xref: /dragonfly/share/man/man9/sensor_attach.9 (revision c3762235)
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3.\" Copyright (c) 2006 Michael Knudsen <mk@openbsd.org>
4.\" Copyright (c) 2006 Constantine A. Murenin <cnst+openbsd@bugmail.mojo.ru>
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27.Dd August 19, 2007
28.Dt SENSOR_ATTACH 9
29.Os
30.Sh NAME
31.Nm sensor_attach ,
32.Nm sensor_detach ,
33.Nm sensordev_install ,
34.Nm sensordev_deinstall ,
35.Nm sensor_task_register ,
36.Nm sensor_task_unregister
37.Nd sensors framework
38.Sh SYNOPSIS
39.In sys/time.h
40.In sys/sensors.h
41.Ft void
42.Fn "sensordev_install" "struct ksensordev *sensdev"
43.Ft void
44.Fn "sensordev_deinstall" "struct ksensordev *sensdev"
45.Ft void
46.Fn "sensor_attach" "struct ksensordev *sensdev" "struct ksensor *sens"
47.Ft void
48.Fn "sensor_detach" "struct ksensordev *sensdev" "struct ksensor *sens"
49.Ft int
50.Fn "sensor_task_register" "void *arg" "void (*func)(void *)" "int period"
51.Ft void
52.Fn "sensor_task_unregister" "void *arg"
53.Sh DESCRIPTION
54The
55sensors
56framework API provides a mechanism for manipulation of hardware sensors
57that are available under the
58.Va hw.sensors
59.Xr sysctl 8
60tree.
61.Pp
62The
63.Fn sensor_attach
64function adds the sensor specified by the
65.Fa sens
66argument to the sensor device specified by the
67.Fa sensdev
68argument.
69The
70.Fn sensor_detach
71function can be used to remove sensors previously added by
72.Fn sensor_attach .
73.Pp
74The
75.Fn sensordev_install
76function registers the sensor device specified by the
77.Fa sensdev
78argument so that all sensors that are attached to the device become
79accessible via the sysctl interface.
80The
81.Fn sensordev_deinstall
82function can be used to remove sensor devices previously registered by
83.Fn sensordev_install .
84.Pp
85Drivers are responsible for retrieving, interpreting and normalising
86sensor values and updating the sensor struct periodically.
87If the driver needs process context, for example to sleep, it can
88register a task with the sensor framework.
89.Pp
90The
91.Fn sensor_task_register
92function is used to register a periodic task to update sensors.
93The
94.Fa func
95argument is a pointer to the function to run with an interval of
96.Fa period
97seconds.
98The
99.Fa arg
100parameter is the argument given to the
101.Fa func
102function.
103The
104.Fn sensor_task_unregister
105function removes all tasks previously registered with
106.Fn sensor_task_register
107with an argument of
108.Fa arg .
109.Sh COMPATIBILITY
110.Ss sensor_task
111The
112.Fn sensor_task_register
113and
114.Fn sensor_task_unregister
115functions that are included in
116.Ox 4.2
117and later
118are not compatible with
119.Dx .
120.Dx
121includes an implementation that is similar and compatible
122with an earlier version of
123these
124.Fn sensor_task
125functions that was available from
126.Ox 3.9
127until
128.Ox 4.1 .
129.Pp
130Drivers that only call
131.Fn sensor_task_register
132and do not check its return value are not affected by this
133.Fn sensor_task
134compatibility notice.
135.Sh SEE ALSO
136.Xr systat 1 ,
137.Xr sysctl 3 ,
138.Xr sensorsd 8 ,
139.Xr sysctl 8
140.Sh HISTORY
141The sensor framework was written by
142.An Alexander Yurchenko Aq Mt grange@openbsd.org
143and first appeared in
144.Ox 3.4 .
145.An David Gwynne Aq Mt dlg@openbsd.org
146later extended it for
147.Ox 3.8 .
148.An Constantine A. Murenin Aq Mt cnst+openbsd@bugmail.mojo.ru
149extended it even further by introducing the concept of sensor devices in
150.Ox 4.1 .
151.Pp
152The framework was ported to
153.Fx
154by
155.An Constantine A. Murenin
156as a Google Summer of Code 2007 project.
157