1 /* SPDX-License-Identifier: GPL-2.0 */ 1 /* SPDX-License-Identifier: GPL-2.0 */
2 /* 2 /*
3 * LCD Lowlevel Control Abstraction 3 * LCD Lowlevel Control Abstraction
4 * 4 *
5 * Copyright (C) 2003,2004 Hewlett-Packard Com 5 * Copyright (C) 2003,2004 Hewlett-Packard Company
6 * 6 *
7 */ 7 */
8 8
9 #ifndef _LINUX_LCD_H 9 #ifndef _LINUX_LCD_H
10 #define _LINUX_LCD_H 10 #define _LINUX_LCD_H
11 11
12 #include <linux/device.h> 12 #include <linux/device.h>
13 #include <linux/mutex.h> 13 #include <linux/mutex.h>
14 #include <linux/notifier.h> 14 #include <linux/notifier.h>
15 #include <linux/fb.h> 15 #include <linux/fb.h>
16 16
17 /* Notes on locking: 17 /* Notes on locking:
18 * 18 *
19 * lcd_device->ops_lock is an internal backlig 19 * lcd_device->ops_lock is an internal backlight lock protecting the ops
20 * field and no code outside the core should n 20 * field and no code outside the core should need to touch it.
21 * 21 *
22 * Access to set_power() is serialised by the 22 * Access to set_power() is serialised by the update_lock mutex since
23 * most drivers seem to need this and historic 23 * most drivers seem to need this and historically get it wrong.
24 * 24 *
25 * Most drivers don't need locking on their ge 25 * Most drivers don't need locking on their get_power() method.
26 * If yours does, you need to implement it in 26 * If yours does, you need to implement it in the driver. You can use the
27 * update_lock mutex if appropriate. 27 * update_lock mutex if appropriate.
28 * 28 *
29 * Any other use of the locks below is probabl 29 * Any other use of the locks below is probably wrong.
30 */ 30 */
31 31
32 struct lcd_device; 32 struct lcd_device;
33 struct fb_info; 33 struct fb_info;
34 34
35 struct lcd_properties { 35 struct lcd_properties {
36 /* The maximum value for contrast (rea 36 /* The maximum value for contrast (read-only) */
37 int max_contrast; 37 int max_contrast;
38 }; 38 };
39 39
40 struct lcd_ops { 40 struct lcd_ops {
41 /* Get the LCD panel power status (0: 41 /* Get the LCD panel power status (0: full on, 1..3: controller
42 power on, flat panel power off, 4: 42 power on, flat panel power off, 4: full off), see FB_BLANK_XXX */
43 int (*get_power)(struct lcd_device *); 43 int (*get_power)(struct lcd_device *);
44 /* Enable or disable power to the LCD 44 /* Enable or disable power to the LCD (0: on; 4: off, see FB_BLANK_XXX) */
45 int (*set_power)(struct lcd_device *, 45 int (*set_power)(struct lcd_device *, int power);
46 /* Get the current contrast setting (0 46 /* Get the current contrast setting (0-max_contrast) */
47 int (*get_contrast)(struct lcd_device 47 int (*get_contrast)(struct lcd_device *);
48 /* Set LCD panel contrast */ 48 /* Set LCD panel contrast */
49 int (*set_contrast)(struct lcd_device 49 int (*set_contrast)(struct lcd_device *, int contrast);
50 /* Set LCD panel mode (resolutions ... 50 /* Set LCD panel mode (resolutions ...) */
51 int (*set_mode)(struct lcd_device *, s 51 int (*set_mode)(struct lcd_device *, struct fb_videomode *);
52 /* Check if given framebuffer device i 52 /* Check if given framebuffer device is the one LCD is bound to;
53 return 0 if not, !=0 if it is. If N 53 return 0 if not, !=0 if it is. If NULL, lcd always matches the fb. */
54 int (*check_fb)(struct lcd_device *, s 54 int (*check_fb)(struct lcd_device *, struct fb_info *);
55 }; 55 };
56 56
57 struct lcd_device { 57 struct lcd_device {
58 struct lcd_properties props; 58 struct lcd_properties props;
59 /* This protects the 'ops' field. If ' 59 /* This protects the 'ops' field. If 'ops' is NULL, the driver that
60 registered this device has been unl 60 registered this device has been unloaded, and if class_get_devdata()
61 points to something in the body of 61 points to something in the body of that driver, it is also invalid. */
