Silicon Labs Si4713 FM radio transmitter chips
A small Silicon Labs FM broadcast transmitter chip with built-in RDS support, connected over I2C or USB. It showed up in low-power FM transmitter gadgets and hobbyist breakout boards (notably Adafruit's now-discontinued module) during the 2010s, letting devices stream audio to a nearby car or home FM radio.
recommendation
Worth keeping but flagging as legacy hardware. The Si4713 chip itself is marked obsolete at Skyworks and the popular Adafruit breakout is no longer stocked, so almost no one is buying new boards in 2025. However, the driver is still receiving routine media-subsystem maintenance (a September 2025 patch series touched it) and existing hobbyist hardware in the field has no in-tree alternative, so removing it would needlessly break working setups.
repository signals
sources
- lore.kernel.org
The driver still receives upstream treewide/media API maintenance in 2025; recent lore history does not show a removal/deprecation series for this path.
- adafruit.com
A mainstream SI4713 breakout that once represented hobbyist/new deployments is marked 'No longer stocked'.
- digikey.com
The underlying SI4713 chip is listed as 'Obsolete' and no longer manufactured.
codex reasoning notes (technical)
Real driver directory: local shell read of Kconfig/si4713.c shows Silicon Labs SI4713 FM transmitter support over I2C/USB/platform. lore_file_timeline on radio-platform-si4713.c found 2021-2025 activity, with a 2025 linux-media patch URL above; this looks like ongoing build/API upkeep rather than an abandoned or removal-targeted driver. Web search found Adafruit's SI4713 breakout page marked no longer stocked and DigiKey's SI4713 part page marked obsolete, so new-hardware demand appears effectively gone. With low but nonzero legacy/hobbyist use and no natural in-tree replacement for the same transmitter chip, keep the driver but annotate it as legacy/obsolete hardware rather than deprecating for removal.