// - Lock-free TransferRequest pool using atomic bitmask (MCMP pattern - multi-consumer, multi-producer)
 //
 // TransferRequest pool access pattern:
 // - get_trq_() [allocate]: Called from BOTH USB task and main loop threads
 //   * USB task: via USB UART input callbacks that restart transfers immediately
 //   * Main loop: for output transfers and flow-controlled input restarts
-// - release_trq() [deallocate]: Called from main loop thread only
+// - release_trq() [deallocate]: Called from BOTH USB task and main loop threads
+//   * USB task: immediately after transfer callback completes (critical for preventing slot exhaustion)
+//   * Main loop: when transfer submission fails
 //
-// The multi-threaded allocation is intentional for performance:
-// - USB task can immediately restart input transfers without context switching
+// The multi-threaded allocation/deallocation is intentional for performance:
+// - USB task can immediately restart input transfers and release slots without context switching
 // - Main loop controls backpressure by deciding when to restart after consuming data
-// The atomic bitmask ensures thread-safe allocation without mutex blocking.
+// The atomic bitmask ensures thread-safe allocation/deallocation without mutex blocking.
 
 static const char *const TAG = "usb_host";
 
@@ -52,8 +55,13 @@ static const uint8_t USB_DIR_IN = 1 << 7;
 static const uint8_t USB_DIR_OUT = 0;
 static const size_t SETUP_PACKET_SIZE = 8;
 
-static const size_t MAX_REQUESTS = 16;  // maximum number of outstanding requests possible.
-static_assert(MAX_REQUESTS <= 16, "MAX_REQUESTS must be <= 16 to fit in uint16_t bitmask");
+static const size_t MAX_REQUESTS = USB_HOST_MAX_REQUESTS;  // maximum number of outstanding requests possible.
+static_assert(MAX_REQUESTS >= 1 && MAX_REQUESTS <= 32, "MAX_REQUESTS must be between 1 and 32");
+
+// Select appropriate bitmask type based on MAX_REQUESTS
+// uint16_t for <= 16 requests, uint32_t for 17-32 requests
+using trq_bitmask_t = std::conditional<(MAX_REQUESTS <= 16), uint16_t, uint32_t>::type;
+
 static constexpr size_t USB_EVENT_QUEUE_SIZE = 32;   // Size of event queue between USB task and main loop
 static constexpr size_t USB_TASK_STACK_SIZE = 4096;  // Stack size for USB task (same as ESP-IDF USB examples)
 static constexpr UBaseType_t USB_TASK_PRIORITY = 5;  // Higher priority than main loop (tskIDLE_PRIORITY + 5)
@@ -83,8 +91,6 @@ struct TransferRequest {
 enum EventType : uint8_t {
   EVENT_DEVICE_NEW,
   EVENT_DEVICE_GONE,
-  EVENT_TRANSFER_COMPLETE,
-  EVENT_CONTROL_COMPLETE,
 };
 
 struct UsbEvent {
@@ -96,9 +102,6 @@ struct UsbEvent {
     struct {
       usb_device_handle_t handle;
     } device_gone;
-    struct {
-      TransferRequest *trq;
-    } transfer;
   } data;
 
   // Required for EventPool - no cleanup needed for POD types
@@ -163,10 +166,9 @@ class USBClient : public Component {
   uint16_t pid_{};
   // Lock-free pool management using atomic bitmask (no dynamic allocation)
   // Bit i = 1: requests_[i] is in use, Bit i = 0: requests_[i] is available
-  // Supports multiple concurrent consumers (both threads can allocate)
-  // Single producer for deallocation (main loop only)
-  // Limited to 16 slots by uint16_t size (enforced by static_assert)
-  std::atomic<uint16_t> trq_in_use_;
+  // Supports multiple concurrent consumers and producers (both threads can allocate/deallocate)
+  // Bitmask type automatically selected: uint16_t for <= 16 slots, uint32_t for 17-32 slots
+  std::atomic<trq_bitmask_t> trq_in_use_;
   TransferRequest requests_[MAX_REQUESTS]{};
 };
 class USBHost : public Component {

esphome/components/usb_host/usb_host_client.cpp

@@ -228,12 +228,6 @@ void USBClient::loop() {
       case EVENT_DEVICE_GONE:
         this->on_removed(event->data.device_gone.handle);
         break;
-      case EVENT_TRANSFER_COMPLETE:
-      case EVENT_CONTROL_COMPLETE: {
-        auto *trq = event->data.transfer.trq;
-        this->release_trq(trq);
-        break;
-      }
     }
     // Return event to pool for reuse
     this->event_pool.release(event);
@@ -313,25 +307,6 @@ void USBClient::on_removed(usb_device_handle_t handle) {
   }
 }
 
-// Helper to queue transfer cleanup to main loop
-static void queue_transfer_cleanup(TransferRequest *trq, EventType type) {
-  auto *client = trq->client;
-
-  // Allocate event from pool
-  UsbEvent *event = client->event_pool.allocate();
-  if (event == nullptr) {
-    // No events available - increment counter for periodic logging
-    client->event_queue.increment_dropped_count();
-    return;
-  }
-
-  event->type = type;
-  event->data.transfer.trq = trq;
-
-  // Push to lock-free queue (always succeeds since pool size == queue size)
-  client->event_queue.push(event);
-}
-
 // CALLBACK CONTEXT: USB task (called from usb_host_client_handle_events in USB task)
 static void control_callback(const usb_transfer_t *xfer) {
   auto *trq = static_cast<TransferRequest *>(xfer->context);
@@ -346,8 +321,9 @@ static void control_callback(const usb_transfer_t *xfer) {
     trq->callback(trq->status);
   }
 
-  // Queue cleanup to main loop
-  queue_transfer_cleanup(trq, EVENT_CONTROL_COMPLETE);
+  // Release transfer slot immediately in USB task
+  // The release_trq() uses thread-safe atomic operations
+  trq->client->release_trq(trq);
 }
 
 // THREAD CONTEXT: Called from both USB task and main loop threads (multi-consumer)
@@ -358,20 +334,20 @@ static void control_callback(const usb_transfer_t *xfer) {
 // This multi-threaded access is intentional for performance - USB task can
 // immediately restart transfers without waiting for main loop scheduling.
 TransferRequest *USBClient::get_trq_() {
-  uint16_t mask = this->trq_in_use_.load(std::memory_order_relaxed);
+  trq_bitmask_t mask = this->trq_in_use_.load(std::memory_order_relaxed);
 
   // Find first available slot (bit = 0) and try to claim it atomically
   // We use a while loop to allow retrying the same slot after CAS failure
   size_t i = 0;
   while (i != MAX_REQUESTS) {
-    if (mask & (1U << i)) {
+    if (mask & (static_cast<trq_bitmask_t>(1) << i)) {
       // Slot is in use, move to next slot
       i++;
       continue;
     }
 
     // Slot i appears available, try to claim it atomically
-    uint16_t desired = mask | (1U << i);  // Set bit i to mark as in-use
+    trq_bitmask_t desired = mask | (static_cast<trq_bitmask_t>(1) << i);  // Set bit i to mark as in-use
 
     if (this->trq_in_use_.compare_exchange_weak(mask, desired, std::memory_order_acquire, std::memory_order_relaxed)) {
       // Successfully claimed slot i - prepare the TransferRequest
@@ -386,7 +362,7 @@ TransferRequest *USBClient::get_trq_() {
     i = 0;
   }
 
-  ESP_LOGE(TAG, "All %d transfer slots in use", MAX_REQUESTS);
+  ESP_LOGE(TAG, "All %zu transfer slots in use", MAX_REQUESTS);
   return nullptr;
 }
 void USBClient::disconnect() {
@@ -452,8 +428,11 @@ static void transfer_callback(usb_transfer_t *xfer) {
     trq->callback(trq->status);
   }
 
-  // Queue cleanup to main loop
-  queue_transfer_cleanup(trq, EVENT_TRANSFER_COMPLETE);
+  // Release transfer slot AFTER callback completes to prevent slot exhaustion
+  // This is critical for high-throughput transfers (e.g., USB UART at 115200 baud)
+  // The callback has finished accessing xfer->data_buffer, so it's safe to release
+  // The release_trq() uses thread-safe atomic operations
+  trq->client->release_trq(trq);
 }
 /**
  * Performs a transfer input operation.
@@ -521,12 +500,12 @@ void USBClient::dump_config() {
                 "  Product id %04X",
                 this->vid_, this->pid_);
 }
-// THREAD CONTEXT: Only called from main loop thread (single producer for deallocation)
-// - Via event processing when handling EVENT_TRANSFER_COMPLETE/EVENT_CONTROL_COMPLETE
-// - Directly when transfer submission fails
+// THREAD CONTEXT: Called from both USB task and main loop threads
+// - USB task: Immediately after transfer callback completes
+// - Main loop: When transfer submission fails
 //
 // THREAD SAFETY: Lock-free using atomic AND to clear bit
-// Single-producer pattern makes this simpler than allocation
+// Thread-safe atomic operation allows multi-threaded deallocation
 void USBClient::release_trq(TransferRequest *trq) {
   if (trq == nullptr)
     return;
@@ -540,8 +519,8 @@ void USBClient::release_trq(TransferRequest *trq) {
 
   // Atomically clear bit i to mark slot as available
   // fetch_and with inverted bitmask clears the bit atomically
-  uint16_t bit = 1U << index;
-  this->trq_in_use_.fetch_and(static_cast<uint16_t>(~bit), std::memory_order_release);
+  trq_bitmask_t bit = static_cast<trq_bitmask_t>(1) << index;
+  this->trq_in_use_.fetch_and(static_cast<trq_bitmask_t>(~bit), std::memory_order_release);
 }
 
 }  // namespace usb_host

esphome/components/web_server/list_entities.cpp

@@ -19,72 +19,54 @@ ListEntitiesIterator::~ListEntitiesIterator() {}
 
 #ifdef USE_BINARY_SENSOR
 bool ListEntitiesIterator::on_binary_sensor(binary_sensor::BinarySensor *obj) {
-  if (this->events_->count() == 0)
-    return true;
   this->events_->deferrable_send_state(obj, "state_detail_all", WebServer::binary_sensor_all_json_generator);
   return true;
 }
 #endif
 #ifdef USE_COVER
 bool ListEntitiesIterator::on_cover(cover::Cover *obj) {
-  if (this->events_->count() == 0)
-    return true;
   this->events_->deferrable_send_state(obj, "state_detail_all", WebServer::cover_all_json_generator);
   return true;
 }
 #endif
 #ifdef USE_FAN
 bool ListEntitiesIterator::on_fan(fan::Fan *obj) {
-  if (this->events_->count() == 0)
-    return true;
   this->events_->deferrable_send_state(obj, "state_detail_all", WebServer::fan_all_json_generator);
   return true;
 }
 #endif
 #ifdef USE_LIGHT
 bool ListEntitiesIterator::on_light(light::LightState *obj) {
-  if (this->events_->count() == 0)
-    return true;
   this->events_->deferrable_send_state(obj, "state_detail_all", WebServer::light_all_json_generator);
   return true;
 }
 #endif
 #ifdef USE_SENSOR
 bool ListEntitiesIterator::on_sensor(sensor::Sensor *obj) {
-  if (this->events_->count() == 0)
-    return true;
   this->events_->deferrable_send_state(obj, "state_detail_all", WebServer::sensor_all_json_generator);
   return true;
 }
 #endif
 #ifdef USE_SWITCH
 bool ListEntitiesIterator::on_switch(switch_::Switch *obj) {
-  if (this->events_->count() == 0)
-    return true;
   this->events_->deferrable_send_state(obj, "state_detail_all", WebServer::switch_all_json_generator);
   return true;
 }
 #endif
 #ifdef USE_BUTTON
 bool ListEntitiesIterator::on_button(button::Button *obj) {
-  if (this->events_->count() == 0)
-    return true;
   this->events_->deferrable_send_state(obj, "state_detail_all", WebServer::button_all_json_generator);
   return true;
 }
 #endif
 #ifdef USE_TEXT_SENSOR
 bool ListEntitiesIterator::on_text_sensor(text_sensor::TextSensor *obj) {
-  if (this->events_->count() == 0)
-    return true;
   this->events_->deferrable_send_state(obj, "state_detail_all", WebServer::text_sensor_all_json_generator);
   return true;
 }
 #endif
 #ifdef USE_LOCK
 bool ListEntitiesIterator::on_lock(lock::Lock *obj) {
-  if (this->events_->count() == 0)
-    return true;
   this->events_->deferrable_send_state(obj, "state_detail_all", WebServer::lock_all_json_generator);
   return true;
 }
@@ -92,8 +74,6 @@ bool ListEntitiesIterator::on_lock(lock::Lock *obj) {
 
