On Mon, Jul 15, 2013 at 04:53:46PM +0200, Richard Genoud wrote:

2013/7/12 Mark Brown [off-list ref]:

quoted

This isn't going to work with systems which have a variable clock as the
input to the CODEC.  If it's imposing constraints the driver needs to
allow setting the clock to zero as a way of removing constraints (and
any existing drivers should be updated to do this if needed).

Maybe I'm wrong, but I didn't find any system using variable clock
with this codec.

The driver should be written with that possibility in mind even if there
were no users; it only takes a couple of lines of code.

The sam9g20ek (soc/atmel/sam9g20_wm8731.c) is not using a crystal, but
it's using a fixed clock anyway.
But there's soc/pxa/corgi.c and soc/pxa/poodle.c that puzzle me.
They seems to use a crystal, but they are setting a different sysclk
depending on the rate.
That seems wrong, but as I'm a newbie in ASoC...

Note that the CPU is clock master for those - it's going to be
outputting a clock based on the sample rate selected automatically.
These boards would be broken by your change as it stands.