1 files changed, 45 insertions, 0 deletions

diff --git a/Documentation/ABI/testing/sysfs-driver-hid-logitech-lg4ff b/Documentation/ABI/testing/sysfs-driver-hid-logitech-lg4ff
index 167d9032b970..b3f6a2ac5007 100644
--- a/Documentation/ABI/testing/sysfs-driver-hid-logitech-lg4ff
+++ b/Documentation/ABI/testing/sysfs-driver-hid-logitech-lg4ff
@@ -5,3 +5,48 @@ 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.