git://bbs.cooldavid.org / net-next-2.6.git / blame
| Commit | Line | Data |
|---|---|---|
| 455fbdd3 PM |
1 | Kernel driver lis3lv02d |
| 2 | ================== | |
| 3 | ||
| 4 | Supported chips: | |
| 5 | ||
| 6 | * STMicroelectronics LIS3LV02DL and LIS3LV02DQ | |
| 7 | ||
| 8 | Author: | |
| 9 | Yan Burman <burman.yan@gmail.com> | |
| 10 | Eric Piel <eric.piel@tremplin-utc.net> | |
| 11 | ||
| 12 | ||
| 13 | Description | |
| 14 | ----------- | |
| 15 | ||
| 16 | This driver provides support for the accelerometer found in various HP laptops | |
| 17 | sporting the feature officially called "HP Mobile Data Protection System 3D" or | |
| 18 | "HP 3D DriveGuard". It detect automatically laptops with this sensor. Known models | |
| 19 | (for now the HP 2133, nc6420, nc2510, nc8510, nc84x0, nw9440 and nx9420) will | |
| 20 | have their axis automatically oriented on standard way (eg: you can directly | |
| 21 | play neverball). The accelerometer data is readable via | |
| 22 | /sys/devices/platform/lis3lv02d. | |
| 23 | ||
| 24 | Sysfs attributes under /sys/devices/platform/lis3lv02d/: | |
| 25 | position - 3D position that the accelerometer reports. Format: "(x,y,z)" | |
| 26 | calibrate - read: values (x, y, z) that are used as the base for input class device operation. | |
| 27 | write: forces the base to be recalibrated with the current position. | |
| 28 | rate - reports the sampling rate of the accelerometer device in HZ | |
| 29 | ||
| 30 | This driver also provides an absolute input class device, allowing | |
| 31 | the laptop to act as a pinball machine-esque joystick. | |
| 32 | ||
| 33 | Axes orientation | |
| 34 | ---------------- | |
| 35 | ||
| 36 | For better compatibility between the various laptops. The values reported by | |
| 37 | the accelerometer are converted into a "standard" organisation of the axes | |
| 38 | (aka "can play neverball out of the box"): | |
| 39 | * When the laptop is horizontal the position reported is about 0 for X and Y | |
| 40 | and a positive value for Z | |
| 41 | * If the left side is elevated, X increases (becomes positive) | |
| 42 | * If the front side (where the touchpad is) is elevated, Y decreases (becomes negative) | |
| 43 | * If the laptop is put upside-down, Z becomes negative | |
| 44 | ||
| 45 | If your laptop model is not recognized (cf "dmesg"), you can send an email to the | |
| 46 | authors to add it to the database. When reporting a new laptop, please include | |
| 47 | the output of "dmidecode" plus the value of /sys/devices/platform/lis3lv02d/position | |
| 48 | in these four cases. | |
| 49 |