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 /* Get the backlight power status (0: full on, 1..3: power saving
23 modes; 4: full off), see FB_BLANK_XXX */
24 int (*get_power)(struct backlight_device *);
25 /* Enable or disable power to the LCD (0: on; 4: off, see FB_BLANK_XXX) */
26 int (*set_power)(struct backlight_device *, int power);
27 /* Maximal value for brightness (read-only) */
28 int max_brightness;
29 /* Get current backlight brightness */
30 int (*get_brightness)(struct backlight_device *);
31 /* Set backlight brightness (0..max_brightness) */
32 int (*set_brightness)(struct backlight_device *, int brightness);
33 /* Check if given framebuffer device is the one bound to this backlight;
34 return 0 if not, !=0 if it is. If NULL, backlight always matches the fb. */
35 int (*check_fb)(struct fb_info *);
36};
37
38struct backlight_device {
39 /* This protects the 'props' field. If 'props' is NULL, the driver that
40 registered this device has been unloaded, and if class_get_devdata()
41 points to something in the body of that driver, it is also invalid. */
42 struct semaphore sem;
43 /* If this is NULL, the backing module is unloaded */
44 struct backlight_properties *props;
45 /* The framebuffer notifier block */
46 struct notifier_block fb_notif;
47 /* The class device structure */
48 struct class_device class_dev;
49};
50
51extern struct backlight_device *backlight_device_register(const char *name,
52 void *devdata, struct backlight_properties *bp);
53extern void backlight_device_unregister(struct backlight_device *bd);
54
55#define to_backlight_device(obj) container_of(obj, struct backlight_device, class_dev)
56
57#endif