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+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 <andrew@aj.id.au>
+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