[UART] Reduce serial_t size

baudrate, databits, stopbits and parity are used only
during init.
So, they are no reason to save them in the structure.
This allow to save space.

Signed-off-by: Frederic.Pillon <[email protected]>

Author: fpistm

cores/arduino/HardwareSerial.cpp

@@ -244,7 +244,7 @@ void HardwareSerial::configForLowPower(void)
   // Reconfigure properly Serial instance to use HSI as clock source
   end();
   uart_config_lowpower(&_serial);
-  begin(_serial.baudrate, _config);
+  begin(_baud, _config);
 #endif
 }
 
@@ -290,8 +290,10 @@ int HardwareSerial::_tx_complete_irq(serial_t *obj)
 void HardwareSerial::begin(unsigned long baud, byte config)
 {
   uint32_t databits = 0;
+  uint32_t stopbits = 0;
+  uint32_t parity = 0;
 
-  _serial.baudrate = (uint32_t)baud;
+  _baud = baud;
   _config = config;
 
   // Manage databits
@@ -311,40 +313,40 @@ void HardwareSerial::begin(unsigned long baud, byte config)
   }
 
   if ((config & 0x30) == 0x30) {
-    _serial.parity = UART_PARITY_ODD;
+    parity = UART_PARITY_ODD;
     databits++;
   } else if ((config & 0x20) == 0x20) {
-    _serial.parity = UART_PARITY_EVEN;
+    parity = UART_PARITY_EVEN;
     databits++;
   } else {
-    _serial.parity = UART_PARITY_NONE;
+    parity = UART_PARITY_NONE;
   }
 
   if ((config & 0x08) == 0x08) {
-    _serial.stopbits = UART_STOPBITS_2;
+    stopbits = UART_STOPBITS_2;
   } else {
-    _serial.stopbits = UART_STOPBITS_1;
+    stopbits = UART_STOPBITS_1;
   }
 
   switch (databits) {
 #ifdef UART_WORDLENGTH_7B
     case 7:
-      _serial.databits = UART_WORDLENGTH_7B;
+      databits = UART_WORDLENGTH_7B;
       break;
 #endif
     case 8:
-      _serial.databits = UART_WORDLENGTH_8B;
+      databits = UART_WORDLENGTH_8B;
       break;
     case 9:
-      _serial.databits = UART_WORDLENGTH_9B;
+      databits = UART_WORDLENGTH_9B;
       break;
     default:
     case 0:
       Error_Handler();
       break;
   }
 
-  uart_init(&_serial);
+  uart_init(&_serial, (uint32_t)baud, databits, parity, stopbits);
   uart_attach_rx_callback(&_serial, _rx_complete_irq);
 }
 

cores/arduino/HardwareSerial.h

@@ -150,6 +150,7 @@ class HardwareSerial : public Stream {
     static int _tx_complete_irq(serial_t *obj);
   private:
     uint8_t _config;
+    unsigned long _baud;
     void init(void);
     void configForLowPower(void);
 };

cores/arduino/stm32/uart.c

@@ -118,7 +118,7 @@ serial_t *get_serial_obj(UART_HandleTypeDef *huart)
   * @param  obj : pointer to serial_t structure
   * @retval None
   */
-void uart_init(serial_t *obj)
+void uart_init(serial_t *obj, uint32_t baudrate, uint32_t databits, uint32_t parity, uint32_t stopbits)
 {
   if (obj == NULL) {
     return;
@@ -293,10 +293,10 @@ void uart_init(serial_t *obj)
   /* Configure uart */
   uart_handlers[obj->index] = huart;
   huart->Instance          = (USART_TypeDef *)(obj->uart);
-  huart->Init.BaudRate     = obj->baudrate;
-  huart->Init.WordLength   = obj->databits;
-  huart->Init.StopBits     = obj->stopbits;
-  huart->Init.Parity       = obj->parity;
+  huart->Init.BaudRate     = baudrate;
+  huart->Init.WordLength   = databits;
+  huart->Init.StopBits     = stopbits;
+  huart->Init.Parity       = parity;
   huart->Init.Mode         = UART_MODE_TX_RX;
   huart->Init.HwFlowCtl    = UART_HWCONTROL_NONE;
   huart->Init.OverSampling = UART_OVERSAMPLING_16;
@@ -315,7 +315,7 @@ void uart_init(serial_t *obj)
    * check Reference Manual
    */
   if (obj->uart == LPUART1) {
-    if (obj->baudrate <= 9600) {
+    if (baudrate <= 9600) {
 #if defined(USART_CR3_UCESM)
       HAL_UARTEx_EnableClockStopMode(huart);
 #endif
@@ -332,7 +332,7 @@ void uart_init(serial_t *obj)
     }
     /* Trying to change LPUART clock source */
     /* If baudrate is lower than or equal to 9600 try to change to LSE */
-    if (obj->baudrate <= 9600) {
+    if (baudrate <= 9600) {
       /* Enable the clock if not already set by user */
       enableClock(LSE_CLOCK);
 
@@ -578,12 +578,8 @@ void uart_debug_init(void)
 #else
     serial_debug.pin_tx = pinmap_pin(DEBUG_UART, PinMap_UART_TX);
 #endif
-    serial_debug.baudrate = DEBUG_UART_BAUDRATE;
-    serial_debug.parity = UART_PARITY_NONE;
-    serial_debug.databits = UART_WORDLENGTH_8B;
-    serial_debug.stopbits = UART_STOPBITS_1;
 
-    uart_init(&serial_debug);
+    uart_init(&serial_debug, DEBUG_UART_BAUDRATE, UART_WORDLENGTH_8B, UART_PARITY_NONE, UART_STOPBITS_1);
   }
 }
 

cores/arduino/stm32/uart.h

@@ -62,10 +62,6 @@ struct serial_s {
   UART_HandleTypeDef handle;
   void (*rx_callback)(serial_t *);
   int (*tx_callback)(serial_t *);
-  uint32_t baudrate;
-  uint32_t databits;
-  uint32_t stopbits;
-  uint32_t parity;
   PinName pin_tx;
   PinName pin_rx;
   IRQn_Type irq;
@@ -165,7 +161,7 @@ struct serial_s {
 
 /* Exported macro ------------------------------------------------------------*/
 /* Exported functions ------------------------------------------------------- */
-void uart_init(serial_t *obj);
+void uart_init(serial_t *obj, uint32_t baudrate, uint32_t databits, uint32_t parity, uint32_t stopbits);
 void uart_deinit(serial_t *obj);
 #if defined(HAL_PWR_MODULE_ENABLED) && defined(UART_IT_WUF)
 void uart_config_lowpower(serial_t *obj);