xref: /linux-6.15/include/linux/leds.h (revision 17c324fa)
1 /*
2  * Driver model for leds and led triggers
3  *
4  * Copyright (C) 2005 John Lenz <[email protected]>
5  * Copyright (C) 2005 Richard Purdie <[email protected]>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  *
11  */
12 #ifndef __LINUX_LEDS_H_INCLUDED
13 #define __LINUX_LEDS_H_INCLUDED
14 
15 #include <linux/list.h>
16 #include <linux/spinlock.h>
17 #include <linux/rwsem.h>
18 
19 struct device;
20 /*
21  * LED Core
22  */
23 
24 enum led_brightness {
25 	LED_OFF		= 0,
26 	LED_HALF	= 127,
27 	LED_FULL	= 255,
28 };
29 
30 struct led_classdev {
31 	const char		*name;
32 	int			 brightness;
33 	int			 flags;
34 
35 #define LED_SUSPENDED		(1 << 0)
36 
37 	/* Set LED brightness level */
38 	/* Must not sleep, use a workqueue if needed */
39 	void		(*brightness_set)(struct led_classdev *led_cdev,
40 					  enum led_brightness brightness);
41 	/* Get LED brightness level */
42 	enum led_brightness (*brightness_get)(struct led_classdev *led_cdev);
43 
44 	/* Activate hardware accelerated blink */
45 	int		(*blink_set)(struct led_classdev *led_cdev,
46 				     unsigned long *delay_on,
47 				     unsigned long *delay_off);
48 
49 	struct device		*dev;
50 	struct list_head	 node;			/* LED Device list */
51 	const char		*default_trigger;	/* Trigger to use */
52 
53 #ifdef CONFIG_LEDS_TRIGGERS
54 	/* Protects the trigger data below */
55 	struct rw_semaphore	 trigger_lock;
56 
57 	struct led_trigger	*trigger;
58 	struct list_head	 trig_list;
59 	void			*trigger_data;
60 #endif
61 };
62 
63 extern int led_classdev_register(struct device *parent,
64 				 struct led_classdev *led_cdev);
65 extern void led_classdev_unregister(struct led_classdev *lcd);
66 extern void led_classdev_suspend(struct led_classdev *led_cdev);
67 extern void led_classdev_resume(struct led_classdev *led_cdev);
68 
69 /*
70  * LED Triggers
71  */
72 #ifdef CONFIG_LEDS_TRIGGERS
73 
74 #define TRIG_NAME_MAX 50
75 
76 struct led_trigger {
77 	/* Trigger Properties */
78 	const char	 *name;
79 	void		(*activate)(struct led_classdev *led_cdev);
80 	void		(*deactivate)(struct led_classdev *led_cdev);
81 
82 	/* LEDs under control by this trigger (for simple triggers) */
83 	rwlock_t	  leddev_list_lock;
84 	struct list_head  led_cdevs;
85 
86 	/* Link to next registered trigger */
87 	struct list_head  next_trig;
88 };
89 
90 /* Registration functions for complex triggers */
91 extern int led_trigger_register(struct led_trigger *trigger);
92 extern void led_trigger_unregister(struct led_trigger *trigger);
93 
94 /* Registration functions for simple triggers */
95 #define DEFINE_LED_TRIGGER(x)		static struct led_trigger *x;
96 #define DEFINE_LED_TRIGGER_GLOBAL(x)	struct led_trigger *x;
97 extern void led_trigger_register_simple(const char *name,
98 				struct led_trigger **trigger);
99 extern void led_trigger_unregister_simple(struct led_trigger *trigger);
100 extern void led_trigger_event(struct led_trigger *trigger,
101 				enum led_brightness event);
102 
103 #else
104 
105 /* Triggers aren't active - null macros */
106 #define DEFINE_LED_TRIGGER(x)
107 #define DEFINE_LED_TRIGGER_GLOBAL(x)
108 #define led_trigger_register_simple(x, y) do {} while(0)
109 #define led_trigger_unregister_simple(x) do {} while(0)
110 #define led_trigger_event(x, y) do {} while(0)
111 
112 #endif
113 
114 /* Trigger specific functions */
115 #ifdef CONFIG_LEDS_TRIGGER_IDE_DISK
116 extern void ledtrig_ide_activity(void);
117 #else
118 #define ledtrig_ide_activity() do {} while(0)
119 #endif
120 
121 /*
122  * Generic LED platform data for describing LED names and default triggers.
123  */
124 struct led_info {
125 	const char	*name;
126 	const char	*default_trigger;
127 	int		flags;
128 };
129 
130 struct led_platform_data {
131 	int		num_leds;
132 	struct led_info	*leds;
133 };
134 
135 /* For the leds-gpio driver */
136 struct gpio_led {
137 	const char *name;
138 	const char *default_trigger;
139 	unsigned 	gpio;
140 	u8 		active_low;
141 };
142 
143 struct gpio_led_platform_data {
144 	int 		num_leds;
145 	struct gpio_led *leds;
146 	int		(*gpio_blink_set)(unsigned gpio,
147 					unsigned long *delay_on,
148 					unsigned long *delay_off);
149 };
150 
151 
152 #endif		/* __LINUX_LEDS_H_INCLUDED */
153