[alsa-devel] soc-dsp programming model for loopbacks

[Liam Girdwood]

On Wed, 2012-01-25 at 17:20 +0000, Mark Brown wrote:
> On Wed, Jan 25, 2012 at 05:12:25PM +0000, Liam Girdwood wrote:
> > On Tue, 2012-01-24 at 22:00 +0000, Mark Brown wrote:
> 
> > > Note that the use of soc-dsp isn't required for on-SoC DSPs - it really
> > > depends on how the hardware looks.  If the DSP external format is very
> > > strongly tied to the format used to DMA to and from main memory (or
> > > other interfaces) then soc-dsp is what you need, if the DSP is able to
> > > rewrite formats more flexibly then it should be more direct to model it
> > > as a CODEC device with whatever number of DAIs and routing between them.
> 
> > It's also needed if your DSP cant control or configure any of your host
> > CPU DAI hardware controllers that it needs to physically use to route
> > audio data.
> 
> Depends how they're allocated - the DSP driver can always do the
> management on behalf of the DSP firmware if the hardware is structured
> in a way that makes that make sense (for example, if the CPU never talks
> to the outside world directly).

Wouldn't that either mean the DSP driver (re)implements some of the CPU
DAI driver operations OR the DSP driver calling the CPU DAI driver ops
directly ? 

Regards

Liam