watchdog: tangox_wdt: test clock rate to avoid division by 0
The clk API may return 0 on clk_get_rate, so we should check the result before
using it as a divisor. For this, refactor the code to use a central
error path.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
diff --git a/drivers/watchdog/tangox_wdt.c b/drivers/watchdog/tangox_wdt.c
index 709c1ed..cfbed7e 100644
--- a/drivers/watchdog/tangox_wdt.c
+++ b/drivers/watchdog/tangox_wdt.c
@@ -139,6 +139,10 @@
return err;
dev->clk_rate = clk_get_rate(dev->clk);
+ if (!dev->clk_rate) {
+ err = -EINVAL;
+ goto err;
+ }
dev->wdt.parent = &pdev->dev;
dev->wdt.info = &tangox_wdt_info;
@@ -171,10 +175,8 @@
}
err = watchdog_register_device(&dev->wdt);
- if (err) {
- clk_disable_unprepare(dev->clk);
- return err;
- }
+ if (err)
+ goto err;
platform_set_drvdata(pdev, dev);
@@ -187,6 +189,10 @@
dev_info(&pdev->dev, "SMP86xx/SMP87xx watchdog registered\n");
return 0;
+
+ err:
+ clk_disable_unprepare(dev->clk);
+ return err;
}
static int tangox_wdt_remove(struct platform_device *pdev)