The last TRB of a isoc TD might not trigger an event if there was
an error event for TRB mid TD. This is seen on a NEC Corporation
uPD720200 USB 3.0 Host
Driver and xHC host get out of sync as driver is still expecting a
transfer event for that first TD, while xHC host is already sending
events for the next TD in the list. This leads to
"Transfer event TRB DMA ptr not part of current TD" messages.
As a solution we tag the isoc TDs that get error events mid TD.
If an event doesn't match the first TD, then check if the tag is
set, and event points to the next TD.
In that case give back the fist TD and process the next TD normally
Reported-by: Michał Pecio <michal.pecio@xxxxxxxxx>
Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
---
drivers/usb/host/xhci-ring.c | 55 +++++++++++++++++++++++++++---------
drivers/usb/host/xhci.h | 1 +
2 files changed, 42 insertions(+), 14 deletions(-)
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 33806ae966f9..4869005379f5 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -2401,8 +2401,11 @@ static int process_isoc_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
break;
case COMP_USB_TRANSACTION_ERROR:
frame->status = -EPROTO;
- if (ep_trb != td->last_trb)
+ if (ep_trb != td->last_trb) {
+ td->error_mid_td = true;
+ /* FIXME update actual_length */
return 0;
+ }
break;
case COMP_STOPPED:
sum_trbs_for_length = true;
@@ -2808,17 +2811,44 @@ static int handle_tx_event(struct xhci_hcd *xhci,
}
if (!ep_seg) {
- if (!ep->skip ||
- !usb_endpoint_xfer_isoc(&td->urb->ep->desc)) {
- /* Some host controllers give a spurious
- * successful event after a short transfer.
- * Ignore it.
- */
- if ((xhci->quirks & XHCI_SPURIOUS_SUCCESS) &&
- ep_ring->last_td_was_short) {
- ep_ring->last_td_was_short = false;
- goto cleanup;
+
+ if (ep->skip && usb_endpoint_xfer_isoc(&td->urb->ep->desc)) {
+ skip_isoc_td(xhci, td, ep, status);
+ goto cleanup;
+ }
+
+ /*
+ * Some hosts give a spurious success event after a short
+ * transfer. Ignore it.
+ */
+ if ((xhci->quirks & XHCI_SPURIOUS_SUCCESS) &&
+ ep_ring->last_td_was_short) {
+ ep_ring->last_td_was_short = false;
+ goto cleanup;
+ }
+
+ /*
+ * if there was an error event mid TD then host may not
+ * give an event for the last TRB on an isoc TD.
+ * This event can be for the next TD, See xHCI 4.9.1.
+ */
+ if (td->error_mid_td) {
+ struct xhci_td *td_next = list_next_entry(td, td_list);
+
+ ep_seg = trb_in_td(xhci, td_next->start_seg, td_next->first_trb,
+ td_next->last_trb, ep_trb_dma, false);
+ if (ep_seg) {
+ /* give back previous TD, start handling new */
+ ep_ring->dequeue = td->last_trb;
+ ep_ring->deq_seg = td->last_trb_seg;
+ inc_deq(xhci, ep_ring);
+ xhci_td_cleanup(xhci, td, ep_ring, td->status);
+ td = td_next;
}
+
+ }
+
+ if (!ep_seg) {
/* HC is busted, give up! */
xhci_err(xhci,
"ERROR Transfer event TRB DMA ptr not "
@@ -2830,9 +2860,6 @@ static int handle_tx_event(struct xhci_hcd *xhci,
ep_trb_dma, true);
return -ESHUTDOWN;
}
-
- skip_isoc_td(xhci, td, ep, status);
- goto cleanup;
}
if (trb_comp_code == COMP_SHORT_PACKET)
ep_ring->last_td_was_short = true;
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index a5c72a634e6a..6f82d404883f 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1549,6 +1549,7 @@ struct xhci_td {
struct xhci_segment *bounce_seg;
/* actual_length of the URB has already been set */
bool urb_length_set;
+ bool error_mid_td;
unsigned int num_trbs;
};
--
2.25.1
