linux-drivers/
drivers/media/radio/si470x

Silicon Labs Si470x FM radio receivers

Silicon Labs Si470x family chips are small FM radio tuner ICs found in cheap USB FM radio sticks from the late 2000s and in hobbyist breakout boards like SparkFun's Si4703, which connects over I2C to boards such as the Raspberry Pi or Arduino. They let a Linux host tune and listen to broadcast FM stations and read RDS station/text data.

keep-annotate conf=0.76 last_sold=2025 deploy=low replacement=none subsystem=media category=media-other
76%

recommendation

Worth keeping but documenting its niche because the underlying chips power a small but real population of USB FM radio dongles and hobbyist breakout boards (notably SparkFun's still-stocked Si4703 board in 2025), and the code is still receiving routine upstream maintenance touch-ups as recently as September 2025. Mainstream usage is low, so a note flagging it as a legacy/hobbyist driver would help future triage without harming current users.

repository signals

6 files
2,413 source lines
14 commits, 5y
+29 / −45 lines added / removed, 5y
9 authors, 5y
monthly commits · 2021-04-21 → 2026-04-21 · 14 total · active in 12/61 months
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sources

  1. lore.kernel.org

    The driver still receives upstream touchups in 2025; recent activity is maintenance/treewide adaptation rather than abandonment or removal.

  2. sparkfun.com

    Si4703-based hardware was still sold new via retail breakout boards, indicating at least some ongoing new-hardware availability in the hobbyist/embedded market.

  3. learn.sparkfun.com

    Current Si4703 breakout/evaluation-board documentation remains published, with older revisions explicitly marked retired, supporting a legacy-but-still-available niche deployment picture.

codex reasoning notes (technical)

Kernel tree inspection via shell showed this directory is a real USB/I2C driver for Silicon Labs Si470x FM receivers, including several known USB radio products. Lore evidence came from `lore_file_timeline` on `radio-si470x-common.c`, which showed 2024-2025 activity and no removal signal in the returned recent events; cited lore URL is the newest linux-media hit from that tool. Market evidence came from web search results pointing to SparkFun's current Si4703 breakout product page and hookup guide. Conclusion: niche FM-radio hardware with low modern deployment, but not dead enough for deprecation/removal because upstream still fixes it and compatible hardware remained purchasable in 2025.