3 files changed, 117 insertions, 50 deletions

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index 6d8f7e32932a..64d036804715 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -1124,6 +1124,7 @@ int xhci_endpoint_init(struct xhci_hcd *xhci,
                 virt_dev->num_rings_cached--;
                 xhci_reinit_cached_ring(xhci, virt_dev->eps[ep_index].new_ring);
         }
+        virt_dev->eps[ep_index].skip = false;
         ep_ring = virt_dev->eps[ep_index].new_ring;
         ep_ctx->deq = ep_ring->first_seg->dma | ep_ring->cycle_state;
 
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 5bb12fed9d2d..4c3501003b8e 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -1675,6 +1675,16 @@ static int handle_tx_event(struct xhci_hcd *xhci,
                                         "still with TDs queued?\n",
                                 TRB_TO_SLOT_ID(event->flags), ep_index);
                 goto cleanup;
+        case COMP_MISSED_INT:
+                /*
+                 * When encounter missed service error, one or more isoc tds
+                 * may be missed by xHC.
+                 * Set skip flag of the ep_ring; Complete the missed tds as
+                 * short transfer when process the ep_ring next time.
+                 */
+                ep->skip = true;
+                xhci_dbg(xhci, "Miss service interval error, set skip flag\n");
+                goto cleanup;
         default:
                 if (xhci_is_vendor_info_code(xhci, trb_comp_code)) {
                         status = 0;
@@ -1685,60 +1695,108 @@ static int handle_tx_event(struct xhci_hcd *xhci,
                 goto cleanup;
         }
 
-        /* This TRB should be in the TD at the head of this ring's TD list */
-        if (list_empty(&ep_ring->td_list)) {
-                xhci_warn(xhci, "WARN Event TRB for slot %d ep %d with no TDs queued?\n",
-                                TRB_TO_SLOT_ID(event->flags), ep_index);
-                xhci_dbg(xhci, "Event TRB with TRB type ID %u\n",
-                                (unsigned int) (event->flags & TRB_TYPE_BITMASK)>>10);
-                xhci_print_trb_offsets(xhci, (union xhci_trb *) event);
-                goto cleanup;
-        }
-        td = list_entry(ep_ring->td_list.next, struct xhci_td, td_list);
-
-        /* Is this a TRB in the currently executing TD? */
-        event_seg = trb_in_td(ep_ring->deq_seg, ep_ring->dequeue,
-                        td->last_trb, event_dma);
-        if (!event_seg) {
-                /* HC is busted, give up! */
-                xhci_err(xhci, "ERROR Transfer event TRB DMA ptr not part of current TD\n");
-                return -ESHUTDOWN;
-        }
-        event_trb = &event_seg->trbs[(event_dma - event_seg->dma) / sizeof(*event_trb)];
+        do {
+                /* This TRB should be in the TD at the head of this ring's
+                 * TD list.
+                 */
+                if (list_empty(&ep_ring->td_list)) {
+                        xhci_warn(xhci, "WARN Event TRB for slot %d ep %d "
+                                        "with no TDs queued?\n",
+                                  TRB_TO_SLOT_ID(event->flags), ep_index);
+                        xhci_dbg(xhci, "Event TRB with TRB type ID %u\n",
+                          (unsigned int) (event->flags & TRB_TYPE_BITMASK)>>10);
+                        xhci_print_trb_offsets(xhci, (union xhci_trb *) event);
+                        if (ep->skip) {
+                                ep->skip = false;
+                                xhci_dbg(xhci, "td_list is empty while skip "
+                                                "flag set. Clear skip flag.\n");
+                        }
+                        ret = 0;
+                        goto cleanup;
+                }
 
-        /* Now update the urb's actual_length and give back to the core */
-        /* Was this a control transfer? */
-        if (usb_endpoint_xfer_control(&td->urb->ep->desc))
-                ret = process_ctrl_td(xhci, td, event_trb, event, ep,
-                                        &status);
-        else
-                ret = process_bulk_intr_td(xhci, td, event_trb, event, ep,
-                                        &status);
+                td = list_entry(ep_ring->td_list.next, struct xhci_td, td_list);
+                /* Is this a TRB in the currently executing TD? */
+                event_seg = trb_in_td(ep_ring->deq_seg, ep_ring->dequeue,
+                                td->last_trb, event_dma);
+                if (event_seg && ep->skip) {
+                        xhci_dbg(xhci, "Found td. Clear skip flag.\n");
+                        ep->skip = false;
+                }
+                if (!event_seg &&
+                   (!ep->skip || !usb_endpoint_xfer_isoc(&td->urb->ep->desc))) {
+                        /* HC is busted, give up! */
+                        xhci_err(xhci, "ERROR Transfer event TRB DMA ptr not "
+                                        "part of current TD\n");
+                        return -ESHUTDOWN;
+                }
 
