[alsa-devel] using 'type softvol' in a card conf file in /usr/share/alsa/cards, am i doing this right?

[Takashi Iwai]

At Mon, 4 Jun 2007 15:23:06 -0700,
John L. Utz III wrote:
> 
> Hello;
> 
> I am working with an CMEDIA 8738-MC6 and i am trying to gain control of
> the second DAC by way of softvolume. but i seem to not be succeeding
> because my application cant find my 'Rear' control, am i doing this
> correctly?
> 
> the original /usr/share/alsa/cards/CMI8738-MC6.conf
> 
> CMI8738-MC6.pcm.rear.0 {
> 	@args [ CARD ]
> 	@args.CARD {
> 		type string
> 	}
> 	type hw
> 	card $CARD
> 	device 1
> }
> 
> i have modified it to look thusly: notice that the type is now softvol
> and the original hardware description is encapsulated in slave.pcm
> 
> # 2nd DAC
> CMI8738-MC6.pcm.rear.0 {
>         @args [ CARD ]
>         @args.CARD {
>                 type string
>         }
>         type softvol
>         slave.pcm {
>                 type hw
>                 card $CARD
>                 device 1
>         }
>         control {
>                 name "Rear Playback Volume"
>                 card $CARD
>         }
> }
> 
> Shouldnt i now be able to see 'Rear Playback Volume' in the output of
> amixer controls ??

The control is created first when you access this defined PCM.
Try to open "rear" PCM first, then check amixer.

Once after a user-defined control is created, it can be saved/restored
via alsactl save/restore command.


Takashi