Uart detach 2.0.13 (#8629)

* detaches previous pins in setPins()

* detaches previous pins in begin()

* allows setPins() or end() before begin() - detach pins

* fixes code TAB

* setPins() shouldn't detach pin = -1

cores/esp32/HardwareSerial.cpp

@@ -133,7 +133,7 @@ void serialEventRun(void)
 #define HSERIAL_MUTEX_UNLOCK()  
 #endif
 
-HardwareSerial::HardwareSerial(int uart_nr) : 
+HardwareSerial::HardwareSerial(uint8_t uart_nr) : 
 _uart_nr(uart_nr), 
 _uart(NULL),
 _rxBufferSize(256),
@@ -147,8 +147,6 @@ _eventTask(NULL)
 #if !CONFIG_DISABLE_HAL_LOCKS
     ,_lock(NULL)
 #endif
-,_rxPin(-1) 
-,_txPin(-1)
 ,_ctsPin(-1)
 ,_rtsPin(-1)
 {
@@ -161,6 +159,14 @@ _eventTask(NULL)
         }
     }
 #endif
+    // sets UART0 (default console) RX/TX pins as already configured in boot
+    if (uart_nr == 0) {    
+        _rxPin = SOC_RX0;
+        _txPin = SOC_TX0;
+    } else {
+        _rxPin = -1;
+        _txPin = -1;
+    }
 }
 
 HardwareSerial::~HardwareSerial()
@@ -330,7 +336,7 @@ void HardwareSerial::_uartEventTask(void *args)
 
 void HardwareSerial::begin(unsigned long baud, uint32_t config, int8_t rxPin, int8_t txPin, bool invert, unsigned long timeout_ms, uint8_t rxfifo_full_thrhd)
 {
-    if(0 > _uart_nr || _uart_nr >= SOC_UART_NUM) {
+    if(_uart_nr >= SOC_UART_NUM) {
         log_e("Serial number is invalid, please use numers from 0 to %u", SOC_UART_NUM - 1);
         return;
     }
@@ -348,23 +354,26 @@ void HardwareSerial::begin(unsigned long baud, uint32_t config, int8_t rxPin, in
         switch (_uart_nr) {
             case UART_NUM_0:
                 if (rxPin < 0 && txPin < 0) {
-                    rxPin = SOC_RX0;
-                    txPin = SOC_TX0;
+                    // do not change RX0/TX0 if it has already been set before
+                    rxPin = _rxPin < 0 ? SOC_RX0 : _rxPin;
+                    txPin = _txPin < 0 ? SOC_TX0 : _txPin;
                 }
             break;
 #if SOC_UART_NUM > 1                   // may save some flash bytes...
             case UART_NUM_1:
                if (rxPin < 0 && txPin < 0) {
-                    rxPin = RX1;
-                    txPin = TX1;
+                    // do not change RX1/TX1 if it has already been set before
+                    rxPin = _rxPin < 0 ? RX1 : _rxPin;
+                    txPin = _txPin < 0 ? TX1 : _txPin;
                 }
             break;
 #endif
 #if SOC_UART_NUM > 2                   // may save some flash bytes...
             case UART_NUM_2:
                if (rxPin < 0 && txPin < 0) {
-                    rxPin = RX2;
-                    txPin = TX2;
+                    // do not change RX2/TX2 if it has already been set before
+                    rxPin = _rxPin < 0 ? RX2 : _rxPin;
+                    txPin = _txPin < 0 ? TX2 : _txPin;
                 }
             break;
 #endif
@@ -424,9 +433,17 @@ void HardwareSerial::begin(unsigned long baud, uint32_t config, int8_t rxPin, in
       uartSetRxFIFOFull(_uart, fifoFull);
       _rxFIFOFull = fifoFull;
     }
-
-    _rxPin = rxPin;
-    _txPin = txPin;
+    // detach previous attached RX/TX pins when it has changed
+    if (_uart != NULL) {
+        if (rxPin >= 0 && rxPin != _rxPin) {
+            uartDetachPins(_uart_nr, _rxPin, -1, -1, -1);
+            _rxPin = rxPin;
+        }
+        if (txPin >= 0 && txPin != _txPin) {
+            uartDetachPins(_uart_nr, -1, _txPin, -1, -1);
+            _txPin = txPin;
+        }        
+    }    
 
     HSERIAL_MUTEX_UNLOCK();
 }
@@ -449,7 +466,7 @@ void HardwareSerial::end(bool fullyTerminate)
 
