Linux kernel mirror (for testing)
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linux
1/*
2 * Backlight Lowlevel Control Abstraction
3 *
4 * Copyright (C) 2003,2004 Hewlett-Packard Company
5 *
6 */
7
8#ifndef _LINUX_BACKLIGHT_H
9#define _LINUX_BACKLIGHT_H
10
11#include <linux/device.h>
12#include <linux/notifier.h>
13
14struct backlight_device;
15struct fb_info;
16
17/* This structure defines all the properties of a backlight
18 (usually attached to a LCD). */
19struct backlight_properties {
20 /* Owner module */
21 struct module *owner;
22
23 /* Notify the backlight driver some property has changed */
24 int (*update_status)(struct backlight_device *);
25 /* Return the current backlight brightness (accounting for power,
26 fb_blank etc.) */
27 int (*get_brightness)(struct backlight_device *);
28 /* Check if given framebuffer device is the one bound to this backlight;
29 return 0 if not, !=0 if it is. If NULL, backlight always matches the fb. */
30 int (*check_fb)(struct fb_info *);
31
32 /* Current User requested brightness (0 - max_brightness) */
33 int brightness;
34 /* Maximal value for brightness (read-only) */
35 int max_brightness;
36 /* Current FB Power mode (0: full on, 1..3: power saving
37 modes; 4: full off), see FB_BLANK_XXX */
38 int power;
39 /* FB Blanking active? (values as for power) */
40 int fb_blank;
41};
42
43struct backlight_device {
44 /* This protects the 'props' field. If 'props' is NULL, the driver that
45 registered this device has been unloaded, and if class_get_devdata()
46 points to something in the body of that driver, it is also invalid. */
47 struct semaphore sem;
48 /* If this is NULL, the backing module is unloaded */
49 struct backlight_properties *props;
50 /* The framebuffer notifier block */
51 struct notifier_block fb_notif;
52 /* The class device structure */
53 struct class_device class_dev;
54};
55
56extern struct backlight_device *backlight_device_register(const char *name,
57 void *devdata, struct backlight_properties *bp);
58extern void backlight_device_unregister(struct backlight_device *bd);
59
60#define to_backlight_device(obj) container_of(obj, struct backlight_device, class_dev)
61
62#endif