I have an intel platfrom (Alder Lake N50) and I’m trying to use the chipset watchdog hardware.

My kernel is configured to have the iTCO_wdt module, when I insert it, the device is detected and /dev/watchdog is created:
TCO_wdt iTCO_wdt: Found a Intel PCH TCO device (Version=6, TCOBASE=0x0400) iTCO_wdt: initialized. heartbeat=120 sec (nowayout=0)

however, no process pings /dev/watchdog (checked with lsof), and the system never reboots.

I tried this: cat >> /dev/watchdog

and every time I get the message:
watchdog0: watchdog did not stop!

I’ve also noticed this message every time I reboot my system:
watchdog: watchdog0: watchdog did not stop! systemd-shutdown[1]: Using hardware watchdog 'iTCO_wdt', version 0, device /dev/watchdog0 systemd-shutdown[1]: Watchdog running with a timeout of 10min.
where do these ’10min’ come from ? and how can i update it and kill the process that refresh the watchdog to test if the system reboot ?

TY

I tried: cat >> /dev/watchdog
I expected that the system will reboot after 120s