1 files changed, 14 insertions, 5 deletions

diff --git a/drivers/usb/host/uhci-q.c b/drivers/usb/host/uhci-q.c
index e5d60d5b105a..60379b17bbc1 100644
--- a/drivers/usb/host/uhci-q.c
+++ b/drivers/usb/host/uhci-q.c
@@ -1271,7 +1271,8 @@ static int uhci_submit_isochronous(struct uhci_hcd *uhci, struct urb *urb,
         } else if (qh->period != urb->interval) {
                 return -EINVAL;         /* Can't change the period */
 
-        } else {        /* Pick up where the last URB leaves off */
+        } else {
+                /* Find the next unused frame */
                 if (list_empty(&qh->queue)) {
                         frame = qh->iso_frame;
                 } else {
@@ -1283,10 +1284,18 @@ static int uhci_submit_isochronous(struct uhci_hcd *uhci, struct urb *urb,
                                         lurb->number_of_packets *
                                         lurb->interval;
                 }
-                if (urb->transfer_flags & URB_ISO_ASAP)
-                        urb->start_frame = frame;
-                else if (urb->start_frame != frame)
-                        return -EINVAL;
+                if (urb->transfer_flags & URB_ISO_ASAP) {
+                        /* Skip some frames if necessary to insure
+                         * the start frame is in the future.
+                         */
+                        uhci_get_current_frame_number(uhci);
+                        if (uhci_frame_before_eq(frame, uhci->frame_number)) {
+                                frame = uhci->frame_number + 1;
+                                frame += ((qh->phase - frame) &
+                                        (qh->period - 1));
+                        }
+                }       /* Otherwise pick up where the last URB leaves off */
+                urb->start_frame = frame;
         }
 
         /* Make sure we won't have to go too far into the future */