Commit 40efc43e authored by Ziyan Fu's avatar Ziyan Fu Committed by Wim Van Sebroeck
Browse files

watchdog: iTCO_wdt: Report error if timeout configuration fails 



The driver probes with the invalid timeout value when
'iTCO_wdt_set_timeout()' fails, as its return value is not checked. In
this case, when executing "wdctl", we may get:

Device:        /dev/watchdog0
Timeout:       30 seconds
Timeleft:      613 seconds

The timeout value is the value of "heartbeat" or "WATCHDOG_TIMEOUT", and
the timeleft value is calculated from the register value we actually read
(0xffff) by masking with 0x3ff and converting ticks to seconds (* 6 / 10).

Add error handling to return the failure code if 'iTCO_wdt_set_timeout()'
fails, ensuring the driver probe fails and prevents invalid operation.

Signed-off-by: default avatarZiyan Fu <fuzy5@lenovo.com>
Reviewed-by: default avatarGuenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20250704073518.7838-1-13281011316@163.com


Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
Signed-off-by: default avatarWim Van Sebroeck <wim@linux-watchdog.org>
parent 3b3643e1

drivers/watchdog/iTCO_wdt.c

+5 −1
Original line number Diff line number Diff line
@@ -577,7 +577,11 @@ static int iTCO_wdt_probe(struct platform_device *pdev) 
	/* Check that the heartbeat value is within it's range;

	   if not reset to the default */

	if (iTCO_wdt_set_timeout(&p->wddev, heartbeat)) {

		iTCO_wdt_set_timeout(&p->wddev, WATCHDOG_TIMEOUT);

		ret = iTCO_wdt_set_timeout(&p->wddev, WATCHDOG_TIMEOUT);

		if (ret != 0) {

			dev_err(dev, "Failed to set watchdog timeout (%d)\n", WATCHDOG_TIMEOUT);

			return ret;

		}

		dev_info(dev, "timeout value out of range, using %d\n",

			WATCHDOG_TIMEOUT);

		heartbeat = WATCHDOG_TIMEOUT;