[alsa-devel] ASoC:Question rate constraint between the dais

Mark Brown broonie at opensource.wolfsonmicro.com
Thu Mar 15 18:53:11 CET 2012

On Thu, Mar 15, 2012 at 03:23:04PM +0530, Ramesh Babu wrote:

> I need to make sure that all simultaneous playback and capture (across the
> all dai_links) needs to be of same frequency family.
> If the sampling frequency of  a new request is different from ongoing
> playback/capture, then it needs to be rejected.

> How do I handle it in machine driver?

Why do you need to do this in the machine driver?  Such a constraint
sounds like it's coming from one of the chips in the system rather than
from the machine itself so it'd seem sensible for the chip itself to
impose the constraint so that other machines don't need to replicate the

See wm8988 for an example of adding sample rate constraints, obviously
you can change the criteria dynamically.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 836 bytes
Desc: Digital signature
Url : http://mailman.alsa-project.org/pipermail/alsa-devel/attachments/20120315/79bb7202/attachment.sig 

More information about the Alsa-devel mailing list