On Sun, Jan 22, 2017 at 02:22:12PM -0800, Liam Breck wrote:
> I think Matt meant the following :-)
>
> Note: nominal-microvolt is not the correct term for termination voltage.
> Changed to termination-microvolt
That's right.
> Documentation on battery properties that can be defined for
> fine tuning fuel gauge state machines.
Maybe:
Documentation for batteries, that cannot identify themself. The
information is required by fuel-gauge and charger chips for
proper handling of the battery.
> From: Matt Ranostay <matt@ranostay.consulting>
> Cc: Rob Herring <robh@xxxxxxxxxx>
> Cc: devicetree@xxxxxxxxxxxxxxx
> Signed-off-by: Matt Ranostay <matt@ranostay.consulting>
> ---
> .../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
I think this is not named optimally, since it's not
clear if its related to charging.
> + - design-microwatt-hours: battery design energy
> + - design-microamp-hours: battery design capacity
> +
> +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.
-- Sebastian
Attachment:
signature.asc
Description: PGP signature
