xref: /linux-6.15/include/linux/leds.h (revision eb2bce7f)
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 
18 struct device;
19 struct class_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 	void		(*brightness_set)(struct led_classdev *led_cdev,
39 					  enum led_brightness brightness);
40 
41 	struct class_device	*class_dev;
42 	struct list_head	 node;			/* LED Device list */
43 	char			*default_trigger;	/* Trigger to use */
44 
45 #ifdef CONFIG_LEDS_TRIGGERS
46 	/* Protects the trigger data below */
47 	rwlock_t		 trigger_lock;
48 
49 	struct led_trigger	*trigger;
50 	struct list_head	 trig_list;
51 	void			*trigger_data;
52 #endif
53 };
54 
55 extern int led_classdev_register(struct device *parent,
56 				 struct led_classdev *led_cdev);
57 extern void led_classdev_unregister(struct led_classdev *led_cdev);
58 extern void led_classdev_suspend(struct led_classdev *led_cdev);
59 extern void led_classdev_resume(struct led_classdev *led_cdev);
60 
61 /*
62  * LED Triggers
63  */
64 #ifdef CONFIG_LEDS_TRIGGERS
65 
66 #define TRIG_NAME_MAX 50
67 
68 struct led_trigger {
69 	/* Trigger Properties */
70 	const char	 *name;
71 	void		(*activate)(struct led_classdev *led_cdev);
72 	void		(*deactivate)(struct led_classdev *led_cdev);
73 
74 	/* LEDs under control by this trigger (for simple triggers) */
75 	rwlock_t	  leddev_list_lock;
76 	struct list_head  led_cdevs;
77 
78 	/* Link to next registered trigger */
79 	struct list_head  next_trig;
80 };
81 
82 /* Registration functions for complex triggers */
83 extern int led_trigger_register(struct led_trigger *trigger);
84 extern void led_trigger_unregister(struct led_trigger *trigger);
85 
86 /* Registration functions for simple triggers */
87 #define DEFINE_LED_TRIGGER(x)		static struct led_trigger *x;
88 #define DEFINE_LED_TRIGGER_GLOBAL(x)	struct led_trigger *x;
89 extern void led_trigger_register_simple(const char *name,
90 				struct led_trigger **trigger);
91 extern void led_trigger_unregister_simple(struct led_trigger *trigger);
92 extern void led_trigger_event(struct led_trigger *trigger,
93 				enum led_brightness event);
94 
95 #else
96 
97 /* Triggers aren't active - null macros */
98 #define DEFINE_LED_TRIGGER(x)
99 #define DEFINE_LED_TRIGGER_GLOBAL(x)
100 #define led_trigger_register_simple(x, y) do {} while(0)
101 #define led_trigger_unregister_simple(x) do {} while(0)
102 #define led_trigger_event(x, y) do {} while(0)
103 
104 #endif
105 
106 /* Trigger specific functions */
107 #ifdef CONFIG_LEDS_TRIGGER_IDE_DISK
108 extern void ledtrig_ide_activity(void);
109 #else
110 #define ledtrig_ide_activity() do {} while(0)
111 #endif
112 
113 #endif		/* __LINUX_LEDS_H_INCLUDED */
114