1 files changed, 33 insertions, 3 deletions

diff --git a/drivers/usb/host/ehci-sched.c b/drivers/usb/host/ehci-sched.c
index 327437af2122..3ea05936851f 100644
--- a/drivers/usb/host/ehci-sched.c
+++ b/drivers/usb/host/ehci-sched.c
@@ -615,8 +615,19 @@ static int qh_unlink_periodic(struct ehci_hcd *ehci, struct ehci_qh *qh)
 
 static void intr_deschedule (struct ehci_hcd *ehci, struct ehci_qh *qh)
 {
-        unsigned        wait;
-        struct ehci_qh_hw *hw = qh->hw;
+        unsigned                wait;
+        struct ehci_qh_hw       *hw = qh->hw;
+        int                     rc;
+
+        /* If the QH isn't linked then there's nothing we can do
+         * unless we were called during a giveback, in which case
+         * qh_completions() has to deal with it.
+         */
+        if (qh->qh_state != QH_STATE_LINKED) {
+                if (qh->qh_state == QH_STATE_COMPLETING)
+                        qh->needs_rescan = 1;
+                return;
+        }
 
         qh_unlink_periodic (ehci, qh);
 
@@ -636,6 +647,24 @@ static void intr_deschedule (struct ehci_hcd *ehci, struct ehci_qh *qh)
         qh->qh_state = QH_STATE_IDLE;
         hw->hw_next = EHCI_LIST_END(ehci);
         wmb ();
+
+        qh_completions(ehci, qh);
+
+        /* reschedule QH iff another request is queued */
+        if (!list_empty(&qh->qtd_list) &&
+                        HC_IS_RUNNING(ehci_to_hcd(ehci)->state)) {
+                rc = qh_schedule(ehci, qh);
+
+                /* An error here likely indicates handshake failure
+                 * or no space left in the schedule.  Neither fault
+                 * should happen often ...
+                 *
+                 * FIXME kill the now-dysfunctional queued urbs
+                 */
+                if (rc != 0)
+                        ehci_err(ehci, "can't reschedule qh %p, err %d\n",
+                                        qh, rc);
+        }
 }
 
 /*-------------------------------------------------------------------------*/
@@ -2213,7 +2242,8 @@ restart:
                                 type = Q_NEXT_TYPE(ehci, q.qh->hw->hw_next);
                                 q = q.qh->qh_next;
                                 modified = qh_completions (ehci, temp.qh);
-                                if (unlikely (list_empty (&temp.qh->qtd_list)))
+                                if (unlikely(list_empty(&temp.qh->qtd_list) ||
+                                                temp.qh->needs_rescan))
                                         intr_deschedule (ehci, temp.qh);
                                 qh_put (temp.qh);
                                 break;