This reverts commit e210c422b6fd ("xhci: don't finish a TD if we get a
short transfer event mid TD")
Turns out that most host controllers do not follow the xHCI specs and never
send the second event for the last TRB in the TD if there was a short event
mid-TD.
Returning the URB directly after the first short-transfer event is far
better than never returning the URB. (class drivers usually timeout
after 30sec). For the hosts that do send the second event we will go
back to treating it as misplaced event and print an error message for it.
The origial patch was sent to stable kernels and needs to be reverted from
there as well
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
---
drivers/usb/host/xhci-ring.c | 10 ----------
1 file changed, 10 deletions(-)
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index f1c21c4..3915657 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -2193,10 +2193,6 @@ 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 -
@@ -2248,12 +2244,6 @@ 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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