[alsa-devel] EeePC 1005PE microphone is "stereo only", silent in mono

[Takashi Iwai]

At Wed, 03 Aug 2011 10:56:01 +0200,
Paul Menzel wrote:
> 
> Am Mittwoch, den 03.08.2011, 08:26 +0200 schrieb Takashi Iwai:
> 
> […]
> 
> > From: Takashi Iwai <tiwai at suse.de>
> > Subject: [PATCH] ALSA: hda - Fix digital-mic mono recording on ASUS eeePC
> 
> The official spelling seems to be Eee PC [1].
> 
> > The digital-mic unit on ASUS eeePC gives PDM signals instead of the normal
> 
> Dito.
> 
> > stereo PCM, thus you can't record a mono stream from the stereo stream as
> > is; the summing the stereo signal results in almost zero level, and you'll
> 
> Should »the summing« be »in summary«?

Eh, no, I meant the "summed" signal.

> 
> > hear only noise.
> > 
> > As a workaround, use ALC269-specific COEF to manipulate the dmic route
> > for mono, like used for ALC271x.  Since this is implemented as a fix-up
> > and the auto-parser works fine for eeePC, the patch drops the model
> > quirk entries for them, too.
> 
> So as a consequence everyone using `model=auto` can drop that from
> `/etc/modprobe.d/`?
> 
> I do not know how high the regression chance might be, but if there is
> any, maybe split the patch and write all models in the commit summary
> 
>         ALSA: hda - Use auto parser for ASUS UX50, Eeepc P901, Eeepc S101 and P1005HA
> 
> for people looking through the commit log.

Sounds reasonable.  Done now.


thanks,

Takashi