Subject: Re: [net-next RFC PATCH 03/14] dt-bindings: net: document ethernet PHY package nodes

From: Rob Herring <[email-masked]>
Date: Mon, 20 Nov 2023 10:41:33 -0700

On Mon, Nov 20, 2023 at 02:50:30PM +0100, Christian Marangi wrote:
> Document ethernet PHY package nodes used to describe PHY shipped in
> bundle of 4-5 PHY. These particular PHY require specific PHY in the
> package for global onfiguration of the PHY package.
> 
> Example are PHY package that have some regs only in one PHY of the
> package and will affect every other PHY in the package, for example
> related to PHY interface mode calibration or global PHY mode selection.
> 
> The PHY package node should use the global-phys property and the
> global-phy-names to define PHY in the package required by the PHY driver
> for global configuration.
> 
> It's also possible to specify the property phy-mode to specify that the
> PHY package sets a global PHY interface mode and every PHY of the
> package requires to have the same PHY interface mode.
> 
> Signed-off-by: Christian Marangi <[email-masked]>
> ---
>  .../bindings/net/ethernet-phy-package.yaml    | 86 +++++++++++++++++++
>  1 file changed, 86 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/net/ethernet-phy-package.yaml
> 
> diff --git a/Documentation/devicetree/bindings/net/ethernet-phy-package.yaml b/Documentation/devicetree/bindings/net/ethernet-phy-package.yaml
> new file mode 100644
> index 000000000000..2aa109e155d9
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/net/ethernet-phy-package.yaml
> @@ -0,0 +1,86 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/net/ethernet-phy-package.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Ethernet PHY Package Common Properties
> +
> +maintainers:
> +  - Christian Marangi <[email-masked]

Missing a '>'

> +
> +properties:
> +  $nodename:
> +    pattern: "^ethernet-phy-package(-[0-9]+)?$"
> +
> +  compatible:
> +    const: ethernet-phy-package
> +
> +  '#address-cells':
> +    description: number of address cells for the MDIO bus
> +    const: 1
> +
> +  '#size-cells':
> +    description: number of size cells on the MDIO bus
> +    const: 0
> +
> +  global-phys:
> +    $ref: /schemas/types.yaml#/definitions/phandle-array
> +    minItems: 1
> +    maxItems: 31
> +    description:
> +      List of phandle to the PHY in the package required and
> +      used to configure the PHY package.
> +
> +  global-phy-names:
> +    $ref: /schemas/types.yaml#/definitions/string-array
> +    minItems: 1
> +    maxItems: 31
> +    description:
> +      List of names of the PHY defined in global-phys.
> +
> +  phy-connection-type:
> +    $ref: /schemas/net/ethernet-phy-mode-types.yaml#definitions/phy-connection-type
> +    description:
> +      Specifies global interface type for the PHY package.
> +
> +  phy-mode:
> +    $ref: "#/properties/phy-connection-type"
> +
> +patternProperties:
> +  ^ethernet-phy(@[a-f0-9]+)?$:
> +    $ref: /schemas/net/ethernet-phy.yaml#
> +
> +required:
> +  - compatible
> +
> +dependencies:
> +  global-phy-names: [global-phys]
> +
> +unevaluatedProperties: false
> +
> +examples:
> +  - |
> +    ethernet {

You mean 'mdio' here, right?

> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        ethernet-phy-package {

This doesn't work. Child nodes of MDIO bus must be an MDIO device with 
an address. What you need is a node with all the addresses of the 
device:

mdio {
  ...

  ethernet-phy@1 {
    compatible = "vendor,specifc-compatible-for-device";
    reg = <1>, <4>;
    ...
  };
};

There's also some MDIO devices which define a secondary address as a 
child device. Maybe those are similar to your situation. I don't recall 
which ones offhand.

> +            compatible = "ethernet-phy-package";
> +            #address-cells = <1>;
> +            #size-cells = <0>;
> +
> +            global-phys = <&phy4>;
> +            global-phy-names = "base";
> +
> +            ethernet-phy@1 {
> +              compatible = "ethernet-phy-ieee802.3-c22";
> +              reg = <1>;
> +            };
> +
> +            phy4: ethernet-phy@4 {
> +              compatible = "ethernet-phy-ieee802.3-c22";
> +              reg = <4>;
> +            };
> +        };
> +    };
> -- 
> 2.40.1
>