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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.