1What:		/dev/raw-kcs*
2Date:		2021-02-15
3KernelVersion:	5.13
4Contact:	openbmc@lists.ozlabs.org
5Contact:	openipmi-developer@lists.sourceforge.net
6Contact:	Andrew Jeffery <andrew@aj.id.au>
7Description:	``/dev/raw-kcs*`` exposes to userspace the data and
8		status registers of Keyboard-Controller-Style (KCS) IPMI
9		interfaces via read() and write() syscalls. Direct
10		exposure of the data and status registers enables
11		inefficient but arbitrary protocols to be implemented
12		over the device. A typical approach is to use KCS
13		devices for out-of-band signalling for bulk data
14		transfers over other interfaces between a Baseboard
15		Management Controller and its host.
16
17		+--------+--------+---------+
18		| Offset | read() | write() |
19		+--------+--------+---------+
20		|   0    |   IDR  |   ODR   |
21		+--------+--------+---------+
22		|   1    |   STR  |   STR   |
23		+--------+--------+---------+
24
25Users:		libmctp: https://github.com/openbmc/libmctp
26