Re: [PATCH v2 1/3] ASoC: wm8782: Handle maximum audio rate at runtime

John Watts
2023-09-14T09:31:51Z

On Thu, Sep 14, 2023 at 09:21:07AM +0000, Charles Keepax wrote:
> On Thu, Sep 14, 2023 at 03:15:50AM +1000, John Watts wrote:
> > The wm8782 supports up to 192kHz audio when pins are set correctly.
> > Instead of hardcoding which rates are supported enable them all
> > then refer to a max_rate variable at runtime.
> >
> > Signed-off-by: John Watts <contact@jookia.org>
> > ---
> > +static int wm8782_dai_hw_params(struct snd_pcm_substream *component,
> > + struct snd_pcm_hw_params *params,
> > + struct snd_soc_dai *dai)
> > +{
> > + struct wm8782_priv *priv =
> > + snd_soc_component_get_drvdata(dai->component);
> > +
> > + if (params_rate(params) > priv->max_rate)
> > + return -EINVAL;
> > +
> > + return 0;
> > +}
>
> We should be setting this as a constraint in startup, rather
> than returning an error in hw_params. That will let user-space
> know the supported rates and allow it to resample if necessary.

How do you do this? The struct with the rate is statically defined.

>
> Thanks,
> Charles

John.