[PATCH 4.19 126/131] usb: dwc3: gadget: Fix request completion check

[Greg Kroah-Hartman]

From: Thinh Nguyen <Thinh.Nguyen@xxxxxxxxxxxx>

commit 49e0590e3a60e75b493e5df879e216e5073c7663 upstream.

A request may not be completed because not all the TRBs are prepared for
it. This happens when we run out of available TRBs. When some TRBs are
completed, the driver needs to prepare the rest of the TRBs for the
request. The check dwc3_gadget_ep_request_completed() shouldn't be
checking the amount of data received but rather the number of pending
TRBs. Revise this request completion check.

Cc: stable@xxxxxxxxxxxxxxx
Fixes: e0c42ce590fe ("usb: dwc3: gadget: simplify IOC handling")
Signed-off-by: Thinh Nguyen <thinhn@xxxxxxxxxxxx>
Signed-off-by: Felipe Balbi <balbi@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/usb/dwc3/gadget.c |   12 ++----------
 1 file changed, 2 insertions(+), 10 deletions(-)

--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -2280,14 +2280,7 @@ static int dwc3_gadget_ep_reclaim_trb_li
 
 static bool dwc3_gadget_ep_request_completed(struct dwc3_request *req)
 {
-	/*
-	 * For OUT direction, host may send less than the setup
-	 * length. Return true for all OUT requests.
-	 */
-	if (!req->direction)
-		return true;
-
-	return req->request.actual == req->request.length;
+	return req->num_pending_sgs == 0;
 }
 
 static int dwc3_gadget_ep_cleanup_completed_request(struct dwc3_ep *dep,
@@ -2311,8 +2304,7 @@ static int dwc3_gadget_ep_cleanup_comple
 
 	req->request.actual = req->request.length - req->remaining;
 
-	if (!dwc3_gadget_ep_request_completed(req) ||
-			req->num_pending_sgs) {
+	if (!dwc3_gadget_ep_request_completed(req)) {
 		__dwc3_gadget_kick_transfer(dep);
 		goto out;
 	}