From 46b18ea41e0f033d02afbcc2a4562c140a766e62 Mon Sep 17 00:00:00 2001
From: Stephan Hadinger <stephan.hadinger@gmail.com>
Date: Sat, 6 Mar 2021 18:43:32 +0100
Subject: [PATCH] Fix WS2812 ESP32

---
 tasmota/xlgt_01_ws2812.ino | 107 +++++++++++++++++++++++++++++++++++++
 1 file changed, 107 insertions(+)

diff --git a/tasmota/xlgt_01_ws2812.ino b/tasmota/xlgt_01_ws2812.ino
index fcd685931..eaea82135 100644
--- a/tasmota/xlgt_01_ws2812.ino
+++ b/tasmota/xlgt_01_ws2812.ino
@@ -123,6 +123,113 @@ void (* const Ws2812Command[])(void) PROGMEM = {
 
 #endif  // No USE_WS2812_DMA
 
+#ifdef ESP32
+//
+// Below is a quick work-around to ESP32 gcc that prevents templated methods to be in IRAM unless explicitly marked per specialization
+// It will work only for the default WS2812 (800KHz) and inverted and non-inverted
+//
+template <>
+void IRAM_ATTR NeoEspBitBangBase<NeoEspSpeed800Mhz, NeoEspPinset>::send_pixels(uint8_t* pixels, uint8_t* end, uint8_t pin)
+{
+    const uint32_t pinRegister = _BV(pin);
+    uint8_t mask = 0x80;
+    uint8_t subpix = *pixels++;
+    uint32_t cyclesStart = 0; // trigger emediately
+    uint32_t cyclesNext = 0;
+
+    for (;;)
+    {
+        // do the checks here while we are waiting on time to pass
+        uint32_t cyclesBit = NeoEspSpeed800Mhz::T0H;
+        if (subpix & mask)
+        {
+            cyclesBit = NeoEspSpeed800Mhz::T1H;
+        }
+
+        // after we have done as much work as needed for this next bit
+        // now wait for the HIGH
+        while (((cyclesStart = getCycleCount()) - cyclesNext) < NeoEspSpeed800Mhz::Period);
+
+        // set pin state
+        NeoEspPinset::setPin(pinRegister);
+
+        // wait for the LOW
+        while ((getCycleCount() - cyclesStart) < cyclesBit);
+
+        // reset pin start
+        NeoEspPinset::resetPin(pinRegister);
+
+        cyclesNext = cyclesStart;
+
+        // next bit
+        mask >>= 1;
+        if (mask == 0)
+        {
+            // no more bits to send in this byte
+            // check for another byte
+            if (pixels >= end)
+            {
+                // no more bytes to send so stop
+                break;
+            }
+            // reset mask to first bit and get the next byte
+            mask = 0x80;
+            subpix = *pixels++;
+        }
+    }
+}
+template <>
+void IRAM_ATTR NeoEspBitBangBase<NeoEspSpeed800Mhz, NeoEspPinsetInverted>::send_pixels(uint8_t* pixels, uint8_t* end, uint8_t pin)
+{
+    const uint32_t pinRegister = _BV(pin);
+    uint8_t mask = 0x80;
+    uint8_t subpix = *pixels++;
+    uint32_t cyclesStart = 0; // trigger emediately
+    uint32_t cyclesNext = 0;
+
+    for (;;)
+    {
+        // do the checks here while we are waiting on time to pass
+        uint32_t cyclesBit = NeoEspSpeed800Mhz::T0H;
+        if (subpix & mask)
+        {
+            cyclesBit = NeoEspSpeed800Mhz::T1H;
+        }
+
+        // after we have done as much work as needed for this next bit
+        // now wait for the HIGH
+        while (((cyclesStart = getCycleCount()) - cyclesNext) < NeoEspSpeed800Mhz::Period);
+
+        // set pin state
+        NeoEspPinsetInverted::setPin(pinRegister);
+
+        // wait for the LOW
+        while ((getCycleCount() - cyclesStart) < cyclesBit);
+
+        // reset pin start
+        NeoEspPinsetInverted::resetPin(pinRegister);
+
+        cyclesNext = cyclesStart;
+
+        // next bit
+        mask >>= 1;
+        if (mask == 0)
+        {
+            // no more bits to send in this byte
+            // check for another byte
+            if (pixels >= end)
+            {
+                // no more bytes to send so stop
+                break;
+            }
+            // reset mask to first bit and get the next byte
+            mask = 0x80;
+            subpix = *pixels++;
+        }
+    }
+}
+#endif // ESP32
+
 NeoPixelBus<selectedNeoFeatureType, selectedNeoSpeedType> *strip = nullptr;
 
 struct WsColor {