From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Henningsson Subject: Re: [PATCH] ALSA: hda - Disable runtime PM on LynxPoint(-LP) controllers Date: Wed, 20 Nov 2013 14:35:09 +0100 Message-ID: <528CBA8D.8020907@canonical.com> References: <528C78D2.6020207@canonical.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from youngberry.canonical.com (youngberry.canonical.com [91.189.89.112]) by alsa0.perex.cz (Postfix) with ESMTP id F11FE2616E1 for ; Wed, 20 Nov 2013 14:35:10 +0100 (CET) In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org To: Takashi Iwai Cc: "Lin, Mengdong" , alsa-devel@alsa-project.org List-Id: alsa-devel@alsa-project.org On 11/20/2013 02:32 PM, Takashi Iwai wrote: > At Wed, 20 Nov 2013 13:05:23 +0100, > Takashi Iwai wrote: >> >> At Wed, 20 Nov 2013 09:54:42 +0100, >> David Henningsson wrote: >>> >>> (Adding Mengdong to cc) >>> >>> On 11/19/2013 05:51 PM, Takashi Iwai wrote: >>>> We got bug reports of the stalled HD-audio, typically after S3 or S4, >>>> and it turned out that they seemed triggered by runtime PM on Lynx >>>> Point and Lynx Point-LP controllers. As there is no way to recover >>>> properly from the stalled controller, it's safer to disable the >>>> runtime PM support on these chips for now. >>> >>> Oh, this is a bit sad news. Have you talked to Intel about it? >>> >>> Anyway, I saw something similar a while ago, but never with access to >>> the hardware, and then it was difficult to reproduce for the person on >>> the other side. Nevertheless, when I read through the PM code I found >>> that the GCTL register was sometimes accessed with readb (although it is >>> a 32 bit register), so I wrote a patch for that, but the testing results >>> of this patch were a bit inconclusive, so I never upstreamed it. >>> >>> Anyway, I'm attaching the draft patch. Do you think it could be related? >> >> It didn't change the behavior although the change looks good. It looks good indeed, but it's always scary to do subtle changes without testing on all the 50+ controllers we support...do you think I should submit a proper patch for it? >> >> After a long debugging session in this morning, I finally nailed >> down. This was the fault in the sound driver after all, shamefully :) >> >> The fix patch is below. >> >> The code needs a bit clean up, and I have it, but will apply this for >> 3.14. >> >> >> Takashi >> >> === >> >> From: Takashi Iwai >> Subject: [PATCH 1/2] ALSA: hda - Fix unbalanced runtime PM notification at >> resume > > BTW, it's marked as 1/2 just because of the clean up patch I mentioned > above. Only this one is needed for now. Ok, thanks for the clarification, and glad you finally found it! And so are you I guess :-) -- David Henningsson, Canonical Ltd. https://launchpad.net/~diwic