The Power-Supply Subsystem
summary
Overview of the Linux power-supply subsystem: it exposes batteries and chargers under sysfs power_supply with properties in microvolts/microamps, supports device-tree instantiation via a template driver and probe path that registers with power_supply_register, and reads/writes via regmap/I2C handlers. A patch adds custom attribute support (4.21) to avoid races. Work in progress adds device-tree curves to convert open‑circuit voltage to percent capacity. Known gaps: no clean way to represent one battery driven by multiple fuel gauges, and no unified kernel charging manager for embedded devices.
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chapters (13)
- 0:00Intro
- 0:23The power supply
- 1:21Userspace Interface
- 4:03Power Supply Types
- 4:31Smart Batteries
- 5:27Driver Construct
- 5:59Device Tree
- 6:59Probe Function 2/2
- 11:34Power Supply property sette 1/2
- 12:43Power Supply - DONE
- 14:17power supply documentation
- 14:57Power Supply - Supply Chain 1/2
- 21:38Shortcoming Charger Manager
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