From 2338484d14f3f4b3bd1f7bb416805976e7bd0cc5 Mon Sep 17 00:00:00 2001 From: Thinh Nguyen Date: Wed, 30 Sep 2020 17:44:38 -0700 Subject: [PATCH] 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 Signed-off-by: Felipe Balbi --- drivers/usb/dwc3/gadget.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index ff924656f690..da1f2ad2ad90 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -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;