Spreadtrum/UNISOC SC9860, SC9863A, and UMS512 SoC clock controllers
Clock tree controllers for Spreadtrum/UNISOC mobile SoCs, specifically the SC9860, SC9863A, and UMS512 chips that power budget Android phones and tablets from the late 2010s through products still sold in 2025. They gate and divide the reference clocks every other on-chip block depends on.
recommendation
It should stay in the kernel because UNISOC still actively sells these mobile SoCs in 2025 and the directory continues to receive upstream maintenance. The clocks are also a hard prerequisite for community projects like postmarketOS to bring up phones built on UMS512 and SC9863A, and there is no generic replacement since clock trees are SoC-specific.
repository signals
sources
- git.kernel.org
Upstream Linux contains dedicated Spreadtrum/UNISOC clock driver code here, including SoC-specific drivers for SC9860, SC9863A, and UMS512.
- git.kernel.org
The directory has continued upstream maintenance in recent kernel history rather than being abandoned or staged for removal.
- unisoc.com
UNISOC still markets SC9863A on its current product site, indicating the supported hardware family remained commercially relevant into 2025.
- unisoc.com
UNISOC still markets S512/UMS512 on its current product site, covering another SoC family handled by this driver directory.
- wiki.postmarketos.org
A 2025 postmarketOS device page reports UMS512-based hardware with basic/mainline support, showing at least niche present-day Linux deployments.
codex reasoning notes (technical)
Real driver directory: local shell inspection found `module_platform_driver()` in `sc9860-clk.c`, `sc9863a-clk.c`, and `ums512-clk.c`. Kernel tree/log URLs are canonical recall of stable kernel.org pages. UNISOC product URLs were obtained via web search and show the hardware family is still sold/marketed. The postmarketOS URL was obtained via web search and supports `deployments_today=low` rather than none. `replacement_driver` is null because these are SoC-specific clock controllers with no generic successor driver. Lore file-timeline on the directory prefix returned no indexed events, so I relied on the provided recent-touch stats plus kernel.org history rather than treating that as evidence of obsolescence.