watchdog: s3c2410: Fail probe if can't find valid timeout

Driver can't work properly if there no valid timeout was found in
s3c2410wdt_set_heartbeat(). Ideally, that function should be reworked in
a way that it's always able to find some valid timeout. As a temporary
solution let's for now just fail the driver probe in case the valid
timeout can't be found in s3c2410wdt_set_heartbeat() function.

Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Suggested-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20211107202943.8859-4-semen.protsenko@linaro.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

drivers/watchdog/s3c2410_wdt.c

@@ -515,7 +515,6 @@ static int s3c2410wdt_probe(struct platform_device *pdev)
 	struct s3c2410_wdt *wdt;
 	struct resource *wdt_irq;
 	unsigned int wtcon;
-	int started = 0;
 	int ret;
 
 	wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);
@@ -581,15 +580,15 @@ static int s3c2410wdt_probe(struct platform_device *pdev)
 	ret = s3c2410wdt_set_heartbeat(&wdt->wdt_device,
 					wdt->wdt_device.timeout);
 	if (ret) {
-		started = s3c2410wdt_set_heartbeat(&wdt->wdt_device,
-					S3C2410_WATCHDOG_DEFAULT_TIME);
-
-		if (started == 0)
-			dev_info(dev,
-				 "tmr_margin value out of range, default %d used\n",
+		ret = s3c2410wdt_set_heartbeat(&wdt->wdt_device,
+					       S3C2410_WATCHDOG_DEFAULT_TIME);
+		if (ret == 0) {
+			dev_warn(dev, "tmr_margin value out of range, default %d used\n",
 				 S3C2410_WATCHDOG_DEFAULT_TIME);
-		else
-			dev_info(dev, "default timer value is out of range, cannot start\n");
+		} else {
+			dev_err(dev, "failed to use default timeout\n");
+			goto err_cpufreq;
+		}
 	}
 
 	ret = devm_request_irq(dev, wdt_irq->start, s3c2410wdt_irq, 0,
@@ -613,10 +612,10 @@ static int s3c2410wdt_probe(struct platform_device *pdev)
 	if (ret < 0)
 		goto err_unregister;
 
-	if (tmr_atboot && started == 0) {
+	if (tmr_atboot) {
 		dev_info(dev, "starting watchdog timer\n");
 		s3c2410wdt_start(&wdt->wdt_device);
-	} else if (!tmr_atboot) {
+	} else {
 		/* if we're not enabling the watchdog, then ensure it is
 		 * disabled if it has been left running from the bootloader
 		 * or other source */