Re: [PATCH][RFC] Proposal for a new watchdog interface using sysfs

Date: Fri Feb 14 2003 - 08:48:17 EST

On Thu, 13 Feb 2003 15:58:17 MST, Matt Porter said:

> Yes, and on embedded SoC devices we have watchdog facilities sitting
> on an internal chip bus. It would be nice to find access points in
> a uniform place on any Linux system. i.e. PCI watchdog on my x86 desktop
> is in the same place as the on-chip watchdog on my PPC44x system.
> IMHO, anything else would be a logical step backwards from accessing
> /dev/watchdog across platforms.

I admit not having thoroughly read the source to check - is the userspace API
for accessing all these chips fairly uniform and rational, so that a user
program can be reasonably sure that if stat("/dev/watchdog") returns zero, that
it knows how to deal with it? Or are they all sufficiently close to the "keep
reloading a countdown timer from userspace, and if it ever doesn't get reloaded,
kick the kernel in the seat of the pants" programming model? Of course, even
a disagreement on the units of the timer could be bad - a seconds/milliseconds
clash could result is a *real* fast lack-of-joy situation.. ;)

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

This archive was generated by hypermail 2b29 : Sat Feb 15 2003 - 22:00:54 EST