[alsa-devel] [PATCH v2 1/2] ASoC: soc-compress: add a config item for soc-compress

[Jie, Yang]

> -----Original Message-----
> From: alsa-devel-bounces at alsa-project.org [mailto:alsa-devel-
> bounces at alsa-project.org] On Behalf Of Mark Brown
> Sent: Wednesday, June 17, 2015 8:24 PM
> To: Koul, Vinod
> Cc: Takashi Iwai; alsa-devel at alsa-project.org; Zhang, Vivian; Babu, Ramesh;
> Girdwood, Liam R
> Subject: Re: [alsa-devel] [PATCH v2 1/2] ASoC: soc-compress: add a config
> item for soc-compress
> 
> On Wed, Jun 17, 2015 at 08:24:48AM +0530, Vinod Koul wrote:
> > On Tue, Jun 16, 2015 at 06:36:22PM +0200, Takashi Iwai wrote:
> 
> Please remember to delete unneeded context from replies.
> 
> > > 	if (cpu_dai->driver->create)
> > > 		ret = cpu_dai->driver->create(rtd, num);
> 
> 
> > > and each driver passes soc_new_compress (or whatever) there.  This
> > > is flexible and can be extended if any new stuff has to be handled.
> > > Even PCM creation or dai widget links can be passed in that form,
> > > too.
> 
> > and the default would be snd_pcm_new so that *most* drivers dont need
> > to add this. Only Intel atom driver should add soc_new_compress() as
> > create ops, hence direct reference so no gaurds required
> 
> > Looks good to me then, Mark you okay with this approach?
> 
> I'm not sure this fully helps.  This will put the reference in the CPU driver
> which if there's sharing with non-compressed DAIs means that any machine
> driver using the platform needs to select the compressed audio code.  It also
> means that we're still in the situation whre if a machine
> *can* support compressed audio it *must* support compressed audio, it's
> not clear to me that people doing this sort of memory optimisation are
> always going to be doing it on hardware that doesn't have the capacity for
> compressed audio (or won't in the future).  But then I don't know exactly
> how much memory is being saved here...

It saves ~12KB memory usage on i386 platform on my side.
 
~Keyon