62 struct mutex ops_lock; 62 struct mutex ops_lock;
63 /* If this is NULL, the backing module 63 /* If this is NULL, the backing module is unloaded */
64 const struct lcd_ops *ops; !! 64 struct lcd_ops *ops;
65 /* Serialise access to set_power metho 65 /* Serialise access to set_power method */
66 struct mutex update_lock; 66 struct mutex update_lock;
67 /* The framebuffer notifier block */ 67 /* The framebuffer notifier block */
68 struct notifier_block fb_notif; 68 struct notifier_block fb_notif;
69 69
70 struct device dev; 70 struct device dev;
71 }; 71 };
72 72
73 struct lcd_platform_data { 73 struct lcd_platform_data {
74 /* reset lcd panel device. */ 74 /* reset lcd panel device. */
75 int (*reset)(struct lcd_device *ld); 75 int (*reset)(struct lcd_device *ld);
76 /* on or off to lcd panel. if 'enable' 76 /* on or off to lcd panel. if 'enable' is 0 then
77 lcd power off and 1, lcd power on. 77 lcd power off and 1, lcd power on. */
78 int (*power_on)(struct lcd_device *ld, 78 int (*power_on)(struct lcd_device *ld, int enable);
79 79
80 /* it indicates whether lcd panel was 80 /* it indicates whether lcd panel was enabled
81 from bootloader or not. */ 81 from bootloader or not. */
82 int lcd_enabled; 82 int lcd_enabled;
83 /* it means delay for stable time when 83 /* it means delay for stable time when it becomes low to high
84 or high to low that is dependent on 84 or high to low that is dependent on whether reset gpio is
85 low active or high active. */ 85 low active or high active. */
86 unsigned int reset_delay; 86 unsigned int reset_delay;
87 /* stable time needing to become lcd p 87 /* stable time needing to become lcd power on. */
88 unsigned int power_on_delay; 88 unsigned int power_on_delay;
89 /* stable time needing to become lcd p 89 /* stable time needing to become lcd power off. */
90 unsigned int power_off_delay; 90 unsigned int power_off_delay;
91 91
92 /* it could be used for any purpose. * 92 /* it could be used for any purpose. */
93 void *pdata; 93 void *pdata;
94 }; 94 };
95 95
96 static inline void lcd_set_power(struct lcd_de 96 static inline void lcd_set_power(struct lcd_device *ld, int power)
97 { 97 {
98 mutex_lock(&ld->update_lock); 98 mutex_lock(&ld->update_lock);
99 if (ld->ops && ld->ops->set_power) 99 if (ld->ops && ld->ops->set_power)
100 ld->ops->set_power(ld, power); 100 ld->ops->set_power(ld, power);
101 mutex_unlock(&ld->update_lock); 101 mutex_unlock(&ld->update_lock);
102 } 102 }
103 103
104 extern struct lcd_device *lcd_device_register( 104 extern struct lcd_device *lcd_device_register(const char *name,
105 struct device *parent, void *devdata, !! 105 struct device *parent, void *devdata, struct lcd_ops *ops);
106 extern struct lcd_device *devm_lcd_device_regi 106 extern struct lcd_device *devm_lcd_device_register(struct device *dev,
107 const char *name, struct device *paren 107 const char *name, struct device *parent,
108 void *devdata, const struct lcd_ops *o !! 108 void *devdata, struct lcd_ops *ops);
109 extern void lcd_device_unregister(struct lcd_d 109 extern void lcd_device_unregister(struct lcd_device *ld);
110 extern void devm_lcd_device_unregister(struct 110 extern void devm_lcd_device_unregister(struct device *dev,
111 struct lcd_device *ld); 111 struct lcd_device *ld);
112 112
113 #define to_lcd_device(obj) container_of(obj, s 113 #define to_lcd_device(obj) container_of(obj, struct lcd_device, dev)
114 114
115 static inline void * lcd_get_data(struct lcd_d 115 static inline void * lcd_get_data(struct lcd_device *ld_dev)
116 { 116 {
117 return dev_get_drvdata(&ld_dev->dev); 117 return dev_get_drvdata(&ld_dev->dev);
118 } 118 }
119 119
120 120
121 #endif 121 #endif
122 122
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