diff --git a/drivers/watchdog/wdat_wdt.c b/drivers/watchdog/wdat_wdt.c
index 195c8c004b69d..df0865a61a702 100644
--- a/drivers/watchdog/wdat_wdt.c
+++ b/drivers/watchdog/wdat_wdt.c
@@ -344,6 +344,7 @@ static int wdat_wdt_probe(struct platform_device *pdev)
 	wdat->period = tbl->timer_period;
 	wdat->wdd.min_hw_heartbeat_ms = wdat->period * tbl->min_count;
 	wdat->wdd.max_hw_heartbeat_ms = wdat->period * tbl->max_count;
+	wdat->wdd.min_timeout = 1;
 	wdat->stopped_in_sleep = tbl->flags & ACPI_WDAT_STOPPED;
 	wdat->wdd.info = &wdat_wdt_info;
 	wdat->wdd.ops = &wdat_wdt_ops;
@@ -450,8 +451,7 @@ static int wdat_wdt_probe(struct platform_device *pdev)
 	 * watchdog properly after it has opened the device. In some cases
 	 * the BIOS default is too short and causes immediate reboot.
 	 */
-	if (timeout * 1000 < wdat->wdd.min_hw_heartbeat_ms ||
-	    timeout * 1000 > wdat->wdd.max_hw_heartbeat_ms) {
+	if (watchdog_timeout_invalid(&wdat->wdd, timeout)) {
 		dev_warn(dev, "Invalid timeout %d given, using %d\n",
 			 timeout, WDAT_DEFAULT_TIMEOUT);
 		timeout = WDAT_DEFAULT_TIMEOUT;