[BISECTED] snd-hda-intel audio distortion in Linus' current tree

[BISECTED] snd-hda-intel audio distortion in Linus' current tree

[Steven Noonan]

Started having audio problems when trying out the latest tree
(v3.6-rc7-10-g56d27ad). When playing any kind of audio, there was
significant distortion, mostly crackling noise. I'm using a Lenovo
ThinkPad X230 (Panther Point).

I did a git-bisect to locate the problem, and it seems this commit is to
blame:

	c20c5a841cbe47f5b7812b57bd25397497e5fbc0 is the first bad commit
	commit c20c5a841cbe47f5b7812b57bd25397497e5fbc0
	Author: Seth Heasley <seth.heasley@intel.com>
	Date:   Thu Jun 14 14:23:53 2012 -0700

		ALSA: hda_intel: activate COMBO mode for Intel client chipsets
		
		This patch activates the COMBO position_fix for recent Intel client chipsets.
		COMBO mode is the recommended setting for Intel chipsets and eliminates HD
		audio warnings in dmesg.  This patch has been tested on Lynx Point, Panther
		Point, and Cougar Pont.
		
		Signed-off-by: Seth Heasley <seth.heasley@intel.com>
		Signed-off-by: Takashi Iwai <tiwai@suse.de>

It's pretty clear-cut. If I revert this patch, my sound starts
functioning normally again.

Any thoughts on how to proceed here? Can someone revert this, or is
there some testing that I can do?

Here's a pretty-printed bisection log, if needed:

 # good: [28a33cbc] Linux 3.5
 # bad:  [b13bc8dd] Merge tag 'staging-3.6-rc1' of git://git.kernel.or
 # good: [3c4cfade] Merge git://git.kernel.org/pub/scm/linux/kernel/gi
 # bad:  [9fc37779] Merge tag 'usb-3.6-rc1' of git://git.kernel.org/pu
 # bad:  [f14121ab] Merge tag 'dt-for-3.6' of git://sources.calxeda.co
 # good: [d14b7a41] Merge branch 'for-linus' of git://git.kernel.org/p
 # good: [15d47763] Merge branch 'for-3.5' into for-3.6
 # bad:  [dbf7b591] Merge tag 'sound-3.6' of git://git.kernel.org/pub/
 # bad:  [1c76684d] ALSA: hda - add Haswell HDMI codec id
 # bad:  [8b8d654b] ALSA: hda - Move one-time init codes from generic_
 # good: [80c8bfbe] ALSA: HDA: Create phantom jacks for fixed inputs a
 # bad:  [ceaa86ba] ALSA: hda - Remove invalid init verbs for Nvidia 2
 # bad:  [4b6ace9e] ALSA: hda - Add the support for VIA HDMI pin detec
 # bad:  [c20c5a84] ALSA: hda_intel: activate COMBO mode for Intel cli


- Steven

Re: [BISECTED] snd-hda-intel audio distortion in Linus' current tree

[Vincent Cheng]

[Cc: alsa-devel@alsa-project.org; also, please cc: me explicitly as
well, since I'm not subscribed to either list]

