linux/Documentation/devicetree/bindings/mux/reg-mux.yaml

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

title: Generic register bitfield-based multiplexer controller bindings

maintainers:
  - Peter Rosin <peda@axentia.se>

description: |+
  Define register bitfields to be used to control multiplexers. The parent
  device tree node must be a device node to provide register r/w access.  

properties:
  compatible:
    enum:
      - reg-mux   # parent device of mux controller is not syscon device
      - mmio-mux  # parent device of mux controller is syscon device

  reg: true

  '#mux-control-cells':
    const: 1

  mux-reg-masks:
    $ref: /schemas/types.yaml#/definitions/uint32-matrix
    items:
      items:
        - description: register offset
        - description: pre-shifted bitfield mask
    description: Each entry pair describes a single mux control.

  idle-states: true

required:
  - compatible
  - mux-reg-masks
  - '#mux-control-cells'

additionalProperties: false

examples:
  - |
    /* The parent device of mux controller is not a syscon device. */

    #include <dt-bindings/mux/mux.h>

    mux-controller {
        compatible = "reg-mux";
        #mux-control-cells = <1>;
        mux-reg-masks =
            <0x54 0xf8>, /* 0: reg 0x54, bits 7:3 */
            <0x54 0x07>; /* 1: reg 0x54, bits 2:0 */
    };

    mdio-mux-1 {
        compatible = "mdio-mux-multiplexer";
        mux-controls = <&mux1 0>;
        mdio-parent-bus = <&emdio1>;
        #address-cells = <1>;
        #size-cells = <0>;

        mdio@0 {
            reg = <0x0>;
            #address-cells = <1>;
            #size-cells = <0>;
        };

        mdio@8 {
            reg = <0x8>;
            #address-cells = <1>;
            #size-cells = <0>;
        };
    };

    mdio-mux-2 {
        compatible = "mdio-mux-multiplexer";
        mux-controls = <&mux1 1>;
        mdio-parent-bus = <&emdio2>;
        #address-cells = <1>;
        #size-cells = <0>;

        mdio@0 {
            reg = <0x0>;
            #address-cells = <1>;
            #size-cells = <0>;
        };

        mdio@1 {
            reg = <0x1>;
            #address-cells = <1>;
            #size-cells = <0>;
        };
    };    

  - |
    /* The parent device of mux controller is syscon device. */

    #include <dt-bindings/mux/mux.h>
    syscon@1000 {
        reg = <0x1000 0x100>;

        mux2: mux-controller {
            compatible = "mmio-mux";
            #mux-control-cells = <1>;

            mux-reg-masks =
                <0x3 0x30>, /* 0: reg 0x3, bits 5:4 */
                <0x3 0x40>; /* 1: reg 0x3, bit 6 */
            idle-states = <MUX_IDLE_AS_IS>, <0>;
        };
    };

    video-mux {
        compatible = "video-mux";
        mux-controls = <&mux2 0>;
        #address-cells = <1>;
        #size-cells = <0>;

        ports {
            #address-cells = <1>;
            #size-cells = <0>;

            /* inputs 0..3 */
            port@0 {
                reg = <0>;
            };
            port@1 {
                reg = <1>;
            };
            port@2 {
                reg = <2>;
            };
            port@3 {
                reg = <3>;
            };

            /* output */
            port@4 {
                reg = <4>;
            };
        };
    };    
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