[PATCH] fix cpufreq notifier counting issue

This patch fixes a potential problem with the CPU frequency change
notification code in the EHCI driver.  The code counts the number of
"pre change" and "post change" notifications, and will only take action
on the first "pre change" and the last "post change" notification.  In
the unlikely event that the notifier is registered during a frequency
change, so that the code never gets the pre change notification that
corresponds to a post change notification that it gets, the counter will
be out of sync and the code will not take action at the correct time.

This patch will re-sync the counter if this happens.

This patch is against the 2.6.23-rc3 kernel, plus the patch submitted
and accepted on 8/1 to fix a bug with nVidia controllers
(http://www.mail-archive.com/[email protected]/msg56
523.html), plus the patch I sent a few minutes ago to fix a problem with
VIA EHCI controllers and the cpufreq notifier.

Signed-off-by: Stuart Hayes <[email protected]>

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diff -purN linux-2.6.23-rc3plus_x/drivers/usb/host/ehci-hcd.c linux-2.6.23-rc3plus_y/drivers/usb/host/ehci-hcd.c
--- linux-2.6.23-rc3plus_x/drivers/usb/host/ehci-hcd.c	2007-08-16 15:37:57.000000000 -0500
+++ linux-2.6.23-rc3plus_y/drivers/usb/host/ehci-hcd.c	2007-08-16 15:04:09.000000000 -0500
@@ -299,8 +299,9 @@ static void ehci_cpufreq_unpause (struct
 	unsigned long	flags;
 
 	spin_lock_irqsave(&ehci->lock, flags);
-	if (!--ehci->cpufreq_changing)
-		qh_reactivate_split_intr_qhs(ehci);
+	if (ehci->cpufreq_changing)
+		if (!--ehci->cpufreq_changing)
+			qh_reactivate_split_intr_qhs(ehci);
 	spin_unlock_irqrestore(&ehci->lock, flags);
 }