From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965957AbbD1NFX (ORCPT ); Tue, 28 Apr 2015 09:05:23 -0400 Received: from cantor2.suse.de ([195.135.220.15]:44881 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965542AbbD1NFV (ORCPT ); Tue, 28 Apr 2015 09:05:21 -0400 Date: Tue, 28 Apr 2015 15:05:20 +0200 Message-ID: From: Takashi Iwai To: Jonathan McDowell Cc: alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org Subject: Re: Audio crackles with 4.1-rc1 In-Reply-To: <20150428123518.GU10148@earth.li> References: <20150428112156.GQ10148@earth.li> <20150428123518.GU10148@earth.li> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI/1.14.6 (Maruoka) FLIM/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL/10.8 Emacs/24.4 (x86_64-suse-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org At Tue, 28 Apr 2015 13:35:18 +0100, Jonathan McDowell wrote: > > On Tue, Apr 28, 2015 at 02:00:17PM +0200, Takashi Iwai wrote: > > At Tue, 28 Apr 2015 12:21:57 +0100, > > Jonathan McDowell wrote: > > > > > > Having upgraded to 4.1-rc1 from 4.0 I'm now hearing audio crackles at > > > regular intervals. I'm fairly sure this is due to the HDA power save as > > > once audio is playing things are fine, it's just when starting to play > > > audio that I hear the crackle. > > > > > > System is a Dell Latitude E7240. I haven't tried a bisect yet but will > > > attempt to find some time to do so in the next few days. It looks like > > > there have been some changes in sound/hda/ between 4.0 + 4.1-rc1 so I'll > > > concentrate on those first. > > > > > There are lots of code changes and enhancements wrt power saving in > > 4.1, and bisection won't help so much, I'm afraid. > > > > First off, check the device status while you hear crackles. > > Is the codec in runtime suspend (aka power save)? This can be seen in > > /sys/bus/hdaudio/devices/*/power/runtime_status. Then check the > > runtime status of the controller, too, found in > > /sys/class/sound/card?/device/power/runtime_status. > > The cracking is definitely happening with the transition from suspended > to active: > > /sys/class/sound/card0/device/power/runtime_status:suspended > /sys/class/sound/card1/device/power/runtime_status:active > /sys/bus/hdaudio/devices/hdaudioC0D0/power/runtime_status:suspended > /sys/bus/hdaudio/devices/hdaudioC1D0/power/runtime_status:active > > card1 + C1D0 were suspended, I hit delete in a terminal to force a > terminal bell, got the crackle and the state changed to active as above. Ah, so it's a click noise that happens only once per runtime PM transition? I thought it were constant crackling noises from your description ("regular intervals"). In anyway, please give alsa-info.sh output on both 4.0 and 4.1. Takashi