 #ifdef USE_VALVE
 bool ListEntitiesIterator::on_valve(valve::Valve *obj) {
-  if (this->events_->count() == 0)
-    return true;
   this->events_->deferrable_send_state(obj, "state_detail_all", WebServer::valve_all_json_generator);
   return true;
 }
@@ -101,8 +81,6 @@ bool ListEntitiesIterator::on_valve(valve::Valve *obj) {
 
 #ifdef USE_CLIMATE
 bool ListEntitiesIterator::on_climate(climate::Climate *obj) {
-  if (this->events_->count() == 0)
-    return true;
   this->events_->deferrable_send_state(obj, "state_detail_all", WebServer::climate_all_json_generator);
   return true;
 }
@@ -110,8 +88,6 @@ bool ListEntitiesIterator::on_climate(climate::Climate *obj) {
 
 #ifdef USE_NUMBER
 bool ListEntitiesIterator::on_number(number::Number *obj) {
-  if (this->events_->count() == 0)
-    return true;
   this->events_->deferrable_send_state(obj, "state_detail_all", WebServer::number_all_json_generator);
   return true;
 }
@@ -119,8 +95,6 @@ bool ListEntitiesIterator::on_number(number::Number *obj) {
 
 #ifdef USE_DATETIME_DATE
 bool ListEntitiesIterator::on_date(datetime::DateEntity *obj) {
-  if (this->events_->count() == 0)
-    return true;
   this->events_->deferrable_send_state(obj, "state_detail_all", WebServer::date_all_json_generator);
   return true;
 }
@@ -128,8 +102,6 @@ bool ListEntitiesIterator::on_date(datetime::DateEntity *obj) {
 
 #ifdef USE_DATETIME_TIME
 bool ListEntitiesIterator::on_time(datetime::TimeEntity *obj) {
-  if (this->events_->count() == 0)
-    return true;
   this->events_->deferrable_send_state(obj, "state_detail_all", WebServer::time_all_json_generator);
   return true;
 }
@@ -137,8 +109,6 @@ bool ListEntitiesIterator::on_time(datetime::TimeEntity *obj) {
 
 #ifdef USE_DATETIME_DATETIME
 bool ListEntitiesIterator::on_datetime(datetime::DateTimeEntity *obj) {
-  if (this->events_->count() == 0)
-    return true;
   this->events_->deferrable_send_state(obj, "state_detail_all", WebServer::datetime_all_json_generator);
   return true;
 }
@@ -146,8 +116,6 @@ bool ListEntitiesIterator::on_datetime(datetime::DateTimeEntity *obj) {
 
 #ifdef USE_TEXT
 bool ListEntitiesIterator::on_text(text::Text *obj) {
-  if (this->events_->count() == 0)
-    return true;
   this->events_->deferrable_send_state(obj, "state_detail_all", WebServer::text_all_json_generator);
   return true;
 }
@@ -155,8 +123,6 @@ bool ListEntitiesIterator::on_text(text::Text *obj) {
 
 #ifdef USE_SELECT
 bool ListEntitiesIterator::on_select(select::Select *obj) {
-  if (this->events_->count() == 0)
-    return true;
   this->events_->deferrable_send_state(obj, "state_detail_all", WebServer::select_all_json_generator);
   return true;
 }
@@ -164,8 +130,6 @@ bool ListEntitiesIterator::on_select(select::Select *obj) {
 
 #ifdef USE_ALARM_CONTROL_PANEL
 bool ListEntitiesIterator::on_alarm_control_panel(alarm_control_panel::AlarmControlPanel *obj) {
-  if (this->events_->count() == 0)
-    return true;
   this->events_->deferrable_send_state(obj, "state_detail_all", WebServer::alarm_control_panel_all_json_generator);
   return true;
 }
@@ -173,8 +137,6 @@ bool ListEntitiesIterator::on_alarm_control_panel(alarm_control_panel::AlarmCont
 
 #ifdef USE_EVENT
 bool ListEntitiesIterator::on_event(event::Event *obj) {
-  if (this->events_->count() == 0)
-    return true;
   // Null event type, since we are just iterating over entities
   this->events_->deferrable_send_state(obj, "state_detail_all", WebServer::event_all_json_generator);
   return true;
@@ -183,8 +145,6 @@ bool ListEntitiesIterator::on_event(event::Event *obj) {
 
 #ifdef USE_UPDATE
 bool ListEntitiesIterator::on_update(update::UpdateEntity *obj) {
-  if (this->events_->count() == 0)
-    return true;
   this->events_->deferrable_send_state(obj, "state_detail_all", WebServer::update_all_json_generator);
   return true;
 }

esphome/components/web_server/web_server.cpp

@@ -152,6 +152,10 @@ void DeferredUpdateEventSource::loop() {
 
 void DeferredUpdateEventSource::deferrable_send_state(void *source, const char *event_type,
                                                       message_generator_t *message_generator) {
+  // Skip if no connected clients to avoid unnecessary deferred queue processing
+  if (this->count() == 0)
+    return;
+
   // allow all json "details_all" to go through before publishing bare state events, this avoids unnamed entries showing
   // up in the web GUI and reduces event load during initial connect
   if (!entities_iterator_.completed() && 0 != strcmp(event_type, "state_detail_all"))
@@ -197,6 +201,9 @@ void DeferredUpdateEventSourceList::loop() {
 
 void DeferredUpdateEventSourceList::deferrable_send_state(void *source, const char *event_type,
                                                           message_generator_t *message_generator) {
+  // Skip if no event sources (no connected clients) to avoid unnecessary iteration
+  if (this->empty())
+    return;
   for (DeferredUpdateEventSource *dues : *this) {
     dues->deferrable_send_state(source, event_type, message_generator);
   }
@@ -424,8 +431,6 @@ static JsonDetail get_request_detail(AsyncWebServerRequest *request) {
 
 #ifdef USE_SENSOR
 void WebServer::on_sensor_update(sensor::Sensor *obj, float state) {
-  if (this->events_.empty())
-    return;
   this->events_.deferrable_send_state(obj, "state", sensor_state_json_generator);
 }
 void WebServer::handle_sensor_request(AsyncWebServerRequest *request, const UrlMatch &match) {
@@ -453,13 +458,8 @@ std::string WebServer::sensor_json(sensor::Sensor *obj, float value, JsonDetail
 
   const auto uom_ref = obj->get_unit_of_measurement_ref();
 
-  // Build JSON directly inline
-  std::string state;
-  if (std::isnan(value)) {
-    state = "NA";
-  } else {
-    state = value_accuracy_with_uom_to_string(value, obj->get_accuracy_decimals(), uom_ref);
-  }
+  std::string state =
+      std::isnan(value) ? "NA" : value_accuracy_with_uom_to_string(value, obj->get_accuracy_decimals(), uom_ref);
   set_json_icon_state_value(root, obj, "sensor", state, value, start_config);
   if (start_config == DETAIL_ALL) {
     this->add_sorting_info_(root, obj);
@@ -473,8 +473,6 @@ std::string WebServer::sensor_json(sensor::Sensor *obj, float value, JsonDetail
 
 #ifdef USE_TEXT_SENSOR
 void WebServer::on_text_sensor_update(text_sensor::TextSensor *obj, const std::string &state) {
-  if (this->events_.empty())
-    return;
   this->events_.deferrable_send_state(obj, "state", text_sensor_state_json_generator);
 }
 void WebServer::handle_text_sensor_request(AsyncWebServerRequest *request, const UrlMatch &match) {
@@ -514,8 +512,6 @@ std::string WebServer::text_sensor_json(text_sensor::TextSensor *obj, const std:
 
 #ifdef USE_SWITCH
 void WebServer::on_switch_update(switch_::Switch *obj, bool state) {
-  if (this->events_.empty())
-    return;
   this->events_.deferrable_send_state(obj, "state", switch_state_json_generator);
 }
 void WebServer::handle_switch_request(AsyncWebServerRequest *request, const UrlMatch &match) {
@@ -627,8 +623,6 @@ std::string WebServer::button_json(button::Button *obj, JsonDetail start_config)
 
 #ifdef USE_BINARY_SENSOR
 void WebServer::on_binary_sensor_update(binary_sensor::BinarySensor *obj) {
-  if (this->events_.empty())
-    return;
   this->events_.deferrable_send_state(obj, "state", binary_sensor_state_json_generator);
 }
 void WebServer::handle_binary_sensor_request(AsyncWebServerRequest *request, const UrlMatch &match) {
@@ -667,8 +661,6 @@ std::string WebServer::binary_sensor_json(binary_sensor::BinarySensor *obj, bool
 
 #ifdef USE_FAN
 void WebServer::on_fan_update(fan::Fan *obj) {
-  if (this->events_.empty())
-    return;
   this->events_.deferrable_send_state(obj, "state", fan_state_json_generator);
 }
 void WebServer::handle_fan_request(AsyncWebServerRequest *request, const UrlMatch &match) {
@@ -743,8 +735,6 @@ std::string WebServer::fan_json(fan::Fan *obj, JsonDetail start_config) {
 
 #ifdef USE_LIGHT
 void WebServer::on_light_update(light::LightState *obj) {
-  if (this->events_.empty())
-    return;
   this->events_.deferrable_send_state(obj, "state", light_state_json_generator);
 }
 void WebServer::handle_light_request(AsyncWebServerRequest *request, const UrlMatch &match) {
@@ -800,8 +790,7 @@ std::string WebServer::light_json(light::LightState *obj, JsonDetail start_confi
   json::JsonBuilder builder;
   JsonObject root = builder.root();
 
-  set_json_id(root, obj, "light", start_config);
-  root["state"] = obj->remote_values.is_on() ? "ON" : "OFF";
+  set_json_value(root, obj, "light", obj->remote_values.is_on() ? "ON" : "OFF", start_config);
 
   light::LightJSONSchema::dump_json(*obj, root);
   if (start_config == DETAIL_ALL) {
@@ -819,8 +808,6 @@ std::string WebServer::light_json(light::LightState *obj, JsonDetail start_confi
 
 #ifdef USE_COVER
 void WebServer::on_cover_update(cover::Cover *obj) {
-  if (this->events_.empty())
-    return;
   this->events_.deferrable_send_state(obj, "state", cover_state_json_generator);
 }
 void WebServer::handle_cover_request(AsyncWebServerRequest *request, const UrlMatch &match) {
@@ -906,8 +893,6 @@ std::string WebServer::cover_json(cover::Cover *obj, JsonDetail start_config) {
 
 #ifdef USE_NUMBER
 void WebServer::on_number_update(number::Number *obj, float state) {
-  if (this->events_.empty())
-    return;
   this->events_.deferrable_send_state(obj, "state", number_state_json_generator);
 }
 void WebServer::handle_number_request(AsyncWebServerRequest *request, const UrlMatch &match) {
@@ -948,7 +933,13 @@ std::string WebServer::number_json(number::Number *obj, float value, JsonDetail
 
   const auto uom_ref = obj->traits.get_unit_of_measurement_ref();
 
-  set_json_id(root, obj, "number", start_config);
+  std::string val_str = std::isnan(value)
+                            ? "\"NaN\""
+                            : value_accuracy_to_string(value, step_to_accuracy_decimals(obj->traits.get_step()));
+  std::string state_str = std::isnan(value) ? "NA"
+                                            : value_accuracy_with_uom_to_string(
+                                                  value, step_to_accuracy_decimals(obj->traits.get_step()), uom_ref);
+  set_json_icon_state_value(root, obj, "number", state_str, val_str, start_config);
   if (start_config == DETAIL_ALL) {
     root["min_value"] =
         value_accuracy_to_string(obj->traits.get_min_value(), step_to_accuracy_decimals(obj->traits.get_step()));
@@ -960,14 +951,6 @@ std::string WebServer::number_json(number::Number *obj, float value, JsonDetail
       root["uom"] = uom_ref;
     this->add_sorting_info_(root, obj);
   }
-  if (std::isnan(value)) {
-    root["value"] = "\"NaN\"";
-    root["state"] = "NA";
-  } else {
-    root["value"] = value_accuracy_to_string(value, step_to_accuracy_decimals(obj->traits.get_step()));
-    root["state"] =
-        value_accuracy_with_uom_to_string(value, step_to_accuracy_decimals(obj->traits.get_step()), uom_ref);
-  }
 
   return builder.serialize();
 }
@@ -975,8 +958,6 @@ std::string WebServer::number_json(number::Number *obj, float value, JsonDetail
 
 #ifdef USE_DATETIME_DATE
 void WebServer::on_date_update(datetime::DateEntity *obj) {
-  if (this->events_.empty())
-    return;
   this->events_.deferrable_send_state(obj, "state", date_state_json_generator);
 }
 void WebServer::handle_date_request(AsyncWebServerRequest *request, const UrlMatch &match) {
@@ -1020,10 +1001,8 @@ std::string WebServer::date_json(datetime::DateEntity *obj, JsonDetail start_con
   json::JsonBuilder builder;
   JsonObject root = builder.root();
 
-  set_json_id(root, obj, "date", start_config);
   std::string value = str_sprintf("%d-%02d-%02d", obj->year, obj->month, obj->day);
-  root["value"] = value;
-  root["state"] = value;
+  set_json_icon_state_value(root, obj, "date", value, value, start_config);
   if (start_config == DETAIL_ALL) {
     this->add_sorting_info_(root, obj);
   }
@@ -1034,8 +1013,6 @@ std::string WebServer::date_json(datetime::DateEntity *obj, JsonDetail start_con
 
 #ifdef USE_DATETIME_TIME
 void WebServer::on_time_update(datetime::TimeEntity *obj) {
-  if (this->events_.empty())
-    return;
   this->events_.deferrable_send_state(obj, "state", time_state_json_generator);
 }
 void WebServer::handle_time_request(AsyncWebServerRequest *request, const UrlMatch &match) {
@@ -1078,10 +1055,8 @@ std::string WebServer::time_json(datetime::TimeEntity *obj, JsonDetail start_con
   json::JsonBuilder builder;
   JsonObject root = builder.root();
 
-  set_json_id(root, obj, "time", start_config);
   std::string value = str_sprintf("%02d:%02d:%02d", obj->hour, obj->minute, obj->second);
-  root["value"] = value;
-  root["state"] = value;
+  set_json_icon_state_value(root, obj, "time", value, value, start_config);
   if (start_config == DETAIL_ALL) {
     this->add_sorting_info_(root, obj);
   }
@@ -1092,8 +1067,6 @@ std::string WebServer::time_json(datetime::TimeEntity *obj, JsonDetail start_con
 
 #ifdef USE_DATETIME_DATETIME
 void WebServer::on_datetime_update(datetime::DateTimeEntity *obj) {
-  if (this->events_.empty())
-    return;
   this->events_.deferrable_send_state(obj, "state", datetime_state_json_generator);
 }
 void WebServer::handle_datetime_request(AsyncWebServerRequest *request, const UrlMatch &match) {
@@ -1136,11 +1109,9 @@ std::string WebServer::datetime_json(datetime::DateTimeEntity *obj, JsonDetail s
   json::JsonBuilder builder;
   JsonObject root = builder.root();
 
-  set_json_id(root, obj, "datetime", start_config);
   std::string value =
       str_sprintf("%d-%02d-%02d %02d:%02d:%02d", obj->year, obj->month, obj->day, obj->hour, obj->minute, obj->second);
-  root["value"] = value;
-  root["state"] = value;
+  set_json_icon_state_value(root, obj, "datetime", value, value, start_config);
   if (start_config == DETAIL_ALL) {
     this->add_sorting_info_(root, obj);
   }
@@ -1151,8 +1122,6 @@ std::string WebServer::datetime_json(datetime::DateTimeEntity *obj, JsonDetail s
 
 #ifdef USE_TEXT
 void WebServer::on_text_update(text::Text *obj, const std::string &state) {
-  if (this->events_.empty())
-    return;
   this->events_.deferrable_send_state(obj, "state", text_state_json_generator);
 }
 void WebServer::handle_text_request(AsyncWebServerRequest *request, const UrlMatch &match) {
@@ -1191,16 +1160,11 @@ std::string WebServer::text_json(text::Text *obj, const std::string &value, Json
   json::JsonBuilder builder;
   JsonObject root = builder.root();
 
-  set_json_id(root, obj, "text", start_config);
+  std::string state = obj->traits.get_mode() == text::TextMode::TEXT_MODE_PASSWORD ? "********" : value;
+  set_json_icon_state_value(root, obj, "text", state, value, start_config);
   root["min_length"] = obj->traits.get_min_length();
   root["max_length"] = obj->traits.get_max_length();
   root["pattern"] = obj->traits.get_pattern();
-  if (obj->traits.get_mode() == text::TextMode::TEXT_MODE_PASSWORD) {
-    root["state"] = "********";
-  } else {
-    root["state"] = value;
-  }
-  root["value"] = value;
   if (start_config == DETAIL_ALL) {
     root["mode"] = (int) obj->traits.get_mode();
     this->add_sorting_info_(root, obj);
@@ -1212,8 +1176,6 @@ std::string WebServer::text_json(text::Text *obj, const std::string &value, Json
 
 #ifdef USE_SELECT
 void WebServer::on_select_update(select::Select *obj, const std::string &state, size_t index) {
-  if (this->events_.empty())
-    return;
   this->events_.deferrable_send_state(obj, "state", select_state_json_generator);
 }
 void WebServer::handle_select_request(AsyncWebServerRequest *request, const UrlMatch &match) {
@@ -1270,8 +1232,6 @@ std::string WebServer::select_json(select::Select *obj, const std::string &value
 
 #ifdef USE_CLIMATE
 void WebServer::on_climate_update(climate::Climate *obj) {
-  if (this->events_.empty())
-    return;
   this->events_.deferrable_send_state(obj, "state", climate_state_json_generator);
 }
 void WebServer::handle_climate_request(AsyncWebServerRequest *request, const UrlMatch &match) {
@@ -1412,8 +1372,6 @@ std::string WebServer::climate_json(climate::Climate *obj, JsonDetail start_conf
 
 #ifdef USE_LOCK
 void WebServer::on_lock_update(lock::Lock *obj) {
-  if (this->events_.empty())
-    return;
   this->events_.deferrable_send_state(obj, "state", lock_state_json_generator);
 }
 void WebServer::handle_lock_request(AsyncWebServerRequest *request, const UrlMatch &match) {
@@ -1485,8 +1443,6 @@ std::string WebServer::lock_json(lock::Lock *obj, lock::LockState value, JsonDet
 
 #ifdef USE_VALVE
 void WebServer::on_valve_update(valve::Valve *obj) {
-  if (this->events_.empty())
-    return;
   this->events_.deferrable_send_state(obj, "state", valve_state_json_generator);
 }
 void WebServer::handle_valve_request(AsyncWebServerRequest *request, const UrlMatch &match) {
@@ -1568,8 +1524,6 @@ std::string WebServer::valve_json(valve::Valve *obj, JsonDetail start_config) {
 
 #ifdef USE_ALARM_CONTROL_PANEL
 void WebServer::on_alarm_control_panel_update(alarm_control_panel::AlarmControlPanel *obj) {
-  if (this->events_.empty())
-    return;
   this->events_.deferrable_send_state(obj, "state", alarm_control_panel_state_json_generator);
 }
 void WebServer::handle_alarm_control_panel_request(AsyncWebServerRequest *request, const UrlMatch &match) {
@@ -1714,8 +1668,6 @@ static const char *update_state_to_string(update::UpdateState state) {
 }
 
 void WebServer::on_update(update::UpdateEntity *obj) {
-  if (this->events_.empty())
-    return;
   this->events_.deferrable_send_state(obj, "state", update_state_json_generator);
 }
 void WebServer::handle_update_request(AsyncWebServerRequest *request, const UrlMatch &match) {
@@ -1754,9 +1706,8 @@ std::string WebServer::update_json(update::UpdateEntity *obj, JsonDetail start_c
   json::JsonBuilder builder;
   JsonObject root = builder.root();
 
-  set_json_id(root, obj, "update", start_config);
-  root["value"] = obj->update_info.latest_version;
-  root["state"] = update_state_to_string(obj->state);
+  set_json_icon_state_value(root, obj, "update", update_state_to_string(obj->state), obj->update_info.latest_version,
+                            start_config);
   if (start_config == DETAIL_ALL) {
     root["current_version"] = obj->update_info.current_version;
     root["title"] = obj->update_info.title;

esphome/components/web_server_idf/web_server_idf.cpp

@@ -412,6 +412,9 @@ void AsyncEventSource::try_send_nodefer(const char *message, const char *event,
 
 void AsyncEventSource::deferrable_send_state(void *source, const char *event_type,
                                              message_generator_t *message_generator) {
+  // Skip if no connected clients to avoid unnecessary processing
+  if (this->empty())
+    return;
   for (auto *ses : this->sessions_) {
     if (ses->fd_.load() != 0) {  // Skip dead sessions
       ses->deferrable_send_state(source, event_type, message_generator);

esphome/components/wifi/wifi_component.cpp

@@ -267,7 +267,9 @@ network::IPAddress WiFiComponent::get_dns_address(int num) {
 }
 std::string WiFiComponent::get_use_address() const {
   if (this->use_address_.empty()) {
-    return App.get_name() + ".local";
+    // ".local" suffix length for mDNS hostnames
+    constexpr size_t mdns_local_suffix_len = 5;
+    return make_name_with_suffix(App.get_name(), '.', "local", mdns_local_suffix_len);
   }
   return this->use_address_;
 }
@@ -576,8 +578,9 @@ __attribute__((noinline)) static void log_scan_result(const WiFiScanResult &res)
   format_mac_addr_upper(bssid.data(), bssid_s);
 
   if (res.get_matches()) {
-    ESP_LOGI(TAG, "- '%s' %s" LOG_SECRET("(%s) ") "%s", res.get_ssid().c_str(), res.get_is_hidden() ? "(HIDDEN) " : "",
-             bssid_s, LOG_STR_ARG(get_signal_bars(res.get_rssi())));
+    ESP_LOGI(TAG, "- '%s' %s" LOG_SECRET("(%s) ") "%s", res.get_ssid().c_str(),
+             res.get_is_hidden() ? LOG_STR_LITERAL("(HIDDEN) ") : LOG_STR_LITERAL(""), bssid_s,
+             LOG_STR_ARG(get_signal_bars(res.get_rssi())));
     ESP_LOGD(TAG,
              "    Channel: %u\n"
              "    RSSI: %d dB",

esphome/config.py

@@ -647,7 +647,7 @@ class AddDynamicAutoLoadsValidationStep(ConfigValidationStep):
     """
 
