1.\" $NetBSD: aps.4,v 1.8 2014/03/18 18:20:39 riastradh 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 July 13, 2011 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-acceleration" Ta "integer" Ta "X-axis acceleration" 37.It Li "y-acceleration" Ta "integer" Ta "Y-axis acceleration" 38.It Li "x-variable" Ta "integer" Ta "Weighted X acceleration?" 39.It Li "y-variable" Ta "integer" Ta "Weighted Y acceleration?" 40.It Li "temperature 1" Ta "degC" Ta "Unknown temperature" 41.It Li "temperature 2" Ta "degC" Ta "Unknown temperature" 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 hpacel 4 , 49.Xr thinkpad 4 , 50.Xr envstat 8 51.Sh HISTORY 52The 53.Nm 54driver first appeared in 55.Ox 3.8 56and was then ported to 57.Nx 585.0. 59.Sh AUTHORS 60The 61.Nm 62driver was written by 63.An Jonathan Gray Aq Mt jsg@openbsd.org . 64.Sh CAVEATS 65Few issues can be mentioned. 66.Bl -bullet 67.It 68The 69.Nm 70driver does not maintain state and subsequently does not take 71evasive action when it thinks the hard drive is in danger. 72Possible actions would include spinning down the hard drive 73in case excessive tremor is detected by the sensors. 74.It 75The Y axis on X40 and possibly other models seems to be inverted. 76It is unknown how to distinguish between different versions of the 77accelerometer to compensate for this in the driver at this time. 78.It 79The sensor values are refreshed every 0.5 seconds. 80Because no protection measures are taken, 81this is unnecessary and may have a negative effect on battery life. 82.It 83As IBM provides no documentation, it is not known what all the available 84sensors are used for. 85.El 86