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| -rw-r--r-- | Documentation/devicetree/bindings/power/supply/rohm,bd99954.yaml | 155 |
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diff --git a/Documentation/devicetree/bindings/power/supply/rohm,bd99954.yaml b/Documentation/devicetree/bindings/power/supply/rohm,bd99954.yaml new file mode 100644 index 000000000000..7e0f73a898c7 --- /dev/null +++ b/Documentation/devicetree/bindings/power/supply/rohm,bd99954.yaml @@ -0,0 +1,155 @@ +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/power/supply/rohm,bd99954.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: ROHM BD99954 Battery charger + +maintainers: + - Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com> + - Markus Laine <markus.laine@fi.rohmeurope.com> + - Mikko Mutanen <mikko.mutanen@fi.rohmeurope.com> + +description: | + The ROHM BD99954 is a Battery Management LSI for 1-4 cell Lithium-Ion + secondary battery intended to be used in space-constraint equipment such + as Low profile Notebook PC, Tablets and other applications. BD99954 + provides a Dual-source Battery Charger, two port BC1.2 detection and a + Battery Monitor. + + +properties: + compatible: + const: rohm,bd99954 +# +# The battery charging profile of BD99954. +# +# Curve (1) represents charging current. +# Curve (2) represents battery voltage. +# +# The BD99954 data sheet divides charging to three phases. +# a) Trickle-charge with constant current (8). +# b) pre-charge with constant current (6) +# c) fast-charge with: +# First a constant current (5) phase (CC) +# Then constant voltage (CV) phase (after the battery voltage has reached +# target level - until charging current has dropped to termination +# level (7) +# +# V ^ ^ I +# . . +# . . +# (4)- -.- - - - - - - - - - - - - - +++++++++++++++++++++++++++. +# . / . +# . ++++++/++ - - - - - - - - - - - - -.- - (5) +# . + / + . +# . + - -- . +# . + - + . +# . +.- -: . +# . .+ +` . +# . .- + | `/ . +# . .." + .: . +# . -" + -- . +# . (2) ..." + | :- . +# . ..."" + -: . +# (3)- -.-.""- - - - -+++++++++ - - - - - - -.:- - - - - - - - - .- - (6) +# . + `:. . +# . + | -: . +# . + -: . +# . + .. . +# . (1) + | "+++- - - -.- - (7) +# -++++++++++++++- - - - - - - - - - - - - - - - - + - - - .- - (8) +# . + - +# -------------------------------------------------+++++++++--> +# | | | CC | CV | +# | --trickle-- | -pre- | ---------fast----------- | +# +# The charger uses the following battery properties +# - trickle-charge-current-microamp: +# Current used at trickle-charge phase (8 in above chart) +# minimum: 64000 +# maximum: 1024000 +# multipleOf: 64000 +# - precharge-current-microamp: +# Current used at pre-charge phase (6 in above chart) +# minimum: 64000 +# maximum: 1024000 +# multipleOf: 64000 +# - constant-charge-current-max-microamp +# Current used at fast charge constant current phase (5 in above chart) +# minimum: 64000 +# maximum: 1024000 +# multipleOf: 64000 +# - constant-charge-voltage-max-microvolt +# The constant voltage used in fast charging phase (4 in above chart) +# minimum: 2560000 +# maximum: 19200000 +# multipleOf: 16000 +# - precharge-upper-limit-microvolt +# charging mode is changed from trickle charging to pre-charging +# when battery voltage exceeds this limit voltage (3 in above chart) +# minimum: 2048000 +# maximum: 19200000 +# multipleOf: 64000 +# - re-charge-voltage-microvolt +# minimum: 2560000 +# maximum: 19200000 +# multipleOf: 16000 +# re-charging is automatically started when battry has been discharging +# to the point where the battery voltage drops below this limit +# - over-voltage-threshold-microvolt +# battery is expected to be faulty if battery voltage exceeds this limit. +# Charger will then enter to a "battery faulty" -state +# minimum: 2560000 +# maximum: 19200000 +# multipleOf: 16000 +# - charge-term-current-microamp +# minimum: 0 +# maximum: 1024000 +# multipleOf: 64000 +# a charge cycle terminates when the battery voltage is above recharge +# threshold, and the current is below this setting (7 in above chart) +# See also Documentation/devicetree/bindings/power/supply/battery.txt + + monitored-battery: + description: + phandle of battery characteristics devicetree node + + rohm,vsys-regulation-microvolt: + description: system specific lower limit for system voltage. + minimum: 2560000 + maximum: 19200000 + multipleOf: 64000 + + rohm,vbus-input-current-limit-microamp: + description: system specific VBUS input current limit (in microamps). + minimum: 32000 + maximum: 16352000 + multipleOf: 32000 + + rohm,vcc-input-current-limit-microamp: + description: system specific VCC/VACP input current limit (in microamps). + minimum: 32000 + maximum: 16352000 + multipleOf: 32000 + +required: + - compatible + +examples: + - | + i2c { + #address-cells = <1>; + #size-cells = <0>; + charger@9 { + compatible = "rohm,bd99954"; + monitored-battery = <&battery>; + reg = <0x9>; + interrupt-parent = <&gpio1>; + interrupts = <29 8>; + rohm,vsys-regulation-microvolt = <8960000>; + rohm,vbus-input-current-limit-microamp = <1472000>; + rohm,vcc-input-current-limit-microamp = <1472000>; + }; + }; |