HID: ntrig: document sysfs interface

Add sysfs documentation for N-Trig touchscreens under Documentation/ABI.
Descriptions have been collected from code comments.

Signed-off-by: Aishwarya Pant <aishpant@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

diff --git a/Documentation/ABI/testing/sysfs-driver-hid-ntrig b/Documentation/ABI/testing/sysfs-driver-hid-ntrig
new file mode 100644 (file)
index 0000000..e574a56
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-driver-hid-ntrig
@@ -0,0 +1,70 @@
+What:          /sys/bus/hid/drivers/ntrig/<dev>/activate_slack
+Date:          May, 2010
+KernelVersion: 2.6.35
+Contact:       linux-input@vger.kernel.org
+Description:
+               (RW) Number of contact frames ignored before acknowledging the
+               start of activity (activating touch).
+
+
+What:          /sys/bus/hid/drivers/ntrig/<dev>/decativate_slack
+Date:          May, 2010
+KernelVersion: 2.6.35
+Contact:       linux-input@vger.kernel.org
+Description:
+               (RW) Number of empty (no contact) frames ignored before
+               acknowledging the end of activity (deactivating touch).
+
+               When the last finger is removed from the device, it sends a
+               number of empty frames. By holding off on deactivation for a few
+               frames false erroneous disconnects can be tolerated, where the
+               sensor may mistakenly not detect a finger that is still present.
+
+
+What:          /sys/bus/hid/drivers/ntrig/<dev>/activation_width
+What:          /sys/bus/hid/drivers/ntrig/<dev>/activation_height
+Date:          May, 2010
+KernelVersion: 2.6.35
+Contact:       linux-input@vger.kernel.org
+Description:
+               Threholds to override activation slack.
+
+               activation_width:       (RW) Width threshold to immediately
+                                       start processing touch events.
+
+               activation_height:      (RW) Height threshold to immediately
+                                       start processing touch events.
+
+
+What:          /sys/bus/hid/drivers/ntrig/<dev>/min_width
+What:          /sys/bus/hid/drivers/ntrig/<dev>/min_height
+Date:          May, 2010
+KernelVersion: 2.6.35
+Contact:       linux-input@vger.kernel.org
+Description:
+               Minimum size contact accepted.
+
+               min_width:      (RW) Minimum touch contact width to decide
+                               activation and activity.
+
+               min_height:     (RW) Minimum touch contact height to decide
+                               activation and activity.
+
+
+What:          /sys/bus/hid/drivers/ntrig/<dev>/sensor_physical_width
+What:          /sys/bus/hid/drivers/ntrig/<dev>/sensor_physical_height
+Date:          May, 2010
+KernelVersion: 2.6.35
+Contact:       linux-input@vger.kernel.org
+Description:
+               (RO) These are internal ranges not used for normal events but
+               useful for tuning.
+
+
+What:          /sys/bus/hid/drivers/ntrig/<dev>/sensor_logical_width
+What:          /sys/bus/hid/drivers/ntrig/<dev>/sensor_logical_height
+Date:          May, 2010
+KernelVersion: 2.6.35
+Contact:       linux-input@vger.kernel.org
+Description:
+               (RO) The range for positions reported during activity.