[alsa-devel] ASoC machine driver: how to configure supported frame rates?

[Lars-Peter Clausen]

On 10/10/2014 06:12 PM, Sergej Sawazki wrote:
> Dear all,
>
> I'm writing an ALSA SoC machine driver. The codec on my board, as well
> as the cpu do support the following rates: SNDRV_PCM_RATE_8000_192000
>
> However, the codec, as well as the cpu are clock slaves and the clocks
> are fixed. Hence, my board does only support the 96kHz sample rate.
>
> Can someone give me some advice on how to tell ALSA that my board does
> only support the rate SNDRV_PCM_RATE_96000?
> I don't want to modify the codec and the platform driver.
>
> Any help would be highly appreciated.  Thanks!

You can apply additional constraints in the startup callback of the 
snd_soc_ops of DAI link in your board driver.

For example see sound/soc/samsung/h1940_uda1380.c

- Lars