# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) %YAML 1.2 --- $id: http://devicetree.org/schemas/power/supply/battery.yaml# $schema: http://devicetree.org/meta-schemas/core.yaml# title: Battery Characteristics maintainers: - Sebastian Reichel description: | The devicetree battery node provides static battery characteristics. In smart batteries, these are typically stored in non-volatile memory on a fuel gauge chip. The battery node should be used where there is no appropriate non-volatile memory, or it is unprogrammed/incorrect. Upstream dts files should not include battery nodes, unless the battery represented cannot easily be replaced in the system by one of a different type. This prevents unpredictable, potentially harmful, behavior should a replacement that changes the battery type occur without a corresponding update to the dtb. Battery properties are named, where possible, for the corresponding elements in enum power_supply_property, defined in include/linux/power_supply.h Batteries must be referenced by chargers and/or fuel-gauges using a phandle. The phandle's property should be named "monitored-battery". properties: compatible: const: simple-battery device-chemistry: description: This describes the chemical technology of the battery. oneOf: - const: nickel-cadmium - const: nickel-metal-hydride - const: lithium-ion description: This is a blanket type for all lithium-ion batteries, including those below. If possible, a precise compatible string from below should be used, but sometimes it is unknown which specific lithium ion battery is employed and this wide compatible can be used. - const: lithium-ion-polymer - const: lithium-ion-iron-phosphate - const: lithium-ion-manganese-oxide over-voltage-threshold-microvolt: description: battery over-voltage limit re-charge-voltage-microvolt: description: limit to automatically start charging again voltage-min-design-microvolt: description: drained battery voltage voltage-max-design-microvolt: description: fully charged battery voltage energy-full-design-microwatt-hours: description: battery design energy charge-full-design-microamp-hours: description: battery design capacity trickle-charge-current-microamp: description: current for trickle-charge phase precharge-current-microamp: description: current for pre-charge phase precharge-upper-limit-microvolt: description: limit when to change to constant charging charge-term-current-microamp: description: current for charge termination phase constant-charge-current-max-microamp: description: maximum constant input current constant-charge-voltage-max-microvolt: description: maximum constant input voltage factory-internal-resistance-micro-ohms: description: battery factory internal resistance resistance-temp-table: $ref: /schemas/types.yaml#/definitions/uint32-matrix items: items: - description: the temperature in degree Celsius - description: battery internal resistance percent description: | A table providing the temperature in degree Celsius and corresponding battery internal resistance percent, which is used to look up the resistance percent according to current temperature to get an accurate batterty internal resistance in different temperatures. ocv-capacity-celsius: description: | An array containing the temperature in degree Celsius, for each of the battery capacity lookup table. operating-range-celsius: description: operating temperature range of a battery items: - description: minimum temperature at which battery can operate - description: maximum temperature at which battery can operate ambient-celsius: description: safe range of ambient temperature items: - description: alert when ambient temperature is lower than this value - description: alert when ambient temperature is higher than this value alert-celsius: description: safe range of battery temperature items: - description: alert when battery temperature is lower than this value - description: alert when battery temperature is higher than this value required: - compatible patternProperties: '^ocv-capacity-table-[0-9]+$': $ref: /schemas/types.yaml#/definitions/uint32-matrix description: | An array providing the open circuit voltage (OCV) of the battery and corresponding battery capacity percent, which is used to look up battery capacity according to current OCV value. And the open circuit voltage unit is microvolt. maxItems: 100 items: items: - description: open circuit voltage (OCV) in microvolts - description: battery capacity percent maximum: 100 additionalProperties: false examples: - | power { #address-cells = <1>; #size-cells = <0>; battery: battery { compatible = "simple-battery"; over-voltage-threshold-microvolt = <4500000>; re-charge-voltage-microvolt = <250000>; voltage-min-design-microvolt = <3200000>; voltage-max-design-microvolt = <4200000>; energy-full-design-microwatt-hours = <5290000>; charge-full-design-microamp-hours = <1430000>; precharge-current-microamp = <256000>; precharge-upper-limit-microvolt = <2500000>; charge-term-current-microamp = <128000>; constant-charge-current-max-microamp = <900000>; constant-charge-voltage-max-microvolt = <4200000>; factory-internal-resistance-micro-ohms = <250000>; ocv-capacity-celsius = <(-10) 0 10>; /* table for -10 degree Celsius */ ocv-capacity-table-0 = <4185000 100>, <4113000 95>, <4066000 90>; /* table for 0 degree Celsius */ ocv-capacity-table-1 = <4200000 100>, <4185000 95>, <4113000 90>; /* table for 10 degree Celsius */ ocv-capacity-table-2 = <4250000 100>, <4200000 95>, <4185000 90>; resistance-temp-table = <20 100>, <10 90>, <0 80>, <(-10) 60>; operating-range-celsius = <(-30) 50>; ambient-celsius = <(-5) 50>; alert-celsius = <0 40>; }; charger@11 { reg = <0x11>; monitored-battery = <&battery>; }; fuel-gauge@22 { reg = <0x22>; monitored-battery = <&battery>; }; };