Re: [RFC PATCH v2] watchdog: ep93xx: Use the WatchDog Timer DriverCore.

From: Wim Van Sebroeck
Date: Thu Aug 04 2011 - 16:04:50 EST


Hi All,

> > BTW, now that the driver uses watchdog core should we also select
> > WATCHDOG_CORE in the Kconfig? If it is not enabled we get:
> >
> > drivers/built-in.o: In function `ep93xx_wdt_init':
> > clkdev.c:(.init.text+0x2bd8): undefined reference to
> > `watchdog_register_device'
> > make: *** [.tmp_vmlinux1] Error 1
>
> Of course.
>
> I wasn't sure how Wim wanted to handle this. I see two ways of doing it
> in the Kconfig.
>
> 1) Each driver config option has a select WATCHDOG_CORE if it is required.
>
> Pro: all the watchdog drivers (that are available) are displayed
> Con: each driver needs to add the select if needed
> Side-effect: the WATCHDOG_CORE option could (should) be a hidden option
>
> 2) Separate the watchdog drivers into groups that need the WATCHDOG_CORE
> and those that don't then put a if WATCHDOG_CORE/endif around the ones
> that need it.
>
> Pro: keeps the Kconfig clean
> Con: the drivers that use WATCHDOG_CORE are not displayed unless the
> option is selected
> Con: defconfigs probably will need to be updated to select WATCHDOG_CORE
>
> Wim, do you have any opinion on this?

I allready discussed this with Wolfram a few weeks ago. Since we don't want
defconfigs to change, the best option is to:
1) use 'select WATCHDOG_CORE' during conversion of the drivers.
2) remove CONFIG_WATCHDOG_CORE and replace it by CONFIG_WATCHDOG in a later
stage so that the core API becomes the user-space layer for all watchdog
device drivers.This so that we can support multiple watchdogs in the
future and to make sure that we keep having a consistent user-space
interface.

Kind regards,
Wim.

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