Re: [PATCH v4 2/8] devicetree: power: add battery state machine documentation

[Sebastian Reichel <sre-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>]

[-- Attachment #1: Type: text/plain, Size: 2121 bytes --]

Hi,

On Sun, Jan 29, 2017 at 03:32:10PM -0800, Liam Breck wrote:
> On Sun, Jan 29, 2017 at 10:06 AM, Sebastian Reichel <sre-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org> wrote:
> > On Sun, Jan 22, 2017 at 02:22:12PM -0800, Liam Breck wrote:
> ...
> >> +Batteries must be referenced by chargers and/or fuel-gauges
> >> +using a phandle. The phandle's property should be named
> >> +"monitored-battery".
> >> +
> >> +Example:
> >> +
> >> +     bat: battery {
> >> +             compatible = "fixed-battery";
> >> +             terminate-microvolt = <3700000>;
> >> +             design-microwatt-hours = <5290000>;
> >> +             design-microamp-hours = <1430000>;
> >> +     };
> >> +
> >> +     charger: charger@0 {
> >> +             ....
> >> +             monitored-battery = <&bat>;
> >> +             ...
> >> +     };
> >> +
> >> +     fuel_gauge: fuel_gauge@0 {
> >> +             ....
> >> +             monitored-battery = <&bat>;
> >> +             ...
> >> +     };
> >
> > The charger stuff does does not integrate well with
> > pre-existing support for power-supplies property
> > described in
> > Documentation/devicetree/bindings/power/supply/power_supply.txt
> >
> > I think the proper chain would be:
> >
> > bat: battery {
> >         compatible = "fixed-battery";
> >         terminate-microvolt = <3700000>;
> >         design-microwatt-hours = <5290000>;
> >         design-microamp-hours = <1430000>;
> > };
> >
> > fuel_gauge: fuel_gauge@0 {
> >         ...
> >         monitored-battery = <&bat>;
> >         power-supplies = <&charger>;
> >         ...
> > };
> >
> > charger: charger@0 {
> >         ...
> > };
> >
> > I added the power-supplies node to the fuel-gauge instead of the battery,
> > since fuel-gauge + fixed-battery is basically a smart battery.
> 
> BQ24190 charger will need other params from a battery node. How does
> it get them in this scenario?

It should be able to get all required properties from the bq27xxx.
Otherwise supporting smart batteries is impossible. What properties
do you need?

-- Sebastian

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]