     # Has to happen after normal schema is validated and before final schema validation
-    priority = -10.0
+    priority = -5.0
 
     def __init__(self, path: ConfigPath, comp: ComponentManifest) -> None:
         self.path = path

esphome/config_validation.py

@@ -1195,6 +1195,13 @@ def validate_bytes(value):
 
 
 def hostname(value):
+    """Validate that the value is a valid hostname.
+
+    Maximum length is 63 characters per RFC 1035.
+
+    Note: If this limit is changed, update MAX_NAME_WITH_SUFFIX_SIZE in
+    esphome/core/helpers.cpp to accommodate the new maximum length.
+    """
     value = string(value)
     if re.match(r"^[a-z0-9-]{1,63}$", value, re.IGNORECASE) is not None:
         return value

esphome/const.py

@@ -4,7 +4,7 @@ from enum import Enum
 
 from esphome.enum import StrEnum
 
-__version__ = "2025.10.0-dev"
+__version__ = "2025.11.0-dev"
 
 ALLOWED_NAME_CHARS = "abcdefghijklmnopqrstuvwxyz0123456789-_"
 VALID_SUBSTITUTIONS_CHARACTERS = (

esphome/core/__init__.py

@@ -529,6 +529,8 @@ class EsphomeCore:
         self.dashboard = False
         # True if command is run from vscode api
         self.vscode = False
+        # True if running in testing mode (disables validation checks for grouped testing)
+        self.testing_mode = False
         # The name of the node
         self.name: str | None = None
         # The friendly name of the node

esphome/core/application.cpp

@@ -340,8 +340,8 @@ void Application::calculate_looping_components_() {
     }
   }
 
-  // Pre-reserve vector to avoid reallocations
-  this->looping_components_.reserve(total_looping);
+  // Initialize FixedVector with exact size - no reallocation possible
+  this->looping_components_.init(total_looping);
 
   // Add all components with loop override that aren't already LOOP_DONE
   // Some components (like logger) may call disable_loop() during initialization

esphome/core/application.h

@@ -102,9 +102,15 @@ class Application {
     arch_init();
     this->name_add_mac_suffix_ = name_add_mac_suffix;
     if (name_add_mac_suffix) {
-      const std::string mac_suffix = get_mac_address().substr(6);
-      this->name_ = name + "-" + mac_suffix;
-      this->friendly_name_ = friendly_name.empty() ? "" : friendly_name + " " + mac_suffix;
+      // MAC address suffix length (last 6 characters of 12-char MAC address string)
+      constexpr size_t mac_address_suffix_len = 6;
+      const std::string mac_addr = get_mac_address();
+      // Use pointer + offset to avoid substr() allocation
+      const char *mac_suffix_ptr = mac_addr.c_str() + mac_address_suffix_len;
+      this->name_ = make_name_with_suffix(name, '-', mac_suffix_ptr, mac_address_suffix_len);
+      if (!friendly_name.empty()) {
+        this->friendly_name_ = make_name_with_suffix(friendly_name, ' ', mac_suffix_ptr, mac_address_suffix_len);
+      }
     } else {
       this->name_ = name;
       this->friendly_name_ = friendly_name;
@@ -472,7 +478,7 @@ class Application {
   // - When a component is enabled, it's swapped with the first inactive component
   //   and active_end_ is incremented
   // - This eliminates branch mispredictions from flag checking in the hot loop
-  std::vector<Component *> looping_components_{};
+  FixedVector<Component *> looping_components_{};
 #ifdef USE_SOCKET_SELECT_SUPPORT
   std::vector<int> socket_fds_;  // Vector of all monitored socket file descriptors
 #endif

esphome/core/config.py

@@ -200,7 +200,7 @@ CONFIG_SCHEMA = cv.All(
     cv.Schema(
         {
             cv.Required(CONF_NAME): cv.valid_name,
-            cv.Optional(CONF_FRIENDLY_NAME, ""): cv.string,
+            cv.Optional(CONF_FRIENDLY_NAME, ""): cv.All(cv.string, cv.Length(max=120)),
             cv.Optional(CONF_AREA): validate_area_config,
             cv.Optional(CONF_COMMENT): cv.string,
             cv.Required(CONF_BUILD_PATH): cv.string,

esphome/core/defines.h

@@ -83,7 +83,9 @@
 #define USE_LVGL_TILEVIEW
 #define USE_LVGL_TOUCHSCREEN
 #define USE_MDNS
+#define USE_MDNS_STORE_SERVICES
 #define MDNS_SERVICE_COUNT 3
+#define MDNS_DYNAMIC_TXT_COUNT 3
 #define USE_MEDIA_PLAYER
 #define USE_NEXTION_TFT_UPLOAD
 #define USE_NUMBER
@@ -174,6 +176,8 @@
 #define USE_ESP32_BLE_SERVER_DESCRIPTOR_ON_WRITE
 #define USE_ESP32_BLE_SERVER_ON_CONNECT
 #define USE_ESP32_BLE_SERVER_ON_DISCONNECT
+#define ESPHOME_ESP32_BLE_TRACKER_LISTENER_COUNT 1
+#define ESPHOME_ESP32_BLE_TRACKER_CLIENT_COUNT 1
 #define USE_ESP32_CAMERA_JPEG_ENCODER
 #define USE_I2C
 #define USE_IMPROV
@@ -190,6 +194,7 @@
 #define USE_WEBSERVER_PORT 80  // NOLINT
 #define USE_WEBSERVER_SORTING
 #define USE_WIFI_11KV_SUPPORT
+#define USB_HOST_MAX_REQUESTS 16
 
 #ifdef USE_ARDUINO
 #define USE_ARDUINO_VERSION_CODE VERSION_CODE(3, 2, 1)

esphome/core/entity_helpers.py

@@ -246,12 +246,15 @@ def entity_duplicate_validator(platform: str) -> Callable[[ConfigType], ConfigTy
                     "\n          to distinguish them"
                 )
 
-            raise cv.Invalid(
-                f"Duplicate {platform} entity with name '{entity_name}' found{device_prefix}. "
-                f"{conflict_msg}. "
-                "Each entity on a device must have a unique name within its platform."
-                f"{sanitized_msg}"
-            )
+            # Skip duplicate entity name validation when testing_mode is enabled
+            # This flag is used for grouped component testing
+            if not CORE.testing_mode:
+                raise cv.Invalid(
+                    f"Duplicate {platform} entity with name '{entity_name}' found{device_prefix}. "
+                    f"{conflict_msg}. "
+                    "Each entity on a device must have a unique name within its platform."
+                    f"{sanitized_msg}"
+                )
 
         # Store metadata about this entity
         entity_metadata: EntityMetadata = {

esphome/core/helpers.cpp

@@ -235,6 +235,30 @@ std::string str_sprintf(const char *fmt, ...) {
   return str;
 }
 
+// Maximum size for name with suffix: 120 (max friendly name) + 1 (separator) + 6 (MAC suffix) + 1 (null term)
+static constexpr size_t MAX_NAME_WITH_SUFFIX_SIZE = 128;
+
+std::string make_name_with_suffix(const std::string &name, char sep, const char *suffix_ptr, size_t suffix_len) {
+  char buffer[MAX_NAME_WITH_SUFFIX_SIZE];
+  size_t name_len = name.size();
+  size_t total_len = name_len + 1 + suffix_len;
+
+  // Silently truncate if needed: prioritize keeping the full suffix
+  if (total_len >= MAX_NAME_WITH_SUFFIX_SIZE) {
+    // NOTE: This calculation could underflow if suffix_len >= MAX_NAME_WITH_SUFFIX_SIZE - 2,
+    // but this is safe because this helper is only called with small suffixes:
+    // MAC suffixes (6-12 bytes), ".local" (5 bytes), etc.
+    name_len = MAX_NAME_WITH_SUFFIX_SIZE - suffix_len - 2;  // -2 for separator and null terminator
+    total_len = name_len + 1 + suffix_len;
+  }
+
+  memcpy(buffer, name.c_str(), name_len);
+  buffer[name_len] = sep;
+  memcpy(buffer + name_len + 1, suffix_ptr, suffix_len);
+  buffer[total_len] = '\0';
+  return std::string(buffer, total_len);
+}
+
 // Parsing & formatting
 
 size_t parse_hex(const char *str, size_t length, uint8_t *data, size_t count) {

esphome/core/helpers.h

@@ -162,6 +162,54 @@ template<typename T, size_t N> class StaticVector {
   const_reverse_iterator rend() const { return const_reverse_iterator(begin()); }
 };
 
+/// Fixed-capacity vector - allocates once at runtime, never reallocates
+/// This avoids std::vector template overhead (_M_realloc_insert, _M_default_append)
+/// when size is known at initialization but not at compile time
+template<typename T> class FixedVector {
+ private:
+  T *data_{nullptr};
+  size_t size_{0};
+  size_t capacity_{0};
+
+ public:
+  FixedVector() = default;
+
+  ~FixedVector() {
+    if (data_ != nullptr) {
+      delete[] data_;
+    }
+  }
+
+  // Disable copy to avoid accidental copies
+  FixedVector(const FixedVector &) = delete;
+  FixedVector &operator=(const FixedVector &) = delete;
+
+  // Allocate capacity - can only be called once on empty vector
+  void init(size_t n) {
+    if (data_ == nullptr && n > 0) {
+      data_ = new T[n];
+      capacity_ = n;
+      size_ = 0;
+    }
+  }
+
+  /// Add element without bounds checking
+  /// Caller must ensure sufficient capacity was allocated via init()
+  /// Silently ignores pushes beyond capacity (no exception or assertion)
+  void push_back(const T &value) {
+    if (size_ < capacity_) {
+      data_[size_++] = value;
+    }
+  }
+
+  size_t size() const { return size_; }
+
+  /// Access element without bounds checking (matches std::vector behavior)
+  /// Caller must ensure index is valid (i < size())
+  T &operator[](size_t i) { return data_[i]; }
+  const T &operator[](size_t i) const { return data_[i]; }
+};
+
 ///@}
 
 /// @name Mathematics
@@ -309,6 +357,16 @@ std::string __attribute__((format(printf, 1, 3))) str_snprintf(const char *fmt,
 /// sprintf-like function returning std::string.
 std::string __attribute__((format(printf, 1, 2))) str_sprintf(const char *fmt, ...);
 
+/// Concatenate a name with a separator and suffix using an efficient stack-based approach.
+/// This avoids multiple heap allocations during string construction.
+/// Maximum name length supported is 120 characters for friendly names.
+/// @param name The base name string
+/// @param sep The separator character (e.g., '-', ' ', or '.')
+/// @param suffix_ptr Pointer to the suffix characters
+/// @param suffix_len Length of the suffix
+/// @return The concatenated string: name + sep + suffix
+std::string make_name_with_suffix(const std::string &name, char sep, const char *suffix_ptr, size_t suffix_len);
+
 ///@}
 
 /// @name Parsing & formatting

esphome/espota2.py

@@ -410,7 +410,7 @@ def run_ota_impl_(
         af, socktype, _, _, sa = r
         _LOGGER.info("Connecting to %s port %s...", sa[0], sa[1])
         sock = socket.socket(af, socktype)
-        sock.settimeout(10.0)
+        sock.settimeout(20.0)
         try:
             sock.connect(sa)
         except OSError as err:

esphome/pins.py

@@ -118,11 +118,11 @@ class PinRegistry(dict):
                         parent_config = fconf.get_config_for_path(parent_path)
                         final_val_fun(pin_config, parent_config)
                     allow_others = pin_config.get(CONF_ALLOW_OTHER_USES, False)
-                    if count != 1 and not allow_others:
+                    if count != 1 and not allow_others and not CORE.testing_mode:
                         raise cv.Invalid(
                             f"Pin {pin_config[CONF_NUMBER]} is used in multiple places"
                         )
-                    if count == 1 and allow_others:
+                    if count == 1 and allow_others and not CORE.testing_mode:
                         raise cv.Invalid(
                             f"Pin {pin_config[CONF_NUMBER]} incorrectly sets {CONF_ALLOW_OTHER_USES}: true"
                         )

esphome/platformio_api.py

@@ -43,6 +43,35 @@ def patch_structhash():
     cli.clean_build_dir = patched_clean_build_dir
 
