RE: [PATCH v3] usb: dwc3: gadget: trb_dequeue is not updated properly

From: Yang, Fei
Date: Tue Jul 23 2019 - 14:53:17 EST


>> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
>> index 173f532..88eed49 100644
>> --- a/drivers/usb/dwc3/gadget.c
>> +++ b/drivers/usb/dwc3/gadget.c
>> @@ -2394,7 +2394,7 @@ static int dwc3_gadget_ep_reclaim_completed_trb(struct dwc3_ep *dep,
>> if (event->status & DEPEVT_STATUS_SHORT && !chain)
>> return 1;
>>
>> - if (event->status & DEPEVT_STATUS_IOC)
>> + if (event->status & DEPEVT_STATUS_IOC && !chain)
>> return 1;
>
> This will break the situation when we have more SGs than available TRBs. In that case we set IOC before the last so we have time to update transfer to append more TRBs.
What's your opinion on https://patchwork.kernel.org/patch/10640137/? Checking condition "(event->status & DEPEVT_STATUS_IOC) && (trb->ctrl & DWC3_TRB_CTRL_IOC)"
won't cause problem handling TRB shortage cases, right?

> Please, send me tracepoints
I sent you the tracepoints last Friday, any new findings?