Currently we have no means to adjust the watchdog behavior on early start up before user space has opened the device. The generic behavior among the watchdog drivers is to not start the watchdog at all (or disable it, if possible, or in case at91sam9_wdt, start a kernel timer that keeps on pinging the watchdog on behalf of user space until a watchdog daemon opens it). This unfortunately opens a time window between starting the driver and starting the user space watchdog daemon where a crash of the kernel or user space might prevent the watchdog from ever resetting the device at all. This is obviously bad on production systems. Introduce a new device tree property that, when set, changes the watchdog driver behavior in such way that there no longer is any window where crash is not caught by the watchdog. This is the third version of this patch. Previous versions of the patch were using an atmel specific property name. This patch uses a generic name instead as the functionality itself has nothing atmel related. I am also introducing watchdog.txt for describing the generic watchdog device tree bindings as there was no such file before. Timo Kokkonen (2): devicetree: Document generic watchdog properties at91sam9_wdt: Allow watchdog to reset device at early boot .../devicetree/bindings/watchdog/watchdog.txt | 19 +++++++++++++++++++ drivers/watchdog/at91sam9_wdt.c | 9 ++++++++- 2 files changed, 27 insertions(+), 1 deletion(-) create mode 100644 Documentation/devicetree/bindings/watchdog/watchdog.txt -- 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe linux-watchdog" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html