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

[Liam Girdwood]

On Thu, 2012-01-26 at 14:32 +0000, Mark Brown wrote:
> On Thu, Jan 26, 2012 at 02:27:48PM +0000, Liam Girdwood wrote:
> > On Thu, 2012-01-26 at 14:03 +0000, Mark Brown wrote:
> 
> > >     CPU <-> DSP <-> External
> 
> > >    DSP     External
> > >     ^----v----^
> > >         CPU
> 
> > Fwiw, the OMAP ABE architecture mixes both above diagrams. We are using
> > dynamic PCM for managing all the DAI links and will add in support to
> > use the CODEC <-> CODEC stuff for the loopback DAI interfaces (saving
> > the need to open()), hw_oparams() etc).
> 
> In terms of the data path I think it's pretty much always like the
> second path with the DMA controller owned by Linux driving the data
> between the various components?

Wrt OMAP, the DMA and the ABE can drive data to the component drivers.
Both DMA and ABE only drive data at the request of the CPU (via PCM and
DAI ops).

Regards

Liam