Re: External USB2 HDD affects speed hda

From: David Brownell
Date: Fri Sep 16 2005 - 21:37:23 EST


> Hi David. Has there been any progress on this issue?
>
> (thread at http://marc.theaimsgroup.com/?t=111749614000002&r=1&w=2)

Taking a look at that, I found one case that _might_ explain it. That
scenario could crop more (or less) based on loads and timings, and I've
suspected that the VIA chips have significantly different timings for
certain things. This patch handles that case differently, just expecting
the unlink completion code (later) to restart the schedule.

I sanity tested this, but that's all.

- Dave

--- g26.orig/drivers/usb/host/ehci-q.c 2005-09-12 17:58:21.000000000 -0700
+++ g26/drivers/usb/host/ehci-q.c 2005-09-14 10:26:07.000000000 -0700
@@ -781,7 +781,7 @@ static void qh_link_async (struct ehci_h
/* (re)start the async schedule? */
head = ehci->async;
timer_action_done (ehci, TIMER_ASYNC_OFF);
- if (!head->qh_next.qh) {
+ if (!head->qh_next.qh && !ehci->reclaim) {
u32 cmd = readl (&ehci->regs->command);

if (!(cmd & CMD_ASE)) {
-
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