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-rw-r--r--drivers/usb/host/xhci-ring.c11
1 files changed, 11 insertions, 0 deletions
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 23b4aefd103..8275645889d 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -885,6 +885,17 @@ static void update_ring_for_set_deq_completion(struct xhci_hcd *xhci,
num_trbs_free_temp = ep_ring->num_trbs_free;
dequeue_temp = ep_ring->dequeue;
+ /* If we get two back-to-back stalls, and the first stalled transfer
+ * ends just before a link TRB, the dequeue pointer will be left on
+ * the link TRB by the code in the while loop. So we have to update
+ * the dequeue pointer one segment further, or we'll jump off
+ * the segment into la-la-land.
+ */
+ if (last_trb(xhci, ep_ring, ep_ring->deq_seg, ep_ring->dequeue)) {
+ ep_ring->deq_seg = ep_ring->deq_seg->next;
+ ep_ring->dequeue = ep_ring->deq_seg->trbs;
+ }
+
while (ep_ring->dequeue != dev->eps[ep_index].queued_deq_ptr) {
/* We have more usable TRBs */
ep_ring->num_trbs_free++;