xref: /linux/Documentation/ABI/testing/debugfs-cec-error-inj (revision 8c994eff8fcfe8ecb1f1dbebed25b4d7bb75be12)
1What:		/sys/kernel/debug/cec/*/error-inj
2Date:		March 2018
3Contact:	Hans Verkuil <hverkuil-cisco@xs4all.nl>
4Description:
5
6The CEC Framework allows for CEC error injection commands through
7debugfs. Drivers that support this will create an error-inj file
8through which the error injection commands can be given.
9
10The basic syntax is as follows:
11
12Leading spaces/tabs are ignored. If the next character is a '#' or the
13end of the line was reached, then the whole line is ignored. Otherwise
14a command is expected.
15
16It is up to the driver to decide what commands to implement. The only
17exception is that the command 'clear' without any arguments must be
18implemented and that it will remove all current error injection
19commands.
20
21This ensures that you can always do 'echo clear >error-inj' to clear any
22error injections without having to know the details of the driver-specific
23commands.
24
25Note that the output of 'error-inj' shall be valid as input to 'error-inj'.
26So this must work::
27
28	$ cat error-inj >einj.txt
29	$ cat einj.txt >error-inj
30
31Other than these basic rules described above this ABI is not considered
32stable and may change in the future.
33
34Drivers that implement this functionality must document the commands as
35part of the CEC documentation and must keep that documentation up to date
36when changes are made.
37
38The following CEC error injection implementations exist:
39
40- Documentation/userspace-api/media/cec/cec-pin-error-inj.rst
41