[5/5,v2] watchdog: ftwdt010: Add restart support

[Guenter Roeck]

On Mon, Oct 16, 2017 at 10:54:27PM +0200, Linus Walleij wrote:
> This enables the Faraday FTWDT010 to restart the system,
> if need be. Set the restart priority for the watchdog to
> 128.
> 
> Signed-off-by: Linus Walleij <linus.walleij at linaro.org>

Reviewed-by: Guenter Roeck <linux at roeck-us.net>

> ---
> ChangeLog v1->v2:
> - Rebased, no changes.
> ---
>  drivers/watchdog/ftwdt010_wdt.c | 18 ++++++++++++++++++
>  1 file changed, 18 insertions(+)
> 
> diff --git a/drivers/watchdog/ftwdt010_wdt.c b/drivers/watchdog/ftwdt010_wdt.c
> index 21c3ac7f557a..0be7c2db642d 100644
> --- a/drivers/watchdog/ftwdt010_wdt.c
> +++ b/drivers/watchdog/ftwdt010_wdt.c
> @@ -56,6 +56,22 @@ struct ftwdt010_wdt *to_ftwdt010_wdt(struct watchdog_device *wdd)
>  	return container_of(wdd, struct ftwdt010_wdt, wdd);
>  }
>  
> +static int ftwdt010_wdt_restart(struct watchdog_device *wdd,
> +				unsigned long action, void *data)
> +{
> +	struct ftwdt010_wdt *gwdt = to_ftwdt010_wdt(wdd);
> +	u32 enable;
> +
> +	writel(1, gwdt->base + FTWDT010_WDLOAD);
> +	writel(WDRESTART_MAGIC, gwdt->base + FTWDT010_WDRESTART);
> +	enable = WDCR_SYS_RST | WDCR_ENABLE;
> +	if (gwdt->use_extclk)
> +		enable |= WDCR_EXTCLK;
> +	writel(enable, gwdt->base + FTWDT010_WDCR);
> +
> +	return 0;
> +}
> +
>  static int ftwdt010_wdt_start(struct watchdog_device *wdd)
>  {
>  	struct ftwdt010_wdt *gwdt = to_ftwdt010_wdt(wdd);
> @@ -118,6 +134,7 @@ 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,
>  };
>  
> @@ -190,6 +207,7 @@ static int ftwdt010_wdt_probe(struct platform_device *pdev)
>  	 */
>  	gwdt->wdd.timeout = 13U;
>  	watchdog_init_timeout(&gwdt->wdd, 0, dev);
> +	watchdog_set_restart_priority(&gwdt->wdd, 128);
>  
>  	reg = readw(gwdt->base + FTWDT010_WDCR);
>  	if (reg & WDCR_ENABLE) {