* GPIO-controlled Watchdog
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Required Properties:
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- compatible: Should contain "linux,wdt-gpio".
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- gpios: From common gpio binding; gpio connection to WDT reset pin.
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- hw_algo: The algorithm used by the driver. Should be one of the
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following values:
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- toggle: Either a high-to-low or a low-to-high transition clears
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the WDT counter. The watchdog timer is disabled when GPIO is
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left floating or connected to a three-state buffer.
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- level: Low or high level starts counting WDT timeout,
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the opposite level disables the WDT. Active level is determined
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by the GPIO flags.
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- hw_margin_ms: Maximum time to reset watchdog circuit (milliseconds).
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Optional Properties:
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- always-running: If the watchdog timer cannot be disabled, add this flag to
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have the driver keep toggling the signal without a client. It will only cease
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to toggle the signal when the device is open and the timeout elapsed.
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Example:
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watchdog: watchdog {
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/* ADM706 */
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compatible = "linux,wdt-gpio";
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gpios = <&gpio3 9 GPIO_ACTIVE_LOW>;
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hw_algo = "toggle";
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hw_margin_ms = <1600>;
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};
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