Re: [PATCH v1 1/4] dt-bindings: ASoC: Add TDA7802 amplifier

[Charles Keepax <ckeepax@opensource.cirrus.com>]

On Tue, Jun 11, 2019 at 06:49:06PM +0100, Thomas Preston wrote:
> Signed-off-by: Thomas Preston <thomas.preston@codethink.co.uk>
> Cc: Patrick Glaser <pglaser@tesla.com>
> Cc: Rob Duncan <rduncan@tesla.com>
> Cc: Nate Case <ncase@tesla.com>
> ---
>  .../devicetree/bindings/sound/tda7802.txt          | 26 ++++++++++++++++++++++
>  1 file changed, 26 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/sound/tda7802.txt
> 
> diff --git a/Documentation/devicetree/bindings/sound/tda7802.txt b/Documentation/devicetree/bindings/sound/tda7802.txt
> new file mode 100644
> index 000000000000..f80aaf4f1ba0
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/sound/tda7802.txt
> @@ -0,0 +1,26 @@
> +ST TDA7802 audio processor
> +
> +This device supports I2C only.
> +
> +Required properties:
> +
> +- compatible : "st,tda7802"
> +- reg : the I2C address of the device
> +- enable-supply : a regulator spec for the PLLen pin
> +
> +Optional properties:
> +
> +- st,gain-ch13 : gain for channels 1 and 3 (range: 1-4)
> +- st,gain-ch24 : gain for channels 2 and 3 (range: 1-4)

Does it make sense to have the gains in device tree? Are these
expected to be fixed by the system design, normally the gain
would be controlled through an ALSA control.

Thanks,
Charles