1.\" $NetBSD: aps.4,v 1.3 2010/06/09 13:44:24 jruoho Exp $ 2.\" $OpenBSD: aps.4,v 1.7 2007/05/31 19:19:49 jmc Exp $ 3.\" 4.\" Copyright (c) 2005 Jonathan Gray <jsg@openbsd.org> 5.\" 6.\" Permission to use, copy, modify, and distribute this software for any 7.\" purpose with or without fee is hereby granted, provided that the above 8.\" copyright notice and this permission notice appear in all copies. 9.\" 10.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 11.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 12.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 13.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 14.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 15.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 16.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17.\" 18.Dd June 9, 2010 19.Dt APS 4 20.Os 21.Sh NAME 22.Nm aps 23.Nd ThinkPad Active Protection System accelerometer 24.Sh SYNOPSIS 25.Cd "aps0 at isa? port 0x1600" 26.Sh DESCRIPTION 27The 28.Nm 29driver provides support for several sensors found in some ThinkPad laptops. 30.Pp 31The sensors currently exposed via the 32.Xr envsys 4 33interface are: 34.Bl -column "Sensor " "Units" "Typical" -offset indent 35.It Sy "Sensor" Ta Sy "Units" Ta Sy "Typical Use" 36.It Li "X_ACCEL" Ta "Integer" Ta "X Acceleration" 37.It Li "Y_ACCEL" Ta "Integer" Ta "Y Acceleration" 38.It Li "X_VAR" Ta "Integer" Ta "Weighted X Acceleration?" 39.It Li "Y_VAR" Ta "Integer" Ta "Weighted Y Acceleration?" 40.It Li "Temp1" Ta "uK" Ta "Unknown" 41.It Li "Temp2" Ta "uK" Ta "Unknown" 42.It Li "Keyboard Active" Ta "Boolean" Ta "Keyboard activity" 43.It Li "Mouse Active" Ta "Boolean" Ta "Mouse activity" 44.It Li "Lid Open" Ta "Boolean" Ta "Lid state" 45.El 46.Sh SEE ALSO 47.Xr envsys 4 , 48.Xr thinkpad 4 , 49.Xr envstat 8 50.Sh HISTORY 51The 52.Nm 53driver first appeared in 54.Ox 3.8 55and then was ported to 56.Nx 575.0. 58.Sh AUTHORS 59The 60.Nm 61driver was written by 62.An Jonathan Gray Aq jsg@openbsd.org . 63.Sh CAVEATS 64Few issues can be mentioned. 65.Bl -bullet 66.It 67The 68.Nm 69driver does not maintain state and subsequently does not take 70evasive action when it thinks the hard drive is in danger. 71Possible actions would include spinning down the hard drive 72in case excessive tremor is detected by the sensors. 73.It 74The Y axis on X40 and possibly other models seems to be inverted. 75It is unknown how to distinguish between different versions of the 76accelerometer to compensate for this in the driver at this time. 77.It 78The sensor values are refreshed every 0.5 seconds. 79Because no protection measures are taken, 80this is unnecessary and may have a negative effect on battery life. 81.It 82As IBM provides no documentation, it is not known what all the available 83sensors are used for. 84.El 85