Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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> |
Richard Purdie | 28ee086 | 2007-02-08 22:25:09 +0000 | [diff] [blame] | 12 | #include <linux/mutex.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 13 | #include <linux/notifier.h> |
| 14 | |
Richard Purdie | 28ee086 | 2007-02-08 22:25:09 +0000 | [diff] [blame] | 15 | /* Notes on locking: |
| 16 | * |
Richard Purdie | 599a52d | 2007-02-10 23:07:48 +0000 | [diff] [blame] | 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. |
Richard Purdie | 28ee086 | 2007-02-08 22:25:09 +0000 | [diff] [blame] | 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 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 30 | struct backlight_device; |
| 31 | struct fb_info; |
| 32 | |
Richard Purdie | 599a52d | 2007-02-10 23:07:48 +0000 | [diff] [blame] | 33 | struct backlight_ops { |
Richard Purdie | c835ee7 | 2009-01-06 21:00:19 +0000 | [diff] [blame^] | 34 | unsigned int options; |
| 35 | |
| 36 | #define BL_CORE_SUSPENDRESUME (1 << 0) |
| 37 | |
Richard Purdie | 6ca0176 | 2006-03-31 02:31:49 -0800 | [diff] [blame] | 38 | /* Notify the backlight driver some property has changed */ |
| 39 | int (*update_status)(struct backlight_device *); |
| 40 | /* Return the current backlight brightness (accounting for power, |
| 41 | fb_blank etc.) */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 42 | int (*get_brightness)(struct backlight_device *); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | /* Check if given framebuffer device is the one bound to this backlight; |
| 44 | return 0 if not, !=0 if it is. If NULL, backlight always matches the fb. */ |
| 45 | int (*check_fb)(struct fb_info *); |
Richard Purdie | 599a52d | 2007-02-10 23:07:48 +0000 | [diff] [blame] | 46 | }; |
Richard Purdie | 6ca0176 | 2006-03-31 02:31:49 -0800 | [diff] [blame] | 47 | |
Richard Purdie | 599a52d | 2007-02-10 23:07:48 +0000 | [diff] [blame] | 48 | /* This structure defines all the properties of a backlight */ |
| 49 | struct backlight_properties { |
Richard Purdie | 6ca0176 | 2006-03-31 02:31:49 -0800 | [diff] [blame] | 50 | /* Current User requested brightness (0 - max_brightness) */ |
| 51 | int brightness; |
| 52 | /* Maximal value for brightness (read-only) */ |
| 53 | int max_brightness; |
| 54 | /* Current FB Power mode (0: full on, 1..3: power saving |
| 55 | modes; 4: full off), see FB_BLANK_XXX */ |
| 56 | int power; |
| 57 | /* FB Blanking active? (values as for power) */ |
Richard Purdie | c835ee7 | 2009-01-06 21:00:19 +0000 | [diff] [blame^] | 58 | /* Due to be removed, please use (state & BL_CORE_FBBLANK) */ |
Richard Purdie | 6ca0176 | 2006-03-31 02:31:49 -0800 | [diff] [blame] | 59 | int fb_blank; |
Richard Purdie | c835ee7 | 2009-01-06 21:00:19 +0000 | [diff] [blame^] | 60 | /* Flags used to signal drivers of state changes */ |
| 61 | /* Upper 4 bits are reserved for driver internal use */ |
| 62 | unsigned int state; |
| 63 | |
| 64 | #define BL_CORE_SUSPENDED (1 << 0) /* backlight is suspended */ |
| 65 | #define BL_CORE_FBBLANK (1 << 1) /* backlight is under an fb blank event */ |
| 66 | #define BL_CORE_DRIVER4 (1 << 28) /* reserved for driver specific use */ |
| 67 | #define BL_CORE_DRIVER3 (1 << 29) /* reserved for driver specific use */ |
| 68 | #define BL_CORE_DRIVER2 (1 << 30) /* reserved for driver specific use */ |
| 69 | #define BL_CORE_DRIVER1 (1 << 31) /* reserved for driver specific use */ |
| 70 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 71 | }; |
| 72 | |
| 73 | struct backlight_device { |
Richard Purdie | 599a52d | 2007-02-10 23:07:48 +0000 | [diff] [blame] | 74 | /* Backlight properties */ |
| 75 | struct backlight_properties props; |
| 76 | |
Richard Purdie | 28ee086 | 2007-02-08 22:25:09 +0000 | [diff] [blame] | 77 | /* Serialise access to update_status method */ |
| 78 | struct mutex update_lock; |
Richard Purdie | 599a52d | 2007-02-10 23:07:48 +0000 | [diff] [blame] | 79 | |
| 80 | /* This protects the 'ops' field. If 'ops' is NULL, the driver that |
| 81 | registered this device has been unloaded, and if class_get_devdata() |
| 82 | points to something in the body of that driver, it is also invalid. */ |
| 83 | struct mutex ops_lock; |
| 84 | struct backlight_ops *ops; |
| 85 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 86 | /* The framebuffer notifier block */ |
| 87 | struct notifier_block fb_notif; |
Richard Purdie | 655bfd7 | 2007-07-09 12:17:24 +0100 | [diff] [blame] | 88 | |
| 89 | struct device dev; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 90 | }; |
| 91 | |
Richard Purdie | 28ee086 | 2007-02-08 22:25:09 +0000 | [diff] [blame] | 92 | static inline void backlight_update_status(struct backlight_device *bd) |
| 93 | { |
| 94 | mutex_lock(&bd->update_lock); |
Richard Purdie | 599a52d | 2007-02-10 23:07:48 +0000 | [diff] [blame] | 95 | if (bd->ops && bd->ops->update_status) |
| 96 | bd->ops->update_status(bd); |
Richard Purdie | 28ee086 | 2007-02-08 22:25:09 +0000 | [diff] [blame] | 97 | mutex_unlock(&bd->update_lock); |
| 98 | } |
| 99 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 100 | extern struct backlight_device *backlight_device_register(const char *name, |
Richard Purdie | 599a52d | 2007-02-10 23:07:48 +0000 | [diff] [blame] | 101 | struct device *dev, void *devdata, struct backlight_ops *ops); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 102 | extern void backlight_device_unregister(struct backlight_device *bd); |
| 103 | |
Richard Purdie | 655bfd7 | 2007-07-09 12:17:24 +0100 | [diff] [blame] | 104 | #define to_backlight_device(obj) container_of(obj, struct backlight_device, dev) |
| 105 | |
| 106 | static inline void * bl_get_data(struct backlight_device *bl_dev) |
| 107 | { |
| 108 | return dev_get_drvdata(&bl_dev->dev); |
| 109 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 110 | |
Richard Purdie | c3f8f65 | 2007-09-03 00:27:00 +0100 | [diff] [blame] | 111 | struct generic_bl_info { |
| 112 | const char *name; |
| 113 | int max_intensity; |
| 114 | int default_intensity; |
| 115 | int limit_mask; |
| 116 | void (*set_bl_intensity)(int intensity); |
| 117 | void (*kick_battery)(void); |
| 118 | }; |
| 119 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 120 | #endif |