From da10bcdd6f70dc9977f2cf18f4783cf78520623a Mon Sep 17 00:00:00 2001 From: Thinh Nguyen Date: Wed, 18 Dec 2019 18:14:50 -0800 Subject: usb: dwc3: gadget: Delay starting transfer If the END_TRANSFER command hasn't completed yet, then don't send the START_TRANSFER command. The controller may not be able to start if that's the case. Some controller revisions depend on this. See commit 76a638f8ac0d ("usb: dwc3: gadget: wait for End Transfer to complete"). Let's only send START_TRANSFER command after the END_TRANSFER command had completed. Fixes: 3aec99154db3 ("usb: dwc3: gadget: remove DWC3_EP_END_TRANSFER_PENDING") Signed-off-by: Thinh Nguyen Signed-off-by: Felipe Balbi Signed-off-by: Greg Kroah-Hartman --- drivers/usb/dwc3/gadget.c | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'drivers/usb/dwc3/gadget.c') diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index cf163dcc5524..696fbeb8d03a 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -1450,6 +1450,12 @@ static int __dwc3_gadget_ep_queue(struct dwc3_ep *dep, struct dwc3_request *req) list_add_tail(&req->list, &dep->pending_list); req->status = DWC3_REQUEST_STATUS_QUEUED; + /* Start the transfer only after the END_TRANSFER is completed */ + if (dep->flags & DWC3_EP_END_TRANSFER_PENDING) { + dep->flags |= DWC3_EP_DELAY_START; + return 0; + } + /* * NOTICE: Isochronous endpoints should NEVER be prestarted. We must * wait for a XferNotReady event so we will know what's the current @@ -2631,6 +2637,11 @@ static void dwc3_endpoint_interrupt(struct dwc3 *dwc, dep->flags &= ~DWC3_EP_END_TRANSFER_PENDING; dep->flags &= ~DWC3_EP_TRANSFER_STARTED; dwc3_gadget_ep_cleanup_cancelled_requests(dep); + if ((dep->flags & DWC3_EP_DELAY_START) && + !usb_endpoint_xfer_isoc(dep->endpoint.desc)) + __dwc3_gadget_kick_transfer(dep); + + dep->flags &= ~DWC3_EP_DELAY_START; } break; case DWC3_DEPEVT_STREAMEVT: -- cgit v1.2.3