drivers/auxdisplay

Auxiliary character and small graphical display panels (HD44780, KS0108, HT16K33, MAX6959)

A subsystem of small auxiliary display panels — HD44780-style character LCDs, KS0108 and CFAG12864B graphical LCDs, HT16K33 LED matrices, and MAX6959 7-segment controllers — typically wired over GPIO, parallel port, or I2C and used as front-panel readouts on routers, appliances, industrial equipment, and hobbyist projects from the 1990s through to parts still sold new today.

keep-annotate conf=0.82 last_sold=2025 deploy=low replacement=none subsystem=auxdisplay category=other
82%

recommendation

Worth keeping but documenting as a niche subsystem because it is not a single dead driver but a small collection of independent drivers for character LCDs, 7-segment controllers, and tiny graphical panels that hobbyists and industrial integrators still buy new in 2025. Upstream work continued as recently as September 2025 (new fuzz-test coverage for the charlcd parser), and supported parts like Analog's MAX6959 and HD44780-compatible LCDs from Adafruit remain in production, so there is no realistic consolidation target.

repository signals

19 files
6,749 source lines
126 commits, 5y
+2,206 / −1,182 lines added / removed, 5y
34 authors, 5y
monthly commits · 2021-04-21 → 2026-04-21 · 126 total · active in 33/61 months
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sources

  1. git.kernel.org

    The directory is a live subsystem menu for multiple auxiliary-display drivers and core helpers, not one orphaned single-device driver.

  2. lore.kernel.org

    Auxdisplay code still receives upstream work in 2025, including new KFuzzTest coverage for charlcd parsing logic.

  3. analog.com

    MAX6959 display-controller hardware supported by this directory remained in production and orderable when crawled.

  4. adafruit.com

    HD44780-compatible character LCD modules were still sold new and in stock, indicating ongoing niche new-hardware availability for a major auxdisplay use case.

codex reasoning notes (technical)

`drivers/auxdisplay` is an active mixed-hardware subsystem rather than a dead single driver, so removal is not justified. Evidence: local `exec_command` on Kconfig/file list showed multiple independent drivers plus shared cores; kernel.org Kconfig URL added by canonical recall for a stable source. `lore_activity(file=drivers/auxdisplay/charlcd.c)` returned 2025 upstream test work (lore URL obtained via MCP tool), which argues against deprecation/removal. Web search found Analog's MAX6959 page marked PRODUCTION and an Adafruit HD44780 LCD product page in stock, supporting that some supported hardware is still sold, but mainly for hobbyist/industrial niches. No natural single replacement driver covers the whole directory; annotate as niche/legacy-heavy but maintained.