Commit | Line | Data |
---|---|---|
1da177e4 LT |
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> | |
28ee086d | 12 | #include <linux/mutex.h> |
1da177e4 LT |
13 | #include <linux/notifier.h> |
14 | ||
28ee086d RP |
15 | /* Notes on locking: |
16 | * | |
599a52d1 RP |
17 | * backlight_device->ops_lock is an internal backlight lock protecting the |
18 | * ops pointer and no code outside the core should need to touch it. | |
28ee086d RP |
19 | * |
20 | * Access to update_status() is serialised by the update_lock mutex since | |
21 | * most drivers seem to need this and historically get it wrong. | |
22 | * | |
23 | * Most drivers don't need locking on their get_brightness() method. | |
24 | * If yours does, you need to implement it in the driver. You can use the | |
25 | * update_lock mutex if appropriate. | |
26 | * | |
27 | * Any other use of the locks below is probably wrong. | |
28 | */ | |
29 | ||
325253a6 MG |
30 | enum backlight_update_reason { |
31 | BACKLIGHT_UPDATE_HOTKEY, | |
32 | BACKLIGHT_UPDATE_SYSFS, | |
33 | }; | |
34 | ||
1da177e4 LT |
35 | struct backlight_device; |
36 | struct fb_info; | |
37 | ||
599a52d1 | 38 | struct backlight_ops { |
9905a43b | 39 | const unsigned int options; |
c835ee7f RP |
40 | |
41 | #define BL_CORE_SUSPENDRESUME (1 << 0) | |
42 | ||
6ca01765 | 43 | /* Notify the backlight driver some property has changed */ |
9905a43b | 44 | int (* const update_status)(struct backlight_device *); |
6ca01765 RP |
45 | /* Return the current backlight brightness (accounting for power, |
46 | fb_blank etc.) */ | |
9905a43b | 47 | int (* const get_brightness)(struct backlight_device *); |
1da177e4 LT |
48 | /* Check if given framebuffer device is the one bound to this backlight; |
49 | return 0 if not, !=0 if it is. If NULL, backlight always matches the fb. */ | |
9905a43b | 50 | int (* const check_fb)(struct fb_info *); |
599a52d1 | 51 | }; |
6ca01765 | 52 | |
599a52d1 RP |
53 | /* This structure defines all the properties of a backlight */ |
54 | struct backlight_properties { | |
6ca01765 RP |
55 | /* Current User requested brightness (0 - max_brightness) */ |
56 | int brightness; | |
57 | /* Maximal value for brightness (read-only) */ | |
58 | int max_brightness; | |
59 | /* Current FB Power mode (0: full on, 1..3: power saving | |
60 | modes; 4: full off), see FB_BLANK_XXX */ | |
61 | int power; | |
62 | /* FB Blanking active? (values as for power) */ | |
c835ee7f | 63 | /* Due to be removed, please use (state & BL_CORE_FBBLANK) */ |
6ca01765 | 64 | int fb_blank; |
c835ee7f RP |
65 | /* Flags used to signal drivers of state changes */ |
66 | /* Upper 4 bits are reserved for driver internal use */ | |
67 | unsigned int state; | |
68 | ||
69 | #define BL_CORE_SUSPENDED (1 << 0) /* backlight is suspended */ | |
70 | #define BL_CORE_FBBLANK (1 << 1) /* backlight is under an fb blank event */ | |
71 | #define BL_CORE_DRIVER4 (1 << 28) /* reserved for driver specific use */ | |
72 | #define BL_CORE_DRIVER3 (1 << 29) /* reserved for driver specific use */ | |
73 | #define BL_CORE_DRIVER2 (1 << 30) /* reserved for driver specific use */ | |
74 | #define BL_CORE_DRIVER1 (1 << 31) /* reserved for driver specific use */ | |
75 | ||
1da177e4 LT |
76 | }; |
77 | ||
78 | struct backlight_device { | |
599a52d1 RP |
79 | /* Backlight properties */ |
80 | struct backlight_properties props; | |
81 | ||
28ee086d RP |
82 | /* Serialise access to update_status method */ |
83 | struct mutex update_lock; | |
599a52d1 RP |
84 | |
85 | /* This protects the 'ops' field. If 'ops' is NULL, the driver that | |
86 | registered this device has been unloaded, and if class_get_devdata() | |
87 | points to something in the body of that driver, it is also invalid. */ | |
88 | struct mutex ops_lock; | |
9905a43b | 89 | const struct backlight_ops *ops; |
599a52d1 | 90 | |
1da177e4 LT |
91 | /* The framebuffer notifier block */ |
92 | struct notifier_block fb_notif; | |
655bfd7a RP |
93 | |
94 | struct device dev; | |
1da177e4 LT |
95 | }; |
96 | ||
28ee086d RP |
97 | static inline void backlight_update_status(struct backlight_device *bd) |
98 | { | |
99 | mutex_lock(&bd->update_lock); | |
599a52d1 RP |
100 | if (bd->ops && bd->ops->update_status) |
101 | bd->ops->update_status(bd); | |
28ee086d RP |
102 | mutex_unlock(&bd->update_lock); |
103 | } | |
104 | ||
1da177e4 | 105 | extern struct backlight_device *backlight_device_register(const char *name, |
9905a43b | 106 | struct device *dev, void *devdata, const struct backlight_ops *ops); |
1da177e4 | 107 | extern void backlight_device_unregister(struct backlight_device *bd); |
325253a6 MG |
108 | extern void backlight_force_update(struct backlight_device *bd, |
109 | enum backlight_update_reason reason); | |
1da177e4 | 110 | |
655bfd7a RP |
111 | #define to_backlight_device(obj) container_of(obj, struct backlight_device, dev) |
112 | ||
113 | static inline void * bl_get_data(struct backlight_device *bl_dev) | |
114 | { | |
115 | return dev_get_drvdata(&bl_dev->dev); | |
116 | } | |
1da177e4 | 117 | |
c3f8f650 RP |
118 | struct generic_bl_info { |
119 | const char *name; | |
120 | int max_intensity; | |
121 | int default_intensity; | |
122 | int limit_mask; | |
123 | void (*set_bl_intensity)(int intensity); | |
124 | void (*kick_battery)(void); | |
125 | }; | |
126 | ||
1da177e4 | 127 | #endif |