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1# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause2%YAML 1.23---4$id: http://devicetree.org/schemas/power/supply/rohm,bd99954.yaml#5$schema: http://devicetree.org/meta-schemas/core.yaml#6 7title: ROHM BD99954 Battery charger8 9maintainers:10 - Matti Vaittinen <mazziesaccount@gmail.com>11 - Markus Laine <markus.laine@fi.rohmeurope.com>12 - Mikko Mutanen <mikko.mutanen@fi.rohmeurope.com>13 14description: |15 The ROHM BD99954 is a Battery Management LSI for 1-4 cell Lithium-Ion16 secondary battery intended to be used in space-constraint equipment such17 as Low profile Notebook PC, Tablets and other applications. BD9995418 provides a Dual-source Battery Charger, two port BC1.2 detection and a19 Battery Monitor.20 21$ref: power-supply.yaml#22 23properties:24 compatible:25 const: rohm,bd9995426#27# The battery charging profile of BD99954.28#29# Curve (1) represents charging current.30# Curve (2) represents battery voltage.31#32# The BD99954 data sheet divides charging to three phases.33# a) Trickle-charge with constant current (8).34# b) pre-charge with constant current (6)35# c) fast-charge with:36# First a constant current (5) phase (CC)37# Then constant voltage (CV) phase (after the battery voltage has reached38# target level - until charging current has dropped to termination39# level (7)40#41# V ^ ^ I42# . .43# . .44# (4)- -.- - - - - - - - - - - - - - +++++++++++++++++++++++++++.45# . / .46# . ++++++/++ - - - - - - - - - - - - -.- - (5)47# . + / + .48# . + - -- .49# . + - + .50# . +.- -: .51# . .+ +` .52# . .- + | `/ .53# . .." + .: .54# . -" + -- .55# . (2) ..." + | :- .56# . ..."" + -: .57# (3)- -.-.""- - - - -+++++++++ - - - - - - -.:- - - - - - - - - .- - (6)58# . + `:. .59# . + | -: .60# . + -: .61# . + .. .62# . (1) + | "+++- - - -.- - (7)63# -++++++++++++++- - - - - - - - - - - - - - - - - + - - - .- - (8)64# . + -65# -------------------------------------------------+++++++++-->66# | | | CC | CV |67# | --trickle-- | -pre- | ---------fast----------- |68#69# The charger uses the following battery properties70# - trickle-charge-current-microamp:71# Current used at trickle-charge phase (8 in above chart)72# minimum: 6400073# maximum: 102400074# multipleOf: 6400075# - precharge-current-microamp:76# Current used at pre-charge phase (6 in above chart)77# minimum: 6400078# maximum: 102400079# multipleOf: 6400080# - constant-charge-current-max-microamp81# Current used at fast charge constant current phase (5 in above chart)82# minimum: 6400083# maximum: 102400084# multipleOf: 6400085# - constant-charge-voltage-max-microvolt86# The constant voltage used in fast charging phase (4 in above chart)87# minimum: 256000088# maximum: 1920000089# multipleOf: 1600090# - precharge-upper-limit-microvolt91# charging mode is changed from trickle charging to pre-charging92# when battery voltage exceeds this limit voltage (3 in above chart)93# minimum: 204800094# maximum: 1920000095# multipleOf: 6400096# - re-charge-voltage-microvolt97# minimum: 256000098# maximum: 1920000099# multipleOf: 16000100# re-charging is automatically started when battry has been discharging101# to the point where the battery voltage drops below this limit102# - over-voltage-threshold-microvolt103# battery is expected to be faulty if battery voltage exceeds this limit.104# Charger will then enter to a "battery faulty" -state105# minimum: 2560000106# maximum: 19200000107# multipleOf: 16000108# - charge-term-current-microamp109# minimum: 0110# maximum: 1024000111# multipleOf: 64000112# a charge cycle terminates when the battery voltage is above recharge113# threshold, and the current is below this setting (7 in above chart)114# See also Documentation/devicetree/bindings/power/supply/battery.yaml115 116 reg:117 maxItems: 1118 119 interrupts:120 maxItems: 1121 122 monitored-battery:123 description:124 phandle of battery characteristics devicetree node125 126 rohm,vsys-regulation-microvolt:127 description: system specific lower limit for system voltage.128 minimum: 2560000129 maximum: 19200000130 multipleOf: 64000131 132 rohm,vbus-input-current-limit-microamp:133 description: system specific VBUS input current limit (in microamps).134 minimum: 32000135 maximum: 16352000136 multipleOf: 32000137 138 rohm,vcc-input-current-limit-microamp:139 description: system specific VCC/VACP input current limit (in microamps).140 minimum: 32000141 maximum: 16352000142 multipleOf: 32000143 144required:145 - compatible146 147additionalProperties: false148 149examples:150 - |151 i2c {152 #address-cells = <1>;153 #size-cells = <0>;154 charger@9 {155 compatible = "rohm,bd99954";156 monitored-battery = <&battery>;157 reg = <0x9>;158 interrupt-parent = <&gpio1>;159 interrupts = <29 8>;160 rohm,vsys-regulation-microvolt = <8960000>;161 rohm,vbus-input-current-limit-microamp = <1472000>;162 rohm,vcc-input-current-limit-microamp = <1472000>;163 };164 };165