diff -uNrp linux-source-2.6.28/drivers/usb/host/ehci.h linux-source-2.6.28.new/drivers/usb/host/ehci.h
--- linux-source-2.6.28/drivers/usb/host/ehci.h	2008-12-25 00:26:37.000000000 +0100
+++ linux-source-2.6.28.new/drivers/usb/host/ehci.h	2009-02-02 00:20:50.000000000 +0100
@@ -86,6 +86,9 @@ struct ehci_hcd {			/* one per controlle
 	union ehci_shadow	*pshadow;	/* mirror hw periodic table */
 	int			next_uframe;	/* scan periodic, start here */
 	unsigned		periodic_sched;	/* periodic activity count */
+	struct list_head        cached_itd_list; /* list of itds completed
+			while frame hadn't yet elapsed */
+	unsigned                clock_frame;
 
 	/* per root hub port */
 	unsigned long		reset_done [EHCI_MAX_ROOT_PORTS];
@@ -210,6 +213,8 @@ timer_action (struct ehci_hcd *ehci, enu
 	}
 }
 
+static void free_cached_itd_list(struct ehci_hcd *ehci);
+
 /*-------------------------------------------------------------------------*/
 
 #include <linux/usb/ehci_def.h>
diff -uNrp linux-source-2.6.28/drivers/usb/host/ehci-hcd.c linux-source-2.6.28.new/drivers/usb/host/ehci-hcd.c
--- linux-source-2.6.28/drivers/usb/host/ehci-hcd.c	2008-12-25 00:26:37.000000000 +0100
+++ linux-source-2.6.28.new/drivers/usb/host/ehci-hcd.c	2009-02-02 00:18:52.000000000 +0100
@@ -485,6 +485,7 @@ static int ehci_init(struct usb_hcd *hcd
 	 * periodic_size can shrink by USBCMD update if hcc_params allows.
 	 */
 	ehci->periodic_size = DEFAULT_I_TDPS;
+	INIT_LIST_HEAD(&ehci->cached_itd_list);
 	if ((retval = ehci_mem_init(ehci, GFP_KERNEL)) < 0)
 		return retval;
 
@@ -497,6 +498,7 @@ static int ehci_init(struct usb_hcd *hcd
 
 	ehci->reclaim = NULL;
 	ehci->next_uframe = -1;
+	ehci->clock_frame = -1;
 
 	/*
 	 * dedicate a qh for the async ring head, since we couldn't unlink
diff -uNrp linux-source-2.6.28/drivers/usb/host/ehci-mem.c linux-source-2.6.28.new/drivers/usb/host/ehci-mem.c
--- linux-source-2.6.28/drivers/usb/host/ehci-mem.c	2008-12-25 00:26:37.000000000 +0100
+++ linux-source-2.6.28.new/drivers/usb/host/ehci-mem.c	2009-02-02 00:22:16.000000000 +0100
@@ -128,6 +128,7 @@ static inline void qh_put (struct ehci_q
 
 static void ehci_mem_cleanup (struct ehci_hcd *ehci)
 {
+	free_cached_itd_list(ehci);
 	if (ehci->async)
 		qh_put (ehci->async);
 	ehci->async = NULL;
diff -uNrp linux-source-2.6.28/drivers/usb/host/ehci-sched.c linux-source-2.6.28.new/drivers/usb/host/ehci-sched.c
--- linux-source-2.6.28/drivers/usb/host/ehci-sched.c	2008-12-25 00:26:37.000000000 +0100
+++ linux-source-2.6.28.new/drivers/usb/host/ehci-sched.c	2009-02-02 00:37:23.000000000 +0100
@@ -1004,7 +1004,8 @@ iso_stream_put(struct ehci_hcd *ehci, st
 
 		is_in = (stream->bEndpointAddress & USB_DIR_IN) ? 0x10 : 0;
 		stream->bEndpointAddress &= 0x0f;
-		stream->ep->hcpriv = NULL;
+		if (stream->ep)
+			stream->ep->hcpriv = NULL;
 
 		if (stream->rescheduled) {
 			ehci_info (ehci, "ep%d%s-iso rescheduled "
@@ -1653,14 +1654,26 @@ itd_complete (
 			(stream->bEndpointAddress & USB_DIR_IN) ? "in" : "out");
 	}
 	iso_stream_put (ehci, stream);
-	/* OK to recycle this ITD now that its completion callback ran. */
+
 done:
 	usb_put_urb(urb);
 	itd->urb = NULL;
-	itd->stream = NULL;
-	list_move(&itd->itd_list, &stream->free_list);
-	iso_stream_put(ehci, stream);
-
+	if (ehci->clock_frame != itd->frame || itd->index[7] != -1) {
+		/* OK to recycle this ITD now. */
+		itd->stream = NULL;
+		list_move(&itd->itd_list, &stream->free_list);
+		iso_stream_put(ehci, stream);
+	} else {
+		/* HW might still start transactions based on this ITD.
+		   If its content changed that is. Move it to a safe place. */
+		list_move(&itd->itd_list, &ehci->cached_itd_list);
+		if (stream->refcount == 2) {
+			/* If iso_stream_put() would be called here, stream
+			   would be freed. Prevent stream's reusage instead. */
+			stream->ep->hcpriv = NULL;
+			stream->ep = NULL;
+		}
+	}
 	return retval;
 }
 
@@ -2101,6 +2114,20 @@ done:
 
 /*-------------------------------------------------------------------------*/
 
+static void free_cached_itd_list(struct ehci_hcd *ehci)
+{
+       struct ehci_itd *itd, *n;
+
+       list_for_each_entry_safe(itd, n, &ehci->cached_itd_list, itd_list) {
+               struct ehci_iso_stream  *stream = itd->stream;
+               itd->stream = NULL;
+               list_move(&itd->itd_list, &stream->free_list);
+               iso_stream_put(ehci, stream);
+       }
+}
+
+/*-------------------------------------------------------------------------*/
+
 static void
 scan_periodic (struct ehci_hcd *ehci)
 {
@@ -2115,10 +2142,17 @@ scan_periodic (struct ehci_hcd *ehci)
 	 * Touches as few pages as possible:  cache-friendly.
 	 */
 	now_uframe = ehci->next_uframe;
-	if (HC_IS_RUNNING (ehci_to_hcd(ehci)->state))
+	if (HC_IS_RUNNING(ehci_to_hcd(ehci)->state)) {
 		clock = ehci_readl(ehci, &ehci->regs->frame_index);
-	else
+		clock_frame = (clock >> 3) % ehci->periodic_size;
+        } else  {
 		clock = now_uframe + mod - 1;
+		clock_frame = -1;
+	}
+	if (ehci->clock_frame != clock_frame) {
+		free_cached_itd_list(ehci);
+		ehci->clock_frame = clock_frame;
+	}
 	clock %= mod;
 	clock_frame = clock >> 3;
 
@@ -2277,6 +2311,10 @@ restart:
 			/* rescan the rest of this frame, then ... */
 			clock = now;
 			clock_frame = clock >> 3;
+			if (ehci->clock_frame != clock_frame) {
+				free_cached_itd_list(ehci);
+				ehci->clock_frame = clock_frame;
+			}
 		} else {
 			now_uframe++;
 			now_uframe %= mod;