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

69 lines
1.7 KiB
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>
- Robert Marko <robert.marko@sartura.hr>
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.
oneOf:
- description:
Either a high-to-low or a low-to-high transition clears the WDT counter.
The watchdog timer is disabled when GPIO is left floating or connected
to a three-state buffer.
const: toggle
- description:
Low or high level starts counting WDT timeout, the opposite level
disables the WDT.
Active level is determined by the GPIO flags.
const: level
hw_margin_ms:
description: Maximum time to reset watchdog circuit (milliseconds).
$ref: /schemas/types.yaml#/definitions/uint32
minimum: 2
maximum: 65535
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#
unevaluatedProperties: 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>;
};