Unable to use default serial GPIOs by TasmotaSerial regression from v14.5.0 with IDF 5.3.2.250120 (#23775)

CHANGELOG.md

@@ -24,6 +24,7 @@ All notable changes to this project will be documented in this file.
 ### Fixed
 - Syslog RFC5424 compliance (#23509)
 - Berry calling `setmember` with a function (#23825)
+- Unable to use default serial GPIOs by TasmotaSerial regression from v14.5.0 with IDF 5.3.2.250120 (#23775)
 
 ### Removed
 - `user-scalable=no` from HTTP HEADER (#23798)

RELEASENOTES.md

@@ -152,6 +152,7 @@ The latter links can be used for OTA upgrades too like ``OtaUrl https://ota.tasm
 
 ### Fixed
 - Syslog RFC5424 compliance [#23509](https://github.com/arendst/Tasmota/issues/23509)
+- Unable to use default serial GPIOs by TasmotaSerial regression from v14.5.0 with IDF 5.3.2.250120 [#23775](https://github.com/arendst/Tasmota/issues/23775)
 - AHT30 sensor start with null values after deep sleep [#23624](https://github.com/arendst/Tasmota/issues/23624)
 - NeoPool reset to default settings [#23734](https://github.com/arendst/Tasmota/issues/23734)
 - Berry vulnerability in JSON parsing for unicode [#23603](https://github.com/arendst/Tasmota/issues/23603)

lib/default/TasmotaSerial-3.7.0/library.json

@@ -1,6 +1,6 @@
 {
     "name": "TasmotaSerial",
-    "version": "3.6.0",
+    "version": "3.7.0",
     "keywords": [
       "serial", "io", "TasmotaSerial"
     ],

lib/default/TasmotaSerial-3.7.0/library.properties

@@ -1,5 +1,5 @@
 name=TasmotaSerial
-version=3.6.0
+version=3.7.0
 author=Theo Arends
 maintainer=Theo Arends <theo@arends.com>
 sentence=Implementation of software serial with hardware serial fallback for ESP8266 and ESP32.

lib/default/TasmotaSerial-3.7.0/src/TasmotaSerial.cpp

@@ -27,6 +27,9 @@ extern "C" {
 
 #include <TasmotaSerial.h>
 
+extern void AddLog(uint32_t loglevel, PGM_P formatP, ...);
+enum LoggingLevels {LOG_LEVEL_NONE, LOG_LEVEL_ERROR, LOG_LEVEL_INFO, LOG_LEVEL_DEBUG, LOG_LEVEL_DEBUG_MORE};
+
 #ifdef ESP8266
 
 void IRAM_ATTR callRxRead(void *self) { ((TasmotaSerial*)self)->rxRead(); };
@@ -152,17 +155,33 @@ void TasmotaSerial::setTransmitEnablePin(int tx_enable_pin) {
 
 #ifdef ESP32
 bool TasmotaSerial::freeUart(void) {
-  for (uint32_t i = SOC_UART_HP_NUM -1; i >= 0; i--) {
-    if (0 == bitRead(tasmota_serial_uart_bitmap, i)) {
-      m_uart = uart_port_t(i);
-      bitSet(tasmota_serial_uart_bitmap, m_uart);
-      return true;
+  // If users selects default serial interface keep using UART0
+  //  From cores\esp32\HardwareSerial.cpp: There is always Seria0 for UART0
+  int pin_soc_rx0 = gpioNumberToDigitalPin(SOC_RX0);
+  int pin_soc_tx0 = gpioNumberToDigitalPin(SOC_TX0);
+  if (((pin_soc_rx0 == m_rx_pin) && (pin_soc_tx0 == m_tx_pin)) ||
+      ((pin_soc_rx0 == m_tx_pin) && (pin_soc_tx0 == m_rx_pin))) {
+    m_uart = uart_port_t(0);
+    bitSet(tasmota_serial_uart_bitmap, m_uart);
+    return true;
+  } else {
+    // Find a free UART which may end up as UART0
+    for (uint32_t i = SOC_UART_HP_NUM -1; i >= 0; i--) {
+      if (0 == bitRead(tasmota_serial_uart_bitmap, i)) {
+        m_uart = uart_port_t(i);
+        bitSet(tasmota_serial_uart_bitmap, m_uart);
+        return true;
+      }
     }
   }
   return false;
 }
 
 void TasmotaSerial::Esp32Begin(void) {
+  // Workaround IDF #14787 introduced in Tasmota v14.5.0, Core 3.1.1, IDF 5.3.2.250120
+  //  which kept new Rx low instead of float
+  pinMode(m_rx_pin, INPUT_PULLUP);
+  pinMode(m_tx_pin, INPUT_PULLUP);
   TSerial->begin(m_speed, m_config, m_rx_pin, m_tx_pin, m_invert);
   // For low bit rate, below 9600, set the Full RX threshold at 10 bytes instead of the default 120
   if (m_speed <= 9600) {
@@ -251,10 +270,13 @@ bool TasmotaSerial::begin(uint32_t speed, uint32_t config) {
 #if ARDUINO_USB_MODE
         TSerial = new HardwareSerial(m_uart);
 #else
-        if (0 == m_uart) {
+        if (0 == m_uart) {         // From cores\esp32\HardwareSerial.cpp: There is always Seria0 for UART0
+/*
+          // Not needed anymore since Core 3.1.0
           Serial.flush();
           Serial.end();
           delay(10);             // Allow time to cleanup queues - if not used hangs ESP32
+*/
           TSerial = &Serial;
         } else {
           TSerial = new HardwareSerial(m_uart);