Fix UART error callback (clear flags and restart receive IT)

Author: ppescher

cores/arduino/stm32/uart.c

@@ -797,16 +797,23 @@ void HAL_UART_ErrorCallback(UART_HandleTypeDef *huart)
   }
 #else
   if (__HAL_UART_GET_FLAG(huart, UART_FLAG_PE) != RESET) {
-    tmpval = huart->Instance->RDR; /* Clear PE flag */
+    __HAL_UART_CLEAR_FLAG(huart, UART_CLEAR_PEF); /* Clear PE flag */
   } else if (__HAL_UART_GET_FLAG(huart, UART_FLAG_FE) != RESET) {
-    tmpval = huart->Instance->RDR; /* Clear FE flag */
+    __HAL_UART_CLEAR_FLAG(huart, UART_CLEAR_FEF); /* Clear FE flag */
   } else if (__HAL_UART_GET_FLAG(huart, UART_FLAG_NE) != RESET) {
-    tmpval = huart->Instance->RDR; /* Clear NE flag */
+    __HAL_UART_CLEAR_FLAG(huart, UART_CLEAR_NEF); /* Clear NE flag */
   } else if (__HAL_UART_GET_FLAG(huart, UART_FLAG_ORE) != RESET) {
-    tmpval = huart->Instance->RDR; /* Clear ORE flag */
+    __HAL_UART_CLEAR_FLAG(huart, UART_CLEAR_OREF); /* Clear ORE flag */
   }
 #endif
-
+  /* Restart receive interrupt after any error */
+  uint8_t index = uart_index(huart);
+  if (index < UART_NUM) {
+    serial_t *obj = rx_callback_obj[index];
+    if (!serial_rx_active(obj)) {
+      HAL_UART_Receive_IT(uart_handlers[obj->index], &(obj->recv), 1);
+    }
+  }
   UNUSED(tmpval);
 }