Commit f66eef8f authored by Thinh Nguyen's avatar Thinh Nguyen Committed by Greg Kroah-Hartman
Browse files

usb: dwc3: gadget: Delay issuing End Transfer 



If the controller hasn't DMA'ed the Setup data from its fifo, it won't
process the End Transfer command. Polling for the command completion may
block the driver from servicing the Setup phase and cause a timeout.
Previously we only check and delay issuing End Transfer in the case of
endpoint dequeue. Let's do that for all End Transfer scenarios.

Signed-off-by: default avatarThinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/2fcf3b5d90068d549589a57a27a79f76c6769b04.1650593829.git.Thinh.Nguyen@synopsys.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent ace17b6e

drivers/usb/dwc3/gadget.c

+12 −10
Original line number Diff line number Diff line
@@ -2062,16 +2062,6 @@ static int dwc3_gadget_ep_dequeue(struct usb_ep *ep, 
		if (r == req) {

			struct dwc3_request *t;



			/*

			 * If a Setup packet is received but yet to DMA out, the controller will

			 * not process the End Transfer command of any endpoint. Polling of its

			 * DEPCMD.CmdAct may block setting up TRB for Setup packet, causing a

			 * timeout. Delay issuing the End Transfer command until the Setup TRB is

			 * prepared.

			 */

			if (dwc->ep0state != EP0_SETUP_PHASE && !dwc->delayed_status)

				dep->flags |= DWC3_EP_DELAY_STOP;



			/* wait until it is processed */

			dwc3_stop_active_transfer(dep, true, true);
@@ -3701,6 +3691,18 @@ void dwc3_stop_active_transfer(struct dwc3_ep *dep, bool force, 
	    (dep->flags & DWC3_EP_END_TRANSFER_PENDING))

		return;



	/*

	 * If a Setup packet is received but yet to DMA out, the controller will

	 * not process the End Transfer command of any endpoint. Polling of its

	 * DEPCMD.CmdAct may block setting up TRB for Setup packet, causing a

	 * timeout. Delay issuing the End Transfer command until the Setup TRB is

	 * prepared.

	 */

	if (dwc->ep0state != EP0_SETUP_PHASE && !dwc->delayed_status) {

		dep->flags |= DWC3_EP_DELAY_STOP;

		return;

	}



	/*

	 * NOTICE: We are violating what the Databook says about the

	 * EndTransfer command. Ideally we would _always_ wait for the