[Nut-upsdev] [nut-commits] svn commit r1041 - in trunk: . drivers

[Arnaud Quette]

2007/8/11, Arjen de Korte <nut+devel at de-korte.org>:
>
> >> - If the UPS sends reports on the interrupt pipeline, we consider that
> >> enough proof that it is still there. At the same time, we assume that it
> >> keeps us informed of *all* important status changes, so that doing a
> >> HU_WALKMODE_QUICK_UPDATE is redundant then.
> > This latter assumption is probably not valid in all cases. For
> > example, since the interrupt value of
> > UPS.PowerSummary.BelowRemainingCapacityLimit was broken on Belkin, we
> > decided to go with UPS.BELKINStatus.BELKINBatteryStatus instead, which
> > is a variable that is *not* sent on the interrupt pipeline.
> >
> > In general, not every UPS that uses the interrupt pipeline can be
> > trusted to send all important values on it.
>
> I was already afraid of that, so I decided to explicitly mention this in
> the ChangeLog. You have a good point here. But so far, the only subdriver
> that uses the HU_WALKMODE_QUICK_UPDATE (by setting HU_FLAG_QUICK_POLL on
> relevant elements) is mge-hid. So for all but that one, the behaviour
> remains the same. I know that at least my Evolution 650 is quite verbose
> on the interrupt pipeline when something important happens (it will push
> even more parameters than we sollicit from it with a
> HU_WALKMODE_QUICK_UPDATE), so apparently MGE uses it (though I have not
> checked other models of course).
>
> In order to make the HU_WALKMODE_QUICK_UPDATE more useful, we probably
> need to set HU_FLAG_QUICK_POLL on "usb.status" elements for more
> subdrivers. For instance, on the "ups.status" for
> UPS.BELKINStatus.BELKINPowerStatus and
> UPS.BELKINStatus.BELKINBatteryStatus in belkin-hid.c (all of them). I'm
> reluctant to do this, since I can't test if this increased polling of
> these items doens't break these subdrivers.

a quick note about HU_WALKMODE_*_UPDATE: this is a mess! really!
at first, it was intended to only query the main variables, when the
interrupt support wasn't yet implemented. It was interesting to lower
a bit the USB communication on the UPS side, since as Arjen told, the
UPS was already generating verbose outputs.

the situation has evolved since that day...

btw, all MGE units support interrupt generation (old / new, shut /
usb, I'm not sure about the older UTalk though). This only problem was
some USB DOS on older low end models when flooded (as detailed above).

Arnaud
-- 
Free Software Developer - http://arnaud.quette.free.fr/
Debian Developer - http://people.debian.org/~aquette/
Network UPS Tools (NUT) Project Leader - http://www.networkupstools.org/
Ubuntu Media Center (UMC) Project Leader - https://launchpad.net/~umc-team