 
+def patch_file_downloader():
+    """Patch PlatformIO's FileDownloader to retry on PackageException errors."""
+    from platformio.package.download import FileDownloader
+    from platformio.package.exception import PackageException
+
+    original_init = FileDownloader.__init__
+
+    def patched_init(self, *args: Any, **kwargs: Any) -> None:
+        max_retries = 3
+
+        for attempt in range(max_retries):
+            try:
+                return original_init(self, *args, **kwargs)
+            except PackageException as e:
+                if attempt < max_retries - 1:
+                    _LOGGER.warning(
+                        "Package download failed: %s. Retrying... (attempt %d/%d)",
+                        str(e),
+                        attempt + 1,
+                        max_retries,
+                    )
+                else:
+                    # Final attempt - re-raise
+                    raise
+        return None
+
+    FileDownloader.__init__ = patched_init
+
+
 IGNORE_LIB_WARNINGS = f"(?:{'|'.join(['Hash', 'Update'])})"
 FILTER_PLATFORMIO_LINES = [
     r"Verbose mode can be enabled via `-v, --verbose` option.*",
@@ -75,6 +104,9 @@ FILTER_PLATFORMIO_LINES = [
     r"Creating BIN file .*",
     r"Warning! Could not find file \".*.crt\"",
     r"Warning! Arduino framework as an ESP-IDF component doesn't handle the `variant` field! The default `esp32` variant will be used.",
+    r"Warning: DEPRECATED: 'esptool.py' is deprecated. Please use 'esptool' instead. The '.py' suffix will be removed in a future major release.",
+    r"Warning: esp-idf-size exited with code 2",
+    r"esp_idf_size: error: unrecognized arguments: --ng",
 ]
 
 
@@ -97,6 +129,7 @@ def run_platformio_cli(*args, **kwargs) -> str | int:
     import platformio.__main__
 
     patch_structhash()
+    patch_file_downloader()
     return run_external_command(platformio.__main__.main, *cmd, **kwargs)
 
 

platformio.ini

@@ -147,7 +147,7 @@ lib_deps =
     makuna/NeoPixelBus@2.8.0             ; neopixelbus
     esphome/ESP32-audioI2S@2.3.0         ; i2s_audio
     droscy/esp_wireguard@0.4.2           ; wireguard
-    esphome/esp-audio-libs@1.1.4         ; audio
+    esphome/esp-audio-libs@2.0.1         ; audio
 
 build_flags =
     ${common:arduino.build_flags}
@@ -170,7 +170,7 @@ lib_deps =
     ${common:idf.lib_deps}
     droscy/esp_wireguard@0.4.2              ; wireguard
     kahrendt/ESPMicroSpeechFeatures@1.1.0   ; micro_wake_word
-    esphome/esp-audio-libs@1.1.4            ; audio
+    esphome/esp-audio-libs@2.0.1            ; audio
 build_flags =
     ${common:idf.build_flags}
     -Wno-nonnull-compare

requirements.txt

@@ -11,8 +11,8 @@ pyserial==3.5
 platformio==6.1.18  # When updating platformio, also update /docker/Dockerfile
 esptool==5.1.0
 click==8.1.7
-esphome-dashboard==20250904.0
-aioesphomeapi==41.11.0
+esphome-dashboard==20251009.0
+aioesphomeapi==41.13.0
 zeroconf==0.148.0
 puremagic==1.30
 ruamel.yaml==0.18.15 # dashboard_import

requirements_test.txt

@@ -1,7 +1,7 @@
 pylint==3.3.9
 flake8==7.3.0  # also change in .pre-commit-config.yaml when updating
-ruff==0.13.3  # also change in .pre-commit-config.yaml when updating
-pyupgrade==3.20.0  # also change in .pre-commit-config.yaml when updating
+ruff==0.14.0  # also change in .pre-commit-config.yaml when updating
+pyupgrade==3.21.0  # also change in .pre-commit-config.yaml when updating
 pre-commit
 
