Chemical and environmental gas/particulate sensors (VOC, CO2, PM, pH)
Drivers for modern chemical and environmental sensors: CO2 (Sensirion SCD30/SCD4x, Senseair Sunrise), VOC and air-quality (Bosch BME680, Sensirion SGP30/SGP40), particulate matter (Sensirion SPS30), and water-quality probes for pH, conductivity, and dissolved oxygen. These chips are common in indoor air-quality monitors, HVAC gear, smart-home devices, and industrial monitoring.
recommendation
It should stay because this directory hosts an active, growing collection of drivers for chemical and air-quality sensors that vendors like Sensirion, Bosch, and Senseair still sell new in 2025 for HVAC, indoor air quality, and industrial monitoring. Recent linux-iio patch activity in 2026 touching files such as sunrise_co2.c and scd4x.c shows ongoing maintenance rather than any move toward retirement.
repository signals
sources
- git.kernel.org
The directory is a live collection of many current chemical/environmental sensor drivers, including Bosch BME680, Sensirion SCD30/SCD4x/SGP30/SGP40/SPS30, Senseair Sunrise CO2, and others; it is not a single legacy chipset.
- lore.kernel.org
A linux-iio patch in March 2026 still touched files in this directory (including sunrise_co2.c), showing ongoing upstream maintenance rather than retirement.
- lore.kernel.org
A linux-iio treewide API update in February 2026 touched drivers in this directory (including scd4x.c), indicating the subtree remains integrated and maintained.
- sensirion.com
Sensirion still markets the SPS30 particulate-matter sensor with a 'Buy now' path and current product collateral, supporting that covered hardware was still sold new in/after 2025.
- developer.sensirion.com
Sensirion still promotes the SCD4x CO2 family as a current product line with evaluation hardware, supporting ongoing new deployments.
codex reasoning notes (technical)
Not a removal candidate. Local Kconfig inspection via `exec_command` showed a broad, modern sensor class rather than one obsolete device; cited the canonical git.kernel.org Kconfig URL by canonical recall. `lore_activity` on `sunrise_co2.c` and `scd4x.c` returned 2026 linux-iio patches, and none indicated deprecation/removal. `web.search_query` found current Sensirion product pages for SPS30 and SCD4x, showing hardware covered by this directory is still sold for HVAC/IAQ/industrial monitoring. No single upstream replacement driver exists because this directory aggregates many distinct sensor vendors/protocols.