[RFC v4 13/26] watchdog: renesas_wdt: Add restart handler

[Geert Uytterhoeven]

Hi Fabrizio,

On Wed, Jan 31, 2018 at 7:24 PM, Fabrizio Castro
<fabrizio.castro at bp.renesas.com> wrote:
> On iWave's boards iwg20d and iwg22d the only way to reboot the system is
> by means of the watchdog.
> This patch adds a restart handler to rwdt_ops, and also makes sure we
> keep its priority to a medium level, in order to not override other more
> effective handlers.
>
> Signed-off-by: Fabrizio Castro <fabrizio.castro at bp.renesas.com>
> Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram at bp.renesas.com>

> --- a/drivers/watchdog/renesas_wdt.c
> +++ b/drivers/watchdog/renesas_wdt.c
> @@ -118,6 +136,7 @@ static const struct watchdog_ops rwdt_ops = {
>         .stop = rwdt_stop,
>         .ping = rwdt_init_timeout,
>         .get_timeleft = rwdt_get_timeleft,
> +       .restart = rwdt_restart,
>  };
>
>  static int rwdt_probe(struct platform_device *pdev)
> @@ -176,6 +195,7 @@ static int rwdt_probe(struct platform_device *pdev)
>         platform_set_drvdata(pdev, priv);
>         watchdog_set_drvdata(&priv->wdev, priv);
>         watchdog_set_nowayout(&priv->wdev, nowayout);
> +       watchdog_set_restart_priority(&priv->wdev, 128);

Given we want to reboot R-Car Gen2 boards equipped with a suitable PMIC
(e.g. DA9063) using that PMIC, I think the priority should be lower (0?),
cfr.

 *   0:   use watchdog's restart function as last resort, has limited restart
 *        capabilies
 *   128: default restart handler, use if no other handler is expected to be
 *        available and/or if restart is sufficient to restart the entire system
 *   255: preempt all other handlers

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org

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when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds