Re: [PATCH v2] watchdog: ftwdt010_wdt: implement _restart() function

[Guenter Roeck <linux@xxxxxxxxxxxx>]

On 8/27/22 07:24, Sergei Antonov wrote:
> Implement ftwdt010_wdt_restart(). It enables watchdog with timeout = 0
> and disabled IRQ. Since it needs code similar to ftwdt010_wdt_start(),
> add a new function ftwdt010_enable() and move common code there.
>
> v1 -> v2:
> Do not let IRQ trigger when restarting.
> Add a helper function ftwdt010_enable().

Version history should be after ---. Otherwise

Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>


> Suggested-by: Guenter Roeck <linux@xxxxxxxxxxxx>
> Signed-off-by: Sergei Antonov <saproj@xxxxxxxxx>
> ---
>   drivers/watchdog/ftwdt010_wdt.c | 23 +++++++++++++++++++----
>   1 file changed, 19 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/watchdog/ftwdt010_wdt.c b/drivers/watchdog/ftwdt010_wdt.c
> index 21dcc7765688..0a5bbfd2823f 100644
> --- a/drivers/watchdog/ftwdt010_wdt.c
> +++ b/drivers/watchdog/ftwdt010_wdt.c
> @@ -47,21 +47,28 @@ struct ftwdt010_wdt *to_ftwdt010_wdt(struct watchdog_device *wdd)
>   	return container_of(wdd, struct ftwdt010_wdt, wdd);
>   }
>   
> -static int ftwdt010_wdt_start(struct watchdog_device *wdd)
> +static void ftwdt010_enable(struct ftwdt010_wdt *gwdt,
> +			    unsigned int timeout,
> +			    bool need_irq)
>   {
> -	struct ftwdt010_wdt *gwdt = to_ftwdt010_wdt(wdd);
>   	u32 enable;
>   
> -	writel(wdd->timeout * WDT_CLOCK, gwdt->base + FTWDT010_WDLOAD);
> +	writel(timeout * WDT_CLOCK, gwdt->base + FTWDT010_WDLOAD);
>   	writel(WDRESTART_MAGIC, gwdt->base + FTWDT010_WDRESTART);
>   	/* set clock before enabling */
>   	enable = WDCR_CLOCK_5MHZ | WDCR_SYS_RST;
>   	writel(enable, gwdt->base + FTWDT010_WDCR);
> -	if (gwdt->has_irq)
> +	if (need_irq)
>   		enable |= WDCR_WDINTR;
>   	enable |= WDCR_ENABLE;
>   	writel(enable, gwdt->base + FTWDT010_WDCR);
> +}
>   
> +static int ftwdt010_wdt_start(struct watchdog_device *wdd)
> +{
> +	struct ftwdt010_wdt *gwdt = to_ftwdt010_wdt(wdd);
> +
> +	ftwdt010_enable(gwdt, wdd->timeout, gwdt->has_irq);
>   	return 0;
>   }
>   
> @@ -93,6 +100,13 @@ static int ftwdt010_wdt_set_timeout(struct watchdog_device *wdd,
>   	return 0;
>   }
>   
> +static int ftwdt010_wdt_restart(struct watchdog_device *wdd,
> +				unsigned long action, void *data)
> +{
> +	ftwdt010_enable(to_ftwdt010_wdt(wdd), 0, false);
> +	return 0;
> +}
> +
>   static irqreturn_t ftwdt010_wdt_interrupt(int irq, void *data)
>   {
>   	struct ftwdt010_wdt *gwdt = data;
> @@ -107,6 +121,7 @@ static const struct watchdog_ops ftwdt010_wdt_ops = {
>   	.stop		= ftwdt010_wdt_stop,
>   	.ping		= ftwdt010_wdt_ping,
>   	.set_timeout	= ftwdt010_wdt_set_timeout,
> +	.restart	= ftwdt010_wdt_restart,
>   	.owner		= THIS_MODULE,
>   };
>