Audio codec device tree entries

Grant Likely grant.likely at secretlab.ca
Thu Oct 25 01:16:58 EST 2007


On 10/24/07, Jon Smirl <jonsmirl at gmail.com> wrote:
> On 10/24/07, Timur Tabi <timur at freescale.com> wrote:
> > Jon Smirl wrote:
> > > Is this consensus on how the tree should look?
> > >
> > > There is no attempt to describe the codec connections inside the
> > > device tree.
> >
> > I don't think I agree with that.  The device tree should indicate which codec is
> > connected to which I2S/AC97 device.
>
> What I meant was that there is no attempt to describe how the codec is
> connected to the external world. Those connections are described in
> the fabric driver.
>
> I'm getting conflicting opinions on how the devices should be linked
> into the tree. We should pick one and add it to the documentation.

Two valid methods have been proposed
1. a codec-

> The DTC experts need to tell us which way to make the pointers between
> i2s and i2c for the codec.  Here's a another way it could be done that
> looks more like the ac97 model.

I *really* don't think this is a good idea.  Put the node on the bus
that the device is addressed from.  I2S is the *data* path, not the
*control* path, but you cannot control the codec from there.

Your suggestion only looks more like the AC97 model if you're looking
at the data path.  If you're looking at the control path it looks
completely different.  The device tree convention is to orient around
the control path.

g.

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



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