re : 3.2-rc2 regression due to commit "USB: EHCI: fix HUB TTscheduling issue with iso transfer" 811c926c

From: matthieu castet
Date: Sat Nov 26 2011 - 17:13:23 EST


Hi,

could you try the following patch ?

It seems there is a flow in the error condition.


Matthieu


diff --git a/drivers/usb/host/ehci-sched.c b/drivers/usb/host/ehci-sched.c
index 56a3203..464b451 100644
--- a/drivers/usb/host/ehci-sched.c
+++ b/drivers/usb/host/ehci-sched.c
@@ -1475,6 +1475,7 @@ iso_stream_schedule (
* jump until after the queue is primed.
*/
else {
+ int done = 0;
start = SCHEDULE_SLOP + (now & ~0x07);

/* NOTE: assumes URB_ISO_ASAP, to limit complexity/bugs */
@@ -1491,19 +1492,23 @@ iso_stream_schedule (
/* check schedule: enough space? */
if (stream->highspeed) {
if (itd_slot_ok(ehci, mod, start,
- stream->usecs, period))
+ stream->usecs, period)) {
+ done = 1;
break;
+ }
} else {
if ((start % 8) >= 6)
continue;
if (sitd_slot_ok(ehci, mod, stream,
- start, sched, period))
+ start, sched, period)) {
+ done = 1;
break;
+ }
}
} while (start > next);

/* no room in the schedule */
- if (start == next) {
+ if (!done) {
ehci_dbg(ehci, "iso resched full %p (now %d max %d)\n",
urb, now, now + mod);
status = -ENOSPC;
--
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