Re: Smart Battery System Design (was: Re: Question about userspace-consumer)

[Pavel Machek <pavel@ucw.cz>]

Hi!

> > and wrt SBS, that would mean basically writing a driver for that Smart
> > Batery Charger and the Smart Battery devices creating means for some
> > entity to tell _start_charging_ based on the presence of a power source.
> 
> For me the critical thing is that we ensure that the charger won't be
> left charging at anything more than a trickle charge when there's
> nothing monitoring the battery status.  If the charger can do the SBS
> charger stuff autononmously it can look after itself (but the use of the
> regulator API becomes more questionable for those devices since the
> charger will be doing all the management of the regulators).  If the SBS
> is done entirely in software the kernel at least needs to be able to
> notice the management software exiting and clean up after it, even if
> that's all it is able to do for itself.

Please don't put basic fastcharge logic to userspace:

* you still want to fastcharge at init=/bin/bash boot

* you want to fastcharge while machine is in s2ram. See spitz. Doing
  that with userspace would be quite tricky.

-- 
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