1 /*-
2 * Copyright (c) 2020 The FreeBSD Foundation
3 *
4 * This software was developed by Emmanuel Vadot under sponsorship
5 * from the FreeBSD Foundation.
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 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #ifndef _LINUXKPI_LINUX_BACKLIGHT_H_
30 #define _LINUXKPI_LINUX_BACKLIGHT_H_
31
32 #include <linux/notifier.h>
33
34 struct backlight_device;
35
36 enum backlight_type {
37 BACKLIGHT_RAW = 0,
38 };
39
40 struct backlight_properties {
41 int type;
42 int max_brightness;
43 int brightness;
44 int power;
45 };
46
47 enum backlight_notification {
48 BACKLIGHT_REGISTERED,
49 BACKLIGHT_UNREGISTERED,
50 };
51
52 enum backlight_update_reason {
53 BACKLIGHT_UPDATE_HOTKEY = 0
54 };
55
56 struct backlight_ops {
57 int options;
58 #define BL_CORE_SUSPENDRESUME 1
59 int (*update_status)(struct backlight_device *);
60 int (*get_brightness)(struct backlight_device *);
61 };
62
63 struct backlight_device {
64 const struct backlight_ops *ops;
65 struct backlight_properties props;
66 void *data;
67 struct device *dev;
68 char *name;
69 };
70
71 #define bl_get_data(bd) (bd)->data
72
73 struct backlight_device *linux_backlight_device_register(const char *name,
74 struct device *dev, void *data, const struct backlight_ops *ops, struct backlight_properties *props);
75 void linux_backlight_device_unregister(struct backlight_device *bd);
76 #define backlight_device_register(name, dev, data, ops, props) \
77 linux_backlight_device_register(name, dev, data, ops, props)
78 #define backlight_device_unregister(bd) linux_backlight_device_unregister(bd)
79
80 static inline int
backlight_update_status(struct backlight_device * bd)81 backlight_update_status(struct backlight_device *bd)
82 {
83 return (bd->ops->update_status(bd));
84 }
85
86 static inline void
backlight_force_update(struct backlight_device * bd,int reason)87 backlight_force_update(struct backlight_device *bd, int reason)
88 {
89 bd->props.brightness = bd->ops->get_brightness(bd);
90 }
91
92 static inline int
backlight_get_brightness(struct backlight_device * bd)93 backlight_get_brightness(struct backlight_device *bd)
94 {
95
96 return (bd->props.brightness);
97 }
98
99 static inline int
backlight_device_set_brightness(struct backlight_device * bd,int brightness)100 backlight_device_set_brightness(struct backlight_device *bd, int brightness)
101 {
102
103 if (brightness > bd->props.max_brightness)
104 return (EINVAL);
105 bd->props.brightness = brightness;
106 return (bd->ops->update_status(bd));
107 }
108
109 static inline int
backlight_enable(struct backlight_device * bd)110 backlight_enable(struct backlight_device *bd)
111 {
112 if (bd == NULL)
113 return (0);
114 bd->props.power = 0/* FB_BLANK_UNBLANK */;
115 return (backlight_update_status(bd));
116 }
117
118 static inline int
backlight_disable(struct backlight_device * bd)119 backlight_disable(struct backlight_device *bd)
120 {
121 if (bd == NULL)
122 return (0);
123 bd->props.power = 4/* FB_BLANK_POWERDOWN */;
124 return (backlight_update_status(bd));
125 }
126
127 static inline bool
backlight_is_blank(struct backlight_device * bd)128 backlight_is_blank(struct backlight_device *bd)
129 {
130
131 return (bd->props.power != 0/* FB_BLANK_UNBLANK */);
132 }
133
134 #endif /* _LINUXKPI_LINUX_BACKLIGHT_H_ */
135