Enable ESP watchdog by default

Use the ESP watchdog to detect hanging ESP and reset the firmware.
Can be disable by defining WLED_WATCHDOG_TIMOUT 0
Default timeout is 3 seconds on ESP32 and 8 seconds on ESP2688

wled00/wled.cpp

@@ -276,6 +276,15 @@ void WLED::loop()
   loops++;
 #endif        // WLED_DEBUG
   toki.resetTick();
+
+#if WLED_WATCHDOG_TIMEOUT > 0
+  // we finished our mainloop, reset the watchdog timer
+  #ifdef ARDUINO_ARCH_ESP32
+    esp_task_wdt_reset();
+  #else
+    ESP.wdtFeed();
+  #endif
+#endif
 }
 
 void WLED::setup()
@@ -302,6 +311,22 @@ void WLED::setup()
   DEBUG_PRINT(F("heap "));
   DEBUG_PRINTLN(ESP.getFreeHeap());
 
+#if WLED_WATCHDOG_TIMEOUT > 0
+#ifdef ARDUINO_ARCH_ESP32
+  esp_err_t watchdog = esp_task_wdt_init(WLED_WATCHDOG_TIMEOUT, true);
+  DEBUG_PRINT(F("Enable watchdog "));
+  if (watchdog == ESP_OK) {
+    DEBUG_PRINTLN(F(" OK"));
+  } else {
+    DEBUG_PRINTLN(watchdog);
+  }
+  esp_task_wdt_add(NULL);
+#else
+  // any timeout possible ?
+  ESP.wdtEnable(WLED_WATCHDOG_TIMEOUT * 1000);
+#endif
+#endif
+
   #if defined(ARDUINO_ARCH_ESP32) && defined(WLED_USE_PSRAM)
   if (psramFound()) {
     // GPIO16/GPIO17 reserved for SPI RAM

wled00/wled.h

@@ -49,6 +49,12 @@
 // filesystem specific debugging
 //#define WLED_DEBUG_FS
 
+#ifndef WLED_WATCHDOG_TIMEOUT
+  // 3 seconds should be enough to detect a lockup
+  // define WLED_WATCHDOG_TIMEOUT=0 to disable watchdog
+  #define WLED_WATCHDOG_TIMEOUT 3
+#endif
+
 //optionally disable brownout detector on ESP32.
 //This is generally a terrible idea, but improves boot success on boards with a 3.3v regulator + cap setup that can't provide 400mA peaks
 //#define WLED_DISABLE_BROWNOUT_DET
@@ -78,6 +84,7 @@
   #else
     #include <LittleFS.h>
   #endif
+  #include "esp_task_wdt.h"
 #endif
 
 #include "src/dependencies/network/Network.h"