Re: [PATCH] usb: dwc3: gadget: Avoid canceling current request for queuing error

From: Wesley Cheng
Date: Thu Apr 15 2021 - 13:51:18 EST




On 4/14/2021 11:26 PM, Felipe Balbi wrote:
> Wesley Cheng <wcheng@xxxxxxxxxxxxxx> writes:
>
>> If an error is received when issuing a start or update transfer
>> command, the error handler will stop all active requests (including
>> the current USB request), and call dwc3_gadget_giveback() to notify
>> function drivers of the requests which have been stopped. Avoid
>> having to cancel the current request which is trying to be queued, as
>> the function driver will handle the EP queue error accordingly.
>> Simply unmap the request as it was done before, and allow previously
>> started transfers to be cleaned up.
>>
>> Signed-off-by: Wesley Cheng <wcheng@xxxxxxxxxxxxxx>
>> ---
>> drivers/usb/dwc3/gadget.c | 5 +++++
>> 1 file changed, 5 insertions(+)
>>
>> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
>> index e1b04c97..4200775 100644
>> --- a/drivers/usb/dwc3/gadget.c
>> +++ b/drivers/usb/dwc3/gadget.c
>> @@ -1399,6 +1399,11 @@ static int __dwc3_gadget_kick_transfer(struct dwc3_ep *dep)
>> if (ret == -EAGAIN)
>> return ret;
>>
>> + /* Avoid canceling current request, as it has not been started */
>> + if (req->trb)
>> + memset(req->trb, 0, sizeof(struct dwc3_trb));
>
> we don't need a full memset. I think ensuring HWO bit is zero is enough.
>
Hi Felipe,

Thanks for the input/review, will make this change to just clear the HWO.

Thanks
Wesley Cheng

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