xref: /freebsd/share/man/man9/backlight.9 (revision 675aae732d3dd2ec0f12f39df3a1fbfe693a4ebd)
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23.\" $FreeBSD$
24.\"
25.Dd October 02, 2020
26.Dt BACKLIGHT 9
27.Os
28.Sh NAME
29.Nm backlight ,
30.Nm backlight_register ,
31.Nm backlight_destroy ,
32.Nm BACKLIGHT_GET_STATUS ,
33.Nm BACKLIGHT_SET_STATUS ,
34.Nd BACKLIGHT methods
35.Sh SYNOPSIS
36.Cd "device backlight"
37.In "backlight_if.h"
38.In "sys/sys/backlight.h"
39.Ft int
40.Fn BACKLIGHT_GET_STATUS "device_t bus" "struct backlight_props *props"
41.Ft int
42.Fn BACKLIGHT_SET_STATUS "device_t bus" "struct backlight_props *props"
43.Ft struct cdev *
44.Fn backlight_register "const char *name" "device_t dev"
45.Ft int
46.Fn backlight_destroy "struct cdev *cdev"
47.Sh DESCRIPTION
48The backlight driver provides a generic way for handling a panel backlight.
49.Pp
50Drivers for backlight system register themselves globally using the
51.Fn backlight_register
52function.
53They must define two methods,
54.Fn BACKLIGHT_GET_STATUS
55which is used to query the current brightness level and
56.Fn BACKLIGHT_SET_STATUS
57which is used to update it.
58.Sh INTERFACE
59.Bl -tag -width indent
60.It Fn BACKLIGHT_GET_STATUS "device_t bus" "struct backlight_props *props"
61Driver fills the current brightless level and the optional supported levels.
62.It Fn BACKLIGHT_SET_STATUS "device_t bus" "struct backlight_props *props"
63Driver update the backlight level based on the brightness member of the props
64struct.
65.El
66.Sh FILES
67.Bl -tag -width "/dev/backlight/*"
68.It Pa /dev/backlight/*
69.Sh HISTORY
70The
71.Nm backlight
72interface first appear in
73.Fx 13.0 .
74The
75.Nm backlight
76driver and manual page was written by
77.An Emmanuel Vadot Aq Mt manu@FreeBSD.org .
78