drivers/net/ethernet/qualcomm/emac

Qualcomm FSM9900 and Centriq QDF2400 on-chip Ethernet MAC

The Gigabit Ethernet controller built into a small set of Qualcomm SoCs from the mid-2010s, notably the FSM9900 small-cell platform and the Centriq 2400 (QDF2400/QDF2432) ARM server chips. It handled the wired networking interface on those boards rather than being a discrete NIC.

keep-annotate conf=0.77 last_sold=2018 deploy=low replacement=none subsystem=net category=networking-ethernet
77%

recommendation

Worth keeping but flagging as legacy because the silicon it serves is essentially out of production: Qualcomm exited the Centriq server market in 2018 and the FSM9900 small-cell generation was superseded the same year, so present-day deployments are minimal. The code is not abandoned, however — it picked up a Qualcomm-specific cleanup patch in August 2024 and a treewide conversion patch in October 2024, so maintenance burden is low and removal is not warranted yet.

repository signals

13 files
4,504 source lines
24 commits, 5y
+600 / −576 lines added / removed, 5y
17 authors, 5y
monthly commits · 2021-04-21 → 2026-04-21 · 24 total · active in 14/61 months
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sources

  1. lore.kernel.org

    The driver was still touched in netdev in October 2024 as part of a treewide platform_driver remove callback conversion, so it is not abandoned upstream.

  2. lore.kernel.org

    The driver also received a Qualcomm-EMAC-specific cleanup patch in August 2024, indicating at least occasional direct maintenance.

  3. cateee.net

    LKDDb shows CONFIG_QCOM_EMAC still present in current kernel series and maps it to ACPI IDs QCOM8070/QCOM8071 plus DT compatibles qcom,fsm9900-emac and qcom,qdf2432-emac-sgmii.

  4. android.googlesource.com

    The binding document ties this driver to Qualcomm EMAC blocks used on FSM9900 and QDF2432 platforms, confirming the supported hardware family.

  5. qualcomm.com

    Qualcomm publicly announced commercial shipment of the Centriq 2400 family in November 2017, placing one supported EMAC platform family in a short-lived 2017-era server product window.

  6. tomshardware.com

    Third-party reporting in 2018 says Qualcomm effectively exited the Centriq server business, supporting the conclusion that QDF24xx-based new deployments are now legacy rather than growing.

  7. qualcomm.com

    Qualcomm's 2018 small-cell press release centers newer FSM100xx parts, suggesting FSM9900-era small-cell silicon had already been superseded by then.

codex reasoning notes (technical)

Driver status grounded first in lore_activity on emac.c, which showed 2023-2024 netdev traffic and no evidence of an active removal wave; attempted lore_regex removal scans timed out rather than finding removal hits. Hardware-family mapping came from local source inspection plus web-opened LKDDb and the qcom-emac binding page. Sales/deployment judgment is an inference from web search results: official Qualcomm pages place Centriq/FSM9900 in 2016-2018 product generations, Tom's Hardware reports the Centriq exit in 2018, and no current-era product evidence surfaced. Result: keep the driver, but annotate it as legacy/niche hardware with low present-day deployments rather than deprecating or removing it.