         _rxFIFOFull = 0; 
 
-        uartDetachPins(_uart, _rxPin, _txPin, _ctsPin, _rtsPin);
+        uartDetachPins(_uart_nr, _rxPin, _txPin, _ctsPin, _rtsPin);
         _rxPin = _txPin = _ctsPin = _rtsPin = -1;
 
     }
@@ -554,11 +571,6 @@ void HardwareSerial::setRxInvert(bool invert)
 // negative Pin value will keep it unmodified
 bool HardwareSerial::setPins(int8_t rxPin, int8_t txPin, int8_t ctsPin, int8_t rtsPin)
 {
-    if(_uart == NULL) {
-        log_e("setPins() shall be called after begin() - nothing done\n");
-        return false;
-    }
-
     // map logical pins to GPIO numbers
     rxPin = digitalPinToGPIONumber(rxPin);
     txPin = digitalPinToGPIONumber(txPin);
@@ -566,12 +578,18 @@ bool HardwareSerial::setPins(int8_t rxPin, int8_t txPin, int8_t ctsPin, int8_t r
     rtsPin = digitalPinToGPIONumber(rtsPin);
 
     // uartSetPins() checks if pins are valid for each function and for the SoC
-    bool retCode = uartSetPins(_uart, rxPin, txPin, ctsPin, rtsPin);
+    bool retCode = uartSetPins(_uart_nr, rxPin, txPin, ctsPin, rtsPin);
     if (retCode) {
-        _txPin = _txPin >= 0 ? txPin : _txPin;
-        _rxPin = _rxPin >= 0 ? rxPin : _rxPin;
-        _rtsPin = _rtsPin >= 0 ? rtsPin : _rtsPin;
-        _ctsPin = _ctsPin >= 0 ? ctsPin : _ctsPin;
+        // detach previous attached UART pins if not set as same as before
+        if (_rxPin >= 0 && rxPin >= 0 &&_rxPin != rxPin) uartDetachPins(_uart_nr, _rxPin, -1, -1, -1);
+        if (_txPin >= 0 && txPin >= 0 && _txPin != txPin) uartDetachPins(_uart_nr, -1, _txPin, -1, -1);
+        if (_ctsPin >= 0 && ctsPin >= 0 && _ctsPin != ctsPin) uartDetachPins(_uart_nr, -1, -1, _ctsPin, -1);
+        if (_rtsPin >= 0 &&  rtsPin >= 0 &&_rtsPin != rtsPin) uartDetachPins(_uart_nr, -1, -1, -1, _rtsPin);
+        // set new pins for a future end() or a setPins()    
+        _txPin = txPin >= 0 ? txPin : _txPin;
+        _rxPin = rxPin >= 0 ? rxPin : _rxPin;
+        _rtsPin = rtsPin >= 0 ? rtsPin : _rtsPin;
+        _ctsPin = ctsPin >= 0 ? ctsPin : _ctsPin;       
     } else {
         log_e("Error when setting Serial port Pins. Invalid Pin.\n");
     }

cores/esp32/HardwareSerial.h

@@ -71,7 +71,7 @@ typedef std::function<void(hardwareSerial_error_t)> OnReceiveErrorCb;
 class HardwareSerial: public Stream
 {
 public:
-    HardwareSerial(int uart_nr);
+    HardwareSerial(uint8_t uart_nr);
     ~HardwareSerial();
 
     // setRxTimeout sets the timeout after which onReceive callback will be called (after receiving data, it waits for this time of UART rx inactivity to call the callback fnc)
@@ -170,7 +170,7 @@ public:
     size_t setTxBufferSize(size_t new_size);
 
 protected:
-    int _uart_nr;
+    uint8_t _uart_nr;
     uart_t* _uart;
     size_t _rxBufferSize;
     size_t _txBufferSize;

cores/esp32/esp32-hal-uart.c

@@ -79,13 +79,13 @@ static uart_t _uart_bus_array[] = {
 // be seen in the previous pins and new pins as well. 
 // Valid pin UART_PIN_NO_CHANGE is defined to (-1)
 // Negative Pin Number will keep it unmodified, thus this function can detach individual pins
-void uartDetachPins(uart_t* uart, int8_t rxPin, int8_t txPin, int8_t ctsPin, int8_t rtsPin)
+void uartDetachPins(uint8_t uart_num, int8_t rxPin, int8_t txPin, int8_t ctsPin, int8_t rtsPin)
 {
-    if(uart == NULL) {
+    if(uart_num >= SOC_UART_NUM) {
+        log_e("Serial number is invalid, please use numers from 0 to %u", SOC_UART_NUM - 1);
         return;
     }
 
