On 17-Apr-06, at 3:05 PM, Brian Buhrow wrote:
> 	Also, it occurs to me that for those cards which support multiple
> voices, a driver could instantiate multiple audio devices, i.e.  
> audio0,
> audio1, etc.  I'm thinking of cards like the Creative Labs Sound  
> Blaster
> Live!  Then, as long as you point user processes at different audio
> devices, sharing should work fine.  (I'm assuming that mixerctl  
> settings
> could be used to properly balance the two concurrent sounds for each
> device.)

The esa(4) driver already supports this -- hardware mixing of 4  
independent playback channels by calling audio_attach_mi() four  
times. To enable support, set 'options ESA_NUM_VOICES=4' in your  
kernel config.

I think we have other hardware drivers that support similar  
behaviour, but I haven't tested any others.

Cheers,
Jared