[PATCH 1/1] watchdog: aspeed: add nowayout support

[PATCH 1/1] watchdog: aspeed: add nowayout support

[Eduardo Valentin]

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>
---
 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);
-- 
2.17.1

Re: [PATCH 1/1] watchdog: aspeed: add nowayout support

[Guenter Roeck]

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);