Silicon Labs C2 microcontroller programming interface
A small in-kernel framework for talking to Silicon Labs' C2 (Chip-2-wire) programming and debug interface, used to flash and control 8051-family 8-bit microcontrollers from a host Linux system. The only in-tree user is a board glue driver for the Eurotech DuraMAR 2150, a ruggedized mobile router deployed in fleets of buses around 2010-2011.
recommendation
A candidate for future removal because the only board it actually supports is the Eurotech DuraMAR 2150, whose major deployments date back to 2011 with no modern hardware adopting this code. Recent commits are limited to janitorial cleanups like strncpy-to-strscpy and sysfs API churn rather than real feature work, and no new in-tree users have appeared. No removal patch series has been posted yet, so deprecation rather than immediate removal is the right next step.
repository signals
sources
- lore.kernel.org
Recent upstream activity exists, but it is small-scale API churn ('Calculate bin_attribute size through group callback') rather than evidence of active feature work or broad user demand.
- lore.kernel.org
Another recent touch was a one-line hardening cleanup ('replace deprecated strncpy with strscpy'), reinforcing that current maintenance is mostly janitorial.
- silabs.com
Silicon Labs still documents C2 as a programming/debug interface for some 8-bit MCU flows, so the underlying protocol is not wholly extinct.
- eurotech.com
Eurotech's DuraMAR 2150 had real fleet deployment history (about 1,300 buses installed in 2011), which supports legacy field presence but points to an old, embedded/transport niche rather than new mainstream deployment.
codex reasoning notes (technical)
Local tree inspection via shell showed this directory is a real driver: generic C2 core plus the only in-tree client, c2port-duramar2150, for Eurotech DuraMAR 2150. lore_file_timeline on drivers/misc/c2port/core.c showed recent touches through 2025, but they are treewide API cleanups; cited lore URLs came from lore_file_timeline output. Web search found Silicon Labs still documents C2, so some niche legacy ecosystem remains, but the Linux-supported board here appears tied to old DuraMAR 2150 transport hardware with historical 2011 deployments and no clear modern replacement driver. No concrete removal series was found in the lore evidence gathered. That supports deprecate rather than remove.