From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alan Jenkins Subject: Re: [PATCH] acpi: Avoid dropping rapid hotkey events (or other GPEs) on Asus EeePC Date: Wed, 13 Aug 2008 11:21:10 +0100 Message-ID: <48A2B596.3050401@tuffmail.co.uk> References: <487D23C3.5070301@student.cs.york.ac.uk> <487F58B6.5040309@suse.de> <487F6D2E.2040501@tuffmail.co.uk> <487F772C.1070806@suse.de> <487F9592.1060003@tuffmail.co.uk> <487F9677.4060001@suse.de> <20080812162854.d6907c95.akpm@linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from nf-out-0910.google.com ([64.233.182.185]:58320 "EHLO nf-out-0910.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755053AbYHMKVS (ORCPT ); Wed, 13 Aug 2008 06:21:18 -0400 Received: by nf-out-0910.google.com with SMTP id d3so1044405nfc.21 for ; Wed, 13 Aug 2008 03:21:15 -0700 (PDT) In-Reply-To: <20080812162854.d6907c95.akpm@linux-foundation.org> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Andrew Morton Cc: Alexey Starikovskiy , linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, hmh@hmh.eng.br, Maximilian Engelhardt , linux-stable@vger.kernel.org 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). 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. Thanks Alan