Re: [PATCH v4 2/3] dt-bindings: i2c: realtek,rtl9301-i2c: extend for RTL9310 support

[Rob Herring <robh@kernel.org>]

On Tue, Jul 29, 2025 at 07:51:44AM +0000, Jonas Jelonek wrote:
> Add dt-bindings for RTL9310 series I2C controller.
> 
> Adjust the regex for child-node address to account for the fact that
> RTL9310 supports 12 instead of only 8 SDA lines. Also, narrow this per
> variant.
> 
> Add a vendor-specific property to explicitly specify the
> Realtek-internal ID of the defined I2C controller/master. This is
> required, in particular for RTL9310, to describe the correct I2C
> master. Require this property for RTL9310.
> 
> Add compatibles for known SoC variants RTL9311, RTL9312 and RTL9313.
> 
> Signed-off-by: Jonas Jelonek <jelonek.jonas@gmail.com>
> ---
>  .../bindings/i2c/realtek,rtl9301-i2c.yaml     | 58 +++++++++++++++++--
>  1 file changed, 53 insertions(+), 5 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/i2c/realtek,rtl9301-i2c.yaml b/Documentation/devicetree/bindings/i2c/realtek,rtl9301-i2c.yaml
> index 69ac5db8b914..29676e99a8c3 100644
> --- a/Documentation/devicetree/bindings/i2c/realtek,rtl9301-i2c.yaml
> +++ b/Documentation/devicetree/bindings/i2c/realtek,rtl9301-i2c.yaml
> @@ -10,9 +10,11 @@ maintainers:
>    - Chris Packham <chris.packham@alliedtelesis.co.nz>
>  
>  description:
> -  The RTL9300 SoC has two I2C controllers. Each of these has an SCL line (which
> -  if not-used for SCL can be a GPIO). There are 8 common SDA lines that can be
> -  assigned to either I2C controller.
> +  The RTL9300 SoCs have two I2C controllers. Each of these has an SCL line
> +  (which if not-used for SCL can be a GPIO). There are 8 common SDA lines
> +  that can be assigned to either I2C controller.
> +  The RTL9310 SoCs have equal capabilities but support 12 common SDA lines
> +  which can be assigned to either I2C controller.
>  
>  properties:
>    compatible:
> @@ -23,7 +25,15 @@ properties:
>                - realtek,rtl9302c-i2c
>                - realtek,rtl9303-i2c
>            - const: realtek,rtl9301-i2c
> -      - const: realtek,rtl9301-i2c
> +      - items:
> +          - enum:
> +              - realtek,rtl9311-i2c
> +              - realtek,rtl9312-i2c
> +              - realtek,rtl9313-i2c
> +          - const: realtek,rtl9310-i2c
> +      - enum:
> +          - realtek,rtl9301-i2c
> +          - realtek,rtl9310-i2c
>  
>    reg:
>      items:
> @@ -35,8 +45,15 @@ properties:
>    "#size-cells":
>      const: 0
>  
> +  realtek,mst-id:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    description:
> +      Realtek-internal ID of the I2C controller/master.
> +    minimum: 1
> +    maximum: 2

We normally try to avoid instance IDs. Why not just a property defining 
the SCL # to use.

> +
>  patternProperties:
> -  '^i2c@[0-7]$':
> +  '^i2c@([0-9]|1[0-1])$':

Unit-addresses are typically hex.

>      $ref: /schemas/i2c/i2c-controller.yaml
>      unevaluatedProperties: false
>  
> @@ -48,6 +65,25 @@ patternProperties:
>      required:
>        - reg
>  
> +
> +allOf:
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            const: realtek,rtl9310-i2c
> +    then:
> +      required:
> +        - realtek,mst-id
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            const: realtek,rtl9301-i2c
> +    then:
> +      patternProperties:
> +        '^i2c@([8-9]|1[0-1])$': false
> +
>  required:
>    - compatible
>    - reg
> @@ -68,3 +104,15 @@ examples:
>          #size-cells = <0>;
>        };
>      };
> +  - |
> +    i2c@100c {
> +      compatible = "realtek,rtl9310-i2c";
> +      reg = <0x100c 0x18>;
> +      #address-cells = <1>;
> +      #size-cells = <0>;
> +      realtek,mst-id = <1>;
> +
> +      i2c@0 {
> +        reg = <0>;
> +      };
> +    };

Is this really different enough to justify another example?