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

John Utz John.Utz at dmx.com
Fri Jan 23 20:07:56 CET 2009

Sorry in advance about how i write mail today, i am working from home so i have to use exchange webmail.

-----Original Message-----
From: Clemens Ladisch [mailto:clemens at ladisch.de]
Sent: Fri 1/23/2009 5:51 AM
To: John Utz
Cc: ALSA Developers
Subject: Re: [alsa-devel] CMI8788/AV200/Oxygen Volume Controls in alsamixer (oxygen_mixer.c:dac_volume_get())
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.

JU Argh, yet another implementation strategy from a vendor. Too bad, but remember, this is why we use ALSA now instead of OSS. :-)

> 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


Alsamixer chooses to display an eight-channel control this way.  This
can be considered a bug in alsamixer.

JU It *could*, but that's probably an impractical perspective. zillions of other drivers present this data in the way that amixer, alsamixer and many other mixers expect. 

Best regards,

More information about the Alsa-devel mailing list