Revisited, audio codec device tree entries.

Grant Likely grant.likely at secretlab.ca
Tue Nov 20 02:42:10 EST 2007


On 11/19/07, Jon Smirl <jonsmirl at gmail.com> wrote:
> On 11/19/07, Timur Tabi <timur at freescale.com> wrote:
> > Jon Smirl wrote:
> >
> > > In the ALSA SOC model the i2s, codec and ac97 drivers are all generic.
> > > A fabric driver tells specifically how a generic codec is wired into
> > > the board. What I haven't been able figure out is how to load the
> > > right fabric driver.
> >
> > Do not use the device tree to load the fabric driver!
>
> If I have a multiplatform kernel with 10 fabric drivers built in, how
> do you decide which one to activate without looking at the device
> tree? Multiplatform kernels are what is causing this problem. If the
> kernel is just for a single platform I can hardwire the fabric driver
> in without looking at the tree.

Simple; instantiate the needed platform_device or of_platform_device
in the board platform code (arch/powerpc/platforms/*).  Then the
driver has something to bind against.

That way the driver's probe() method gets called without having to
traverse the entire tree.

Cheers,
g.

-- 
Grant Likely, B.Sc., P.Eng.
Secret Lab Technologies Ltd.
grant.likely at secretlab.ca
(403) 399-0195



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