usb: dwc3: gadget: Return early if no TRB update

If the transfer had already started and there's no TRB to update, then
there's no need to go through __dwc3_gadget_kick_transfer(). There is
no problem reissuing UPDATE_TRANSFER command. This change just saves
the driver from doing a few operations. This happens when we run out of
TRB and function driver still queues for more requests.

Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
This commit is contained in:
Thinh Nguyen 2020-09-30 17:44:38 -07:00 committed by Felipe Balbi
parent 346a15cdf6
commit 2338484d14

View File

@ -1347,6 +1347,13 @@ static int __dwc3_gadget_kick_transfer(struct dwc3_ep *dep)
starting = !(dep->flags & DWC3_EP_TRANSFER_STARTED);
/*
* If there's no new TRB prepared and we don't need to restart a
* transfer, there's no need to update the transfer.
*/
if (!ret && !starting)
return ret;
req = next_request(&dep->started_list);
if (!req) {
dep->flags |= DWC3_EP_PENDING_REQUEST;