Check for event queue overflow in usbd / dcd_event_handler

[Erlkoenig90]

When using osal_queue_send to send events to the queue _usbd_q in udbd.c's dcd_event_handler, the queue may overflow (particularly if the application calls usbd_defer_func too often). In that case, events will be missed, leading to spurious and hard-to-debug errors (for example, IN data is sent, ISR is called, but nothing else happens).

Therefore I'd like to suggest adding TU_ASSERT around the calls to osal_queue_send in order to make finding these bugs easier.

[hathach]

which RTOS you are using, the osal_none does have an TU_ASSERT() when adding item to queue.

[Erlkoenig90]

I'm using FreeRTOS, via ESP-IDF. What's the point of the return value in osal_queue_send if there is a TU_ASSERT, i.e. the return value is supped to be always true?

[hathach]

thank you for the Pr, and sorry for late response. I have rebased and add check for queuing new usb event