2010-11-25 18:57:35

by Kyle McMartin

[permalink] [raw]
Subject: [PATCH] ALSA: patch_realtek: handle unset external amp bits

From: Kyle McMartin <[email protected]>

Commit ef5dbbcc removes the default initialization of init_amp to
ALC_INIT_DEFAULT, with the justification that it should be set by
alc_subsystem_id, which contains a switch case:

tmp = (ass & 0x38) >> 3; /* external Amp control */
switch (tmp) {
case 1:
...
case 5:
}

Which handles values 1,3,7 for GPIOs, or 5 to set _DEFAULT.

But... what if it's 0? :)

I got a bug report this morning from a user whose sound had broken
between 2.6.34 and 2.6.35, and I bisected it down to this commit.

[ 32.366183] ALSA sound/pci/hda/patch_realtek.c:1374: realtek: Enabling
init ASM_ID=0x8a05 CODEC_ID=10ec0888

(0x8a05 & 0x38) >> 3 = 0;

But otherwise the SKU looks fine (since if I revert that commit, it
seems to work correctly.)

I think the best thing to do would be to either restore the 'redundant'
default initialization, or quirk it.

https://bugzilla.redhat.com/show_bug.cgi?id=657388

Signed-off-by: Kyle McMartin <[email protected]>
---
Revert "ALSA: hda - Remove superfluous external amp setup for ALC888"

This reverts commit ef5dbbccbbfa7d2211fa8efcc095a9f4a7912dda.

diff --git a/sound/pci/hda/patch_realtek.c b/sound/pci/hda/patch_realtek.c
index 76c4968..b6ba1d5 100644
--- a/sound/pci/hda/patch_realtek.c
+++ b/sound/pci/hda/patch_realtek.c
@@ -10604,6 +10604,9 @@ static int patch_alc882(struct hda_codec *codec)
spec->stream_digital_playback = &alc882_pcm_digital_playback;
spec->stream_digital_capture = &alc882_pcm_digital_capture;

+ if (codec->vendor_id == 0x10ec0888)
+ spec->init_amp = ALC_INIT_DEFAULT; /* always initialize */
+
if (!spec->adc_nids && spec->input_mux) {
int i, j;
spec->num_adc_nids = 0;


2010-11-26 05:51:15

by Takashi Iwai

[permalink] [raw]
Subject: Re: [PATCH] ALSA: patch_realtek: handle unset external amp bits

At Thu, 25 Nov 2010 13:57:30 -0500,
Kyle McMartin wrote:
>
> From: Kyle McMartin <[email protected]>
>
> Commit ef5dbbcc removes the default initialization of init_amp to
> ALC_INIT_DEFAULT, with the justification that it should be set by
> alc_subsystem_id, which contains a switch case:
>
> tmp = (ass & 0x38) >> 3; /* external Amp control */
> switch (tmp) {
> case 1:
> ...
> case 5:
> }
>
> Which handles values 1,3,7 for GPIOs, or 5 to set _DEFAULT.
>
> But... what if it's 0? :)
>
> I got a bug report this morning from a user whose sound had broken
> between 2.6.34 and 2.6.35, and I bisected it down to this commit.
>
> [ 32.366183] ALSA sound/pci/hda/patch_realtek.c:1374: realtek: Enabling
> init ASM_ID=0x8a05 CODEC_ID=10ec0888
>
> (0x8a05 & 0x38) >> 3 = 0;
>
> But otherwise the SKU looks fine (since if I revert that commit, it
> seems to work correctly.)
>
> I think the best thing to do would be to either restore the 'redundant'
> default initialization, or quirk it.
>
> https://bugzilla.redhat.com/show_bug.cgi?id=657388
>
> Signed-off-by: Kyle McMartin <[email protected]>

How about setting default to ALC_INIT_DEFAULT instead like the patch
below? This is safer than forcing ALC_INIT_DEFAULT to all, I
suppose.


thanks,

Takashi

---
diff --git a/sound/pci/hda/patch_realtek.c b/sound/pci/hda/patch_realtek.c
index 81a2a49..886d7c7 100644
--- a/sound/pci/hda/patch_realtek.c
+++ b/sound/pci/hda/patch_realtek.c
@@ -1614,6 +1614,7 @@ do_sku:
spec->init_amp = ALC_INIT_GPIO3;
break;
case 5:
+ default:
spec->init_amp = ALC_INIT_DEFAULT;
break;
}

2010-11-26 13:29:26

by Kyle McMartin

[permalink] [raw]
Subject: Re: [PATCH] ALSA: patch_realtek: handle unset external amp bits

On Fri, Nov 26, 2010 at 06:51:11AM +0100, Takashi Iwai wrote:
> How about setting default to ALC_INIT_DEFAULT instead like the patch
> below? This is safer than forcing ALC_INIT_DEFAULT to all, I
> suppose.
>

As I understand the code, that should work fine. I'll build a new kernel
for my tester to confirm, I suspect it will though. :)

Thanks!
--Kyle

2010-11-26 14:04:15

by Takashi Iwai

[permalink] [raw]
Subject: Re: [PATCH] ALSA: patch_realtek: handle unset external amp bits

At Fri, 26 Nov 2010 08:29:22 -0500,
Kyle McMartin wrote:
>
> On Fri, Nov 26, 2010 at 06:51:11AM +0100, Takashi Iwai wrote:
> > How about setting default to ALC_INIT_DEFAULT instead like the patch
> > below? This is safer than forcing ALC_INIT_DEFAULT to all, I
> > suppose.
> >
>
> As I understand the code, that should work fine. I'll build a new kernel
> for my tester to confirm, I suspect it will though. :)

Thanks!


Takashi

2010-11-26 16:07:19

by Kyle McMartin

[permalink] [raw]
Subject: Re: [PATCH] ALSA: patch_realtek: handle unset external amp bits

On Fri, Nov 26, 2010 at 03:04:13PM +0100, Takashi Iwai wrote:
> > As I understand the code, that should work fine. I'll build a new kernel
> > for my tester to confirm, I suspect it will though. :)
>
> Thanks!
>

Tester confirms audio works after the patch. Thanks!

2010-11-26 16:18:30

by Takashi Iwai

[permalink] [raw]
Subject: Re: [PATCH] ALSA: patch_realtek: handle unset external amp bits

At Fri, 26 Nov 2010 11:07:14 -0500,
Kyle McMartin wrote:
>
> On Fri, Nov 26, 2010 at 03:04:13PM +0100, Takashi Iwai wrote:
> > > As I understand the code, that should work fine. I'll build a new kernel
> > > for my tester to confirm, I suspect it will though. :)
> >
> > Thanks!
> >
>
> Tester confirms audio works after the patch. Thanks!

Thanks, now applied it.
I'm going to send a pull request to Linus tomorrow.


Takashi