Re: [PATCH] acpi: Avoid dropping rapid hotkey events (or other GPEs) on Asus EeePC

Andrew Morton
2008-08-13T10:47:29Z

On Wed, 13 Aug 2008 11:21:10 +0100 Alan Jenkins <alan-jenkins@tuffmail.co.uk> wrote:

> Andrew Morton wrote:
> > Did this get fixed yet?
> >
> > I have an patch in -mm which I just restored (I had to tempdrop it
> > because the acpi tree was busted for some time). But it seems to be
> > old.
> >
> > http://bugzilla.kernel.org/show_bug.cgi?id=10919 is marked "resolved"
> > but the reporter (Maximilian) seems to think otherwise. 2.6.26.x is,
> > afaik, still unfixed, as is 2.6.27-rc.
> >
> That's correct. I think this specific patch should go in 2.6.27 and
> 2.6.26-stable. No objections have been raised so far.
>
> I still need this patch to make my brightness and volume control keys
> usable in 2.6.27-rc3. (They auto-repeat fast enough to trigger the
> bug). This is true even after applying the latest patches from bug
> 10919 (#25 + #27).
>

Confusing. Please send the patch which you think we should apply.

> I think the 10919 fix makes it harder to reproduce, but it definitely
> still happens. I guess this is because the polling-driven EC
> transactions add 1ms delays between each byte. The slower timings leave
> a window where the buggy behaviour of my EC can make a difference. (It
> has been seen to clear the "pending event" bit after a single event is
> read, despite having more events pending).
>
> There are more serious consequences of this bug. After a while it can
> confuse the EC enough to cause lockups or reboots during boot, or after
> pressing a single hotkey. This bad state is preserved over reboots,
> even into known good kernels. Fortunately the badness clears when power
> is removed for a long enough period. For a while I was worried that
> something had physically burnt out.

Oh gad. And there's no workaround?