Automatically disable interrupts for ESP8266 GPIO16 binary sensors (#9467)

esphome/components/gpio/binary_sensor/__init__.py

@@ -1,11 +1,16 @@
+import logging
+
 from esphome import pins
 import esphome.codegen as cg
 from esphome.components import binary_sensor
 import esphome.config_validation as cv
-from esphome.const import CONF_PIN
+from esphome.const import CONF_ID, CONF_NAME, CONF_NUMBER, CONF_PIN
+from esphome.core import CORE
 
 from .. import gpio_ns
 
+_LOGGER = logging.getLogger(__name__)
+
 GPIOBinarySensor = gpio_ns.class_(
     "GPIOBinarySensor", binary_sensor.BinarySensor, cg.Component
 )
@@ -41,6 +46,22 @@ async def to_code(config):
     pin = await cg.gpio_pin_expression(config[CONF_PIN])
     cg.add(var.set_pin(pin))
 
-    cg.add(var.set_use_interrupt(config[CONF_USE_INTERRUPT]))
-    if config[CONF_USE_INTERRUPT]:
+    # Check for ESP8266 GPIO16 interrupt limitation
+    # GPIO16 on ESP8266 is a special pin that doesn't support interrupts through
+    # the Arduino attachInterrupt() function. This is the only known GPIO pin
+    # across all supported platforms that has this limitation, so we handle it
+    # here instead of in the platform-specific code.
+    use_interrupt = config[CONF_USE_INTERRUPT]
+    if use_interrupt and CORE.is_esp8266 and config[CONF_PIN][CONF_NUMBER] == 16:
+        _LOGGER.warning(
+            "GPIO binary_sensor '%s': GPIO16 on ESP8266 doesn't support interrupts. "
+            "Falling back to polling mode (same as in ESPHome <2025.7). "
+            "The sensor will work exactly as before, but other pins have better "
+            "performance with interrupts.",
+            config.get(CONF_NAME, config[CONF_ID]),
+        )
+        use_interrupt = False
+
+    cg.add(var.set_use_interrupt(use_interrupt))
+    if use_interrupt:
         cg.add(var.set_interrupt_type(config[CONF_INTERRUPT_TYPE]))

tests/component_tests/gpio/test_gpio_binary_sensor.py

@@ -0,0 +1,69 @@
+"""Tests for the GPIO binary sensor component."""
+
+from __future__ import annotations
+
+from collections.abc import Callable
+from pathlib import Path
+
+import pytest
+
+
+def test_gpio_binary_sensor_basic_setup(
+    generate_main: Callable[[str | Path], str],
+) -> None:
+    """
+    When the GPIO binary sensor is set in the yaml file, it should be registered in main
+    """
+    main_cpp = generate_main("tests/component_tests/gpio/test_gpio_binary_sensor.yaml")
+
+    assert "new gpio::GPIOBinarySensor();" in main_cpp
+    assert "App.register_binary_sensor" in main_cpp
+    assert "bs_gpio->set_use_interrupt(true);" in main_cpp
+    assert "bs_gpio->set_interrupt_type(gpio::INTERRUPT_ANY_EDGE);" in main_cpp
+
+
+def test_gpio_binary_sensor_esp8266_gpio16_disables_interrupt(
+    generate_main: Callable[[str | Path], str],
+    caplog: pytest.LogCaptureFixture,
+) -> None:
+    """
+    Test that ESP8266 GPIO16 automatically disables interrupt mode with a warning
+    """
+    main_cpp = generate_main(
+        "tests/component_tests/gpio/test_gpio_binary_sensor_esp8266.yaml"
+    )
+
+    # Check that interrupt is disabled for GPIO16
+    assert "bs_gpio16->set_use_interrupt(false);" in main_cpp
+
+    # Check that the warning was logged
+    assert "GPIO16 on ESP8266 doesn't support interrupts" in caplog.text
+    assert "Falling back to polling mode" in caplog.text
+
+
+def test_gpio_binary_sensor_esp8266_other_pins_use_interrupt(
+    generate_main: Callable[[str | Path], str],
+) -> None:
+    """
+    Test that ESP8266 pins other than GPIO16 still use interrupt mode
+    """
+    main_cpp = generate_main(
+        "tests/component_tests/gpio/test_gpio_binary_sensor_esp8266.yaml"
+    )
+
+    # GPIO5 should still use interrupts
+    assert "bs_gpio5->set_use_interrupt(true);" in main_cpp
+    assert "bs_gpio5->set_interrupt_type(gpio::INTERRUPT_ANY_EDGE);" in main_cpp
+
+
+def test_gpio_binary_sensor_explicit_polling_mode(
+    generate_main: Callable[[str | Path], str],
+) -> None:
+    """
+    Test that explicitly setting use_interrupt: false works
+    """
+    main_cpp = generate_main(
+        "tests/component_tests/gpio/test_gpio_binary_sensor_polling.yaml"
+    )
+
+    assert "bs_polling->set_use_interrupt(false);" in main_cpp

tests/component_tests/gpio/test_gpio_binary_sensor.yaml

@@ -0,0 +1,11 @@
+esphome:
+  name: test
+
+esp32:
+  board: esp32dev
+
+binary_sensor:
+  - platform: gpio
+    pin: 5
+    name: "Test GPIO Binary Sensor"
+    id: bs_gpio

tests/component_tests/gpio/test_gpio_binary_sensor_esp8266.yaml

@@ -0,0 +1,20 @@
+esphome:
+  name: test
+
+esp8266:
+  board: d1_mini
+
+binary_sensor:
+  - platform: gpio
+    pin:
+      number: 16
+      mode: INPUT_PULLDOWN_16
+    name: "GPIO16 Touch Sensor"
+    id: bs_gpio16
+
+  - platform: gpio
+    pin:
+      number: 5
+      mode: INPUT_PULLUP
+    name: "GPIO5 Button"
+    id: bs_gpio5

tests/component_tests/gpio/test_gpio_binary_sensor_polling.yaml

@@ -0,0 +1,12 @@
+esphome:
+  name: test
+
+esp32:
+  board: esp32dev
+
+binary_sensor:
+  - platform: gpio
+    pin: 5
+    name: "Polling Mode Sensor"
+    id: bs_polling
+    use_interrupt: false