 # Unit tests

script/analyze_component_buses.py

@@ -0,0 +1,523 @@
+#!/usr/bin/env python3
+"""Analyze component test files to detect which common bus configs they use.
+
+This script scans component test files and extracts which common bus configurations
+(i2c, spi, uart, etc.) are included via the packages mechanism. This information
+is used to group components that can be tested together.
+
+Components can only be grouped together if they use the EXACT SAME set of common
+bus configurations, ensuring that merged configs are compatible.
+
+Example output:
+{
+    "component1": {
+        "esp32-ard": ["i2c", "uart_19200"],
+        "esp32-idf": ["i2c", "uart_19200"]
+    },
+    "component2": {
+        "esp32-ard": ["spi"],
+        "esp32-idf": ["spi"]
+    }
+}
+"""
+
+from __future__ import annotations
+
+import argparse
+from functools import lru_cache
+import json
+from pathlib import Path
+import re
+import sys
+from typing import Any
+
+# Add esphome to path
+sys.path.insert(0, str(Path(__file__).parent.parent))
+
+from esphome import yaml_util
+from esphome.config_helpers import Extend, Remove
+
+# Path to common bus configs
+COMMON_BUS_PATH = Path("tests/test_build_components/common")
+
+# Package dependencies - maps packages to the packages they include
+# When a component uses a package on the left, it automatically gets
+# the packages on the right as well
+PACKAGE_DEPENDENCIES = {
+    "modbus": ["uart"],  # modbus packages include uart packages
+    # Add more package dependencies here as needed
+}
+
+# Bus types that can be defined directly in config files
+# Components defining these directly cannot be grouped (they create unique bus IDs)
+DIRECT_BUS_TYPES = ("i2c", "spi", "uart", "modbus")
+
+# Signature for components with no bus requirements
+# These components can be merged with any other group
+NO_BUSES_SIGNATURE = "no_buses"
+
+# Base bus components - these ARE the bus implementations and should not
+# be flagged as needing migration since they are the platform/base components
+BASE_BUS_COMPONENTS = {
+    "i2c",
+    "spi",
+    "uart",
+    "modbus",
+    "canbus",
+}
+
+# Components that must be tested in isolation (not grouped or batched with others)
+# These have known build issues that prevent grouping
+# NOTE: This should be kept in sync with both test_build_components and split_components_for_ci.py
+ISOLATED_COMPONENTS = {
+    "animation": "Has display lambda in common.yaml that requires existing display platform - breaks when merged without display",
+    "esphome": "Defines devices/areas in esphome: section that are referenced in other sections - breaks when merged",
+    "ethernet": "Defines ethernet: which conflicts with wifi: used by most components",
+    "ethernet_info": "Related to ethernet component which conflicts with wifi",
+    "lvgl": "Defines multiple SDL displays on host platform that conflict when merged with other display configs",
+    "matrix_keypad": "Needs isolation due to keypad",
+    "mcp4725": "no YAML config to specify i2c bus id",
+    "mcp47a1": "no YAML config to specify i2c bus id",
+    "modbus_controller": "Defines multiple modbus buses for testing client/server functionality - conflicts with package modbus bus",
+    "neopixelbus": "RMT type conflict with ESP32 Arduino/ESP-IDF headers (enum vs struct rmt_channel_t)",
+    "packages": "cannot merge packages",
+}
+
+
+@lru_cache(maxsize=1)
+def get_common_bus_packages() -> frozenset[str]:
+    """Get the list of common bus package names.
+
+    Reads from tests/test_build_components/common/ directory
+    and caches the result. All bus types support component grouping
+    for config validation since --testing-mode bypasses runtime conflicts.
+
+    Returns:
+        Frozenset of common bus package names (i2c, spi, uart, etc.)
+    """
+    if not COMMON_BUS_PATH.exists():
+        return frozenset()
+
+    # List all directories in common/ - these are the bus package names
+    return frozenset(d.name for d in COMMON_BUS_PATH.iterdir() if d.is_dir())
+
+
+def uses_local_file_references(component_dir: Path) -> bool:
+    """Check if a component uses local file references via $component_dir.
+
+    Components that reference local files cannot be grouped because each needs
+    a unique component_dir path pointing to their specific directory.
+
+    Args:
+        component_dir: Path to the component's test directory
+
+    Returns:
+        True if the component uses $component_dir for local file references
+    """
+    common_yaml = component_dir / "common.yaml"
+    if not common_yaml.exists():
+        return False
+
+    try:
+        content = common_yaml.read_text()
+    except Exception:  # pylint: disable=broad-exception-caught
+        return False
+
+    # Pattern to match $component_dir or ${component_dir} references
+    # These indicate local file usage that prevents grouping
+    return bool(re.search(r"\$\{?component_dir\}?", content))
+
+
+def is_platform_component(component_dir: Path) -> bool:
+    """Check if a component is a platform component (abstract base class).
+
+    Platform components have IS_PLATFORM_COMPONENT = True and cannot be
+    instantiated without a platform-specific implementation. These components
+    define abstract methods and cause linker errors if compiled standalone.
+
+    Examples: canbus, mcp23x08_base, mcp23x17_base
+
+    Args:
+        component_dir: Path to the component's test directory
+
+    Returns:
+        True if this is a platform component
+    """
+    # Check in the actual component source, not tests
+    # tests/components/X -> tests/components -> tests -> repo root
+    repo_root = component_dir.parent.parent.parent
+    comp_init = (
+        repo_root / "esphome" / "components" / component_dir.name / "__init__.py"
+    )
+
+    if not comp_init.exists():
+        return False
+
+    try:
+        content = comp_init.read_text()
+        return "IS_PLATFORM_COMPONENT = True" in content
+    except Exception:  # pylint: disable=broad-exception-caught
+        return False
+
+
+def _contains_extend_or_remove(data: Any) -> bool:
+    """Recursively check if data contains Extend or Remove objects.
+
+    Args:
+        data: Parsed YAML data structure
+
+    Returns:
+        True if any Extend or Remove objects are found
+    """
+    if isinstance(data, (Extend, Remove)):
+        return True
+
+    if isinstance(data, dict):
+        for value in data.values():
+            if _contains_extend_or_remove(value):
+                return True
+
+    if isinstance(data, list):
+        for item in data:
+            if _contains_extend_or_remove(item):
+                return True
+
+    return False
+
+
+def analyze_yaml_file(yaml_file: Path) -> dict[str, Any]:
+    """Load a YAML file once and extract all needed information.
+
+    This loads the YAML file a single time and extracts all information needed
+    for component analysis, avoiding multiple file reads.
+
+    Args:
+        yaml_file: Path to the YAML file to analyze
+
+    Returns:
+        Dictionary with keys:
+        - buses: set of common bus package names
+        - has_extend_remove: bool indicating if Extend/Remove objects are present
+        - has_direct_bus_config: bool indicating if buses are defined directly (not via packages)
+        - loaded: bool indicating if file was successfully loaded
+    """
+    result = {
+        "buses": set(),
+        "has_extend_remove": False,
+        "has_direct_bus_config": False,
+        "loaded": False,
+    }
+
+    if not yaml_file.exists():
+        return result
+
+    try:
+        data = yaml_util.load_yaml(yaml_file)
+        result["loaded"] = True
+    except Exception:  # pylint: disable=broad-exception-caught
+        return result
+
+    # Check for Extend/Remove objects
+    result["has_extend_remove"] = _contains_extend_or_remove(data)
+
+    # Check if buses are defined directly (not via packages)
+    # Components that define i2c, spi, uart, or modbus directly in test files
+    # cannot be grouped because they create unique bus IDs
+    if isinstance(data, dict):
+        for bus_type in DIRECT_BUS_TYPES:
+            if bus_type in data:
+                result["has_direct_bus_config"] = True
+                break
+
+    # Extract common bus packages
+    if not isinstance(data, dict) or "packages" not in data:
+        return result
+
+    packages = data["packages"]
+    if not isinstance(packages, dict):
+        return result
+
+    valid_buses = get_common_bus_packages()
+    for pkg_name in packages:
+        if pkg_name not in valid_buses:
+            continue
+        result["buses"].add(pkg_name)
+        # Add any package dependencies (e.g., modbus includes uart)
+        if pkg_name not in PACKAGE_DEPENDENCIES:
+            continue
+        for dep in PACKAGE_DEPENDENCIES[pkg_name]:
+            if dep not in valid_buses:
+                continue
+            result["buses"].add(dep)
+
+    return result
+
+
+def analyze_component(component_dir: Path) -> tuple[dict[str, list[str]], bool, bool]:
+    """Analyze a component directory to find which buses each platform uses.
+
+    Args:
+        component_dir: Path to the component's test directory
+
+    Returns:
+        Tuple of:
+        - Dictionary mapping platform to list of bus configs
+          Example: {"esp32-ard": ["i2c", "spi"], "esp32-idf": ["i2c"]}
+        - Boolean indicating if component uses !extend or !remove
+        - Boolean indicating if component defines buses directly (not via packages)
+    """
+    if not component_dir.is_dir():
+        return {}, False, False
+
+    platform_buses = {}
+    has_extend_remove = False
+    has_direct_bus_config = False
+
+    # Analyze all YAML files in the component directory
+    for yaml_file in component_dir.glob("*.yaml"):
+        analysis = analyze_yaml_file(yaml_file)
+
+        # Track if any file uses extend/remove
+        if analysis["has_extend_remove"]:
+            has_extend_remove = True
+
+        # Track if any file defines buses directly
+        if analysis["has_direct_bus_config"]:
+            has_direct_bus_config = True
+
+        # For test.*.yaml files, extract platform and buses
+        if yaml_file.name.startswith("test.") and yaml_file.suffix == ".yaml":
+            # Extract platform name (e.g., test.esp32-ard.yaml -> esp32-ard)
+            platform = yaml_file.stem.replace("test.", "")
+            # Always add platform, even if it has no buses (empty list)
+            # This allows grouping components that don't use any shared buses
+            platform_buses[platform] = (
+                sorted(analysis["buses"]) if analysis["buses"] else []
+            )
+
+    return platform_buses, has_extend_remove, has_direct_bus_config
+
+
+def analyze_all_components(
+    tests_dir: Path = None,
+) -> tuple[dict[str, dict[str, list[str]]], set[str], set[str]]:
+    """Analyze all component test directories.
+
+    Args:
+        tests_dir: Path to tests/components directory (defaults to auto-detect)
+
+    Returns:
+        Tuple of:
+        - Dictionary mapping component name to platform->buses mapping
+        - Set of component names that cannot be grouped
+        - Set of component names that define buses directly (need migration warning)
+    """
+    if tests_dir is None:
+        tests_dir = Path("tests/components")
+
+    if not tests_dir.exists():
+        print(f"Error: {tests_dir} does not exist", file=sys.stderr)
+        return {}, set(), set()
+
+    components = {}
+    non_groupable = set()
+    direct_bus_components = set()
+
+    for component_dir in sorted(tests_dir.iterdir()):
+        if not component_dir.is_dir():
+            continue
+
+        component_name = component_dir.name
+        platform_buses, has_extend_remove, has_direct_bus_config = analyze_component(
+            component_dir
+        )
+
+        if platform_buses:
+            components[component_name] = platform_buses
+
+        # Note: Components using $component_dir are now groupable because the merge
+        # script rewrites these to absolute paths with component-specific substitutions
+
+        # Check if component is explicitly isolated
+        # These have known issues that prevent grouping with other components
+        if component_name in ISOLATED_COMPONENTS:
+            non_groupable.add(component_name)
+
+        # Check if component is a base bus component
+        # These ARE the bus platform implementations and define buses directly for testing
+        # They cannot be grouped with components that use bus packages (causes ID conflicts)
+        if component_name in BASE_BUS_COMPONENTS:
+            non_groupable.add(component_name)
+
+        # Check if component uses !extend or !remove directives
+        # These rely on specific config structure and cannot be merged with other components
+        # The directives work within a component's own package hierarchy but break when
+        # merging independent components together
+        if has_extend_remove:
+            non_groupable.add(component_name)
+
+        # Check if component defines buses directly in test files
+        # These create unique bus IDs and cause conflicts when merged
+        # Exclude base bus components (i2c, spi, uart, etc.) since they ARE the platform
+        if has_direct_bus_config and component_name not in BASE_BUS_COMPONENTS:
+            non_groupable.add(component_name)
+            direct_bus_components.add(component_name)
+
+    return components, non_groupable, direct_bus_components
+
+
+def create_grouping_signature(
+    platform_buses: dict[str, list[str]], platform: str
+) -> str:
+    """Create a signature string for grouping components.
+
+    Components with the same signature can be grouped together for testing.
+    All valid bus types can be grouped since --testing-mode bypasses runtime
+    conflicts during config validation.
+
+    Args:
+        platform_buses: Mapping of platform to list of buses
+        platform: The specific platform to create signature for
+
+    Returns:
+        Signature string (e.g., "i2c" or "uart") or empty if no valid buses
+    """
+    buses = platform_buses.get(platform, [])
+    if not buses:
+        return ""
+
+    # Only include valid bus types in signature
+    common_buses = get_common_bus_packages()
+    valid_buses = [b for b in buses if b in common_buses]
+    if not valid_buses:
+        return ""
+
+    return "+".join(sorted(valid_buses))
+
+
+def group_components_by_signature(
+    components: dict[str, dict[str, list[str]]], platform: str
+) -> dict[str, list[str]]:
+    """Group components by their bus signature for a specific platform.
+
+    Args:
+        components: Component analysis results from analyze_all_components()
+        platform: Platform to group for (e.g., "esp32-ard")
+
+    Returns:
+        Dictionary mapping signature to list of component names
+        Example: {"i2c+uart_19200": ["comp1", "comp2"], "spi": ["comp3"]}
+    """
+    signature_groups: dict[str, list[str]] = {}
+
+    for component_name, platform_buses in components.items():
+        if platform not in platform_buses:
+            continue
+
+        signature = create_grouping_signature(platform_buses, platform)
+        if not signature:
+            continue
+
+        if signature not in signature_groups:
+            signature_groups[signature] = []
+        signature_groups[signature].append(component_name)
+
+    return signature_groups
+
+
+def main() -> None:
+    """Main entry point."""
+    parser = argparse.ArgumentParser(
+        description="Analyze component test files to detect common bus usage"
+    )
+    parser.add_argument(
+        "--components",
+        "-c",
+        nargs="+",
+        help="Specific components to analyze (default: all)",
+    )
+    parser.add_argument(
+        "--platform",
+        "-p",
+        help="Show grouping for a specific platform",
+    )
+    parser.add_argument(
+        "--json",
+        action="store_true",
+        help="Output as JSON",
+    )
+    parser.add_argument(
+        "--group",
+        action="store_true",
+        help="Show component groupings by bus signature",
+    )
+
+    args = parser.parse_args()
+
+    # Analyze components
+    tests_dir = Path("tests/components")
+
+    if args.components:
+        # Analyze only specified components
+        components = {}
+        non_groupable = set()
+        direct_bus_components = set()
+        for comp in args.components:
+            comp_dir = tests_dir / comp
+            platform_buses, has_extend_remove, has_direct_bus_config = (
+                analyze_component(comp_dir)
+            )
+            if platform_buses:
+                components[comp] = platform_buses
+            # Note: Components using $component_dir are now groupable
+            if comp in ISOLATED_COMPONENTS:
+                non_groupable.add(comp)
+            if comp in BASE_BUS_COMPONENTS:
+                non_groupable.add(comp)
+            if has_direct_bus_config and comp not in BASE_BUS_COMPONENTS:
+                non_groupable.add(comp)
+                direct_bus_components.add(comp)
+    else:
+        # Analyze all components
+        components, non_groupable, direct_bus_components = analyze_all_components(
+            tests_dir
+        )
+
+    # Output results
+    if args.group and args.platform:
+        # Show groupings for a specific platform
+        groups = group_components_by_signature(components, args.platform)
+
+        if args.json:
+            print(json.dumps(groups, indent=2))
+        else:
+            print(f"Component groupings for {args.platform}:")
+            print()
+            for signature, comp_list in sorted(groups.items()):
+                print(f"  {signature}:")
+                for comp in sorted(comp_list):
+                    print(f"    - {comp}")
+                print()
+    elif args.json:
+        # JSON output
+        print(json.dumps(components, indent=2))
+    else:
+        # Human-readable output
+        for component, platform_buses in sorted(components.items()):
+            non_groupable_marker = (
+                " [NON-GROUPABLE]" if component in non_groupable else ""
+            )
+            print(f"{component}{non_groupable_marker}:")
+            for platform, buses in sorted(platform_buses.items()):
+                bus_str = ", ".join(buses)
+                print(f"  {platform}: {bus_str}")
+        print()
+        print(f"Total components analyzed: {len(components)}")
+        if non_groupable:
+            print(f"Non-groupable components (use local files): {len(non_groupable)}")
+            for comp in sorted(non_groupable):
+                print(f"  - {comp}")
+
+
+if __name__ == "__main__":
+    main()

script/determine-jobs.py

@@ -237,6 +237,16 @@ def main() -> None:
     result = subprocess.run(cmd, capture_output=True, text=True, check=True)
     changed_components = parse_list_components_output(result.stdout)
 
+    # Filter to only components that have test files
+    # Components without tests shouldn't generate CI test jobs
+    tests_dir = Path(root_path) / "tests" / "components"
+    changed_components_with_tests = [
+        component
+        for component in changed_components
+        if (component_test_dir := tests_dir / component).exists()
+        and any(component_test_dir.glob("test.*.yaml"))
+    ]
+
     # Build output
     output: dict[str, Any] = {
         "integration_tests": run_integration,
@@ -244,7 +254,8 @@ def main() -> None:
         "clang_format": run_clang_format,
         "python_linters": run_python_linters,
         "changed_components": changed_components,
-        "component_test_count": len(changed_components),
+        "changed_components_with_tests": changed_components_with_tests,
+        "component_test_count": len(changed_components_with_tests),
     }
 
