On 9/13/23 17:00, Artur Rojek wrote:
In the existing implementation, multiple requests queued up on an endpoint are subject to getting evicted without transmission.
For both control and bulk endpoints, their respective logic found in usba_control_irq()/usba_ep_irq() guarantees that TX FIFO is empty before data is sent out, and that request_complete() gets called once the transaction has been finished. At this point however, if any additional requests are found on the endpoint queue, they will be processed by submit_next_request(), which makes no checks against the above conditions, trashing data on a busy FIFO and neglecting completion handlers.
Fix the above issues by removing the calls to submit_next_request(), and thus forcing the pending requests to be processed on the next pass of the respective endpoint logic. While at it, remove a DBG message, as that branch becomes part of regular flow.
This restores mass storage mode operation on Microchip ATSAMA5D27 SoC.
Updated subject prefix to lowercase usb: and applied to usb/next, thanks.