Re: [PATCH 3/4] power_supply: Introduce PSE compliant algorithm

[Jenny Tc <jenny.tc@intel.com>]

On Thu, Feb 27, 2014 at 08:47:07PM +0100, Linus Walleij wrote:
> On Wed, Feb 26, 2014 at 3:54 AM, Jenny Tc <jenny.tc@intel.com> wrote:
> 
> > The idea is to allow pluggable charging algorithms. Currently we have only one
> > charging algorithm proposed, but can have other charging algorithms (like pulse
> > charging, rule based charging etc.). Based on the platform need, the algorithms
> > can be selected. So this should be a user configurable option. I can add more
> > explanation on when to select this option.
> 
> Do you see a generic framework for pluggable algorithms on an abstracted
> level, so that it could be used for the CC/CV charging, measurement and
> temperature check algorithm that is found in e.g.
> drivers/power/abx500_chargalg.c
> drivers/power/ab8500_charger.c etc, or do you envision a set of pluggable
> algorithms for this one hardware?
> 
> I'm asking because these drivers are a massive set of code and we may
> need to start to abstract out and define library functions and frameworks
> already now before it becomes impossible to contain.

The idea of power_supply_charger driver is to move the charging logic outside of
the charger chip driver. This makes the charger chip driver as a  h/w
abstraction layer without  having any charging logic in it. power supply charger
driver invokes charging algorithm to decide the CC, CV and to stop/start
charging on different conditions (based on voltage/temperature ...). Detailed
note on using power supply charger driver can be found in
Documentation/power/power_supply_charger.txt  which is part of patch
power_supply-Introduce-generic-psy-charging-driver.patch