.\"	$OpenBSD: aps.4,v 1.8 2007/12/23 22:09:19 jmc Exp $
.\"
.\" Copyright (c) 2005 Jonathan Gray <jsg@openbsd.org>
.\"
.\" Permission to use, copy, modify, and distribute this software for any
.\" purpose with or without fee is hereby granted, provided that the above
.\" copyright notice and this permission notice appear in all copies.
.\"
.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
.\"
.Dd March 18, 2010
.Dt APS 4
.Os
.Sh NAME
.Nm aps
.Nd ThinkPad Active Protection System accelerometer
.Sh SYNOPSIS
To compile this driver into the kernel,
place the following lines in your
kernel configuration file:
.Bd -ragged -offset indent
.Cd "device isa"
.Cd "device aps0 at isa? port 0x1600"
.Ed
.Pp
Alternatively, to load the driver as a
module at boot time, place the following line in
.Xr loader.conf 5 :
.Bd -literal -offset indent
aps_load="YES"
.Ed
.Sh DESCRIPTION
The
.Nm
driver provides support for several sensors found in some
.Tn ThinkPad
laptops.
.Pp
The sensors currently supported are:
.Bl -column "Sensor         " "Units  " "Typical" -offset indent
.It Sy "Sensor" Ta Sy "Units" Ta Sy "Typical Use"
.It Li "X_ACCEL" Ta "Unknown" Ta "X Acceleration"
.It Li "Y_ACCEL" Ta "Unknown" Ta "Y Acceleration"
.It Li "X_VAR" Ta "Unknown" Ta "Weighted X Acceleration?"
.It Li "Y_VAR" Ta "Unknown" Ta "Weighted Y Acceleration?"
.It Li "Temp1" Ta "uK" Ta "Unknown"
.It Li "Temp2" Ta "uK" Ta "Unknown"
.It Li "Keyboard Active" Ta "boolean" Ta "Keyboard activity"
.It Li "Mouse Active" Ta "boolean" Ta "Mouse activity"
.It Li "Lid Open" Ta "boolean" Ta "Lid state"
.El
.Pp
Sensor values are made available through the
.Dv HW_SENSORS
.Xr sysctl 3
interface,
and can be monitored with the
.Xr systat 1
.Ar sensors
display,
.Xr sensorsd 8
and
.Xr sysctl 8
.Ar hw.sensors .
For example, on a ThinkPad R51:
.Bd -literal -offset indent
%sysctl hw.sensors.aps0
hw.sensors.aps0.raw0: 488 (X_ACCEL)
hw.sensors.aps0.raw1: 481 (Y_ACCEL)
hw.sensors.aps0.raw2: 488 (X_VAR)
hw.sensors.aps0.raw3: 481 (Y_VAR)
hw.sensors.aps0.temp0: 52.00 degC
hw.sensors.aps0.temp1: 52.00 degC
hw.sensors.aps0.indicator0: Off (Keyboard Active)
hw.sensors.aps0.indicator1: Off (Mouse Active)
hw.sensors.aps0.indicator2: On (Lid Open)
.Ed
.Sh SEE ALSO
.Xr systat 1 ,
.Xr sysctl 3 ,
.Xr intro 4 ,
.Xr isa 4 ,
.Xr sensorsd 8 ,
.Xr sysctl 8
.Sh HISTORY
The
.Nm
driver first appeared in
.Ox 3.8 .
.Dx
support was added in
.Dx 2.5 .
.Sh AUTHORS
.An -nosplit
The
.Nm
driver was written by
.An Jonathan Gray Aq jsg@openbsd.org .
It was adapted to
.Dx
by
.An Constantine A. Murenin ,
University of Waterloo.
.Sh CAVEATS
The
.Nm
driver does not yet maintain state and subsequently does not take
evasive action when it thinks the hard drive is in danger.
.Pp
The Y axis on X40 and possibly other models seems to be inverted.
It is unknown how to distinguish between different versions of the
accelerometer to compensate for this in the driver at this time.
.Pp
As IBM provides no documentation, it is not known what all the available
sensors are used for.