linux-drivers/
drivers/gpio

GPIO controllers and expanders subsystem

General-purpose input/output pins are the simple digital signal lines exposed by SoCs, embedded boards, and I2C/SPI expander chips, used to drive LEDs, read buttons, and wire up sensors. This directory contains the Linux GPIO subsystem and per-chip drivers covering everything from Raspberry Pi headers to industrial controllers.

keep conf=0.95 deploy=high replacement=none subsystem=gpio category=bus-other
95%

recommendation

It should stay in the kernel because this is the active GPIO subsystem itself, not a legacy driver. The tree saw nearly 2,000 substantive commits from over 300 authors in the last five years, MAINTAINERS lists it as actively maintained, and GPIO-bearing hardware ships in volume today on everything from Raspberry Pi headers to industrial SoCs.

repository signals

225 files
91,711 source lines
1,977 commits, 5y
+44,494 / −23,762 lines added / removed, 5y
344 authors, 5y
monthly commits · 2021-04-21 → 2026-04-21 · 1,977 total · active in 61/61 months
2021 2022 2023 2024 2025 2026 2021-04: 11 commits · +66 −62 2021-05: 44 commits · +660 −699 2021-06: 16 commits · +91 −53 2021-07: 14 commits · +179 −139 2021-08: 19 commits · +1,359 −328 2021-09: 16 commits · +336 −48 2021-10: 15 commits · +559 −112 2021-11: 15 commits · +92 −487 2021-12: 38 commits · +2,181 −171 2022-01: 12 commits · +298 −35 2022-02: 18 commits · +196 −139 2022-03: 17 commits · +151 −95 2022-04: 29 commits · +763 −301 2022-05: 28 commits · +360 −361 2022-06: 28 commits · +183 −247 2022-07: 36 commits · +953 −1,314 2022-08: 22 commits · +486 −727 2022-09: 37 commits · +721 −903 2022-10: 36 commits · +794 −410 2022-11: 24 commits · +486 −372 2022-12: 32 commits · +795 −1,224 2023-01: 35 commits · +178 −161 2023-02: 27 commits · +1,413 −511 2023-03: 65 commits · +1,346 −389 2023-04: 11 commits · +201 −32 2023-05: 19 commits · +244 −234 2023-06: 28 commits · +437 −284 2023-07: 41 commits · +457 −250 2023-08: 51 commits · +1,092 −1,779 2023-09: 81 commits · +836 −600 2023-10: 34 commits · +335 −226 2023-11: 10 commits · +99 −72 2023-12: 31 commits · +1,867 −607 2024-01: 38 commits · +897 −700 2024-02: 41 commits · +1,189 −223 2024-03: 15 commits · +111 −112 2024-04: 24 commits · +618 −99 2024-05: 23 commits · +260 −151 2024-06: 17 commits · +457 −64 2024-07: 13 commits · +2,097 −25 2024-08: 34 commits · +517 −386 2024-09: 31 commits · +296 −406 2024-10: 67 commits · +1,788 −958 2024-11: 17 commits · +276 −64 2024-12: 23 commits · +207 −149 2025-01: 12 commits · +172 −81 2025-02: 72 commits · +1,069 −751 2025-03: 54 commits · +836 −579 2025-04: 71 commits · +1,762 −568 2025-05: 43 commits · +1,198 −517 2025-06: 62 commits · +853 −363 2025-07: 91 commits · +1,740 −946 2025-08: 56 commits · +1,352 −619 2025-09: 51 commits · +2,016 −972 2025-10: 37 commits · +823 −515 2025-11: 42 commits · +1,379 −288 2025-12: 33 commits · +814 −223 2026-01: 40 commits · +674 −297 2026-02: 13 commits · +208 −187 2026-03: 6 commits · +82 −44 2026-04: 3 commits · +4 −2

sources

  1. git.kernel.org

    The GPIO SUBSYSTEM entry lists `drivers/gpio/`, marks it `Maintained`, and names active maintainers and mailing list.

  2. kernel.org

    Kernel documentation describes GPIO as a current, broad subsystem with controller-driver APIs (`gpio_chip`), IRQ integration, DT/ACPI mappings, and active driver documentation.

  3. raspberrypi.com

    Current Raspberry Pi boards still expose a 40-pin GPIO header, showing GPIO-backed hardware remains in new products and deployments.

codex reasoning notes (technical)

Keep: this is the live GPIO subsystem, not a niche legacy driver. Prompt-provided history already shows very high recent churn (1954 substantive commits in 5y, most recent 2026-04-10, 326 authors), which is inconsistent with deprecation/removal. Local shell inspection of MAINTAINERS confirmed `drivers/gpio/` is explicitly marked Maintained; cited MAINTAINERS URL is canonical recall of the kernel.org tree page corresponding to that local file. Kernel docs URL was obtained via web search (`turn0search0`). Raspberry Pi deployment URL was obtained via web search (`turn0search4`). I attempted lore removal-discussion queries (`lore_regex`) but they timed out, and `lei` was blocked by the sandbox socket restriction; with no positive removal signal and strong active-maintenance/deployment evidence, `keep` is the defensible recommendation.