aboutsummaryrefslogtreecommitdiff
path: root/Documentation/hwmon/lis3lv02d
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/hwmon/lis3lv02d')
-rw-r--r--Documentation/hwmon/lis3lv02d49
1 files changed, 49 insertions, 0 deletions
diff --git a/Documentation/hwmon/lis3lv02d b/Documentation/hwmon/lis3lv02d
new file mode 100644
index 00000000000..65dfb0c0fd6
--- /dev/null
+++ b/Documentation/hwmon/lis3lv02d
@@ -0,0 +1,49 @@
+Kernel driver lis3lv02d
+==================
+
+Supported chips:
+
+ * STMicroelectronics LIS3LV02DL and LIS3LV02DQ
+
+Author:
+ Yan Burman <burman.yan@gmail.com>
+ Eric Piel <eric.piel@tremplin-utc.net>
+
+
+Description
+-----------
+
+This driver provides support for the accelerometer found in various HP laptops
+sporting the feature officially called "HP Mobile Data Protection System 3D" or
+"HP 3D DriveGuard". It detect automatically laptops with this sensor. Known models
+(for now the HP 2133, nc6420, nc2510, nc8510, nc84x0, nw9440 and nx9420) will
+have their axis automatically oriented on standard way (eg: you can directly
+play neverball). The accelerometer data is readable via
+/sys/devices/platform/lis3lv02d.
+
+Sysfs attributes under /sys/devices/platform/lis3lv02d/:
+position - 3D position that the accelerometer reports. Format: "(x,y,z)"
+calibrate - read: values (x, y, z) that are used as the base for input class device operation.
+ write: forces the base to be recalibrated with the current position.
+rate - reports the sampling rate of the accelerometer device in HZ
+
+This driver also provides an absolute input class device, allowing
+the laptop to act as a pinball machine-esque joystick.
+
+Axes orientation
+----------------
+
+For better compatibility between the various laptops. The values reported by
+the accelerometer are converted into a "standard" organisation of the axes
+(aka "can play neverball out of the box"):
+ * When the laptop is horizontal the position reported is about 0 for X and Y
+and a positive value for Z
+ * If the left side is elevated, X increases (becomes positive)
+ * If the front side (where the touchpad is) is elevated, Y decreases (becomes negative)
+ * If the laptop is put upside-down, Z becomes negative
+
+If your laptop model is not recognized (cf "dmesg"), you can send an email to the
+authors to add it to the database. When reporting a new laptop, please include
+the output of "dmidecode" plus the value of /sys/devices/platform/lis3lv02d/position
+in these four cases.
+