diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/hwmon/lis3lv02d | 31 |
1 files changed, 24 insertions, 7 deletions
diff --git a/Documentation/hwmon/lis3lv02d b/Documentation/hwmon/lis3lv02d index 21f09025220..06534f25e64 100644 --- a/Documentation/hwmon/lis3lv02d +++ b/Documentation/hwmon/lis3lv02d @@ -20,18 +20,35 @@ sporting the feature officially called "HP Mobile Data Protection System 3D" or models (full list can be found in drivers/hwmon/hp_accel.c) 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. +/sys/devices/platform/lis3lv02d. Reported values are scaled +to mg values (1/1000th of earth gravity). 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 +rate - read reports the sampling rate of the accelerometer device in HZ. + write changes sampling rate of the accelerometer device. + Only values which are supported by HW are accepted. +selftest - performs selftest for the chip as specified by chip manufacturer. This driver also provides an absolute input class device, allowing -the laptop to act as a pinball machine-esque joystick. +the laptop to act as a pinball machine-esque joystick. Joystick device can be +calibrated. Joystick device can be in two different modes. +By default output values are scaled between -32768 .. 32767. In joystick raw +mode, joystick and sysfs position entry have the same scale. There can be +small difference due to input system fuzziness feature. +Events are also available as input event device. + +Selftest is meant only for hardware diagnostic purposes. It is not meant to be +used during normal operations. Position data is not corrupted during selftest +but interrupt behaviour is not guaranteed to work reliably. In test mode, the +sensing element is internally moved little bit. Selftest measures difference +between normal mode and test mode. Chip specifications tell the acceptance +limit for each type of the chip. Limits are provided via platform data +to allow adjustment of the limits without a change to the actual driver. +Seltest returns either "OK x y z" or "FAIL x y z" where x, y and z are +measured difference between modes. Axes are not remapped in selftest mode. +Measurement values are provided to help HW diagnostic applications to make +final decision. On HP laptops, if the led infrastructure is activated, support for a led indicating disk protection will be provided as /sys/class/leds/hp::hddprotect. |