linux-drivers/
drivers/hwmon/pmbus

PMBus power-management chips (regulators, sequencers, hot-swap controllers)

Support for digital power-management chips that speak the PMBus protocol over SMBus/I²C, including point-of-load voltage regulators, power sequencers, hot-swap controllers, and voltage/current monitors from TI, Analog Devices, Infineon, and others. These parts sit on server, telecom, and industrial boards to deliver and monitor the many supply rails modern SoCs need.

keep conf=0.92 deploy=medium replacement=none subsystem=hwmon category=power-management
92%

recommendation

It should stay in the kernel because PMBus is a current industry standard (spec rev 1.5 in 2025) and the directory covers a wide range of digital power-management chips still being designed into servers, telecom gear, and industrial systems. Upstream activity is healthy, with bug fixes and stable backports landing as recently as March 2026, and vendors like Texas Instruments and Analog Devices continue to market PMBus parts as active or recommended for new designs.

repository signals

73 files
24,944 source lines
255 commits, 5y
+12,621 / −1,819 lines added / removed, 5y
87 authors, 5y
monthly commits · 2021-04-21 → 2026-04-21 · 255 total · active in 55/61 months
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sources

  1. lore.kernel.org

    Recent upstream/stable maintenance is active: pmbus_core.c received a March 31, 2026 fix patch (regulator mutex protection) with review and stable backport handling.

  2. lore.kernel.org

    The PMBus core also received another March 31, 2026 functional fix ('write-only' attributes), indicating ongoing bug-fix traffic rather than removal.

  3. pmbus.org

    PMBus remains a current industry standard in 2025/2026; the PMBus site lists current specification revision 1.5 and current SMBus revision 3.3.1.

  4. ti.com

    A PMBus-capable TI regulator represented in this subsystem's device class is still marketed as ACTIVE, showing new-hardware availability.

  5. analog.com

    An Analog Devices PMBus-capable sequencer supported by this directory is listed as RECOMMENDED FOR NEW DESIGNS, showing ongoing new deployments.

codex reasoning notes (technical)

`drivers/hwmon/pmbus` is an active driver subsystem, not dead glue code. lore evidence came from `lore_file_timeline` and `lore_activity` on `drivers/hwmon/pmbus/pmbus_core.c`, which showed activity through 2026-04-11 plus multiple reviewed stable backports on 2026-03-31; cited lore URLs were taken directly from those tool results. Deployment evidence came from web search results on the PMBus standards site and vendor product pages: PMBus.org shows the standard is current, TI shows TPS546D24A as ACTIVE, and Analog shows ADM1266 as RECOMMENDED FOR NEW DESIGNS. This directory covers a broad, still-current PMBus ecosystem used in servers, telecom, industrial, and power-supply management, so there is no single replacement driver and no sign here of obsolescence-driven deprecation.