Sender: Guenter Roeck <groeck7@gmail.com>
Subject: Re: [PATCH] watchdog: msc313e: Check if the WDT was running at boot
To:     Daniel Palmer <daniel@0x0f.com>, wim@linux-watchdog.org,
        linux-watchdog@vger.kernel.org
Cc:     romain.perier@gmail.com, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org
References: <20211228073427.2443174-1-daniel@0x0f.com>
From:   Guenter Roeck <linux@roeck-us.net>
Message-ID: <1f60c5ac-b262-2b8f-6bf1-c1c7f2b20699@roeck-us.net>
Date:   Tue, 28 Dec 2021 08:06:09 -0800
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On 12/27/21 11:34 PM, Daniel Palmer wrote:
> Check if the WDT was running at boot and set the running
> flag if it was. This prevents the system from getting
> rebooted if the userland daemon doesn't take over soon enough
> or there isn't a userland daemon at all.
> 
> Signed-off-by: Daniel Palmer <daniel@0x0f.com>

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

> ---
>   drivers/watchdog/msc313e_wdt.c | 4 ++++
>   1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/watchdog/msc313e_wdt.c b/drivers/watchdog/msc313e_wdt.c
> index 0d497aa0fb7d..90171431fc59 100644
> --- a/drivers/watchdog/msc313e_wdt.c
> +++ b/drivers/watchdog/msc313e_wdt.c
> @@ -120,6 +120,10 @@ static int msc313e_wdt_probe(struct platform_device *pdev)
>   	priv->wdev.max_timeout = U32_MAX / clk_get_rate(priv->clk);
>   	priv->wdev.timeout = MSC313E_WDT_DEFAULT_TIMEOUT;
>   
> +	/* If the period is non-zero the WDT is running */
> +	if (readw(priv->base + REG_WDT_MAX_PRD_L) | (readw(priv->base + REG_WDT_MAX_PRD_H) << 16))
> +		set_bit(WDOG_HW_RUNNING, &priv->wdev.status);
> +
>   	watchdog_set_drvdata(&priv->wdev, priv);
>   
>   	watchdog_init_timeout(&priv->wdev, timeout, dev);
>