1.\" $OpenBSD: sensor_attach.9,v 1.3 2006/12/28 11:36:14 jmc Exp $ 2.\" 3.\" Copyright (c) 2006 Michael Knudsen <mk@openbsd.org> 4.\" Copyright (c) 2006 Constantine A. Murenin <cnst+openbsd@bugmail.mojo.ru> 5.\" All rights reserved. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 11.\" 1. Redistributions of source code must retain the above copyright 12.\" notice, this list of conditions and the following disclaimer. 13.\" 2. The name of the author may not be used to endorse or promote products 14.\" derived from this software without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, 17.\" INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY 18.\" AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 19.\" THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 20.\" EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 21.\" PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 22.\" OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 23.\" WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 24.\" OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 25.\" ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26.\" 27.Dd December 23, 2006 28.Dt SENSOR_ATTACH 9 29.Os 30.Sh NAME 31.Nm sensor_attach , 32.Nm sensor_detach , 33.Nm sensor_find , 34.Nm sensordev_install , 35.Nm sensordev_deinstall , 36.Nm sensordev_get , 37.Nm sensor_task_register , 38.Nm sensor_task_unregister 39.Nd sensors framework 40.Sh SYNOPSIS 41.Fd #include <sys/sensors.h> 42.Ft void 43.Fn "sensordev_install" "struct sensordev *sensdev" 44.Ft void 45.Fn "sensordev_deinstall" "struct sensordev *sensdev" 46.Ft struct sensordev 47.Fn "*sensordev_get" "int devnum" 48.Pp 49.Ft void 50.Fn "sensor_attach" "struct sensordev *sensdev" "struct sensor *sens" 51.Ft void 52.Fn "sensor_detach" "struct sensordev *sensdev" "struct sensor *sens" 53.Ft struct sensor 54.Fn "*sensor_find" "int devnum" "enum sensor_type stype" "int numt" 55.Pp 56.Ft int 57.Fn "sensor_task_register" "void *arg" "void (*func)(void *)" "int period" 58.Ft void 59.Fn "sensor_task_unregister" "void *arg" 60.Sh DESCRIPTION 61The 62sensors 63framework API provides a mechanism for manipulation of hardware sensors 64that are available under the 65.Va hw.sensors 66.Xr sysctl 8 67tree. 68.Pp 69.Fn sensor_attach 70adds the sensor specified by the 71.Pa sens 72argument to the sensor device specified by the 73.Pa sensdev 74argument. 75.Fn sensor_detach 76can be used to remove sensors previously added by 77.Fn sensor_attach . 78.Pp 79.Fn sensordev_install 80registers the sensor device specified by the 81.Pa sensdev 82argument so that all sensors that are attached to the device become 83accessible via the sysctl interface. 84.Fn sensordev_deinstall 85can be used to remove sensor devices previously registered by 86.Fn sensordev_install . 87.Pp 88.Fn sensordev_get 89takes ordinal number 90.Pa devnum 91specifying a sensor device and 92returns a pointer to the corresponding 93.Vt struct sensordev , 94or 95.Dv NULL 96if no such sensor device exists. 97.Pp 98.Fn sensor_find 99takes ordinal number 100.Pa devnum 101specifying a sensor device, sensor type 102.Pa stype 103and ordinal number of sensor of such type 104.Pa numt , 105and returns a pointer to the corresponding 106.Vt struct sensor , 107or 108.Dv NULL 109if no such sensor exists. 110.Fn sensor_find 111will always return 112.Dv NULL 113if the corresponding sensor devices are not registered by 114.Fn sensordev_install . 115.Pp 116Drivers are responsible for retrieving, interpreting, and normalising 117sensor values and updating the sensor struct periodically. 118If the driver needs process context, for example to sleep, it can 119register a task with the sensor framework. 120.Pp 121.Fn sensor_task_register 122is used to register a periodic task to update sensors. 123The 124.Fa func 125argument is a pointer to the function to run with an interval of 126.Fa period 127seconds. 128The 129.Fa arg 130parameter is the argument given to the 131.Fa func 132function. 133The 134.Fn sensor_task_unregister 135removes all tasks previously registered with 136.Fn sensor_task_register 137with an argument of 138.Fa arg . 139.Pp 140All the functions in the sensor framework must be called during 141.Xr autoconf 9 142or from a process context. 143Additionally, 144.Fn sensor_task_unregister 145must not be called while a function previously registered with 146.Fn sensor_task_register 147is running. 148.Sh SEE ALSO 149.Xr sysctl 8 , 150.Xr autoconf 9 151.Sh HISTORY 152The sensor framework was written by 153.An Alexander Yurchenko Aq grange@openbsd.org 154and first appeared in 155.Ox 3.4 . 156.An David Gwynne Aq dlg@openbsd.org 157later extended it for 158.Ox 3.8 . 159.An Constantine A. Murenin Aq cnst+openbsd@bugmail.mojo.ru 160extended it even further by introducing the concept of sensor devices in 161.Ox 4.1 . 162