USB control data transfer (vendor request)

[dimgit]

Hi,

I am using a custom vendor handler (typedef int (*usb_request_handler)(struct usb_setup_packet *setup, int32_t *transfer_len, uint8_t **payload_data)) , to process vendor specific control requests.
For control requests that have data stage, for example when device needs to send data to host, I can set transfer_len and payload_data, as needed and the data gets sent to the host. However, I do not see a way to receive notification when the data transmission has completed. Is this limitation of the current design, or maybe I am missing something?

Thank you,
D.