[alsa-devel] ASoC audio fabric OF bindings RFC. was: Re: ASoC MPC5xxx PSC AC97 audio driver

[David Jander]

On Mon, 12 Sep 2011 14:19:24 +0100
Mark Brown <broonie at opensource.wolfsonmicro.com> wrote:

> On Mon, Sep 12, 2011 at 02:55:07PM +0200, David Jander wrote:
> > Mark Brown <broonie at opensource.wolfsonmicro.com> wrote:
> 
> > > Other OSs are actively using device tree.
> 
> > Interesting. I wasn't aware of "actively using". Sure, there's MacOS-X-ppc,
> > IBM AIX, Oracle Solaris.... and I just discovered that Free-/OpenBSD also
> > use them.
> 
> *BSD are the main ones to consider here.
> 
> > > Eliminating board specific code for audio is not a realistic goal, the
> > > configuration of modern audio subsystems is too complex and dynamic.  
> 
> > Why not? How complex could it be in order to not be able to describe it in
> > a Device-Tree in some OS-agnostic way?
> 
> Note the "dynamic" bit - the configuration changes at runtime.
> Describing the hardware for something like a modern smartphone isn't
> particularly useful due to the flexibility, there are too many different
> ways of configuring the system and we need code to acutally take those
> decision.

Ok, but you could still describe the hardwired part of it (Audio muxes,
codecs, busses and physical interfaces). Isn't that what OF is all about?
In our case, its just a simple AC97 codec connected to a simple AC97 bus.
Sounds like total overkill having to write a "fabric driver" for this....
while there are already quite a few that are all 99% the same!

> > > The plan is to push the device trees out of the kernel into a separate
> > > repository.
> 
> > Good idea.... but where should such a repository be hosted?
> 
> Still an open issue.

Seems like its hard to find a vendor- and OS-neutral entity to host this?
OpenBIOS maybe?

Best regards,

-- 
David Jander
Protonic Holland.