Re: Stopping watchdog in watchdog driver remove functions

[Guenter Roeck]

On 01/01/2017 03:14 AM, Wim Van Sebroeck wrote:
> Hi Guenter,
>
> > I noticed that several watchdog drivers stop the watchdog in trhe driver
> > remove function.
> > A non-exhaustive list of drivers doing that is
> >
> > 	drivers/watchdog/bcm7038_wdt.c
> > 	drivers/watchdog/cadence_wdt.c
> > 	drivers/watchdog/imgpdc_wdt.c
> > 	drivers/watchdog/jz4740_wdt.c
> > 	drivers/watchdog/kempld_wdt.c
> > 	drivers/watchdog/max77620_wdt.c
> > 	drivers/watchdog/moxart_wdt.c
> > 	drivers/watchdog/sama5d4_wdt.c
> > 	drivers/watchdog/tangox_wdt.c
> > 	drivers/watchdog/tegra_wdt.c
> >
> > Since a watchdog has to be closed for its driver to be removable, one
> > situation
> > where a watchdog is still running on unload is where the watchdog was
> > opened but
> > not closed properly (eg by killing the watchdog application, or if the
> > 'nowayout'
> > flag is set).
> >
> > Given that, does it even make sense to stop the watchdog in the remove
> > function ?
> > Should it even be permitted ?
>
> > From an API point of view: if WDIOF_MAGICCLOSE is being used then the watchdog
> _SHOULD_ continue to run when the watchdog was not properly closed (which
> normally also results in a reboot of the system).
> if WDIOF_MAGICCLOSE is not being used then closing the watchdog device means
> that the driver needs to stop the watchdog.
All the above have WDIOF_MAGICCLOSE set. Does that mean they should not stop
the watchdog on remove ?

Happy new year everyone !

Guenter