If the difference is big enough between the bytes asked and received
in a bulk tranfer we can get a short transfer event pointing to a TRB in
the middle of the TD. We don't want to handle the TD yet as we will anyway
receive a new event for the last TRB in the TD.

Hold off removing TD from list and finishing it before we reveive a event
for the last TRB in the TD

Signed-off-by: Mathias Nyman <[email protected]>
---
 drivers/usb/host/xhci-ring.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index a47a1e8..4d3cb61 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -2182,6 +2182,10 @@ static int process_bulk_intr_td(struct xhci_hcd *xhci, 
struct xhci_td *td,
                }
        /* Fast path - was this the last TRB in the TD for this URB? */
        } else if (event_trb == td->last_trb) {
+               if (td->urb_length_set && trb_comp_code == COMP_SHORT_TX)
+                       return finish_td(xhci, td, event_trb, event, ep,
+                                        status, false);
+
                if (EVENT_TRB_LEN(le32_to_cpu(event->transfer_len)) != 0) {
                        td->urb->actual_length =
                                td->urb->transfer_buffer_length -
@@ -2233,6 +2237,12 @@ static int process_bulk_intr_td(struct xhci_hcd *xhci, 
struct xhci_td *td,
                        td->urb->actual_length +=
                                TRB_LEN(le32_to_cpu(cur_trb->generic.field[2])) 
-
                                EVENT_TRB_LEN(le32_to_cpu(event->transfer_len));
+
+               if (trb_comp_code == COMP_SHORT_TX) {
+                       xhci_dbg(xhci, "mid bulk/intr SP, wait for last TRB 
event\n");
+                       td->urb_length_set = true;
+                       return 0;
+               }
        }
 
        return finish_td(xhci, td, event_trb, event, ep, status, false);
-- 
1.9.1

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