xref: /linux-6.15/include/linux/leds.h (revision 8802f616)
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 struct device;
16 struct class_device;
17 /*
18  * LED Core
19  */
20 
21 enum led_brightness {
22 	LED_OFF		= 0,
23 	LED_HALF	= 127,
24 	LED_FULL	= 255,
25 };
26 
27 struct led_classdev {
28 	const char		*name;
29 	int			 brightness;
30 	int			 flags;
31 
32 #define LED_SUSPENDED		(1 << 0)
33 
34 	/* Set LED brightness level */
35 	void		(*brightness_set)(struct led_classdev *led_cdev,
36 					  enum led_brightness brightness);
37 
38 	struct class_device	*class_dev;
39 	struct list_head	 node;			/* LED Device list */
40 	char			*default_trigger;	/* Trigger to use */
41 
42 #ifdef CONFIG_LEDS_TRIGGERS
43 	/* Protects the trigger data below */
44 	rwlock_t		 trigger_lock;
45 
46 	struct led_trigger	*trigger;
47 	struct list_head	 trig_list;
48 	void			*trigger_data;
49 #endif
50 };
51 
52 extern int led_classdev_register(struct device *parent,
53 				 struct led_classdev *led_cdev);
54 extern void led_classdev_unregister(struct led_classdev *led_cdev);
55 extern void led_classdev_suspend(struct led_classdev *led_cdev);
56 extern void led_classdev_resume(struct led_classdev *led_cdev);
57 
58 /*
59  * LED Triggers
60  */
61 #ifdef CONFIG_LEDS_TRIGGERS
62 
63 #define TRIG_NAME_MAX 50
64 
65 struct led_trigger {
66 	/* Trigger Properties */
67 	const char	 *name;
68 	void		(*activate)(struct led_classdev *led_cdev);
69 	void		(*deactivate)(struct led_classdev *led_cdev);
70 
71 	/* LEDs under control by this trigger (for simple triggers) */
72 	rwlock_t	  leddev_list_lock;
73 	struct list_head  led_cdevs;
74 
75 	/* Link to next registered trigger */
76 	struct list_head  next_trig;
77 };
78 
79 /* Registration functions for complex triggers */
80 extern int led_trigger_register(struct led_trigger *trigger);
81 extern void led_trigger_unregister(struct led_trigger *trigger);
82 
83 /* Registration functions for simple triggers */
84 #define DEFINE_LED_TRIGGER(x)		static struct led_trigger *x;
85 #define DEFINE_LED_TRIGGER_GLOBAL(x)	struct led_trigger *x;
86 extern void led_trigger_register_simple(const char *name,
87 				struct led_trigger **trigger);
88 extern void led_trigger_unregister_simple(struct led_trigger *trigger);
89 extern void led_trigger_event(struct led_trigger *trigger,
90 				enum led_brightness event);
91 
92 #else
93 
94 /* Triggers aren't active - null macros */
95 #define DEFINE_LED_TRIGGER(x)
96 #define DEFINE_LED_TRIGGER_GLOBAL(x)
97 #define led_trigger_register_simple(x, y) do {} while(0)
98 #define led_trigger_unregister_simple(x) do {} while(0)
99 #define led_trigger_event(x, y) do {} while(0)
100 
101 #endif
102 
103 /* Trigger specific functions */
104 #ifdef CONFIG_LEDS_TRIGGER_IDE_DISK
105 extern void ledtrig_ide_activity(void);
106 #else
107 #define ledtrig_ide_activity() do {} while(0)
108 #endif
109 
110 #endif		/* __LINUX_LEDS_H_INCLUDED */
111