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

From: Charles Keepax
Date: Thu Sep 14 2023 - 05:21:44 EST


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@xxxxxxxxxx>
> ---
> +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.

Thanks,
Charles