linux-drivers/
drivers/power/supply

Battery chargers, fuel gauges, and AC/USB power-supply controllers

A large collection of drivers and the shared class framework that report battery state, manage charging, and expose AC/USB/DC power inputs to userspace on laptops, tablets, phones, handheld gaming devices, embedded boards, and some UPS hardware. It covers chips from vendors like Texas Instruments, Analog Devices/Maxim, X-Powers, and Microsoft Surface controllers.

keep conf=0.96 deploy=high replacement=none subsystem=power category=power-management
96%

recommendation

It should stay because this is one of the kernel's actively developed core subsystems, with hundreds of commits over the last five years and patch traffic continuing into 2025-2026 on both the class core and individual chip drivers. The hardware it supports is universal in modern portable and embedded Linux devices, and IC families it controls (such as TI BQ24190 chargers and Analog Devices MAX17201 fuel gauges) are still in active production and sold new today.

repository signals

136 files
101,536 source lines
884 commits, 5y
+35,026 / −14,911 lines added / removed, 5y
203 authors, 5y
monthly commits · 2021-04-21 → 2026-04-21 · 884 total · active in 59/61 months
2021 2022 2023 2024 2025 2026 2021-04: 3 commits · +37 −23 2021-05: 23 commits · +786 −2,444 2021-06: 9 commits · +417 −25 2021-07: 19 commits · +1,585 −575 2021-08: 20 commits · +259 −361 2021-09: 9 commits · +81 −66 2021-10: 13 commits · +152 −127 2021-11: 24 commits · +1,538 −1,297 2021-12: 5 commits · +275 −173 2022-01: 30 commits · +340 −977 2022-02: 46 commits · +2,967 −408 2022-03: 11 commits · +111 −34 2022-04: 6 commits · +104 −86 2022-05: 9 commits · +164 −88 2022-06: 9 commits · +20 −583 2022-07: 6 commits · +36 −45 2022-08: 8 commits · +1,268 −40 2022-09: 11 commits · +985 −1,327 2022-10: 17 commits · +216 −688 2022-11: 39 commits · +226 −179 2022-12: 9 commits · +87 −95 2023-01: 8 commits · +2,330 −105 2023-02: 9 commits · +1,437 −15 2023-03: 27 commits · +305 −217 2023-04: 24 commits · +193 −158 2023-05: 17 commits · +1,807 −204 2023-06: 7 commits · +25 −13 2023-07: 7 commits · +63 −35 2023-08: 7 commits · +11 −17 2023-09: 56 commits · +1,235 −249 2023-10: 11 commits · +316 −45 2023-11: 6 commits · +116 −85 2023-12: 2 commits · +414 −152 2024-01: 32 commits · +359 −461 2024-02: 9 commits · +48 −29 2024-03: 15 commits · +187 −151 2024-04: 5 commits · +22 −6 2024-05: 8 commits · +172 −110 2024-06: 12 commits · +935 −42 2024-07: 10 commits · +377 −28 2024-08: 18 commits · +1,063 −328 2024-09: 12 commits · +309 −99 2024-10: 26 commits · +769 −180 2024-11: 20 commits · +567 −251 2024-12: 43 commits · +1,759 −391 2025-01: 11 commits · +829 −92 2025-02: 21 commits · +209 −96 2025-03: 9 commits · +674 −559 2025-04: 14 commits · +1,171 −39 2025-05: 13 commits · +65 −37 2025-06: 11 commits · +271 −251 2025-07: 6 commits · +19 −23 2025-08: 14 commits · +898 −309 2025-09: 24 commits · +2,431 −234 2025-10: 12 commits · +1,673 −28 2025-11: 4 commits · +22 −21 2025-12: 20 commits · +262 −164 2026-01: 5 commits · +19 −35 2026-02: 3 commits · +10 −11 2026-03: 0 commits · +0 −0 2026-04: 0 commits · +0 −0

sources

  1. lore.kernel.org

    Recent 2026 linux-pm patch touching the power-supply core shows ongoing upstream feature work rather than retirement.

  2. lore.kernel.org

    Recent maintenance patches still touch in-tree power-supply device drivers such as surface_battery, indicating active upkeep.

  3. docs.kernel.org

    Kernel documentation describes the power_supply class as the standard userspace-facing framework for batteries, UPS, AC, and DC supplies, confirming this directory is a live subsystem rather than a legacy one-off driver.

  4. ti.com

    TI lists BQ24190 as ACTIVE and orderable, showing Linux-supported charger IC families in this directory are still sold new.

  5. analog.com

    Analog Devices lists MAX17201 as PRODUCTION with sample-and-buy availability, showing Linux-supported fuel-gauge IC families in this directory are still in current production.

codex reasoning notes (technical)

This is an active driver subsystem, not a dead leaf: phase-1 already showed 873 substantive commits in 5 years, and tool evidence matches that. `mcp__lore_http__.lore_activity` on `drivers/power/supply/power_supply_core.c` returned a 2026 linux-pm patch adding battery-technology support; a second `lore_activity` call on `surface_battery.c` showed 2024 maintenance traffic; an earlier `lore_activity` call on `axp20x_battery.c` also showed late-2025 cross-subsystem updates acked for power-supply. Removal-search attempts (`lore_regex`, `lei`) did not yield usable removal evidence here; no active deprecation/removal series was surfaced in the allotted budget. Local file inspection via shell confirmed this directory contains many real charger/fuel-gauge/battery drivers plus the class core. Deployment is still high because batteries/chargers/fuel gauges remain ubiquitous in laptops, tablets, phones, handhelds, embedded systems, and some UPS/platform niches, and vendor product pages found by `web.search_query` show supported IC families still sold in 2025. No single replacement driver exists because this directory is the current upstream subsystem for the use case.