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Diffstat (limited to 'Documentation/devicetree/bindings/watchdog/gpio-wdt.txt')
| -rw-r--r-- | Documentation/devicetree/bindings/watchdog/gpio-wdt.txt | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/watchdog/gpio-wdt.txt b/Documentation/devicetree/bindings/watchdog/gpio-wdt.txt new file mode 100644 index 000000000..198794963 --- /dev/null +++ b/Documentation/devicetree/bindings/watchdog/gpio-wdt.txt @@ -0,0 +1,28 @@ +* GPIO-controlled Watchdog + +Required Properties: +- compatible: Should contain "linux,wdt-gpio". +- gpios: From common gpio binding; gpio connection to WDT reset pin. +- hw_algo: The algorithm used by the driver. Should be one of the + following values: + - toggle: 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. + - level: Low or high level starts counting WDT timeout, + the opposite level disables the WDT. Active level is determined + by the GPIO flags. +- hw_margin_ms: Maximum time to reset watchdog circuit (milliseconds). + +Optional Properties: +- always-running: 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. + +Example: + watchdog: watchdog { + /* ADM706 */ + compatible = "linux,wdt-gpio"; + gpios = <&gpio3 9 GPIO_ACTIVE_LOW>; + hw_algo = "toggle"; + hw_margin_ms = <1600>; + }; |