.\" $NetBSD: hpacel.4,v 1.4 2011/09/07 08:54:41 jruoho Exp $
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.\" Copyright (c) 2011 Jukka Ruohonen <jruohonen@iki.fi>
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.Dd September 7, 2011
.Dt HPACEL 4
.Os
.Sh NAME
.Nm hpacel
.Nd HP 3D DriveGuard accelerometer
.Sh SYNOPSIS
.Cd "hpacel* at acpi?"
.Sh DESCRIPTION
The
.Nm
device driver supports accelerometers that are
commonly available in Hewlett-Packard laptops.
The supported chip is
.Dv LIS3LV02DL
from STMicroelectronics, although other chips from the same family, such as
.Dv LIS3LV02DQ ,
may also work, provided that the vendor has implemented suitable
.Dv ACPI
access methods.
.Pp
The
.Nm
driver reports the acceleration readings of the X-, Y-, and Z-axis
via the
.Xr envsys 4
.Tn API
and the
.Xr envstat 8
command.
.Sh SEE ALSO
.Xr acpi 4 ,
.Xr aps 4 ,
.Xr hpqlb 4 ,
.Xr wmihp 4
.Rs
.%A STMicroelectronics
.%T "LIS3LV02DL: 3-Axis - \*(Pm\* 2g/\*(Pm\* 6g digital output \
low voltage linear accelerometer. AN2381 Application Note"
.%N Revision 1
.%D June, 2006
.%U http://www.st.com/stonline/products/literature/anp/12441.pdf
.Re
.Sh HISTORY
The
.Nm
device driver appeared in
.Nx 6.0 .
.Sh AUTHORS
.An Jukka Ruohonen
.Aq jruohonen@iki.fi
.Sh BUGS
The used accelerometer chip is capable of generating wake-up,
direction detection, and free-fall interrupts.
In the ideal situation these could be used to evoke possible emergency action.
However, the
.Nm
driver only reports the readings from the accelerometer via
.Xr sysmon_envsys 9 .