Commit da10bcdd authored by Thinh Nguyen's avatar Thinh Nguyen Committed by Greg Kroah-Hartman
Browse files

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 76a638f8 ("usb: dwc3: gadget: wait for End Transfer to
complete"). Let's only send START_TRANSFER command after the
END_TRANSFER command had completed.

Fixes: 3aec9915 ("usb: dwc3: gadget: remove DWC3_EP_END_TRANSFER_PENDING")
Signed-off-by: default avatarThinh Nguyen <thinhn@synopsys.com>
Signed-off-by: default avatarFelipe Balbi <balbi@kernel.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent c58d8bfc

drivers/usb/dwc3/core.h

+1 −0
Original line number Diff line number Diff line
@@ -690,6 +690,7 @@ struct dwc3_ep { 
#define DWC3_EP_TRANSFER_STARTED BIT(3)

#define DWC3_EP_END_TRANSFER_PENDING BIT(4)

#define DWC3_EP_PENDING_REQUEST	BIT(5)

#define DWC3_EP_DELAY_START	BIT(6)



	/* This last one is specific to EP0 */

#define DWC3_EP0_DIR_IN		BIT(31)

drivers/usb/dwc3/gadget.c

+11 −0
Original line number Diff line number Diff line
@@ -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: