Dallas/Maxim 1-Wire bus master adapters
Host-side adapters that let Linux talk to Dallas/Maxim 1-Wire devices, the tiny single-pin chips used for temperature sensors, ID buttons, and small EEPROMs in industrial, embedded, and hobbyist setups. Coverage includes USB dongles like the DS9490, I2C bridges like the DS2482, and bit-banged GPIO pins on embedded boards.
recommendation
Worth keeping but flagging as a niche corner of the tree. The hardware is genuinely still sold new by Analog Devices (the DS2482-100 I2C bridge and DS9490 USB adapter remain in production), the GPIO-based master is still the standard path for device-tree embedded systems, and the code is actively maintained with cleanups landing as recently as 2024-2026. The user base is small but real, mostly industrial sensing and embedded projects, so the directory should stay while being documented as legacy-skewed rather than mainstream.
repository signals
sources
- lore.kernel.org
The ds2490 master driver was still receiving upstream cleanups in April 2026, indicating ongoing maintenance rather than abandonment.
- lore.kernel.org
The w1-gpio master driver saw a 2024 patch series updating device-property handling and related cleanup, showing active upkeep for GPIO-backed 1-Wire deployments.
- analog.com
ADI lists the DS2482-100 I2C-to-1-Wire bridge as PRODUCTION with sample/buy information, so at least one core 1-Wire master chip family remains on the market.
- analog.com
ADI lists the DS9490 USB-to-1-Wire adapter as PRODUCTION, supporting continued availability of DS2490-based USB master hardware.
- kernel.org
Kernel documentation still describes w1-gpio for device-tree and GPIO-based systems, consistent with continuing embedded/industrial use rather than pure legacy status.
codex reasoning notes (technical)
Not a removal candidate: local tree metadata shows 9 C drivers in this directory and substantive touches through 2025-11-11. Lore evidence was obtained with `mcp__lore_http__.lore_activity` on `drivers/w1/masters/ds2490.c` and `drivers/w1/masters/w1-gpio.c`; those URLs show active 2024-2026 maintenance and no removal thread surfaced. Market/deployment evidence was obtained with `web.search_query`: ADI product pages show DS2482-100 and DS9490 still in production, while kernel.org docs show w1-gpio remains a supported path for modern GPIO/device-tree systems. Overall this directory mixes clearly legacy board-specific masters with still-relevant niche industrial/embedded 1-Wire bridges, so the right posture is keep but annotate as niche/legacy-skewed rather than deprecate or remove.