Samsung Exynos Thermal Management Unit (TMU)
On-chip temperature monitoring and throttling hardware built into older Samsung Exynos mobile processors, including the Exynos 4210 (2011) and 4412 (2012) used in early Galaxy phones, the Exynos 5250/5260/5420/5433 found in 2012-2014 Chromebooks and tablets, and early Exynos 7 parts from 2014-2015. The TMU lets the kernel read die temperatures and trigger cooling actions to prevent overheating.
recommendation
Worth keeping but documenting its niche: the supported chips are all legacy Exynos generations from 2011-2015 that no one ships in new products, yet the code is still actively maintained upstream, with refactoring patches landing as recently as early 2026. It also remains useful for the installed base of older Exynos-based Chromebooks, ODROID boards, and development hardware, and there is no replacement driver to migrate to.
repository signals
sources
- lore.kernel.org
Upstream activity is current: in February 2026 the driver saw a non-trivial refactor patch for Exynos TMU, indicating ongoing maintenance rather than removal.
- en.wikipedia.org
The SoCs matched by this driver are legacy Exynos generations: Exynos 4210 (2011), 4412 (2012), 5250 (2012), 5260 (2014), 5420 (2013), 5433 (2014), and early Exynos 7-era parts (2014-2015).
- semiconductor.samsung.com
Samsung still sells new Exynos-branded processors in the 2020s, but this is a much newer generation than the legacy TMU blocks listed in the driver.
- semiconductor.samsung.com
Samsung had new Exynos deployments rolling out by 2025 in automotive, showing the brand continues but not that the old Exynos3250/4210/4412/5250/5260/5420/5433/7 TMU hardware remains current.
codex reasoning notes (technical)
Local shell read of exynos_tmu.c showed the compatible table covers samsung,exynos3250/4210/4412/5250/5260/5420/5433/7-tmu, i.e. older Exynos SoCs only. MCP lore_file_timeline on drivers/thermal/samsung/exynos_tmu.c showed heavy recent traffic through 2026-02-14, with refactor/fix patches and no removal signal, so this should not be deprecated now. Web search provided the Samsung Exynos 2400 and Exynos Auto V920 pages, which show Exynos as a brand is still current, but those are newer families and not evidence that this exact TMU IP is in new 2025 products. Web search also provided the Wikipedia Exynos page for launch-era dating of the supported SoCs; that supports treating the covered hardware as legacy in new-design terms. Recommendation is keep-annotate: legacy hardware with low but real installed-base relevance and active upstream maintenance, with no natural replacement driver.