Device trees and audio codecs

[Benjamin Herrenschmidt]

On Sun, 2007-10-21 at 18:12 -0400, Jon Smirl wrote:
> On 10/21/07, Benjamin Herrenschmidt <benh at kernel.crashing.org> wrote:
> >
> > On Sun, 2007-10-21 at 17:33 -0400, Jon Smirl wrote:
> > > > This is one of the i2s channels on the macio.  Dunno why they put
> > > > all those platform-XXX entries in here, (most of) these don't
> > > > logically belong here.
> > >
> > > Actually those platform-XXX entries may be the solution I am looking
> > > for. I can use the generic i2s driver to load a fabric driver as an
> > > ALSA module.
> >
> > Yuck.
> 
> And your alternative is?
> 
> I can use the DTC to load the I2S and codec drivers.
> 
> How do I get the platform specific fabric driver loaded? There is no
> way to load a driver matching on the platform name.

platform-do-XXX is unrelated to that. It's a kind of script in a blob
that is used to toggle various bits, it's plain ugly, totally powermac
specific (the code to handle it is in platform/powermac and I won't make
it generic) and so you don't want it... ever.

For your problem, an option is to do like apple, and have a "sound"
pseudo device which represents the "sound subsystem" of the machine
which cn ahave a compatible property and other bits that you can use to
match your fabric against, and loads the other bits & pieces.

Except that I would put it at the root of the tree.

Ben.