Documentation/devicetree/bindings/watchdog/linux,wdt-gpio.yaml

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

title: GPIO-controlled Watchdog

maintainers:
  - Guenter Roeck <linux@roeck-us.net>

properties:
  compatible:
    const: linux,wdt-gpio

  gpios:
    description: gpio connection to WDT reset pin
    maxItems: 1

  hw_algo:
    description: The algorithm used by the driver.
    enum: [ level, toggle ]

  hw_margin_ms:
    description: Maximum time to reset watchdog circuit (milliseconds).
    $ref: /schemas/types.yaml#/definitions/uint32

  always-running:
    type: boolean
    description:
      If the watchdog timer cannot be disabled, add this flag to have the driver
      keep toggling the signal without a client.
      It will only cease to toggle the signal when the device is open and the
      timeout elapsed.

required:
  - compatible
  - gpios
  - hw_algo
  - hw_margin_ms

allOf:
  - $ref: watchdog.yaml#

additionalProperties: false

examples:
  - |
    #include <dt-bindings/gpio/gpio.h>
    watchdog {
        compatible = "linux,wdt-gpio";
        gpios = <&gpio3 9 GPIO_ACTIVE_LOW>;
        hw_algo = "toggle";
        hw_margin_ms = <1600>;
    };