From c503672abe1348f10f5a54a662336358c6e1a297 Mon Sep 17 00:00:00 2001
From: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Date: Wed, 2 Sep 2020 18:42:58 -0700
Subject: [PATCH] usb: dwc3: gadget: Resume pending requests after CLEAR_STALL
Git-commit: c503672abe1348f10f5a54a662336358c6e1a297
Patch-mainline: v5.10-rc1
References: git-fixes

The function driver may queue new requests right after halting the
endpoint (i.e. queue new requests while the endpoint is stalled).
There's no restriction preventing it from doing so. However, dwc3
currently drops those requests after CLEAR_STALL. The driver should only
drop started requests. Keep the pending requests in the pending list to
resume and process them after the host issues ClearFeature(Halt) to the
endpoint.

Cc: stable@vger.kernel.org
Fixes: cb11ea56f37a ("usb: dwc3: gadget: Properly handle ClearFeature(halt)")
Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/usb/dwc3/gadget.c |   22 ++++++++++++++--------
 1 file changed, 14 insertions(+), 8 deletions(-)

--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -1462,8 +1462,13 @@ static int __dwc3_gadget_ep_queue(struct
 	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) {
+	/*
+	 * Start the transfer only after the END_TRANSFER is completed
+	 * and endpoint STALL is cleared.
+	 */
+	if ((dep->flags & DWC3_EP_END_TRANSFER_PENDING) ||
+	    (dep->flags & DWC3_EP_WEDGE) ||
+	    (dep->flags & DWC3_EP_STALL)) {
 		dep->flags |= DWC3_EP_DELAY_START;
 		return 0;
 	}
@@ -1669,13 +1674,14 @@ int __dwc3_gadget_ep_set_halt(struct dwc
 		list_for_each_entry_safe(req, tmp, &dep->started_list, list)
 			dwc3_gadget_move_cancelled_request(req);
 
-		list_for_each_entry_safe(req, tmp, &dep->pending_list, list)
-			dwc3_gadget_move_cancelled_request(req);
-
-		if (!(dep->flags & DWC3_EP_END_TRANSFER_PENDING)) {
-			dep->flags &= ~DWC3_EP_DELAY_START;
+		if (!(dep->flags & DWC3_EP_END_TRANSFER_PENDING))
 			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;
 	}
 
 	return ret;