Documentation/devicetree/bindings/net/mdio-mux-mmioreg.yaml

# SPDX-License-Identifier: GPL-2.0
%YAML 1.2
---
$id: http://devicetree.org/schemas/net/mdio-mux-mmioreg.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#

title: Properties for an MDIO bus multiplexer controlled by a memory-mapped device

maintainers:
  - Andrew Lunn <andrew@lunn.ch>

description: |+
  This is a special case of a MDIO bus multiplexer.  A memory-mapped device,
  like an FPGA, is used to control which child bus is connected.  The mdio-mux
  node must be a child of the memory-mapped device.  The driver currently only
  supports devices with 8, 16 or 32-bit registers.

allOf:
  - $ref: /schemas/net/mdio-mux.yaml#

properties:
  compatible:
    items:
      - const: mdio-mux-mmioreg
      - const: mdio-mux

  reg:
    description: Contains the offset of the register that controls the bus
      multiplexer. The size field in the 'reg' property is the size of register,
      and must therefore be 1, 2, or 4.
    maxItems: 1

  mux-mask:
    $ref: /schemas/types.yaml#/definitions/uint32
    description: Contains an eight-bit mask that specifies which bits in the
      register control the actual bus multiplexer.  The 'reg' property of each
      child mdio-mux node must be constrained by this mask.

required:
  - compatible
  - reg
  - mux-mask

unevaluatedProperties: false

examples:
  - |
    mdio-mux@9 {
        compatible = "mdio-mux-mmioreg", "mdio-mux";
        mdio-parent-bus = <&xmdio0>;
        #address-cells = <1>;
        #size-cells = <0>;
        reg = <9 1>; // BRDCFG1
        mux-mask = <0x6>; // EMI2

        mdio@0 {  // Slot 1 XAUI (FM2)
            reg = <0>;
            #address-cells = <1>;
            #size-cells = <0>;

            phy_xgmii_slot1: ethernet-phy@4 {
                compatible = "ethernet-phy-ieee802.3-c45";
                reg = <4>;
            };
        };

        mdio@2 {  // Slot 2 XAUI (FM1)
            reg = <2>;
            #address-cells = <1>;
            #size-cells = <0>;

            ethernet-phy@4 {
                compatible = "ethernet-phy-ieee802.3-c45";
                reg = <4>;
            };
        };
    };
...