Raise Serial/SerialUSB interrupts to user code

cores/arduino/HardwareSerial.cpp

@@ -347,6 +347,12 @@ void HardwareSerial::_rx_complete_irq(serial_t *obj)
       obj->rx_head = i;
     }
   }
+
+  // Raise user event callback if registered
+  if (obj->event_callback)
+  {
+    obj->event_callback(SERIAL_EVENT_RX);
+  }
 }
 
 // Actual interrupt handlers //////////////////////////////////////////////////
@@ -368,7 +374,11 @@ int HardwareSerial::_tx_complete_irq(serial_t *obj)
     uart_attach_tx_callback(obj, _tx_complete_irq, obj->tx_size);
     return -1;
   }
-
+  // Raise user event callback if registered
+  if (obj->event_callback)
+  {
+    obj->event_callback(SERIAL_EVENT_TX);
+  }
   return 0;
 }
 
@@ -655,4 +665,12 @@ void HardwareSerial::enableHalfDuplexRx(void)
   }
 }
 
+void HardwareSerial::onEvent(SerialCallback_t callback)
+{
+  if (callback)
+  {
+    _serial.event_callback = callback;
+  }
+}
+
 #endif // HAL_UART_MODULE_ENABLED && !HAL_UART_MODULE_ONLY

cores/arduino/HardwareSerial.h

@@ -169,6 +169,7 @@ class HardwareSerial : public Stream {
     void setHalfDuplex(void);
     bool isHalfDuplex(void) const;
     void enableHalfDuplexRx(void);
+    void onEvent(SerialCallback_t event_callback);
 
     friend class STM32LowPower;
 

cores/arduino/USBSerial.cpp

@@ -197,4 +197,12 @@ USBSerial::operator bool()
   return dtrState;
 }
 
+void USBSerial::onEvent(USBSerialCallback_t callback)
+{
+  if (callback)
+  {
+    CDC_register_cb(callback);
+  }
+}
+
 #endif // USBCON && USBD_USE_CDC

cores/arduino/USBSerial.h

@@ -22,6 +22,7 @@
 #if defined (USBCON) && defined(USBD_USE_CDC)
 #include "Stream.h"
 #include "usbd_core.h"
+#include "usbd_cdc_if.h"
 
 //================================================================================
 // Serial over CDC
@@ -43,6 +44,7 @@ class USBSerial : public Stream {
     virtual size_t write(const uint8_t *buffer, size_t size);
     using Print::write; // pull in write(str) from Print
     operator bool(void);
+    void onEvent(USBSerialCallback_t callback);
 
     // These return the settings specified by the USB host for the
     // serial port. These aren't really used, but are offered here

cores/arduino/stm32/uart.h

@@ -59,6 +59,13 @@ extern "C" {
 /* Exported types ------------------------------------------------------------*/
 typedef struct serial_s serial_t;
 
+typedef enum {
+  SERIAL_EVENT_TX,
+  SERIAL_EVENT_RX
+} SerialEvent_t;
+
+typedef void (*SerialCallback_t)(SerialEvent_t event);
+
 struct serial_s {
   /*  The 1st 2 members USART_TypeDef *uart
    *  and UART_HandleTypeDef handle should
@@ -69,6 +76,7 @@ struct serial_s {
   UART_HandleTypeDef handle;
   void (*rx_callback)(serial_t *);
   int (*tx_callback)(serial_t *);
+  SerialCallback_t event_callback;
   PinName pin_tx;
   PinName pin_rx;
   PinName pin_rts;

cores/arduino/stm32/usb/cdc/usbd_cdc_if.c

@@ -59,6 +59,7 @@ __IO bool dtrState = false; /* lineState */
 __IO bool rtsState = false;
 __IO bool receivePended = true;
 static uint32_t transmitStart = 0;
+static USBSerialCallback_t eventCallback;
 
 #ifdef DTR_TOGGLING_SEQ
   /* DTR toggling sequence management */
@@ -244,6 +245,10 @@ static int8_t USBD_CDC_Receive(uint8_t *Buf, uint32_t *Len)
   if (!CDC_resume_receive()) {
     USBD_CDC_ClearBuffer(&hUSBD_Device_CDC);
   }
+  // Raise user event callback if registered
+  if (eventCallback) {
+    eventCallback(USB_SERIAL_EVENT_RX);
+  }
   return ((int8_t)USBD_OK);
 }
 
@@ -268,6 +273,10 @@ static int8_t USBD_CDC_TransmitCplt(uint8_t *Buf, uint32_t *Len, uint8_t epnum)
   transmitStart = 0;
   CDC_TransmitQueue_CommitRead(&TransmitQueue);
   CDC_continue_transmit();
+  // Raise user event callback if registered
+  if (eventCallback) {
+    eventCallback(USB_SERIAL_EVENT_TX);
+  }
   return ((int8_t)USBD_OK);
 }
 
@@ -379,6 +388,21 @@ void CDC_enableDTR(bool enable)
   CDC_DTR_enabled = enable;
 }
 
+/**
+  * @brief  CDC_register_cb
+  *         Register USBCDC event callback
+  * @param  callback: Pointer to user callback function
+  * @retval Result of the operation: USBD_OK if all operations are OK else USBD_FAIL
+  */
+int8_t CDC_register_cb(USBSerialCallback_t callback)
+{
+  if (callback) {
+    eventCallback = callback;
+    return ((int8_t)USBD_OK);
+  }
+  return ((int8_t)USBD_FAIL);
+}
+
 #endif /* USBD_USE_CDC */
 #endif /* USBCON */
 /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/

cores/arduino/stm32/usb/cdc/usbd_cdc_if.h

@@ -37,6 +37,13 @@ extern "C" {
 #define CDC_POLLING_INTERVAL             2 /* in ms. The max is 65 and the min is 1 */
 
 /* Exported types ------------------------------------------------------------*/
+typedef enum {
+  USB_SERIAL_EVENT_TX,
+  USB_SERIAL_EVENT_RX
+} USBSerialEvent_t;
+
+typedef void (*USBSerialCallback_t)(USBSerialEvent_t);
+
 /* Exported constants --------------------------------------------------------*/
 
 extern USBD_CDC_ItfTypeDef  USBD_CDC_fops;
@@ -52,6 +59,7 @@ void CDC_init(void);
 void CDC_deInit(void);
 bool CDC_connected(void);
 void CDC_enableDTR(bool enable);
+int8_t CDC_register_cb(USBSerialCallback_t callback);
 
 #ifdef __cplusplus
 }