Re: ASoC audio fabric OF bindings RFC. was: Re: ASoC MPC5xxx PSC AC97 audio driver

[David Jander <david.jander@protonic.nl>]

On Mon, 12 Sep 2011 13:48:50 -0600
Grant Likely <grant.likely@secretlab.ca> wrote:

> On Mon, Sep 12, 2011 at 03:52:14PM +0100, Mark Brown wrote:
> > On Mon, Sep 12, 2011 at 03:59:05PM +0200, David Jander wrote:
> > > Mark Brown <broonie@opensource.wolfsonmicro.com> wrote:
> > 
> > > > 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!
> > 
> > I'm not sure I understand what you are talking about.  As I've already
> > said at least once having a *machine* driver which covers multiple
> > machines is absolutely OK.  We already have several such drivers in
> > kernel.
> 
> Yes, a machine driver is quite a sane way to manage the huge range of
> variability of a machine's audio complex.  If it turns out that an SoC
> only ever has one machine driver that handles all possible
> configurations, it still isn't really more complex.  If, however, the
> permutations are sufficiently different to warrant separate driver
> then the groundwork is already established to support it sanely.
> 
> BTW, this isn't a question about "what OF is all about".  It makes
> perfect sense in the OF context to have a node describing how multiple
> devices are aggregated into a single logically composite device.
> 
> Do a machine driver.  It's the right thing to do.

Ok, thanks.

Best regards,

-- 
David Jander
Protonic Holland.