From: Arnd Bergmann <arnd@arndb.de>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Subject: Re: [PATCH 7/10 v2] Generic Watchdog Timer Driver
Date: Sun, 19 Jun 2011 13:25:17 +0200
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Cc: Wim Van Sebroeck <wim@iguana.be>, LKML <linux-kernel@vger.kernel.org>,
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On Sunday 19 June 2011 12:03:28 Alan Cox wrote:
> > >         /* Register the watchdog timer device */
> > >         res = watchdog_register_device(&wdt_dev);
> > 
> > Why is this a feature of the individual drivers and not of the core?
> 
> It's a hardware dependant feature - some watchdogs cannot be stopped once
> initialized.

Ah, I see. OTOH, 80 of the 107 watchdogs in the kernel do provide it as a
module option, which indicates that there is some room for consolidation,
even if it might not be appropriate for every one of them.

> > Maybe it can be in both, so existing drivers don't need to change the user
> > interface, but new drivers don't have to provide the option individually
> > when you can simply set it for the base module.
> 
> Then you'd need an additional interface to specify which watchdog as soon
> as we support multiple watchdogs.

You can always have multiple ways of setting nowayout -- hardware requirements,
global module option, local module option, and a new ioctl command -- but
what is being used is then the logical OR of all of them.

	Arnd
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