Re: [PATCH 3/8] Universal power supply class (was: battery class)

[Henrique de Moraes Holschuh <hmh@hmh.eng.br>]

On Fri, 04 May 2007, Shem Multinymous wrote:
> >+enum power_supply_type {
> >+       POWER_SUPPLY_TYPE_BATTERY = 0,
> >+       POWER_SUPPLY_TYPE_UPS,
> >+       POWER_SUPPLY_TYPE_AC,
> >+       POWER_SUPPLY_TYPE_USB,
> >+};
> 
> How about dumb (non-USB) DC power? Any reason to distinguish it from AC?

Hmm, if it should not be distinguished, it is better to rename AC to
something that means continuous power.  But I'd rather have it AC and DC, as
something might have both supplies separate, and you might want to
differentiate them for some (human interface) reason.  After all, USB and DC
are not really different anyway...

Anyway, what IS the difference between UPS and battery, or UPS and AC/DC for
that matter?  When should UPS be used?  If you have UPS there, should not
MGG (motor-generator group) also be provided?

Given that USB-power *is* usually also "dumb" (i.e. it doesn't do any
control signaling over the USB bus for power-control purposes), IMHO it
might be better to have just battery, AC and DC as types.  And a primary and
secondary notion too, as that is common.  It would be generic.

Or maybe I just didn't get the idea behind the "type" attribute :-)

I'd appreciate if these were documented in the text file.

-- 
  "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
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