STM32 serial: improve irq index management for L0 devices

Author: bcostm

targets/TARGET_STM/TARGET_STM32L0/serial_device.c

@@ -45,29 +45,35 @@ UART_HandleTypeDef uart_handlers[UART_NUM];
 
 static uart_irq_handler irq_handler;
 
+// Defined in serial_api.c
+inline int8_t get_uart_index(UARTName uart_name);
+
 /******************************************************************************
  * INTERRUPTS HANDLING
  ******************************************************************************/
 
-static void uart_irq(int id)
+static void uart_irq(UARTName uart_name)
 {
-    UART_HandleTypeDef * huart = &uart_handlers[id];
-    
-    if (serial_irq_ids[id] != 0) {
-        if (__HAL_UART_GET_FLAG(huart, UART_FLAG_TXE) != RESET) {
-            if (__HAL_UART_GET_IT(huart, UART_IT_TXE) != RESET) {
-                irq_handler(serial_irq_ids[id], TxIrq);
+    int8_t id = get_uart_index(uart_name);
+
+    if (id >= 0) {
+        UART_HandleTypeDef * huart = &uart_handlers[id];
+        if (serial_irq_ids[id] != 0) {
+            if (__HAL_UART_GET_FLAG(huart, UART_FLAG_TXE) != RESET) {
+                if (__HAL_UART_GET_IT(huart, UART_IT_TXE) != RESET) {
+                    irq_handler(serial_irq_ids[id], TxIrq);
+                }
             }
-        }
-        if (__HAL_UART_GET_FLAG(huart, UART_FLAG_RXNE) != RESET) {
-            if (__HAL_UART_GET_IT(huart, UART_IT_RXNE) != RESET) {
-                irq_handler(serial_irq_ids[id], RxIrq);
-                /*  Flag has been cleared when reading the content */
+            if (__HAL_UART_GET_FLAG(huart, UART_FLAG_RXNE) != RESET) {
+                if (__HAL_UART_GET_IT(huart, UART_IT_RXNE) != RESET) {
+                    irq_handler(serial_irq_ids[id], RxIrq);
+                    /* Flag has been cleared when reading the content */
+                }
             }
-        }
-        if (__HAL_UART_GET_FLAG(huart, UART_FLAG_ORE) != RESET) {
-            if (__HAL_UART_GET_IT(huart, UART_IT_ORE) != RESET) {
-                __HAL_UART_CLEAR_FLAG(huart, UART_CLEAR_OREF);
+            if (__HAL_UART_GET_FLAG(huart, UART_FLAG_ORE) != RESET) {
+                if (__HAL_UART_GET_IT(huart, UART_IT_ORE) != RESET) {
+                    __HAL_UART_CLEAR_FLAG(huart, UART_CLEAR_OREF);
+                }
             }
         }
     }
@@ -76,31 +82,35 @@ static void uart_irq(int id)
 #if defined(USART1_BASE)
 static void uart1_irq(void)
 {
-    uart_irq(0);
+    uart_irq(UART_1);
 }
 #endif
 
+#if defined(USART2_BASE)
 static void uart2_irq(void)
 {
-    uart_irq(1);
-}
-
-static void lpuart1_irq(void)
-{
-    uart_irq(2);
+    uart_irq(UART_2);
 }
+#endif
 
 #if defined(USART4_BASE)
 static void uart4_irq(void)
 {
-    uart_irq(3);
+    uart_irq(UART_4);
 }
 #endif
 
 #if defined(USART5_BASE)
 static void uart5_irq(void)
 {
-    uart_irq(4);
+    uart_irq(UART_5);
+}
+#endif
+
+#if defined(LPUART1_BASE)
+static void lpuart1_irq(void)
+{
+    uart_irq(LPUART_1);
 }
 #endif
 
@@ -126,15 +136,12 @@ void serial_irq_set(serial_t *obj, SerialIrq irq, uint32_t enable)
     }
 #endif
 
+#if defined(USART2_BASE)
     if (obj_s->uart == UART_2) {
         irq_n = USART2_IRQn;
         vector = (uint32_t)&uart2_irq;
     }
-
-    if (obj_s->uart == LPUART_1) {
-        irq_n = RNG_LPUART1_IRQn;
-        vector = (uint32_t)&lpuart1_irq;
-    }
+#endif
 
 #if defined(USART4_BASE)
     if (obj_s->uart == UART_4) {
@@ -150,6 +157,13 @@ void serial_irq_set(serial_t *obj, SerialIrq irq, uint32_t enable)
     }
 #endif
 
+#if defined(LPUART1_BASE)
+    if (obj_s->uart == LPUART_1) {
+        irq_n = RNG_LPUART1_IRQn;
+        vector = (uint32_t)&lpuart1_irq;
+    }
+#endif
+
     if (enable) {
         if (irq == RxIrq) {
             __HAL_UART_ENABLE_IT(huart, UART_IT_RXNE);
@@ -291,41 +305,43 @@ static void serial_enable_event(serial_t *obj, int event, uint8_t enable)
 /**
 * Get index of serial object TX IRQ, relating it to the physical peripheral.
 *
-* @param obj pointer to serial object
+* @param uart_name i.e. UART_1, UART_2, ...
 * @return internal NVIC TX IRQ index of U(S)ART peripheral
 */
-static IRQn_Type serial_get_irq_n(serial_t *obj)
+static IRQn_Type serial_get_irq_n(UARTName uart_name)
 {
-    struct serial_s *obj_s = SERIAL_S(obj);
     IRQn_Type irq_n;
 
-    switch (obj_s->index) {
+    switch (uart_name) {
 #if defined(USART1_BASE)
-        case 0:
+        case UART_1:
             irq_n = USART1_IRQn;
             break;
 #endif
-        case 1:
+#if defined(USART2_BASE)
+        case UART_2:
             irq_n = USART2_IRQn;
             break;
-            
-        case 2:
-            irq_n = RNG_LPUART1_IRQn;
-            break;
+#endif
 #if defined(USART4_BASE)
-        case 3:
+        case UART_4:
             irq_n = USART4_5_IRQn;
             break;
 #endif
 #if defined(USART5_BASE)
-        case 4:
+        case UART_5:
             irq_n = USART4_5_IRQn;
             break;
+#endif
+#if defined(LPUART1_BASE)
+        case LPUART_1:
+            irq_n = RNG_LPUART1_IRQn;
+            break;
 #endif
         default:
             irq_n = (IRQn_Type)0;
     }
-    
+
     return irq_n;
 }
 
@@ -371,7 +387,7 @@ int serial_tx_asynch(serial_t *obj, const void *tx, size_t tx_length, uint8_t tx
     serial_enable_event(obj, event, 1); // Set only the wanted events
 
     // Enable interrupt
-    IRQn_Type irq_n = serial_get_irq_n(obj);
+    IRQn_Type irq_n = serial_get_irq_n(obj_s->uart);
     NVIC_ClearPendingIRQ(irq_n);
     NVIC_DisableIRQ(irq_n);
     NVIC_SetPriority(irq_n, 1);
@@ -421,7 +437,7 @@ void serial_rx_asynch(serial_t *obj, void *rx, size_t rx_length, uint8_t rx_widt
 
     serial_rx_buffer_set(obj, rx, rx_length, rx_width);
 
-    IRQn_Type irq_n = serial_get_irq_n(obj);
+    IRQn_Type irq_n = serial_get_irq_n(obj_s->uart);
     NVIC_ClearPendingIRQ(irq_n);
     NVIC_DisableIRQ(irq_n);
     NVIC_SetPriority(irq_n, 0);