     # Output as JSON

script/merge_component_configs.py

@@ -0,0 +1,379 @@
+#!/usr/bin/env python3
+"""Merge multiple component test configurations into a single test file.
+
+This script combines multiple component test files that use the same common bus
+configurations into a single merged test file. This allows testing multiple
+compatible components together, reducing CI build time.
+
+The merger handles:
+- Component-specific substitutions (prefixing to avoid conflicts)
+- Multiple instances of component configurations
+- Shared common bus packages (included only once)
+- Platform-specific configurations
+- Uses ESPHome's built-in merge_config for proper YAML merging
+"""
+
+from __future__ import annotations
+
+import argparse
+from pathlib import Path
+import re
+import sys
+from typing import Any
+
+# Add esphome to path so we can import from it
+sys.path.insert(0, str(Path(__file__).parent.parent))
+
+from esphome import yaml_util
+from esphome.config_helpers import merge_config
+from script.analyze_component_buses import PACKAGE_DEPENDENCIES, get_common_bus_packages
+
+
+def load_yaml_file(yaml_file: Path) -> dict:
+    """Load YAML file using ESPHome's YAML loader.
+
+    Args:
+        yaml_file: Path to the YAML file
+
+    Returns:
+        Parsed YAML as dictionary
+    """
+    if not yaml_file.exists():
+        raise FileNotFoundError(f"YAML file not found: {yaml_file}")
+
+    return yaml_util.load_yaml(yaml_file)
+
+
+def extract_packages_from_yaml(data: dict) -> dict[str, str]:
+    """Extract COMMON BUS package includes from parsed YAML.
+
+    Only extracts packages that are from test_build_components/common/,
+    ignoring component-specific packages.
+
+    Args:
+        data: Parsed YAML dictionary
+
+    Returns:
+        Dictionary mapping package name to include path (as string representation)
+        Only includes common bus packages (i2c, spi, uart, etc.)
+    """
+    if "packages" not in data:
+        return {}
+
+    packages_value = data["packages"]
+    if not isinstance(packages_value, dict):
+        # List format doesn't include common bus packages (those use dict format)
+        return {}
+
+    # Get common bus package names (cached)
+    common_bus_packages = get_common_bus_packages()
+    packages = {}
+
+    # Dictionary format: packages: {name: value}
+    for name, value in packages_value.items():
+        # Only include common bus packages, ignore component-specific ones
+        if name not in common_bus_packages:
+            continue
+        packages[name] = str(value)
+        # Also track package dependencies (e.g., modbus includes uart)
+        if name not in PACKAGE_DEPENDENCIES:
+            continue
+        for dep in PACKAGE_DEPENDENCIES[name]:
+            if dep not in common_bus_packages:
+                continue
+            # Mark as included via dependency
+            packages[f"_dep_{dep}"] = f"(included via {name})"
+
+    return packages
+
+
+def prefix_substitutions_in_dict(
+    data: Any, prefix: str, exclude: set[str] | None = None
+) -> Any:
+    """Recursively prefix all substitution references in a data structure.
+
+    Args:
+        data: YAML data structure (dict, list, or scalar)
+        prefix: Prefix to add to substitution names
+        exclude: Set of substitution names to exclude from prefixing
+
+    Returns:
+        Data structure with prefixed substitution references
+    """
+    if exclude is None:
+        exclude = set()
+
+    def replace_sub(text: str) -> str:
+        """Replace substitution references in a string."""
+
+        def replace_match(match):
+            sub_name = match.group(1)
+            if sub_name in exclude:
+                return match.group(0)
+            # Always use braced format in output for consistency
+            return f"${{{prefix}_{sub_name}}}"
+
+        # Match both ${substitution} and $substitution formats
+        return re.sub(r"\$\{?(\w+)\}?", replace_match, text)
+
+    if isinstance(data, dict):
+        result = {}
+        for key, value in data.items():
+            result[key] = prefix_substitutions_in_dict(value, prefix, exclude)
+        return result
+    if isinstance(data, list):
+        return [prefix_substitutions_in_dict(item, prefix, exclude) for item in data]
+    if isinstance(data, str):
+        return replace_sub(data)
+    return data
+
+
+def deduplicate_by_id(data: dict) -> dict:
+    """Deduplicate list items with the same ID.
+
+    Keeps only the first occurrence of each ID. If items with the same ID
+    are identical, this silently deduplicates. If they differ, the first
+    one is kept (ESPHome's validation will catch if this causes issues).
+
+    Args:
+        data: Parsed config dictionary
+
+    Returns:
+        Config with deduplicated lists
+    """
+    if not isinstance(data, dict):
+        return data
+
+    result = {}
+    for key, value in data.items():
+        if isinstance(value, list):
+            # Check for items with 'id' field
+            seen_ids = set()
+            deduped_list = []
+
+            for item in value:
+                if isinstance(item, dict) and "id" in item:
+                    item_id = item["id"]
+                    if item_id not in seen_ids:
+                        seen_ids.add(item_id)
+                        deduped_list.append(item)
+                    # else: skip duplicate ID (keep first occurrence)
+                else:
+                    # No ID, just add it
+                    deduped_list.append(item)
+
+            result[key] = deduped_list
+        elif isinstance(value, dict):
+            # Recursively deduplicate nested dicts
+            result[key] = deduplicate_by_id(value)
+        else:
+            result[key] = value
+
+    return result
+
+
+def merge_component_configs(
+    component_names: list[str],
+    platform: str,
+    tests_dir: Path,
+    output_file: Path,
+) -> None:
+    """Merge multiple component test configs into a single file.
+
+    Args:
+        component_names: List of component names to merge
+        platform: Platform to merge for (e.g., "esp32-ard")
+        tests_dir: Path to tests/components directory
+        output_file: Path to output merged config file
+    """
+    if not component_names:
+        raise ValueError("No components specified")
+
+    # Track packages to ensure they're identical
+    all_packages = None
+
+    # Start with empty config
+    merged_config_data = {}
+
+    # Process each component
+    for comp_name in component_names:
+        comp_dir = tests_dir / comp_name
+        test_file = comp_dir / f"test.{platform}.yaml"
+
+        if not test_file.exists():
+            raise FileNotFoundError(f"Test file not found: {test_file}")
+
+        # Load the component's test file
+        comp_data = load_yaml_file(test_file)
+
+        # Validate packages are compatible
+        # Components with no packages (no_buses) can merge with any group
+        comp_packages = extract_packages_from_yaml(comp_data)
+
+        if all_packages is None:
+            # First component - set the baseline
+            all_packages = comp_packages
+        elif not comp_packages:
+            # This component has no packages (no_buses) - it can merge with any group
+            pass
+        elif not all_packages:
+            # Previous components had no packages, but this one does - adopt these packages
+            all_packages = comp_packages
+        elif comp_packages != all_packages:
+            # Both have packages but they differ - this is an error
+            raise ValueError(
+                f"Component {comp_name} has different packages than previous components. "
+                f"Expected: {all_packages}, Got: {comp_packages}. "
+                f"All components must use the same common bus configs to be merged."
+            )
+
+        # Handle $component_dir by replacing with absolute path
+        # This allows components that use local file references to be grouped
+        comp_abs_dir = str(comp_dir.absolute())
+
+        # Save top-level substitutions BEFORE expanding packages
+        # In ESPHome, top-level substitutions override package substitutions
+        top_level_subs = (
+            comp_data["substitutions"].copy()
+            if "substitutions" in comp_data and comp_data["substitutions"] is not None
+            else {}
+        )
+
+        # Expand packages - but we'll restore substitution priority after
+        if "packages" in comp_data:
+            packages_value = comp_data["packages"]
+
+            if isinstance(packages_value, dict):
+                # Dict format - check each package
+                common_bus_packages = get_common_bus_packages()
+                for pkg_name, pkg_value in list(packages_value.items()):
+                    if pkg_name in common_bus_packages:
+                        continue
+                    if not isinstance(pkg_value, dict):
+                        continue
+                    # Component-specific package - expand its content into top level
+                    comp_data = merge_config(comp_data, pkg_value)
+            elif isinstance(packages_value, list):
+                # List format - expand all package includes
+                for pkg_value in packages_value:
+                    if not isinstance(pkg_value, dict):
+                        continue
+                    comp_data = merge_config(comp_data, pkg_value)
+
+            # Remove all packages (common will be re-added at the end)
+            del comp_data["packages"]
+
+        # Restore top-level substitution priority
+        # Top-level substitutions override any from packages
+        if "substitutions" not in comp_data or comp_data["substitutions"] is None:
+            comp_data["substitutions"] = {}
+
+        # Merge: package subs as base, top-level subs override
+        comp_data["substitutions"].update(top_level_subs)
+
+        # Now prefix the final merged substitutions
+        comp_data["substitutions"] = {
+            f"{comp_name}_{sub_name}": sub_value
+            for sub_name, sub_value in comp_data["substitutions"].items()
+        }
+
+        # Add component_dir substitution with absolute path for this component
+        comp_data["substitutions"][f"{comp_name}_component_dir"] = comp_abs_dir
+
+        # Prefix substitution references throughout the config
+        comp_data = prefix_substitutions_in_dict(comp_data, comp_name)
+
+        # Use ESPHome's merge_config to merge this component into the result
+        # merge_config handles list merging with ID-based deduplication automatically
+        merged_config_data = merge_config(merged_config_data, comp_data)
+
+    # Add packages back (only once, since they're identical)
+    # IMPORTANT: Only re-add common bus packages (spi, i2c, uart, etc.)
+    # Do NOT re-add component-specific packages as they contain unprefixed $component_dir refs
+    if all_packages:
+        first_comp_data = load_yaml_file(
+            tests_dir / component_names[0] / f"test.{platform}.yaml"
+        )
+        if "packages" in first_comp_data and isinstance(
+            first_comp_data["packages"], dict
+        ):
+            # Filter to only include common bus packages
+            # Only dict format can contain common bus packages
+            common_bus_packages = get_common_bus_packages()
+            filtered_packages = {
+                name: value
+                for name, value in first_comp_data["packages"].items()
+                if name in common_bus_packages
+            }
+            if filtered_packages:
+                merged_config_data["packages"] = filtered_packages
+
+    # Deduplicate items with same ID (keeps first occurrence)
+    merged_config_data = deduplicate_by_id(merged_config_data)
+
+    # Remove esphome section since it will be provided by the wrapper file
+    # The wrapper file includes this merged config via packages and provides
+    # the proper esphome: section with name, platform, etc.
+    if "esphome" in merged_config_data:
+        del merged_config_data["esphome"]
+
+    # Write merged config
+    output_file.parent.mkdir(parents=True, exist_ok=True)
+    yaml_content = yaml_util.dump(merged_config_data)
+    output_file.write_text(yaml_content)
+
+    print(f"Successfully merged {len(component_names)} components into {output_file}")
+
+
+def main() -> None:
+    """Main entry point."""
+    parser = argparse.ArgumentParser(
+        description="Merge multiple component test configs into a single file"
+    )
+    parser.add_argument(
+        "--components",
+        "-c",
+        required=True,
+        help="Comma-separated list of component names to merge",
+    )
+    parser.add_argument(
+        "--platform",
+        "-p",
+        required=True,
+        help="Platform to merge for (e.g., esp32-ard)",
+    )
+    parser.add_argument(
+        "--output",
+        "-o",
+        required=True,
+        type=Path,
+        help="Output file path for merged config",
+    )
+    parser.add_argument(
+        "--tests-dir",
+        type=Path,
+        default=Path("tests/components"),
+        help="Path to tests/components directory",
+    )
+
+    args = parser.parse_args()
+
+    component_names = [c.strip() for c in args.components.split(",")]
+
+    try:
+        merge_component_configs(
+            component_names=component_names,
+            platform=args.platform,
+            tests_dir=args.tests_dir,
+            output_file=args.output,
+        )
+    except Exception as e:
+        print(f"Error merging configs: {e}", file=sys.stderr)
+        import traceback
+
+        traceback.print_exc()
+        sys.exit(1)
+
+
+if __name__ == "__main__":
+    main()

