xref: /freebsd/sys/contrib/device-tree/Bindings/gpio/pisosr-gpio.yaml (revision 833e5d42ab135b0238e61c5b3c19b8619677cbfa)

# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
%YAML 1.2
---
$id: http://devicetree.org/schemas/gpio/pisosr-gpio.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#

title: Generic Parallel-in/Serial-out Shift Register GPIO Driver

description:
  This binding describes generic parallel-in/serial-out shift register
  devices that can be used for GPI (General Purpose Input). This includes
  SN74165 serial-out shift registers and the SN65HVS88x series of
  industrial serializers.

maintainers:
  - Frank Li <Frank.Li@nxp.com>

properties:
  compatible:
    enum:
      - pisosr-gpio

  gpio-controller: true

  '#gpio-cells':
    const: 2

  ngpios:
    maximum: 32
    default: 8

  load-gpios:
    description:
      GPIO pin specifier attached to load enable, this
      pin is pulsed before reading from the device to
      load input pin values into the device.

  spi-cpol: true

required:
  - compatible
  - gpio-controller
  - '#gpio-cells'

allOf:
  - $ref: /schemas/spi/spi-peripheral-props.yaml#

unevaluatedProperties: false

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

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

        gpio@0 {
            compatible = "pisosr-gpio";
            reg = <0>;
            gpio-controller;
            #gpio-cells = <2>;
            load-gpios = <&gpio2 23 GPIO_ACTIVE_LOW>;
            spi-max-frequency = <1000000>;
            spi-cpol;
        };
    };