Re: [PATCH 1/2] dt-bindings: iio: accel: Add SCA3300 documentation

[Jonathan Cameron]

On Mon, 12 Apr 2021 10:50:55 +0300
Tomas Melin <tomas.melin@xxxxxxxxxxx> wrote:

> initial DT bindings for Murata SCA3300 Accelerometer.
> 
> Signed-off-by: Tomas Melin <tomas.melin@xxxxxxxxxxx>
Hi Tomas.
> ---
>  .../bindings/iio/accel/sca3300.yaml           | 51 +++++++++++++++++++
>  1 file changed, 51 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/iio/accel/sca3300.yaml
> 
> diff --git a/Documentation/devicetree/bindings/iio/accel/sca3300.yaml b/Documentation/devicetree/bindings/iio/accel/sca3300.yaml
> new file mode 100644
> index 000000000000..32fe4b647cd0
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/accel/sca3300.yaml

Vendor prefix on the filename please.

> @@ -0,0 +1,51 @@
> +# SPDX-License-Identifier: (GPL-2.0-only)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/iio/accel/sca3300.yaml#

Vendor prefix will end up here as well.

> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Murata SCA3300 Accelerometer
> +
> +description: |
> +  3-axis industrial accelerometer with digital SPI interface
> +  https://www.murata.com/en-global/products/sensor/accel/sca3300
> +
> +maintainers:
> +  - Tomas Melin <tomas.melin@xxxxxxxxxxx>
> +
> +properties:
> +  compatible:
> +    enum:
> +      - murata,sca3300
> +
> +  reg:
> +    maxItems: 1
> +    description: SPI chip select number according to the general SPI bindings

No need to give a description as this is the same for all SPI devices.

> +
> +  spi-max-frequency:
> +    maximum: 8000000
> +
> +  murata,opmode:
> +    description: Accelerometer operation mode as described in datasheet (MODE)
> +    $ref: /schemas/types.yaml#/definitions/uint32

This needs a proper description here.  Also perhaps worth noting that we
very rarely let mode related things like this into DT. They are always almost
something that is policy rather than hardware description and so belong somewhere
userspace can control them.

In this particular case, looks like a simple range control.   That belongs in 
userspace via _scale attributes.

> +
> +required:
> +  - compatible
> +  - reg
> +  - murata,opmode
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    spi {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +        sca3300@0 {
> +            compatible = "murata,sca3300";
> +            reg = <0x0>;
> +            spi-max-frequency = <4000000>;
> +            murata,opmode = <4>;
> +        };
> +    };
> +...