PPS (Pulse-Per-Second) signal generators, including Intel Timed I/O
Hardware that emits precise once-per-second timing pulses used to synchronize external equipment to a system clock. The directory holds a small test/dummy generator and a driver for Intel's Timed I/O block, which is built into Intel CPUs from 2019 onward (Elkhart Lake and newer) and exposes ACPI-enumerated timing outputs for industrial automation, telecom, and scientific timing setups.
recommendation
Worth keeping but documenting its niche role: Intel added a brand-new Timed I/O generator driver here in February 2025 and follow-up fixes have continued, so the code is actively maintained and the underlying hardware ships on current Intel silicon. The only recent removal was a January 2026 cleanup of the long-broken parallel-port sub-driver, which does not threaten the rest. Real-world deployments are small because making use of PPS output usually requires specialized external timing gear, so a brief note explaining who actually needs this would help packagers and admins.
repository signals
sources
- lore.kernel.org
The directory is actively developed: Intel's Timed I/O PPS generator driver was added in February 2025 as new functionality, not legacy-only maintenance.
- patch.msgid.link
The only recent removal activity was deletion of the long-broken pps_gen_parport subdriver in January 2026; this is cleanup inside the directory, not a proposal to remove the remaining PPS generator support.
- kernel.org
Kernel documentation says Intel Timed I/O is present on 2019 and newer Intel CPUs and is used to generate precise PPS signals for synchronizing external devices.
- cateee.net
LKDDb shows CONFIG_PPS_GENERATOR_TIO in current kernel series and lists active ACPI IDs INTC1021-INTC1024 and module pps_gen_tio.
codex reasoning notes (technical)
Local shell inspection shows this is real driver code plus core infrastructure, with a dummy test generator and an Intel TIO platform driver. Local git history (shell) shows substantive activity in 2024-2026, including a new Intel TIO driver and follow-up fixes; the 2026 removal was only for the broken parport subdriver. URLs were obtained from `git show` commit Link fields (lore.kernel.org, patch.msgid.link) and one web search result each for kernel.org docs and LKDDb. Recommendation is keep-annotate because upstream attention is current, hardware is still shipping via modern Intel CPUs, but actual deployments are niche due to the need for specialized external timing hardware.