USB: xHCI: update ring dequeue pointer when process missed tds

This patch fixes a isoc transfer bug reported by Sander Eikelenboom.
When ep->skip is set, endpoint ring dequeue pointer should be updated
when processed every missed td. Although ring dequeue pointer will also
be updated when ep->skip is clear, leave it intact during missed tds
processing may cause two issues:

1). If the very next valid transfer following missed tds is a short
transfer, its actual_length will be miscalculated;
2). If there are too many missed tds during transfer, new inserted tds
may found the transfer ring full and urb enqueue fails.
Reported-by: NSander Eikelenboom <linux@eikelenboom.it>
Tested-by: NSander Eikelenboom <linux@eikelenboom.it>
Signed-off-by: NAndiry Xu <andiry.xu@amd.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/usb/host/xhci-ring.c

@@ -1551,6 +1551,10 @@ static int process_isoc_td(struct xhci_hcd *xhci, struct xhci_td *td,
 	/* calc actual length */
 	if (ep->skip) {
 		td->urb->iso_frame_desc[idx].actual_length = 0;
+		/* Update ring dequeue pointer */
+		while (ep_ring->dequeue != td->last_trb)
+			inc_deq(xhci, ep_ring, false);
+		inc_deq(xhci, ep_ring, false);
 		return finish_td(xhci, td, event_trb, event, ep, status, true);
 	}