Commit 16056396 authored by Matti Vaittinen's avatar Matti Vaittinen Committed by Lee Jones
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dt-bindings: battery: Voltage drop properties 

ROHM has developed a so called "zero-correction" -algorithm to improve
the fuel-gauging accuracy close to the point where battery is depleted.
This relies on battery specific "VDR" (voltage drop rate) tables, which
are measured from the battery, and which describe the voltage drop rate.
More thorough explanation about the "zero correction" and "VDR"
parameters is here:
https://lore.kernel.org/all/676253b9-ff69-7891-1f26-a8b5bb5a421b@fi.rohmeurope.com/



Document the VDR zero-correction specific battery properties used by the
BD71815, BD71828, BD72720 and some other ROHM chargers. (Note, charger
drivers aren't upstream yet).

Signed-off-by: default avatarMatti Vaittinen <mazziesaccount@gmail.com>
Reviewed-by: default avatarRob Herring (Arm) <robh@kernel.org>
Reviewed-by: default avatarLinus Walleij <linusw@kernel.org>
Link: https://patch.msgid.link/461f2840a03e0189ecd4f1a7c261014342ddee91.1765804226.git.mazziesaccount@gmail.com


Signed-off-by: default avatarLee Jones <lee@kernel.org>
parent a4330974

Documentation/devicetree/bindings/power/supply/battery.yaml

+22 −0
Original line number Diff line number Diff line
@@ -128,6 +128,21 @@ properties: 
      - description: alert when battery temperature is lower than this value

      - description: alert when battery temperature is higher than this value



  # The volt-drop* -properties describe voltage-drop for a battery, described

  # as VDROP in:

  # https://patentimages.storage.googleapis.com/6c/f5/17/c1d901c220f6a9/US20150032394A1.pdf

  volt-drop-thresh-microvolt:

    description: Threshold for starting the VDR correction

    maximum: 48000000



  volt-drop-soc-bp:

    description: Table of capacity values matching the values in VDR tables.

      The value should be given as basis points, 1/100 of a percent.



  volt-drop-temperatures-millicelsius:

    description: An array containing the temperature in milli celsius, for each

      of the VDR lookup table.



required:

  - compatible
@@ -146,6 +161,13 @@ patternProperties: 
        - description: battery capacity percent

          maximum: 100



  '^volt-drop-[0-9]-microvolt':

    description: Table of the voltage drop rate (VDR) values. Each entry in the

      table should match a capacity value in the volt-drop-soc table.

      Furthermore, the values should be obtained for the temperature given in

      volt-drop-temperatures-millicelsius table at index matching the

      number in this table's name.



additionalProperties: false



examples: