Re: [PATCH net-next v15 01/15] dt-bindings: net: Introduce the ethernet-connector description

[Rob Herring <robh@kernel.org>]

On Thu, Nov 06, 2025 at 10:47:26AM +0100, Maxime Chevallier wrote:
> The ability to describe the physical ports of Ethernet devices is useful
> to describe multi-port devices, as well as to remove any ambiguity with
> regard to the nature of the port.
> 
> Moreover, describing ports allows for a better description of features
> that are tied to connectors, such as PoE through the PSE-PD devices.
> 
> Introduce a binding to allow describing the ports, for now with 2
> attributes :
> 
>  - The number of lanes, which is a quite generic property that allows
>    differentating between multiple similar technologies such as BaseT1
>    and "regular" BaseT (which usually means BaseT4).
> 
>  - The media that can be used on that port, such as BaseT for Twisted
>    Copper, BaseC for coax copper, BaseS/L for Fiber, BaseK for backplane
>    ethernet, etc. This allows defining the nature of the port, and
>    therefore avoids the need for vendor-specific properties such as
>    "micrel,fiber-mode" or "ti,fiber-mode".
> 
> The port description lives in its own file, as it is intended in the
> future to allow describing the ports for phy-less devices.
> 
> Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
> ---
>  .../bindings/net/ethernet-connector.yaml      | 53 +++++++++++++++++++
>  .../devicetree/bindings/net/ethernet-phy.yaml | 18 +++++++
>  MAINTAINERS                                   |  1 +
>  3 files changed, 72 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/net/ethernet-connector.yaml
> 
> diff --git a/Documentation/devicetree/bindings/net/ethernet-connector.yaml b/Documentation/devicetree/bindings/net/ethernet-connector.yaml
> new file mode 100644
> index 000000000000..2b67907582c7
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/net/ethernet-connector.yaml
> @@ -0,0 +1,53 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/net/ethernet-connector.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Generic Ethernet Connector
> +
> +maintainers:
> +  - Maxime Chevallier <maxime.chevallier@bootlin.com>
> +
> +description:
> +  An Ethernet Connector represents the output of a network component such as
> +  a PHY, an Ethernet controller with no PHY, or an SFP module.
> +
> +properties:
> +
> +  pairs:
> +    description:
> +      Defines the number of BaseT pairs that are used on the connector.
> +    $ref: /schemas/types.yaml#/definitions/uint32

Constraints? Wouldn't 4 pairs be the max?

Is it possible you need to know which pairs are wired?

> +
> +  media:

Both of these names are a bit generic though I don't have a better 
suggestion.

> +    description:
> +      The mediums, as defined in 802.3, that can be used on the port.
> +    enum:
> +      - BaseT
> +      - BaseK
> +      - BaseS
> +      - BaseC
> +      - BaseL
> +      - BaseD
> +      - BaseE
> +      - BaseF
> +      - BaseV
> +      - BaseMLD
> +
> +required:
> +  - media
> +
> +allOf:
> +  - if:
> +      properties:
> +        media:
> +          contains:
> +            const: BaseT
> +    then:
> +      required:
> +        - pairs

else:
  properties:
    pairs: false

??

> +
> +additionalProperties: true
> +
> +...
> diff --git a/Documentation/devicetree/bindings/net/ethernet-phy.yaml b/Documentation/devicetree/bindings/net/ethernet-phy.yaml
> index 2ec2d9fda7e3..f434768d6bae 100644
> --- a/Documentation/devicetree/bindings/net/ethernet-phy.yaml
> +++ b/Documentation/devicetree/bindings/net/ethernet-phy.yaml
> @@ -277,6 +277,17 @@ properties:
>  
>      additionalProperties: false
>  
> +  mdi:
> +    type: object
> +
> +    patternProperties:
> +      '^connector-[a-f0-9]+$':

Unit addresses are hex, index suffixes are decimal: connector-[0-9]+


> +        $ref: /schemas/net/ethernet-connector.yaml#
> +
> +        unevaluatedProperties: false
> +
> +    additionalProperties: false
> +
>  required:
>    - reg
>  
> @@ -313,5 +324,12 @@ examples:
>                      default-state = "keep";
>                  };
>              };
> +            /* Fast Ethernet port, with only 2 pairs wired */
> +            mdi {
> +                connector-0 {
> +                    pairs = <2>;
> +                    media = "BaseT";
> +                };
> +            };
>          };
>      };
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 1ab7e8746299..19ba82b98616 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -9276,6 +9276,7 @@ R:	Russell King <linux@armlinux.org.uk>
>  L:	netdev@vger.kernel.org
>  S:	Maintained
>  F:	Documentation/ABI/testing/sysfs-class-net-phydev
> +F:	Documentation/devicetree/bindings/net/ethernet-connector.yaml
>  F:	Documentation/devicetree/bindings/net/ethernet-phy.yaml
>  F:	Documentation/devicetree/bindings/net/mdio*
>  F:	Documentation/devicetree/bindings/net/qca,ar803x.yaml
> -- 
> 2.49.0
>