[alsa-devel] [PATCH 2/2] dt: binding: sound cs42l52 driver

[Mark Rutland]

On Thu, Nov 07, 2013 at 08:22:17PM +0000, Brian Austin wrote:
> Add Device Tree Binding for the CS42L52 Codec
> 
> Signed-off-by: Brian Austin <brian.austin at cirrus.com>
> ---
>  .../devicetree/bindings/sound/cs42l52.txt          | 34 ++++++++++++++++++++++
>  1 file changed, 34 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/sound/cs42l52.txt
> 
> diff --git a/Documentation/devicetree/bindings/sound/cs42l52.txt b/Documentation/devicetree/bindings/sound/cs42l52.txt
> new file mode 100644
> index 0000000..7540198
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/sound/cs42l52.txt
> @@ -0,0 +1,34 @@
> +CS42L52 audio CODEC
> +
> +Required properties:
> +
> +  - compatible : "cirrus,cs42l52"
> +
> +  - reg : the I2C address of the device for I2C
> +
> +Optional properties:
> +
> +  - reset_gpio : a GPIO spec for the reset pin.

Nit: device tree convention is to use '-' rather than '_'. So this
should be reset-gpio rather than reset_gpio.

s/_/-/ for the later property names too.

s/GPIO spec/phandle + gpio-specifier/

> +  - chgfreq    : Charge Pump Frequency values 0x00-0x0F

In general, longer but more easily understood names are preferred (e.g.
"clock-frequency"). This could be "charge-pump-frequency".

When you say "values 0x00-0x0F" you mean the value is in that range?
Inclusive?

Due to punctuation, upon first reading I read this as being an array of
values.  It would be nice to have some clarification to prevent others
maknig the smae mistake.

> +  - mica_sel   : MIC A single ended input select MIC1/MIC2
> +  - micb_sel   : MIC B single ended input select MIC1/MIC2

Is this a boolean? What values are expected?

Could you elaborate on what this describes?

> +  - mica_cfg   : MIC A single-ended or differential select
> +  - micb_cfg   : MIC A single-ended or differential select

Could you elaborate on what these describe, what values are expected,
etc?

> +  - micbias_lvl: Set the output voltage level on the MICBIAS Pin
> +		 0x00 = 0.5 x VA
> +		 0x01 = 0.6 x VA
> +		 0x02 = 0.7 x VA
> +		 0x03 = 0.8 x VA
> +		 0x04 = 0.83 x VA
> +		 0x05 = 0.91 x VA

Is this not something we'd want to change at runtime instead? Why does
this need to be in the dt?

Thanks,
Mark.