diff options
| author | Andiry Xu <andiry.xu@amd.com> | 2010-08-09 13:56:15 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2010-08-23 20:50:16 -0700 |
| commit | 14184f9b8047026f1812f49df074e89dad3a09bc (patch) | |
| tree | 5492adad4d8ce5d263abbdad713c13a35b08202c | |
| parent | a1669b2c64a9c8b031e0ac5cbf2692337a577f7c (diff) | |
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: Sander Eikelenboom <linux@eikelenboom.it>
Tested-by: Sander Eikelenboom <linux@eikelenboom.it>
Signed-off-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| -rw-r--r-- | drivers/usb/host/xhci-ring.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index 2f19f3a817c..48e60d166ff 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/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); } |