[alsa-devel] Question about sound channel

[Takashi Iwai]

At Tue, 20 Mar 2012 22:45:18 -0700 (PDT),
Kuninori Morimoto wrote:
> 
> 
> Hi ALSA ML
> 
> I have question about sound channel.
> If input sound was MONO (= 1ch), but codec supports I2S (= 2ch) only,
> How to output sound ?
> What should the driver do in this case ?

The driver should expose its capability just as is, i.e. in your case,
support only two channels.  Then alsa-lib plugin will do the necessary
thing in user-space, such as channel expansions, format conversions,
rate conversions, etc.


Takashi