Blob Blame History Raw
From f66eef8fb8989a7193cafc3870f7c7b2b97f16cb Mon Sep 17 00:00:00 2001
From: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Date: Thu, 21 Apr 2022 19:23:03 -0700
Subject: [PATCH] usb: dwc3: gadget: Delay issuing End Transfer
Git-commit: f66eef8fb8989a7193cafc3870f7c7b2b97f16cb
References: git-fixes
Patch-mainline: v5.19-rc1

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: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/2fcf3b5d90068d549589a57a27a79f76c6769b04.1650593829.git.Thinh.Nguyen@synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Oliver Neukum <oneukum@suse.com>
---
 drivers/usb/dwc3/gadget.c | 22 ++++++++++++----------
 1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 4f445f836d32..4f54f0ef21df 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -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
-- 
2.40.1