-cleanup:
-        inc_deq(xhci, xhci->event_ring, true);
-        xhci_set_hc_event_deq(xhci);
+                if (event_seg) {
+                        event_trb = &event_seg->trbs[(event_dma -
+                                         event_seg->dma) / sizeof(*event_trb)];
+                        /*
+                         * No-op TRB should not trigger interrupts.
+                         * If event_trb is a no-op TRB, it means the
+                         * corresponding TD has been cancelled. Just ignore
+                         * the TD.
+                         */
+                        if ((event_trb->generic.field[3] & TRB_TYPE_BITMASK)
+                                         == TRB_TYPE(TRB_TR_NOOP)) {
+                                xhci_dbg(xhci, "event_trb is a no-op TRB. "
+                                                "Skip it\n");
+                                goto cleanup;
+                        }
+                }
 
-        /* FIXME for multi-TD URBs (who have buffers bigger than 64MB) */
-        if (ret) {
-                urb = td->urb;
-                /* Leave the TD around for the reset endpoint function to use
-                 * (but only if it's not a control endpoint, since we already
-                 * queued the Set TR dequeue pointer command for stalled
-                 * control endpoints).
+                /* Now update the urb's actual_length and give back to
+                 * the core
                  */
-                if (usb_endpoint_xfer_control(&urb->ep->desc) ||
-                        (trb_comp_code != COMP_STALL &&
-                                trb_comp_code != COMP_BABBLE))
-                        kfree(td);
-
-                usb_hcd_unlink_urb_from_ep(xhci_to_hcd(xhci), urb);
-                xhci_dbg(xhci, "Giveback URB %p, len = %d, status = %d\n",
-                                urb, urb->actual_length, status);
-                spin_unlock(&xhci->lock);
-                usb_hcd_giveback_urb(xhci_to_hcd(xhci), urb, status);
-                spin_lock(&xhci->lock);
-        }
+                if (usb_endpoint_xfer_control(&td->urb->ep->desc))
+                        ret = process_ctrl_td(xhci, td, event_trb, event, ep,
+                                                 &status);
+                else
+                        ret = process_bulk_intr_td(xhci, td, event_trb, event,
+                                                 ep, &status);
+
+cleanup:
+                /*
+                 * Do not update event ring dequeue pointer if ep->skip is set.
+                 * Will roll back to continue process missed tds.
+                 */
+                if (trb_comp_code == COMP_MISSED_INT || !ep->skip) {
+                        inc_deq(xhci, xhci->event_ring, true);
+                        xhci_set_hc_event_deq(xhci);
+                }
+
+                if (ret) {
+                        urb = td->urb;
+                        /* Leave the TD around for the reset endpoint function
+                         * to use(but only if it's not a control endpoint,
+                         * since we already queued the Set TR dequeue pointer
+                         * command for stalled control endpoints).
+                         */
+                        if (usb_endpoint_xfer_control(&urb->ep->desc) ||
+                                (trb_comp_code != COMP_STALL &&
+                                        trb_comp_code != COMP_BABBLE))
+                                kfree(td);
+
+                        usb_hcd_unlink_urb_from_ep(xhci_to_hcd(xhci), urb);
+                        xhci_dbg(xhci, "Giveback URB %p, len = %d, "
+                                        "status = %d\n",
+                                        urb, urb->actual_length, status);
+                        spin_unlock(&xhci->lock);
+                        usb_hcd_giveback_urb(xhci_to_hcd(xhci), urb, status);
+                        spin_lock(&xhci->lock);
+                }
+
+        /*
+         * If ep->skip is set, it means there are missed tds on the
+         * endpoint ring need to take care of.
+         * Process them as short transfer until reach the td pointed by
+         * the event.
+         */
+        } while (ep->skip && trb_comp_code != COMP_MISSED_INT);
+
         return 0;
 }
 
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 5bc03d1c2beb..f4dfb26a65aa 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -720,6 +720,14 @@ struct xhci_virt_ep {
         struct timer_list       stop_cmd_timer;
         int                     stop_cmds_pending;
         struct xhci_hcd         *xhci;
+        /*
+         * Sometimes the xHC can not process isochronous endpoint ring quickly
+         * enough, and it will miss some isoc tds on the ring and generate
+         * a Missed Service Error Event.
+         * Set skip flag when receive a Missed Service Error Event and
+         * process the missed tds on the endpoint ring.
+         */
+        bool                    skip;
 };
 
 struct xhci_virt_device {