diff --git a/drivers/usb/host/ehci-sched.c b/drivers/usb/host/ehci-sched.c
index 83be03f..0beddf6 100644
--- a/drivers/usb/host/ehci-sched.c
+++ b/drivers/usb/host/ehci-sched.c
@@ -1370,6 +1370,21 @@ sitd_slot_ok (
 	return 1;
 }
 
+/* rebase in case of underun with ISO_ASAP together */
+static void iso_stream_rebase(struct ehci_hcd *ehci,
+		struct ehci_iso_stream	*stream, u32 mod)
+{
+	u32 i;
+
+	if (ehci->last_base == -1)
+		return;
+
+	for (i = ehci->last_base; i != ehci->last_iso_frame;
+			i = (i + 1) & (mod - 1))
+		if (stream->next_uframe & (mod - 1) == i & (mod - 1))
+			ehci->last_iso_frame = i;
+}
+
 /*
  * This scheduler plans almost as far into the future as it has actual
  * periodic schedule slots.  (Affected by TUNE_FLS, which defaults to
@@ -1409,7 +1424,9 @@ iso_stream_schedule (
 	 * (irq delays etc).  If there are, the behavior depends on
 	 * whether URB_ISO_ASAP is set.
 	 */
-	if (likely (!list_empty (&stream->td_list))) {
+	if (likely (!list_empty (&stream->td_list) ||
+				hcd_complete_in_progress(
+				ehci_to_hcd(ehci), urb))) {
 
 		/* Take the isochronous scheduling threshold into account */
 		if (ehci->i_thresh)
@@ -1417,6 +1434,10 @@ iso_stream_schedule (
 		else
 			next = (now + 2 + 7) & ~0x07;	/* full frame cache */
 
+		if (list_empty(&stream->td_list) &&
+				(urb->transfer_flags & URB_ISO_ASAP))
+			iso_stream_rebase(ehci, stream, mod);
+
 		/*
 		 * Use ehci->last_iso_frame as the base.  There can't be any
 		 * TDs scheduled for earlier than that.
@@ -1517,6 +1538,7 @@ iso_stream_schedule (
 	/* Make sure scan_isoc() sees these */
 	if (ehci->isoc_count == 0)
 		ehci->last_iso_frame = now >> 3;
+	ehci->last_base = -1;
 	return 0;
 
  fail:
@@ -2255,6 +2277,9 @@ static void scan_isoc(struct ehci_hcd *ehci)
 	}
 	ehci->now_frame = now_frame;
 
+	if (ehci->last_base == -1)
+		ehci->last_base = ehci->last_iso_frame;
+
 	frame = ehci->last_iso_frame;
 	for (;;) {
 		union ehci_shadow	q, *q_p;