---

yaml
---
r: 235449
b: refs/heads/master
c: 01a1fdb
h: refs/heads/master
i:
  235447: 1eda443
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: bf161e85fb153c0dd5a95faca73fd6a9d237c389
+refs/heads/master: 01a1fdb9a7afa5e3c14c9316d6f380732750b4e4

trunk/drivers/usb/host/xhci-ring.c

@@ -495,6 +495,20 @@ void xhci_find_new_dequeue_state(struct xhci_hcd *xhci,
 		state->new_cycle_state = ~(state->new_cycle_state) & 0x1;
 	next_trb(xhci, ep_ring, &state->new_deq_seg, &state->new_deq_ptr);
 
+	/*
+	 * If there is only one segment in a ring, find_trb_seg()'s while loop
+	 * will not run, and it will return before it has a chance to see if it
+	 * needs to toggle the cycle bit.  It can't tell if the stalled transfer
+	 * ended just before the link TRB on a one-segment ring, or if the TD
+	 * wrapped around the top of the ring, because it doesn't have the TD in
+	 * question.  Look for the one-segment case where stalled TRB's address
+	 * is greater than the new dequeue pointer address.
+	 */
+	if (ep_ring->first_seg == ep_ring->first_seg->next &&
+			state->new_deq_ptr < dev->eps[ep_index].stopped_trb)
+		state->new_cycle_state ^= 0x1;
+	xhci_dbg(xhci, "Cycle state = 0x%x\n", state->new_cycle_state);
+
 	/* Don't update the ring cycle state for the producer (us). */
 	xhci_dbg(xhci, "New dequeue segment = %p (virtual)\n",
 			state->new_deq_seg);