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: 2617 bytes --]

Hi,

On Tue, Jan 24, 2017 at 11:56:33AM -0800, Liam Breck wrote:
> On Sun, Jan 22, 2017 at 2:22 PM, Liam Breck <liam-RYWXG+zxWwBdeoIcmNTgJF6hYfS7NtTn@public.gmane.org> wrote:
> > I think Matt meant the following :-)
> >
> > Note: nominal-microvolt is not the correct term for termination voltage.
> > Changed to termination-microvolt
> > ---
> >
> > Documentation on battery properties that can be defined for
> > fine tuning fuel gauge state machines.
> >
> > From: Matt Ranostay <matt-sk+viVC6FLCDq+mSdOJa79kegs52MxvZ@public.gmane.org>
> > Cc: Rob Herring <robh-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
> > Cc: devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
> > Signed-off-by: Matt Ranostay <matt-sk+viVC6FLCDq+mSdOJa79kegs52MxvZ@public.gmane.org>
> > ---
> >  .../devicetree/bindings/power/supply/battery.txt   | 34 ++++++++++++++++++++++
> >  1 file changed, 34 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/power/supply/battery.txt
> >
> > diff --git a/Documentation/devicetree/bindings/power/supply/battery.txt b/Documentation/devicetree/bindings/power/supply/battery.txt
> > new file mode 100644
> > index 000000000000..398b4d622883
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/power/supply/battery.txt
> > @@ -0,0 +1,34 @@
> > +Battery Characteristics
> > +
> > +Required Properties:
> > + - compatible: Must be "fixed-battery"
> > +
> > +Optional Properties:
> > + - termination-microvolt: dead battery voltage
> > + - design-microwatt-hours: battery design energy
> > + - design-microamp-hours: battery design capacity
> 
> 
> Two more battery characteristics should be included. Battery chargers
> need them (for instance, BQ24190).
> 
> - precharge-microamps: maximum charge current during precharge
>   phase (typically 20% of battery capacity)
> 
> - termination-microamps: a charge cycle terminates when the
>   battery voltage is above recharge threshold, and the current is below
>   this setting (typically 10% of battery capacity)

I guess quite a few battery characteristics could be added. Let's
do this once we have a user for them.

> Perhaps termination-microvolt should be called terminal-microvolt or
> similar to avoid confusion.
> 
> Sebastian, did you want to include the other fields from your example?

Let's add properties once we have users for them. I just
used the stuff printed on my Nokia N900's battery as an
example :) I guess chemistry-type may actually be useful
already. I think at least some bq27xxx chips would also
work with LiPo based batteries.

-- Sebastian

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