Re: [PATCH v2 6/4] watchdog: omap: allow to keep timer running at probe time

[Guenter Roeck <linux@roeck-us.net>]

On 04/29/2015 11:38 AM, Uwe Kleine-König wrote:
> From: unknown author <unknown.author@example.com>
>
> On some machines it might be desirable to keep the watchdog that is
> started in the boot ROM running until userspace starts stroking it to be
> able to handle boot failures.
>
> To not introduce regressions for users not caring about the watchdog
> keep the previous behaviour of disabling the watchdog in the probe
> function unless a module parameter stop_at_probe is set to false.
>
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

Uwe,

would this address the problem you are tryng to solve ?

http://www.spinics.net/lists/arm-kernel/msg413658.html

Guenter

> ---
>   drivers/watchdog/omap_wdt.c | 12 +++++++++---
>   1 file changed, 9 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/watchdog/omap_wdt.c b/drivers/watchdog/omap_wdt.c
> index d7619dd7c1ca..5525afadf0ec 100644
> --- a/drivers/watchdog/omap_wdt.c
> +++ b/drivers/watchdog/omap_wdt.c
> @@ -53,6 +53,11 @@ static unsigned timer_margin;
>   module_param(timer_margin, uint, 0);
>   MODULE_PARM_DESC(timer_margin, "initial watchdog timeout (in seconds)");
>
> +static bool stop_at_probe = true;
> +module_param(stop_at_probe, bool, 0);
> +MODULE_PARM_DESC(stop_at_probe,
> +		 "Watchdog is stopped at probe time (default=true)");
> +
>   #define to_omap_wdt_dev(_wdog)	container_of(_wdog, struct omap_wdt_dev, wdog)
>
>   struct omap_wdt_dev {
> @@ -254,7 +259,8 @@ static int omap_wdt_probe(struct platform_device *pdev)
>   			wdev->wdog.bootstatus = WDIOF_CARDRESET;
>   	}
>
> -	omap_wdt_disable(wdev);
> +	if (stop_at_probe)
> +		omap_wdt_disable(wdev);
>
>   	ret = watchdog_register_device(&wdev->wdog);
>   	if (ret) {
> @@ -262,9 +268,9 @@ static int omap_wdt_probe(struct platform_device *pdev)
>   		return ret;
>   	}
>
> -	pr_info("OMAP Watchdog Timer Rev 0x%02x: initial timeout %d sec\n",
> +	pr_info("OMAP Watchdog Timer Rev 0x%02x: initial timeout %d sec, %sstopped\n",
>   		readl_relaxed(wdev->base + OMAP_WATCHDOG_REV) & 0xFF,
> -		wdev->wdog.timeout);
> +		wdev->wdog.timeout, stop_at_probe ? "" : "not ");
>
>   	pm_runtime_put_sync(wdev->dev);
>
>