[alsa-devel] ALSA - No sound on MBA2,1

[Takashi Iwai]

At Wed, 4 Dec 2013 13:42:09 +0100,
Bruno Prémont wrote:
> 
> Hi Takashi,
> 
> On Wed, 04 Dec 2013 12:18:14 +0100 Takashi Iwai wrote:
> > At Wed, 4 Dec 2013 11:47:41 +0100, Bruno Prémont wrote:
> > > On Wed, 04 Dec 2013 08:14:18 +0100 Takashi Iwai wrote:
> > > > At Tue, 3 Dec 2013 22:54:13 +0100, Bruno Prémont wrote:
> > > > > Hi Takashi,
> > > > > 
> > > > > Since I started using Linux on a MBA2,1 I never had sound working.
> > > > > recently searching for some solution to get sound working I saw that
> > > > > some users had sound with 3.2.x kernels and reported it stopped working
> > > > > somewhere between 3.2 and 3.4.
> > > > > 
> > > > > Thus I tried bisecting this and found two steps of losing sound support,
> > > > > a first one being losing sound output on built-in speaker, a second
> > > > > point where sound through headphone jack stopped working.
> > > > > 
> > > > > Even with 3.2 non of the mute options is working (I did not try recording
> > > > > via build-in microphone)
> > > > > 
> > > > > ...
> > > > > 
> > > > > Attached is the output of `alsa-info --with-devices` under current 3.12.2
> > > > > kernel and under 3.2.53.
> > > > > 
> > > > > As this all seems related to quirks being replaced with auto-parsing.
> > > > > Trying to revert the commits on top of 3.12.x looks unworkable.
> > > > > 
> > > > > Is there some extra data I should try to provide or a workaround/fix I
> > > > > could try out? I'm booting in EFI mode using EFI stub (did backport it
> > > > > from 3.3 to 3.2 for bisecting/testing 3.2).
> > > > 
> > > > You seem to be passing model=3stack, and this must break things.
> > > > To be sure, try sound.git tree for-linus branch without any options.
> > > >   git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound.git
> > > 
> > > I tried your branch (with merged rc2 from Linus) and there is still no
> > > sound.
> > > (took some time to test as kernel freezes during boot somewhere in
> > > nouveau, thus me merging in rc2 in the hope of a fix for that)
> > 
> > Thanks.  Could you try the patch below?
> 
> Wow, that patch does a marvelous job!
> 
> Controls listed by alsamixer seem to all work the way they are intended,
> MASTER affects both headphone jack and built-in speaker, muting works
> per-channel as does volume.
> 
> Even the toggle "Headphone/mic jack" seems to perform the operation
> indicated by its name (though I did not try recording yet).
> 
> 
> So the patch is (Reported-and-)Tested-by: Bruno Prémont <bonbons at linux-vserver.org>
> 
> Thanks for your quick response and looking into this!

OK, I'll queue the patch for upstream.

> A rather borderline question/observation:
> When plugging in headphone and the jack is configured as headphone
> built-in speaker gets muted (seems reasonable default, hardware
> triggered).
> Is it possible to have that auto-muting reported in mixer and possibly
> overridden via mixer if wanted (possibly via
> mute-speaker-if-headphone-plugged option)?

You can turn off the auto-mute behavior via "Auto-Mute Mode" mixer
enum.  The Headphone and Speaker volume/mute can be still controlled
manually.  And the jack status can be delivered/read via "Headphone
Jack" control.


Takashi