What:		/sys/module/hid_logitech/drivers/hid:logitech/<dev>/range.
Date:		July 2011
KernelVersion:	3.2
Contact:	Michal Malý <madcatxster@gmail.com>
Description:	Display minimum, maximum and current range of the steering
		wheel. Writing a value within min and max boundaries sets the
		range of the wheel.

What:		/sys/bus/hid/drivers/logitech/<dev>/alternate_modes
Date:		Feb 2015
KernelVersion:	4.1
Contact:	Michal Malý <madcatxster@gmail.com>
Description:	Displays a set of alternate modes supported by a wheel. Each
		mode is listed as follows:
		  Tag: Mode Name
		Currently active mode is marked with an asterisk. List also
		contains an abstract item "native" which always denotes the
		native mode of the wheel. Echoing the mode tag switches the
		wheel into the corresponding mode. Depending on the exact model
		of the wheel not all listed modes might always be selectable.
		If a wheel cannot be switched into the desired mode, -EINVAL
		is returned accompanied with an explanatory message in the
		kernel log.
		This entry is not created for devices that have only one mode.

		Currently supported mode switches:
		Driving Force Pro:
		  DF-EX --> DFP

		G25:
		  DF-EX --> DFP --> G25

		G27:
		  DF-EX <*> DFP <-> G25 <-> G27
		  DF-EX <*--------> G25 <-> G27
		  DF-EX <*----------------> G27

		DFGT:
		  DF-EX <*> DFP <-> DFGT
		  DF-EX <*--------> DFGT

		* hid_logitech module must be loaded with lg4ff_no_autoswitch=1
		  parameter set in order for the switch to DF-EX mode to work.

What:		/sys/bus/hid/drivers/logitech/<dev>/real_id
Date:		Feb 2015
KernelVersion:	4.1
Contact:	Michal Malý <madcatxster@gmail.com>
Description:	Displays the real model of the wheel regardless of any
		alternate mode the wheel might be switched to.
		It is a read-only value.
		This entry is not created for devices that have only one mode.