[alsa-devel] alsactl adds volume controls?

[Takashi Iwai]

At Mon, 04 Oct 2010 14:26:56 +0200,
Clemens Ladisch wrote:
> 
> Colin Guthrie wrote:
> > 'Twas brillig, and Clemens Ladisch at 01/10/10 10:02 did gyre and gimble:
> > > |   Amp-Out caps: N/A
> > > 
> > > Is this still "N/A" when you try again?
> > 
> > Yeah, I've run the script a few times and this has always been N/A.
> 
> No problem; according to the datasheet, this node does not have amp-out
> caps, and the driver has to read them from the default node instead.

Yes, "N/A" is a valid information here.  The default amp-out cap is
taken in this case.

> But this appears to work correctly, or you wouldn't have any control for
> this node.
> 
> > As a more general question, how is the quirk for fixing the 0==mute
> > thing added? Is it a kernel patch or some tweak in the /usr/share/alsa/
> > tree (i.e. alsalib based quirk?)
> 
> At the moment, no working mechanism for changing control information in
> user space exists.  (But it should be possible to make the "default"
> control device some new plugin that redirects to the "hw" device while
> changing some entries.)

Right, it'd be tricky, so I don't think we go for this.
Adding a quirk to the driver would be much simpler in such a case.


Takashi