| # 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 <sre@kernel.org> |
| |
| 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>; |
| }; |
| }; |
