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Sender: Guenter Roeck <groeck7@gmail.com>
Message-ID: <af800c8b-8ad8-a335-0f72-ee636c02e9ef@roeck-us.net>
Date:   Fri, 11 Feb 2022 20:02:04 -0800
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Subject: Re: [PATCH 1/1] watchdog: aspeed: add nowayout support
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To:     Eduardo Valentin <eduval@amazon.com>,
        Wim Van Sebroeck <wim@linux-watchdog.org>
Cc:     Joel Stanley <joel@jms.id.au>, Andrew Jeffery <andrew@aj.id.au>,
        linux-watchdog@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org,
        linux-aspeed@lists.ozlabs.org, linux-kernel@vger.kernel.org,
        Eduardo Valentin <evalenti@kernel.org>
References: <20220212021033.2344-1-eduval@amazon.com>
From:   Guenter Roeck <linux@roeck-us.net>
In-Reply-To: <20220212021033.2344-1-eduval@amazon.com>
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On 2/11/22 18:10, Eduardo Valentin wrote:
> Add support for not stopping the watchdog
> when the userspace application quits. At
> closing of the device, the driver cannot
> determine if this was a graceful closure
> or if the app crashed. If the support
> of nowayout on this driver, the system integrator
> can select the behaviour by setting the kernel
> config and enabling it.
> 
> Cc: Wim Van Sebroeck <wim@linux-watchdog.org> (maintainer:WATCHDOG DEVICE DRIVERS)
> Cc: Guenter Roeck <linux@roeck-us.net> (maintainer:WATCHDOG DEVICE DRIVERS)
> Cc: Joel Stanley <joel@jms.id.au> (supporter:ARM/ASPEED MACHINE SUPPORT)
> Cc: Andrew Jeffery <andrew@aj.id.au> (reviewer:ARM/ASPEED MACHINE SUPPORT)
> Cc: linux-watchdog@vger.kernel.org (open list:WATCHDOG DEVICE DRIVERS)
> Cc: linux-arm-kernel@lists.infradead.org (moderated list:ARM/ASPEED MACHINE SUPPORT)
> Cc: linux-aspeed@lists.ozlabs.org (moderated list:ARM/ASPEED MACHINE SUPPORT)
> Cc: linux-kernel@vger.kernel.org (open list)
> Signed-off-by: Eduardo Valentin <eduval@amazon.com>
> Signed-off-by: Eduardo Valentin <evalenti@kernel.org>

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

> ---
>   drivers/watchdog/aspeed_wdt.c | 7 +++++++
>   1 file changed, 7 insertions(+)
> 
> diff --git a/drivers/watchdog/aspeed_wdt.c b/drivers/watchdog/aspeed_wdt.c
> index 436571b6fc79..bd06622813eb 100644
> --- a/drivers/watchdog/aspeed_wdt.c
> +++ b/drivers/watchdog/aspeed_wdt.c
> @@ -13,6 +13,11 @@
>   #include <linux/platform_device.h>
>   #include <linux/watchdog.h>
>   
> +static bool nowayout = WATCHDOG_NOWAYOUT;
> +module_param(nowayout, bool, 0);
> +MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
> +				__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
> +
>   struct aspeed_wdt {
>   	struct watchdog_device	wdd;
>   	void __iomem		*base;
> @@ -266,6 +271,8 @@ static int aspeed_wdt_probe(struct platform_device *pdev)
>   	wdt->wdd.timeout = WDT_DEFAULT_TIMEOUT;
>   	watchdog_init_timeout(&wdt->wdd, 0, dev);
>   
> +	watchdog_set_nowayout(&wdt->wdd, nowayout);
> +
>   	np = dev->of_node;
>   
>   	ofdid = of_match_node(aspeed_wdt_of_table, np);