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| 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 | |||
