PMU questions

Colin Leroy colin at colino.net
Tue Oct 19 07:20:04 EST 2004


Hi everyone,

I'm at a loss with a PMU-related problem... Basically something happened
and my iBook (G4 14") battery now thinks it can last only 30 minutes.
It used to be 3+ hours. I don't really know what happened.

After having tried to recalibrate it using Apple's secret-code
(shift-control-option-power) and cycling it, things only got worse. I
suspect it's due to the fact Linux doesn't put the laptop to sleep
when the battery empties, but I don't have an OS X partition nor can
backup 40GB...
So I'm about to buy a new battery, but I fear the stupidity of the PMU
will make it work as bad as the current one. So, here are the questions
I have, I think people there will be more apt to answer me than any
hotliner I could get at Apple:
- is the max_charge field displayed in /proc/pmu/battery_0 stored in the
PMU itself, or in the battery ? If I get a new battery and can't
calibrate it, I do hope it's stored in the battery, but I'm really not
sure about that.
- Would there be any way to overwrite this value by using some hack in
via-pmu.c, or is that PMU a real black-box ? If it's writable, does
there exist code somewhere to do that, or some doc I could use to write
it ?
- If there are people on this list with an iBook g4 14", could you tell
me what's your max_charge value is ? mine is now 507... :-/

Many thanks in advance...
-- 
Colin



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