usb-xhci: Handle COMP_TX_ERR for isoc tds

While testing unplugging an UVC HD webcam with usb-redirection (so through
usbdevfs), my userspace usb-redir code was getting a value of -1 in
iso_frame_desc[n].status, which according to Documentation/usb/error-codes.txt
is not a valid value.

The source of this -1 is the default case in xhci-ring.c:process_isoc_td()
adding a kprintf there showed the value of trb_comp_code to be COMP_TX_ERR
in this case, so this patch adds handling for that completion code to
process_isoc_td().

This was observed and tested with the following xhci controller:
1033:0194 NEC Corporation uPD720200 USB 3.0 Host Controller (rev 04)

Note: I also wonder if setting frame->status to -1 (-EPERM) is the best we can
do, but since I cannot come up with anything better I've left that as is.

This patch should be backported to kernels as old as 2.6.36, which contain the
commit 04e51901dd44f40a5a385ced897f6bca87d5f40a "USB: xHCI: Isochronous
transfer implementation".

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index cb1de111daeef8695ebccae6e3cacc404a837b47..d40194c8ca60fc78f6c149c986ce8dc442407993 100644 (file)
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -1804,6 +1804,7 @@ static int process_isoc_td(struct xhci_hcd *xhci, struct xhci_td *td,
                break;
        case COMP_DEV_ERR:
        case COMP_STALL:
+       case COMP_TX_ERR:
                frame->status = -EPROTO;
                skip_td = true;
                break;