xref: /openbmc/linux/Documentation/ABI/testing/debugfs-cec-error-inj (revision 54a19b4d)

What:		/sys/kernel/debug/cec/*/error-inj
Date:		March 2018
Contact:	Hans Verkuil <hverkuil-cisco@xs4all.nl>
Description:

The CEC Framework allows for CEC error injection commands through
debugfs. Drivers that support this will create an error-inj file
through which the error injection commands can be given.

The basic syntax is as follows:

Leading spaces/tabs are ignored. If the next character is a '#' or the
end of the line was reached, then the whole line is ignored. Otherwise
a command is expected.

It is up to the driver to decide what commands to implement. The only
exception is that the command 'clear' without any arguments must be
implemented and that it will remove all current error injection
commands.

This ensures that you can always do 'echo clear >error-inj' to clear any
error injections without having to know the details of the driver-specific
commands.

Note that the output of 'error-inj' shall be valid as input to 'error-inj'.
So this must work::

	$ cat error-inj >einj.txt
	$ cat einj.txt >error-inj

Other than these basic rules described above this ABI is not considered
stable and may change in the future.

Drivers that implement this functionality must document the commands as
part of the CEC documentation and must keep that documentation up to date
when changes are made.

The following CEC error injection implementations exist:

- Documentation/userspace-api/media/cec/cec-pin-error-inj.rst