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

title: Lantiq SoC External Bus memory mapped GPIO controller

maintainers:
  - John Crispin <john@phrozen.org>

description: |
  By attaching hardware latches to the EBU it is possible to create output
  only gpios. This driver configures a special memory address, which when
  written to outputs 16 bit to the latches.
 
  The node describing the memory mapped GPIOs needs to be a child of the node
  describing the "lantiq,localbus".

properties:
  compatible:
    enum:
      - lantiq,gpio-mm-lantiq
      - lantiq,gpio-mm

  reg:
    maxItems: 1
 
  '#gpio-cells':
    const: 2

  gpio-controller: true

  lantiq,shadow:
    description: The default value that we shall assume as already set on the shift register cascade.
    $ref: /schemas/types.yaml#/definitions/uint32

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

additionalProperties: false

examples:
  - |
    gpio@4000000 {
        compatible = "lantiq,gpio-mm-lantiq";
        reg = <0x4000000 0x10>;
        gpio-controller;
        #gpio-cells = <2>;
        lantiq,shadow = <0x77f>;
    };