Re: [PATCH 4/7] dt-bindings: firmware: arm,scmi: support pinctrl protocol

[Rob Herring <robh@xxxxxxxxxx>]

On Fri, Dec 15, 2023 at 07:56:32PM +0800, Peng Fan (OSS) wrote:
> From: Peng Fan <peng.fan@xxxxxxx>
> 
> Add SCMI v3.2 pinctrl protocol bindings and example.
> 
> Signed-off-by: Peng Fan <peng.fan@xxxxxxx>
> ---
>  .../devicetree/bindings/firmware/arm,scmi.yaml     | 99 ++++++++++++++++++++++
>  1 file changed, 99 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/firmware/arm,scmi.yaml b/Documentation/devicetree/bindings/firmware/arm,scmi.yaml
> index 4591523b51a0..bfd2b6a89979 100644
> --- a/Documentation/devicetree/bindings/firmware/arm,scmi.yaml
> +++ b/Documentation/devicetree/bindings/firmware/arm,scmi.yaml
> @@ -247,6 +247,85 @@ properties:
>        reg:
>          const: 0x18
>  
> +  protocol@19:
> +    type: object
> +    allOf:
> +      - $ref: '#/$defs/protocol-node'
> +      - $ref: /schemas/pinctrl/pinctrl.yaml
> +      - if:
> +          properties:
> +            compatible:
> +              const: fsl,imx95-scmi-pinctrl
> +        then:
> +          patternProperties:
> +            "grp$": false
> +            "-pins$": true
> +        else:
> +          patternProperties:
> +            "grp$": false
> +            "-pins$": true
> +    unevaluatedProperties: false

This will not scale if each vendor adds to arm,scmi.yaml. You need to 
move this to its own file. That can have a ref to 
/schemas/firmware/arm,scmi.yaml#/$defs/protocol-node.

Here you can just say compatible is "fsl,imx95-scmi-pinctrl" and 
'additionalProperties: true'.

> +
> +    properties:
> +      reg:
> +        const: 0x19
> +
> +      '#pinctrl-cells':
> +        const: 0

Generally not used if 0.

> +
> +      compatible:
> +        const: fsl,imx95-scmi-pinctrl
> +
> +    patternProperties:
> +      '-pins$':
> +        type: object
> +        allOf:
> +          - $ref: /schemas/pinctrl/pincfg-node.yaml#
> +          - $ref: /schemas/pinctrl/pinmux-node.yaml#
> +        unevaluatedProperties: false
> +
> +        description:
> +          A pin multiplexing sub-node describe how to configure a
> +          set of pins is some desired function.
> +          A single sub-node may define several pin configurations.
> +          This sub-node is using default pinctrl bindings to configure
> +          pin multiplexing and using SCMI protocol to apply specified
> +          configuration using SCMI protocol.
> +
> +      'grp$':
> +        type: object
> +        description:
> +          Pinctrl node's client devices use subnodes for desired pin configuration.
> +          Client device subnodes use below standard properties.
> +
> +        properties:
> +          fsl,pins:
> +            description:
> +              each entry consists of 6 integers and represents the mux and config
> +              setting for one pin. The first 5 integers <mux_reg conf_reg input_reg
> +              mux_val input_val> are specified using a PIN_FUNC_ID macro, which can
> +              be found in <arch/arm64/boot/dts/freescale/imx95-pinfunc.h>. The last
> +              integer CONFIG is the pad setting value like pull-up on this pin. Please
> +              refer to i.MX95 Plus Reference Manual for detailed CONFIG settings.
> +            $ref: /schemas/types.yaml#/definitions/uint32-matrix
> +            items:
> +              items:
> +                - description: |
> +                    "mux_reg" indicates the offset of mux register.
> +                - description: |
> +                    "conf_reg" indicates the offset of pad configuration register.
> +                - description: |
> +                    "input_reg" indicates the offset of select input register.
> +                - description: |
> +                    "mux_val" indicates the mux value to be applied.
> +                - description: |
> +                    "input_val" indicates the select input value to be applied.
> +                - description: |
> +                    "pad_setting" indicates the pad configuration value to be applied.
> +
> +    required:
> +      - reg
> +
>  additionalProperties: false
>  
>  $defs:
> @@ -401,6 +480,26 @@ examples:
>              scmi_powercap: protocol@18 {
>                  reg = <0x18>;
>              };
> +
> +            scmi_pinctrl: protocol@19 {
> +                reg = <0x19>;
> +                #pinctrl-cells = <0>;

Missing compatible. Schema should catch that...

> +
> +                i2c2-pins {
> +                    groups = "i2c2_a", "i2c2_b";
> +                    function = "i2c2";
> +                };
> +
> +                mdio-pins {
> +                    groups = "avb_mdio";
> +                    drive-strength = <24>;
> +                };
> +
> +                keys_pins: keys-pins {
> +                    pins = "GP_5_17", "GP_5_20", "GP_5_22", "GP_2_1";
> +                    bias-pull-up;
> +                };
> +            };
>          };
>      };
>  
> 
> -- 
> 2.37.1
>