1*c66ec88fSEmmanuel Vadot* GPIO-controlled Watchdog
2*c66ec88fSEmmanuel Vadot
3*c66ec88fSEmmanuel VadotRequired Properties:
4*c66ec88fSEmmanuel Vadot- compatible: Should contain "linux,wdt-gpio".
5*c66ec88fSEmmanuel Vadot- gpios: From common gpio binding; gpio connection to WDT reset pin.
6*c66ec88fSEmmanuel Vadot- hw_algo: The algorithm used by the driver. Should be one of the
7*c66ec88fSEmmanuel Vadot  following values:
8*c66ec88fSEmmanuel Vadot  - toggle: Either a high-to-low or a low-to-high transition clears
9*c66ec88fSEmmanuel Vadot    the WDT counter. The watchdog timer is disabled when GPIO is
10*c66ec88fSEmmanuel Vadot    left floating or connected to a three-state buffer.
11*c66ec88fSEmmanuel Vadot  - level: Low or high level starts counting WDT timeout,
12*c66ec88fSEmmanuel Vadot    the opposite level disables the WDT. Active level is determined
13*c66ec88fSEmmanuel Vadot    by the GPIO flags.
14*c66ec88fSEmmanuel Vadot- hw_margin_ms: Maximum time to reset watchdog circuit (milliseconds).
15*c66ec88fSEmmanuel Vadot
16*c66ec88fSEmmanuel VadotOptional Properties:
17*c66ec88fSEmmanuel Vadot- always-running: If the watchdog timer cannot be disabled, add this flag to
18*c66ec88fSEmmanuel Vadot  have the driver keep toggling the signal without a client. It will only cease
19*c66ec88fSEmmanuel Vadot  to toggle the signal when the device is open and the timeout elapsed.
20*c66ec88fSEmmanuel Vadot
21*c66ec88fSEmmanuel VadotExample:
22*c66ec88fSEmmanuel Vadot	watchdog: watchdog {
23*c66ec88fSEmmanuel Vadot		/* ADM706 */
24*c66ec88fSEmmanuel Vadot		compatible = "linux,wdt-gpio";
25*c66ec88fSEmmanuel Vadot		gpios = <&gpio3 9 GPIO_ACTIVE_LOW>;
26*c66ec88fSEmmanuel Vadot		hw_algo = "toggle";
27*c66ec88fSEmmanuel Vadot		hw_margin_ms = <1600>;
28*c66ec88fSEmmanuel Vadot	};
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