[alsa-devel] [PATCH v2 1/3] ASoC: es8316: judge PCM rate at later timing

Mark Brown broonie at kernel.org
Tue Sep 3 13:11:38 CEST 2019


On Tue, Sep 03, 2019 at 04:19:10AM +0900, Katsuhiro Suzuki wrote:
> On 2019/09/02 21:02, Mark Brown wrote:

> > The best way to handle this is to try to support both fixed and variable
> > clock rates, some other drivers do this by setting constraints based on
> > MCLK only if the MCLK has been set to a non-zero value.  They have the
> > machine drivers reset the clock rate to 0 when it goes idle so that no
> > constraints are applied then.  This means that if the machine has a

> In my understanding, fixed and variable clock both use set_sysclk() for
> telling their MCLK to codec driver. For fixed MCLK cases we need to
> apply constraint but for variable MCLK cases we should not set
> constraints at set_sysclk(). How can we identify these two cases...?

Like I say it's usually done by settingthe MCLK to 0 when not in use and
then not applying any constraints if there's no MCLK set.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 488 bytes
Desc: not available
URL: <http://mailman.alsa-project.org/pipermail/alsa-devel/attachments/20190903/61e1f371/attachment.sig>


More information about the Alsa-devel mailing list