Documentation/devicetree/bindings/pinctrl/microchip,mcp23s08.yaml

# SPDX-License-Identifier: GPL-2.0-only
%YAML 1.2
---
$id: http://devicetree.org/schemas/pinctrl/microchip,mcp23s08.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#

title: Microchip I/O expander with serial interface (I2C/SPI)

maintainers:
  - Himanshu Bhavani <himanshu.bhavani@siliconsignals.io>

description:
  Microchip MCP23008, MCP23017, MCP23S08, MCP23S17, MCP23S18 GPIO expander
  chips.These chips provide 8 or 16 GPIO pins with either I2C or SPI interface.

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

properties:
  compatible:
    enum:
      - microchip,mcp23s08
      - microchip,mcp23s17
      - microchip,mcp23s18
      - microchip,mcp23008
      - microchip,mcp23017
      - microchip,mcp23018

  reg:
    maxItems: 1

  gpio-controller: true

  '#gpio-cells':
    const: 2

  interrupt-controller: true

  '#interrupt-cells':
    const: 2

  interrupts:
    maxItems: 1

  reset-gpios:
    description: GPIO specifier for active-low reset pin.
    maxItems: 1

  microchip,spi-present-mask:
    description:
      Multiple SPI chips can share the same SPI chipselect. Set a bit in
      bit0-7 in this mask to 1 if there is a chip connected with the
      corresponding spi address set. For example if you have a chip with
      address 3 connected, you have to set bit3 to 1, which is 0x08. mcp23s08
      chip variant only supports bits 0-3. It is not possible to mix mcp23s08
      and mcp23s17 on the same chipselect. Set at least one bit to 1 for SPI
      chips.
    $ref: /schemas/types.yaml#/definitions/uint8

  microchip,irq-mirror:
    type: boolean
    description:
      Sets the mirror flag in the IOCON register. Devices with two interrupt
      outputs (these are the devices ending with 17 and those that have 16 IOs)
      have two IO banks IO 0-7 form bank 1 and IO 8-15 are bank 2. These chips
      have two different interrupt outputs One for bank 1 and another for
      bank 2. If irq-mirror is set, both interrupts are generated regardless of
      the bank that an input change occurred on. If it is not set,the interrupt
      are only generated for the bank they belong to.

  microchip,irq-active-high:
    type: boolean
    description:
      Sets the INTPOL flag in the IOCON register.This configures the IRQ output
      polarity as active high.

  drive-open-drain:
    type: boolean
    description:
      Sets the ODR flag in the IOCON register. This configures the IRQ output as
      open drain active low.

  pinmux:
    type: object
    properties:
      pins:
        description:
          The list of GPIO pins controlled by this node. Each pin name
          corresponds to a physical pin on the GPIO expander.
        items:
          pattern: '^gpio([0-9]|[1][0-5])$'
        maxItems: 16

      bias-pull-up:
        type: boolean
        description:
          Configures pull-up resistors for the GPIO pins. Absence of this
          property will leave the configuration in its default state.

    required:
      - pins

    additionalProperties: false

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

unevaluatedProperties: false

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

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

        gpio@21 {
            compatible = "microchip,mcp23017";
            reg = <0x21>;
            gpio-controller;
            #gpio-cells = <2>;

            interrupt-parent = <&gpio1>;
            interrupts = <17 IRQ_TYPE_LEVEL_LOW>;
            interrupt-controller;
            #interrupt-cells = <2>;

            microchip,irq-mirror;
            pinctrl-names = "default";
            pinctrl-0 = <&pinctrl_i2c_gpio0>, <&gpiopullups>;
            reset-gpios = <&gpio6 15 GPIO_ACTIVE_LOW>;

            gpiopullups: pinmux {
                pins = "gpio0", "gpio1", "gpio2", "gpio3",
                       "gpio4", "gpio5", "gpio6", "gpio7",
                       "gpio8", "gpio9", "gpio10", "gpio11",
                       "gpio12", "gpio13", "gpio14", "gpio15";
                bias-pull-up;
            };
        };
    };

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

        gpio@0 {
            compatible = "microchip,mcp23s17";
            reg = <0>;
            gpio-controller;
            #gpio-cells = <2>;
            spi-max-frequency = <1000000>;
            microchip,spi-present-mask = /bits/ 8 <0x01>;
        };
    };