Re: [PATCH 6/6] watchdog: tangox_wdt: test clock rate to avoid division by 0

From: Guenter Roeck
Date: Wed Mar 02 2016 - 23:26:25 EST


On Wed, Mar 02, 2016 at 11:33:37PM +0100, Wolfram Sang wrote:
> From: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
>
> The clk API may return 0 on clk_get_rate, so we should check the result before
> using it as a divisor.
>
> Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
> ---
>
> Should go individually via subsystem tree.
>
> drivers/watchdog/tangox_wdt.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/drivers/watchdog/tangox_wdt.c b/drivers/watchdog/tangox_wdt.c
> index 709c1ed6fd79b9..cc702718ae4dbb 100644
> --- a/drivers/watchdog/tangox_wdt.c
> +++ b/drivers/watchdog/tangox_wdt.c
> @@ -139,6 +139,8 @@ static int tangox_wdt_probe(struct platform_device *pdev)
> return err;
>
> dev->clk_rate = clk_get_rate(dev->clk);
> + if (!dev->clk_rate)
> + return -EINVAL;

May be a nitpick, but clk_disable_unprepare() is missing.

Guenter

>
> dev->wdt.parent = &pdev->dev;
> dev->wdt.info = &tangox_wdt_info;
> --
> 2.7.0
>