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