-    UART_MUTEX_LOCK();
     if (txPin >= 0) {
         gpio_hal_iomux_func_sel(GPIO_PIN_MUX_REG[txPin], PIN_FUNC_GPIO);
         esp_rom_gpio_connect_out_signal(txPin, SIG_GPIO_OUT_IDX, false, false);
@@ -93,7 +93,7 @@ void uartDetachPins(uart_t* uart, int8_t rxPin, int8_t txPin, int8_t ctsPin, int
 
     if (rxPin >= 0) {
         gpio_hal_iomux_func_sel(GPIO_PIN_MUX_REG[rxPin], PIN_FUNC_GPIO);
-        esp_rom_gpio_connect_in_signal(GPIO_FUNC_IN_LOW, UART_PERIPH_SIGNAL(uart->num, SOC_UART_RX_PIN_IDX), false);
+        esp_rom_gpio_connect_in_signal(GPIO_FUNC_IN_LOW, UART_PERIPH_SIGNAL(uart_num, SOC_UART_RX_PIN_IDX), false);
     }
 
     if (rtsPin >= 0) {
@@ -103,9 +103,8 @@ void uartDetachPins(uart_t* uart, int8_t rxPin, int8_t txPin, int8_t ctsPin, int
 
     if (ctsPin >= 0) {
         gpio_hal_iomux_func_sel(GPIO_PIN_MUX_REG[ctsPin], PIN_FUNC_GPIO);
-        esp_rom_gpio_connect_in_signal(GPIO_FUNC_IN_LOW, UART_PERIPH_SIGNAL(uart->num, SOC_UART_CTS_PIN_IDX), false);
+        esp_rom_gpio_connect_in_signal(GPIO_FUNC_IN_LOW, UART_PERIPH_SIGNAL(uart_num, SOC_UART_CTS_PIN_IDX), false);
     }
-    UART_MUTEX_UNLOCK();  
 }
 
 // solves issue https://github.com/espressif/arduino-esp32/issues/6032
@@ -147,15 +146,15 @@ bool uartIsDriverInstalled(uart_t* uart)
 
 // Valid pin UART_PIN_NO_CHANGE is defined to (-1)
 // Negative Pin Number will keep it unmodified, thus this function can set individual pins
-bool uartSetPins(uart_t* uart, int8_t rxPin, int8_t txPin, int8_t ctsPin, int8_t rtsPin)
+bool uartSetPins(uint8_t uart_num, int8_t rxPin, int8_t txPin, int8_t ctsPin, int8_t rtsPin)
 {
-    if(uart == NULL) {
-        return false;
+    if(uart_num >= SOC_UART_NUM) {
+        log_e("Serial number is invalid, please use numers from 0 to %u", SOC_UART_NUM - 1);
+        return;
     }
-    UART_MUTEX_LOCK();
+
     // IDF uart_set_pin() will issue necessary Error Message and take care of all GPIO Number validation.
-    bool retCode = uart_set_pin(uart->num, txPin, rxPin, rtsPin, ctsPin) == ESP_OK; 
-    UART_MUTEX_UNLOCK();  
+    bool retCode = uart_set_pin(uart_num, txPin, rxPin, rtsPin, ctsPin) == ESP_OK; 
     return retCode;
 }
 

cores/esp32/esp32-hal-uart.h

@@ -131,8 +131,8 @@ int uartGetDebug();
 bool uartIsDriverInstalled(uart_t* uart);
 
 // Negative Pin Number will keep it unmodified, thus this function can set/reset individual pins
-bool uartSetPins(uart_t* uart, int8_t rxPin, int8_t txPin, int8_t ctsPin, int8_t rtsPin);
-void uartDetachPins(uart_t* uart, int8_t rxPin, int8_t txPin, int8_t ctsPin, int8_t rtsPin);
+bool uartSetPins(uint8_t uart_num, int8_t rxPin, int8_t txPin, int8_t ctsPin, int8_t rtsPin);
+void uartDetachPins(uint8_t uart_num, int8_t rxPin, int8_t txPin, int8_t ctsPin, int8_t rtsPin);
 
 // Enables or disables HW Flow Control function -- needs also to set CTS and/or RTS pins
 bool uartSetHwFlowCtrlMode(uart_t *uart, uint8_t mode, uint8_t threshold);