[alsa-devel] CMI8788/AV200/Oxygen Volume Controls in alsamixer (oxygen_mixer.c:dac_volume_get())

[John Utz]

using exchange webmail today, sorry.

-----Original Message-----
From: Takashi Iwai [mailto:tiwai at suse.de]
Sent: Fri 1/23/2009 5:56 AM
To: Clemens Ladisch
Cc: John Utz; ALSA Developers
Subject: Re: [alsa-devel] CMI8788/AV200/Oxygen Volume Controls in alsamixer (oxygen_mixer.c:dac_volume_get())
 
At Fri, 23 Jan 2009 14:51:31 +0100,
Clemens Ladisch wrote:
> 
> John L. Utz III wrote:
> > It appears to me that these functions are attempting to work on all of 
> > the channels at once instead of just choosing Master, Front, Rear, 
> > Surround, or what have you:
> 
> Yes, the "Master" control is one control with eight channels.
> 
> > this leads to a rather awkward result in alsamixer where there are 5 
> > volume controls called "Master":
> > 
> > < Master >  Master    Master    Master    Master
> > 
> > IMHO, it would be more desirable for them to say:
> > 
> > < Master >  Front     C/LFE     Surround  Rear Surr
> 
> Yes.
> 
> Alsamixer chooses to display an eight-channel control this way.  This
> can be considered a bug in alsamixer.

The current ALSA mixer abstraction splits the multi-channels into
separate paired channels.  But alsamixer can't show the channel name
due to its UI design.  And I guess other mixer apps don't handle them
properly, too (who would care?).

A solution would be make individual control like "Front", and create a
virtual master control.


JU a virtual control in the conf file or in the driver?

Takashi