On Wed, Sep 26, 2012 at 12:29 AM, Steven Noonan <steven@uplinklabs.net> wrote:
> Started having audio problems when trying out the latest tree
> (v3.6-rc7-10-g56d27ad). When playing any kind of audio, there was
> significant distortion, mostly crackling noise. I'm using a Lenovo
> ThinkPad X230 (Panther Point).
>
> I did a git-bisect to locate the problem, and it seems this commit is to
> blame:
>
>         c20c5a841cbe47f5b7812b57bd25397497e5fbc0 is the first bad commit
>         commit c20c5a841cbe47f5b7812b57bd25397497e5fbc0
>         Author: Seth Heasley <seth.heasley@intel.com>
>         Date:   Thu Jun 14 14:23:53 2012 -0700
>
>                 ALSA: hda_intel: activate COMBO mode for Intel client chipsets
>
>                 This patch activates the COMBO position_fix for recent Intel client chipsets.
>                 COMBO mode is the recommended setting for Intel chipsets and eliminates HD
>                 audio warnings in dmesg.  This patch has been tested on Lynx Point, Panther
>                 Point, and Cougar Pont.
>
>                 Signed-off-by: Seth Heasley <seth.heasley@intel.com>
>                 Signed-off-by: Takashi Iwai <tiwai@suse.de>
>
> It's pretty clear-cut. If I revert this patch, my sound starts
> functioning normally again.
>
> Any thoughts on how to proceed here? Can someone revert this, or is
> there some testing that I can do?
>
> Here's a pretty-printed bisection log, if needed:
>
>  # good: [28a33cbc] Linux 3.5
>  # bad:  [b13bc8dd] Merge tag 'staging-3.6-rc1' of git://git.kernel.or
>  # good: [3c4cfade] Merge git://git.kernel.org/pub/scm/linux/kernel/gi
>  # bad:  [9fc37779] Merge tag 'usb-3.6-rc1' of git://git.kernel.org/pu
>  # bad:  [f14121ab] Merge tag 'dt-for-3.6' of git://sources.calxeda.co
>  # good: [d14b7a41] Merge branch 'for-linus' of git://git.kernel.org/p
>  # good: [15d47763] Merge branch 'for-3.5' into for-3.6
>  # bad:  [dbf7b591] Merge tag 'sound-3.6' of git://git.kernel.org/pub/
>  # bad:  [1c76684d] ALSA: hda - add Haswell HDMI codec id
>  # bad:  [8b8d654b] ALSA: hda - Move one-time init codes from generic_
>  # good: [80c8bfbe] ALSA: HDA: Create phantom jacks for fixed inputs a
>  # bad:  [ceaa86ba] ALSA: hda - Remove invalid init verbs for Nvidia 2
>  # bad:  [4b6ace9e] ALSA: hda - Add the support for VIA HDMI pin detec
>  # bad:  [c20c5a84] ALSA: hda_intel: activate COMBO mode for Intel cli
>
>
> - Steven
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
>
>

I can confirm that I've also hit this bug as well, and that it's still
present in stable 3.6.0. Strangely enough however, this only seems to
affect VLC for me; while playing audio through mplayer or any
gstreamer-based players (Rhythmbox, Totem, etc.), I don't encounter
any audio distortion. Possibly also related to [1]?

A workaround (other than reverting this commit) is to not use COMBO
mode, i.e. load snd-hda-intel with position_fix=2.

Please let me know if any more information is needed.

$ lspci -vvnn | grep -A8 Audio
00:1b.0 Audio device [0403]: Intel Corporation 7 Series/C210 Series
Chipset Family High Definition Audio Controller [8086:1e20] (rev 04)
	Subsystem: Toshiba America Info Systems Device [1179:fb30]
	Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr-
Stepping- SERR- FastB2B- DisINTx+
	Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort-
<TAbort- <MAbort- >SERR- <PERR- INTx-
	Latency: 0, Cache Line Size: 64 bytes
	Interrupt: pin A routed to IRQ 46
	Region 0: Memory at f7310000 (64-bit, non-prefetchable) [size=16K]
	Capabilities: <access denied>
	Kernel driver in use: snd_hda_intel

Machine: Toshiba Satellite P850
Distro: Debian wheezy/sid
ALSA 1.0.25; PulseAudio 2.0

Regards,
Vincent

[1] http://mailman.alsa-project.org/pipermail/alsa-devel/2012-September/055161.html

Re: [BISECTED] snd-hda-intel audio distortion in Linus' current tree

[Pierre Beck]

Hi,

I'd like to confirm this bug exists in 3.6-rc7 32-bit. It seems to occur 
only when opening the audio output, and not with every audio player. MP3 
/ Ogg playback with VLC via Pulseaudio triggers the noise. Xine, Totem 
don't. After about 20 to 40 seconds, it suddenly disappears.

Greetings,

Pierre Beck