Re: [PATCH 1/2] dt-bindings: adc: add AD717X

[Rob Herring <robh@kernel.org>]

On Thu, Aug 10, 2023 at 12:33:16PM +0300, Dumitru Ceclan wrote:
> The AD717x family offer a complete integrated Sigma-Delta ADC solution
> which can be used in high precision, low noise single channel
> applications or higher speed multiplexed applications. The Sigma-Delta
> ADC is intended primarily for measurement of signals close to DC but also
> delivers outstanding performance with input bandwidths out to ~10kHz.
> 
> Signed-off-by: Dumitru Ceclan <mitrutzceclan@gmail.com>
> ---
>  .../bindings/iio/adc/adi,ad717x.yaml          | 158 ++++++++++++++++++
>  1 file changed, 158 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/iio/adc/adi,ad717x.yaml
> 
> diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad717x.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad717x.yaml
> new file mode 100644
> index 000000000000..f12926e69958
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/adc/adi,ad717x.yaml
> @@ -0,0 +1,158 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +# Copyright 2023 Analog Devices Inc.
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/iio/adc/adi,ad717x.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Analog Devices AD717X ADC family SPI driver

Drop 'SPI driver'. This is not a driver.

> +
> +maintainers:
> +  - Ceclan Dumitru <dumitru.ceclan@analog.com>
> +
> +description: |
> +  Bindings for the Analog Devices AD717X ADC's. Datasheets for supported chips:
> +    https://www.analog.com/media/en/technical-documentation/data-sheets/AD7172-2.pdf
> +    https://www.analog.com/media/en/technical-documentation/data-sheets/AD7173-8.pdf
> +    https://www.analog.com/media/en/technical-documentation/data-sheets/AD7175-2.pdf
> +    https://www.analog.com/media/en/technical-documentation/data-sheets/AD7176-2.pdf
> +
> +properties:
> +  compatible:
> +    enum:
> +      - adi,ad7172-2
> +      - adi,ad7173-8
> +      - adi,ad7175-2
> +      - adi,ad7176-2
> +
> +  reg:
> +    maxItems: 1
> +
> +  interrupts:
> +    maxItems: 1
> +
> +  '#address-cells':
> +    const: 1
> +
> +  '#size-cells':
> +    const: 0
> +
> +  spi-max-frequency:
> +    maximum: 20000000
> +
> +  spi-cpol:
> +    type: boolean
> +
> +  spi-cpha:
> +    type: boolean
> +
> +  adi,temp-channel:
> +    description:
> +      Enables temperature reading channel
> +    type: boolean
> +
> +  dependencies:
> +    adi,temp-channel:
> +      compatible:
> +        enum:
> +          - adi,ad7172-2
> +          - adi,ad7173-8
> +          - adi,ad7175-2

That's not actually valid schema. You are missing "properties" above 
"compatible". I'm also not sure the tools which do a number of 
fixups/transforms on schemas would handle this. I do think this is a bit 
nicer than the if/then schemas we normally use for restricting 
properties by compatibles.

> +
> +

Extra blank line.

> +  required:
> +    - compatible
> +    - reg
> +    - interrupts
> +    - spi-cpol
> +    - spi-cpha

If the device(s) are not configurable, then you shouldn't need these 2 
properties. The driver can hardcode the correct setting.

> +
> +patternProperties:
> +  "^channel@([0-9a-f])$":

Don't need ().

> +    type: object
> +    $ref: adc.yaml
> +    unevaluatedProperties: false
> +
> +    properties:
> +      reg:
> +        description: Channel number
> +        minimum: 0
> +        maximum: 15
> +
> +      diff-channels:
> +        description:
> +          Analog input pins
> +        items:
> +          minimum: 0
> +          maximum: 31
> +      
> +      adi,bipolar:
> +        description: Specify if the channel should measure in bipolar mode.
> +        type: boolean
> +
> +    required:
> +      - reg
> +      - diff-channels
> +
> +allOf:
> +  - $ref: /schemas/spi/spi-peripheral-props.yaml#
> +
> +unevaluatedProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/gpio/gpio.h>
> +    #include <dt-bindings/interrupt-controller/irq.h>
> +
> +    spi {
> +      status = "okay";

Drop status.

You need #address-cells and #size-cells. Did you test this?

> +
> +      ad7173@0 {
> +        compatible = "adi,ad7173-8";
> +        reg = <0>;
> +
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        interrupts = <25 IRQ_TYPE_EDGE_FALLING>;
> +        interrupt-parent = <&gpio>;
> +        spi-max-frequency = <5000000>;
> +        spi-cpol;
> +        spi-cpha;
> +
> +        adi,temp-channel;
> +
> +        channel@0 {
> +          reg = <0>;
> +          adi,bipolar;
> +
> +          diff-channels = <0 1>;
> +        };
> +
> +        channel@1 {
> +          reg = <1>;
> +
> +          diff-channels = <2 3>;
> +        };
> +
> +        channel@2 {
> +          reg = <2>;
> +          adi,bipolar;
> +
> +          diff-channels = <4 5>;
> +        };
> +
> +        channel@3 {
> +          reg = <3>;
> +          adi,bipolar;
> +
> +          diff-channels = <6 7>;
> +        };
> +
> +        channel@4 {
> +          reg = <4>;
> +
> +          diff-channels = <8 9>;
> +        };
> +      };
> +    };
> -- 
> 2.30.2
>