[ltp] Battery capacity updates under Linux

[Henrique de Moraes Holschuh]

On Tue, 24 Oct 2006, Shem Multinymous wrote:
> >> Is this value updated when the battery is used only under Linux?

No, it is either a BEC (battery embedded controller :p) function, or
something the ThinkPad EC takes care of by itself.  It is very likely the
former, as the data is stored in the battery pack (swap packs, if you doubt
me :p).

> >> What are the conditions for updating tihs value?

Charge the battery until it is 100% full and stops charging by itself.

> Yes, the information is computed and by battery's internal controller.
> But it might require some specific command from the host (e.g., "fully
> discharge the battery") to initiate the measurement. The Smart Battery
> Data Specification says nothing about this.

No such weirdness. It does the sensible thing and just works.

I verified this last time I needed to update the BIOS.  The ThinkPad was
charged under EC control (i.e. I plugged it into AC when the battery was
about half charged, didn't turn it on, and waited until the battery led
stayed in solid green state.  The thinkpad was powered off for the entire
time).  I always keep an eye on the last full capacity, because I am miffed
that my 6-cell is at ~42500 already.

-- 
  "One disk to rule them all, One disk to find them. One disk to bring
  them all and in the darkness grind them. In the Land of Redmond
  where the shadows lie." -- The Silicon Valley Tarot
  Henrique Holschuh