[PATCH 2/4] dt-bindings: net: dsa: document internal MDIO bus

[Vladimir Oltean]

On Sat, Aug 12, 2023 at 12:17:06PM +0300, Arınç ÜNAL wrote:
> Add the schema to document the internal MDIO bus. Adjust realtek.yaml
> accordingly.
> 
> Signed-off-by: Arınç ÜNAL <arinc.unal at arinc9.com>
> ---
>  .../devicetree/bindings/net/dsa/dsa.yaml      | 18 +++++
>  .../devicetree/bindings/net/dsa/realtek.yaml  | 66 +++++++++----------
>  2 files changed, 50 insertions(+), 34 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/net/dsa/dsa.yaml b/Documentation/devicetree/bindings/net/dsa/dsa.yaml
> index ec74a660beda..03ccedbc49dc 100644
> --- a/Documentation/devicetree/bindings/net/dsa/dsa.yaml
> +++ b/Documentation/devicetree/bindings/net/dsa/dsa.yaml
> @@ -31,6 +31,24 @@ properties:
>        (single device hanging off a CPU port) must not specify this property
>      $ref: /schemas/types.yaml#/definitions/uint32-array
>  
> +  mdio:
> +    description: The internal MDIO bus of the switch
> +    $ref: /schemas/net/mdio.yaml#
> +
> +if:
> +  required: [ mdio ]
> +then:
> +  patternProperties:
> +    "^(ethernet-)?ports$":
> +      patternProperties:
> +        "^(ethernet-)?port@[0-9]+$":
> +          if:
> +            not:
> +              required: [ ethernet ]

To match only on user ports, this must also exclude DSA ports ("required: [ link ]").

> +          then:
> +            required:
> +              - phy-handle

No. The only thing permitted by the slave_mii_bus is to do something meaningful
when phylink bindings ("phy-handle", "fixed-link" or "managed") are absent. But
the presence of slave_mii_bus does not imply that user ports have a required
phy-handle. They might be SerDes ports or xMII ports. So they might use "managed"
or "fixed-link". The only thing that you can enforce is that, if the slave_mii_bus
has an OF presence, then user ports must have phylink bindings.

> +
>  additionalProperties: true
>  
>  $defs:
> diff --git a/Documentation/devicetree/bindings/net/dsa/realtek.yaml b/Documentation/devicetree/bindings/net/dsa/realtek.yaml
> index cfd69c2604ea..ea7db0890abc 100644
> --- a/Documentation/devicetree/bindings/net/dsa/realtek.yaml
> +++ b/Documentation/devicetree/bindings/net/dsa/realtek.yaml
> @@ -6,9 +6,6 @@ $schema: http://devicetree.org/meta-schemas/core.yaml#
>  
>  title: Realtek switches for unmanaged switches
>  
> -allOf:
> -  - $ref: dsa.yaml#/$defs/ethernet-ports
> -
>  maintainers:
>    - Linus Walleij <linus.walleij at linaro.org>
>  
> @@ -95,37 +92,38 @@ properties:
>        - '#address-cells'
>        - '#interrupt-cells'
>  
> -  mdio:
> -    $ref: /schemas/net/mdio.yaml#
> -    unevaluatedProperties: false
> -
> -    properties:
> -      compatible:
> -        const: realtek,smi-mdio
> -
> -if:
> -  required:
> -    - reg
> -
> -then:
> -  $ref: /schemas/spi/spi-peripheral-props.yaml#
> -  not:
> -    required:
> -      - mdc-gpios
> -      - mdio-gpios
> -      - mdio
> -
> -  properties:
> -    mdc-gpios: false
> -    mdio-gpios: false
> -    mdio: false
> -
> -else:
> -  required:
> -    - mdc-gpios
> -    - mdio-gpios
> -    - mdio
> -    - reset-gpios
> +allOf:
> +  - $ref: dsa.yaml#/$defs/ethernet-ports
> +  - if:
> +      required: [ mdio ]
> +    then:
> +      properties:
> +        mdio:
> +          properties:
> +            compatible:
> +              const: realtek,smi-mdio
> +
> +  - if:
> +      required:
> +        - reg
> +    then:
> +      $ref: /schemas/spi/spi-peripheral-props.yaml#
> +      not:
> +        required:
> +          - mdc-gpios
> +          - mdio-gpios
> +          - mdio
> +
> +      properties:
> +        mdc-gpios: false
> +        mdio-gpios: false
> +        mdio: false
> +    else:
> +      required:
> +        - mdc-gpios
> +        - mdio-gpios
> +        - mdio
> +        - reset-gpios
>  
>  required:
>    - compatible
> -- 
> 2.39.2
>