script/split_components_for_ci.py

@@ -0,0 +1,268 @@
+#!/usr/bin/env python3
+"""Split components into batches with intelligent grouping.
+
+This script analyzes components to identify which ones share common bus configurations
+and intelligently groups them into batches to maximize the efficiency of the
+component grouping system in CI.
+
+Components with the same bus signature are placed in the same batch whenever possible,
+allowing the test_build_components.py script to merge them into single builds.
+"""
+
+from __future__ import annotations
+
+import argparse
+from collections import defaultdict
+import json
+from pathlib import Path
+import sys
+
+# Add esphome to path
+sys.path.insert(0, str(Path(__file__).parent.parent))
+
+from script.analyze_component_buses import (
+    ISOLATED_COMPONENTS,
+    NO_BUSES_SIGNATURE,
+    analyze_all_components,
+    create_grouping_signature,
+)
+
+# Weighting for batch creation
+# Isolated components can't be grouped/merged, so they count as 10x
+# Groupable components can be merged into single builds, so they count as 1x
+ISOLATED_WEIGHT = 10
+GROUPABLE_WEIGHT = 1
+
+
+def has_test_files(component_name: str, tests_dir: Path) -> bool:
+    """Check if a component has test files.
+
+    Args:
+        component_name: Name of the component
+        tests_dir: Path to tests/components directory
+
+    Returns:
+        True if the component has test.*.yaml files
+    """
+    component_dir = tests_dir / component_name
+    if not component_dir.exists() or not component_dir.is_dir():
+        return False
+
+    # Check for test.*.yaml files
+    return any(component_dir.glob("test.*.yaml"))
+
+
+def create_intelligent_batches(
+    components: list[str],
+    tests_dir: Path,
+    batch_size: int = 40,
+) -> list[list[str]]:
+    """Create batches optimized for component grouping.
+
+    Args:
+        components: List of component names to batch
+        tests_dir: Path to tests/components directory
+        batch_size: Target size for each batch
+
+    Returns:
+        List of component batches (lists of component names)
+    """
+    # Filter out components without test files
+    # Platform components like 'climate' and 'climate_ir' don't have test files
+    components_with_tests = [
+        comp for comp in components if has_test_files(comp, tests_dir)
+    ]
+
+    # Log filtered components to stderr for debugging
+    if len(components_with_tests) < len(components):
+        filtered_out = set(components) - set(components_with_tests)
+        print(
+            f"Note: Filtered {len(filtered_out)} components without test files: "
+            f"{', '.join(sorted(filtered_out))}",
+            file=sys.stderr,
+        )
+
+    # Analyze all components to get their bus signatures
+    component_buses, non_groupable, _direct_bus_components = analyze_all_components(
+        tests_dir
+    )
+
+    # Group components by their bus signature ONLY (ignore platform)
+    # All platforms will be tested by test_build_components.py for each batch
+    # Key: signature, Value: list of components
+    signature_groups: dict[str, list[str]] = defaultdict(list)
+
+    for component in components_with_tests:
+        # Components that can't be grouped get unique signatures
+        # This includes both manually curated ISOLATED_COMPONENTS and
+        # automatically detected non_groupable components
+        # These can share a batch/runner but won't be grouped/merged
+        if component in ISOLATED_COMPONENTS or component in non_groupable:
+            signature_groups[f"isolated_{component}"].append(component)
+            continue
+
+        # Get signature from any platform (they should all have the same buses)
+        # Components not in component_buses were filtered out by has_test_files check
+        comp_platforms = component_buses[component]
+        for platform, buses in comp_platforms.items():
+            if buses:
+                signature = create_grouping_signature({platform: buses}, platform)
+                # Group by signature only - platform doesn't matter for batching
+                signature_groups[signature].append(component)
+                break  # Only use first platform for grouping
+        else:
+            # No buses found for any platform - can be grouped together
+            signature_groups[NO_BUSES_SIGNATURE].append(component)
+
+    # Create batches by keeping signature groups together
+    # Components with the same signature stay in the same batches
+    batches = []
+
+    # Sort signature groups to prioritize groupable components
+    # 1. Put "isolated_*" signatures last (can't be grouped with others)
+    # 2. Sort groupable signatures by size (largest first)
+    # 3. "no_buses" components CAN be grouped together
+    def sort_key(item):
+        signature, components = item
+        is_isolated = signature.startswith("isolated_")
+        # Put "isolated_*" last (1), groupable first (0)
+        # Within each category, sort by size (largest first)
+        return (is_isolated, -len(components))
+
+    sorted_groups = sorted(signature_groups.items(), key=sort_key)
+
+    # Strategy: Create batches using weighted sizes
+    # - Isolated components count as 10x (since they can't be grouped/merged)
+    # - Groupable components count as 1x (can be merged into single builds)
+    # - This distributes isolated components across more runners
+    # - Ensures each runner has a good mix of groupable vs isolated components
+
+    current_batch = []
+    current_weight = 0
+
+    for signature, group_components in sorted_groups:
+        is_isolated = signature.startswith("isolated_")
+        weight_per_component = ISOLATED_WEIGHT if is_isolated else GROUPABLE_WEIGHT
+
+        for component in group_components:
+            # Check if adding this component would exceed the batch size
+            if current_weight + weight_per_component > batch_size and current_batch:
+                # Start a new batch
+                batches.append(current_batch)
+                current_batch = []
+                current_weight = 0
+
+            # Add component to current batch
+            current_batch.append(component)
+            current_weight += weight_per_component
+
+    # Don't forget the last batch
+    if current_batch:
+        batches.append(current_batch)
+
+    return batches
+
+
+def main() -> int:
+    """Main entry point."""
+    parser = argparse.ArgumentParser(
+        description="Split components into intelligent batches for CI testing"
+    )
+    parser.add_argument(
+        "--components",
+        "-c",
+        required=True,
+        help="JSON array of component names",
+    )
+    parser.add_argument(
+        "--batch-size",
+        "-b",
+        type=int,
+        default=40,
+        help="Target batch size (default: 40, weighted)",
+    )
+    parser.add_argument(
+        "--tests-dir",
+        type=Path,
+        default=Path("tests/components"),
+        help="Path to tests/components directory",
+    )
+    parser.add_argument(
+        "--output",
+        "-o",
+        choices=["json", "github"],
+        default="github",
+        help="Output format (json or github for GitHub Actions)",
+    )
+
+    args = parser.parse_args()
+
+    # Parse component list from JSON
+    try:
+        components = json.loads(args.components)
+    except json.JSONDecodeError as e:
+        print(f"Error parsing components JSON: {e}", file=sys.stderr)
+        return 1
+
+    if not isinstance(components, list):
+        print("Components must be a JSON array", file=sys.stderr)
+        return 1
+
+    # Create intelligent batches
+    batches = create_intelligent_batches(
+        components=components,
+        tests_dir=args.tests_dir,
+        batch_size=args.batch_size,
+    )
+
+    # Convert batches to space-separated strings for CI
+    batch_strings = [" ".join(batch) for batch in batches]
+
+    if args.output == "json":
+        # Output as JSON array
+        print(json.dumps(batch_strings))
+    else:
+        # Output for GitHub Actions (set output)
+        output_json = json.dumps(batch_strings)
+        print(f"components={output_json}")
+
+    # Print summary to stderr so it shows in CI logs
+    # Count actual components being batched
+    actual_components = sum(len(batch.split()) for batch in batch_strings)
+
+    # Re-analyze to get isolated component counts for summary
+    _, non_groupable, _ = analyze_all_components(args.tests_dir)
+
+    # Count isolated vs groupable components
+    all_batched_components = [comp for batch in batches for comp in batch]
+    isolated_count = sum(
+        1
+        for comp in all_batched_components
+        if comp in ISOLATED_COMPONENTS or comp in non_groupable
+    )
+    groupable_count = actual_components - isolated_count
+
+    print("\n=== Intelligent Batch Summary ===", file=sys.stderr)
+    print(f"Total components requested: {len(components)}", file=sys.stderr)
+    print(f"Components with test files: {actual_components}", file=sys.stderr)
+    print(f"  - Groupable (weight=1): {groupable_count}", file=sys.stderr)
+    print(f"  - Isolated (weight=10): {isolated_count}", file=sys.stderr)
+    if actual_components < len(components):
+        print(
+            f"Components skipped (no test files): {len(components) - actual_components}",
+            file=sys.stderr,
+        )
+    print(f"Number of batches: {len(batches)}", file=sys.stderr)
+    print(f"Batch size target (weighted): {args.batch_size}", file=sys.stderr)
+    if len(batches) > 0:
+        print(
+            f"Average components per batch: {actual_components / len(batches):.1f}",
+            file=sys.stderr,
+        )
+    print(file=sys.stderr)
+
+    return 0
+
+
+if __name__ == "__main__":
+    sys.exit(main())

script/test_build_components

@@ -1,106 +0,0 @@
-#!/usr/bin/env bash
-
-set -e
-
-help() {
-  echo "Usage: $0 [-e <config|compile|clean>] [-c <string>] [-t <string>]" 1>&2
-  echo 1>&2
-  echo "  - e - Parameter for esphome command. Default compile. Common alternative is config." 1>&2
-  echo "  - c - Component folder name to test. Default *. E.g. '-c logger'." 1>&2
-  echo "  - t - Target name to test. Put '-t list' to display all possibilities. E.g. '-t esp32-s2-idf-51'." 1>&2
-  exit 1
-}
-
-# Parse parameter:
-# - `e` - Parameter for `esphome` command. Default `compile`. Common alternative is `config`.
-# - `c` - Component folder name to test. Default `*`.
-esphome_command="compile"
-target_component="*"
-while getopts e:c:t: flag
-do
-    case $flag in
-        e) esphome_command=${OPTARG};;
-        c) target_component=${OPTARG};;
-        t) requested_target_platform=${OPTARG};;
-        \?) help;;
-    esac
-done
-
-cd "$(dirname "$0")/.."
-
-if ! [ -d "./tests/test_build_components/build" ]; then
-  mkdir ./tests/test_build_components/build
-fi
-
-start_esphome() {
-  if [ -n "$requested_target_platform" ] && [ "$requested_target_platform" != "$target_platform_with_version" ]; then
-    echo "Skipping $target_platform_with_version"
-    return
-  fi
-  # create dynamic yaml file in `build` folder.
-  # `./tests/test_build_components/build/[target_component].[test_name].[target_platform_with_version].yaml`
-  component_test_file="./tests/test_build_components/build/$target_component.$test_name.$target_platform_with_version.yaml"
-
-  cp $target_platform_file $component_test_file
-  if [[ "$OSTYPE" == "darwin"* ]]; then
-    # macOS sed is...different
-    sed -i '' "s!\$component_test_file!../../.$f!g" $component_test_file
-  else
-    sed -i "s!\$component_test_file!../../.$f!g" $component_test_file
-  fi
-
-  # Start esphome process
-  echo "> [$target_component] [$test_name] [$target_platform_with_version]"
-  set -x
-  # TODO: Validate escape of Command line substitution value
-  python3 -m esphome -s component_name $target_component -s component_dir ../../components/$target_component -s test_name $test_name -s target_platform $target_platform $esphome_command $component_test_file
-  { set +x; } 2>/dev/null
-}
-
-# Find all test yaml files.
-# - `./tests/components/[target_component]/[test_name].[target_platform].yaml`
-# - `./tests/components/[target_component]/[test_name].all.yaml`
-for f in ./tests/components/$target_component/*.*.yaml; do
-  [ -f "$f" ] || continue
-  IFS='/' read -r -a folder_name <<< "$f"
-  target_component="${folder_name[3]}"
-
-  IFS='.' read -r -a file_name <<< "${folder_name[4]}"
-  test_name="${file_name[0]}"
-  target_platform="${file_name[1]}"
-  file_name_parts=${#file_name[@]}
-
-  if [ "$target_platform" = "all" ] || [ $file_name_parts = 2 ]; then
-    # Test has *not* defined a specific target platform. Need to run tests for all possible target platforms.
-
-    for target_platform_file in ./tests/test_build_components/build_components_base.*.yaml; do
-      IFS='/' read -r -a folder_name <<< "$target_platform_file"
-      IFS='.' read -r -a file_name <<< "${folder_name[3]}"
-      target_platform="${file_name[1]}"
-
-      start_esphome
-    done
-
-  else
-    # Test has defined a specific target platform.
-
-    # Validate we have a base test yaml for selected platform.
-    # The target_platform is sourced from the following location.
-    # 1. `./tests/test_build_components/build_components_base.[target_platform].yaml`
-    # 2. `./tests/test_build_components/build_components_base.[target_platform]-ard.yaml`
-    target_platform_file="./tests/test_build_components/build_components_base.$target_platform.yaml"
-    if ! [ -f "$target_platform_file" ]; then
-      echo "No base test file [./tests/test_build_components/build_components_base.$target_platform.yaml] for component test [$f] found."
-      exit 1
-    fi
-
-    for target_platform_file in ./tests/test_build_components/build_components_base.$target_platform*.yaml; do
-      # trim off "./tests/test_build_components/build_components_base." prefix
-      target_platform_with_version=${target_platform_file:52}
-      # ...now remove suffix starting with "." leaving just the test target hardware and software platform (possibly with version)
-      # For example: "esp32-s3-idf-50"
-      target_platform_with_version=${target_platform_with_version%.*}
-      start_esphome
-    done
-  fi
-done

script/test_build_components

@@ -0,0 +1 @@
+test_build_components.py