xref: /freebsd/sys/contrib/device-tree/Bindings/mux/gpio-mux.yaml (revision 5956d97f4b3204318ceb6aa9c77bd0bc6ea87a41)

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

title: GPIO-based multiplexer controller bindings

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

description: |+
  Define what GPIO pins are used to control a multiplexer. Or several
  multiplexers, if the same pins control more than one multiplexer.

  The multiplexer state is defined as the number represented by the
  multiplexer GPIO pins, where the first pin is the least significant
  bit. An active pin is a binary 1, an inactive pin is a binary 0.

properties:
  compatible:
    const: gpio-mux

  mux-gpios:
    description:
      List of gpios used to control the multiplexer, least significant bit first.

  '#mux-control-cells':
    const: 0

  idle-state:
    default: -1

required:
  - compatible
  - mux-gpios
  - "#mux-control-cells"

additionalProperties: false

examples:
  - |
    #include <dt-bindings/gpio/gpio.h>

    mux: mux-controller {
        compatible = "gpio-mux";
        #mux-control-cells = <0>;

        mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>,
              <&pioA 1 GPIO_ACTIVE_HIGH>;
    };

    adc-mux {
        compatible = "io-channel-mux";
        io-channels = <&adc 0>;
        io-channel-names = "parent";

        mux-controls = <&mux>;

        channels = "sync-1", "in", "out", "sync-2";
    };

    i2c-mux {
        compatible = "i2c-mux";
        i2c-parent = <&i2c1>;

        mux-controls = <&mux>;

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

        i2c@0 {
            reg = <0>;
            #address-cells = <1>;
            #size-cells = <0>;

            ssd1307: oled@3c {
                reg = <0x3c>;
            };
        };

        i2c@3 {
            reg = <3>;
            #address-cells = <1>;
            #size-cells = <0>;

            pca9555: pca9555@20 {
                reg = <0x20>;
            };
        };
    };
...