What: /dev/raw-kcs* Date: 2021-02-15 KernelVersion: 5.13 Contact: openbmc@lists.ozlabs.org Contact: openipmi-developer@lists.sourceforge.net Contact: Andrew Jeffery Description: ``/dev/raw-kcs*`` exposes to userspace the data and status registers of Keyboard-Controller-Style (KCS) IPMI interfaces via read() and write() syscalls. Direct exposure of the data and status registers enables inefficient but arbitrary protocols to be implemented over the device. A typical approach is to use KCS devices for out-of-band signalling for bulk data transfers over other interfaces between a Baseboard Management Controller and its host. +--------+--------+---------+ | Offset | read() | write() | +--------+--------+---------+ | 0 | IDR | ODR | +--------+--------+---------+ | 1 | STR | STR | +--------+--------+---------+ Users: libmctp: https://github.com/openbmc/libmctp