Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * LCD Lowlevel Control Abstraction | |
3 | * | |
4 | * Copyright (C) 2003,2004 Hewlett-Packard Company | |
5 | * | |
6 | */ | |
7 | ||
8 | #ifndef _LINUX_LCD_H | |
9 | #define _LINUX_LCD_H | |
10 | ||
11 | #include <linux/device.h> | |
28ee086d | 12 | #include <linux/mutex.h> |
1da177e4 | 13 | #include <linux/notifier.h> |
faa312da | 14 | #include <linux/fb.h> |
1da177e4 | 15 | |
28ee086d RP |
16 | /* Notes on locking: |
17 | * | |
599a52d1 | 18 | * lcd_device->ops_lock is an internal backlight lock protecting the ops |
28ee086d RP |
19 | * field and no code outside the core should need to touch it. |
20 | * | |
21 | * Access to set_power() is serialised by the update_lock mutex since | |
22 | * most drivers seem to need this and historically get it wrong. | |
23 | * | |
24 | * Most drivers don't need locking on their get_power() method. | |
25 | * If yours does, you need to implement it in the driver. You can use the | |
26 | * update_lock mutex if appropriate. | |
27 | * | |
28 | * Any other use of the locks below is probably wrong. | |
29 | */ | |
30 | ||
1da177e4 LT |
31 | struct lcd_device; |
32 | struct fb_info; | |
33 | ||
1da177e4 | 34 | struct lcd_properties { |
599a52d1 RP |
35 | /* The maximum value for contrast (read-only) */ |
36 | int max_contrast; | |
37 | }; | |
38 | ||
39 | struct lcd_ops { | |
1da177e4 LT |
40 | /* Get the LCD panel power status (0: full on, 1..3: controller |
41 | power on, flat panel power off, 4: full off), see FB_BLANK_XXX */ | |
42 | int (*get_power)(struct lcd_device *); | |
43 | /* Enable or disable power to the LCD (0: on; 4: off, see FB_BLANK_XXX) */ | |
44 | int (*set_power)(struct lcd_device *, int power); | |
1da177e4 LT |
45 | /* Get the current contrast setting (0-max_contrast) */ |
46 | int (*get_contrast)(struct lcd_device *); | |
47 | /* Set LCD panel contrast */ | |
48 | int (*set_contrast)(struct lcd_device *, int contrast); | |
faa312da EM |
49 | /* Set LCD panel mode (resolutions ...) */ |
50 | int (*set_mode)(struct lcd_device *, struct fb_videomode *); | |
1da177e4 LT |
51 | /* Check if given framebuffer device is the one LCD is bound to; |
52 | return 0 if not, !=0 if it is. If NULL, lcd always matches the fb. */ | |
0c531360 | 53 | int (*check_fb)(struct lcd_device *, struct fb_info *); |
1da177e4 LT |
54 | }; |
55 | ||
56 | struct lcd_device { | |
599a52d1 RP |
57 | struct lcd_properties props; |
58 | /* This protects the 'ops' field. If 'ops' is NULL, the driver that | |
1da177e4 LT |
59 | registered this device has been unloaded, and if class_get_devdata() |
60 | points to something in the body of that driver, it is also invalid. */ | |
599a52d1 | 61 | struct mutex ops_lock; |
1da177e4 | 62 | /* If this is NULL, the backing module is unloaded */ |
599a52d1 | 63 | struct lcd_ops *ops; |
28ee086d RP |
64 | /* Serialise access to set_power method */ |
65 | struct mutex update_lock; | |
1da177e4 LT |
66 | /* The framebuffer notifier block */ |
67 | struct notifier_block fb_notif; | |
655bfd7a RP |
68 | |
69 | struct device dev; | |
1da177e4 LT |
70 | }; |
71 | ||
28ee086d RP |
72 | static inline void lcd_set_power(struct lcd_device *ld, int power) |
73 | { | |
74 | mutex_lock(&ld->update_lock); | |
599a52d1 RP |
75 | if (ld->ops && ld->ops->set_power) |
76 | ld->ops->set_power(ld, power); | |
28ee086d RP |
77 | mutex_unlock(&ld->update_lock); |
78 | } | |
79 | ||
1da177e4 | 80 | extern struct lcd_device *lcd_device_register(const char *name, |
655bfd7a | 81 | struct device *parent, void *devdata, struct lcd_ops *ops); |
1da177e4 LT |
82 | extern void lcd_device_unregister(struct lcd_device *ld); |
83 | ||
655bfd7a RP |
84 | #define to_lcd_device(obj) container_of(obj, struct lcd_device, dev) |
85 | ||
86 | static inline void * lcd_get_data(struct lcd_device *ld_dev) | |
87 | { | |
88 | return dev_get_drvdata(&ld_dev->dev); | |
89 | } | |
90 | ||
1da177e4 LT |
91 | |
92 | #endif |