xref: /linux-6.15/include/linux/leds.h (revision 71ccc212)
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			 max_brightness;
34 	int			 flags;
35 
36 	/* Lower 16 bits reflect status */
37 #define LED_SUSPENDED		(1 << 0)
38 	/* Upper 16 bits reflect control information */
39 #define LED_CORE_SUSPENDRESUME	(1 << 16)
40 
41 	/* Set LED brightness level */
42 	/* Must not sleep, use a workqueue if needed */
43 	void		(*brightness_set)(struct led_classdev *led_cdev,
44 					  enum led_brightness brightness);
45 	/* Get LED brightness level */
46 	enum led_brightness (*brightness_get)(struct led_classdev *led_cdev);
47 
48 	/* Activate hardware accelerated blink, delays are in
49 	 * miliseconds and if none is provided then a sensible default
50 	 * should be chosen. The call can adjust the timings if it can't
51 	 * match the values specified exactly. */
52 	int		(*blink_set)(struct led_classdev *led_cdev,
53 				     unsigned long *delay_on,
54 				     unsigned long *delay_off);
55 
56 	struct device		*dev;
57 	struct list_head	 node;			/* LED Device list */
58 	const char		*default_trigger;	/* Trigger to use */
59 
60 #ifdef CONFIG_LEDS_TRIGGERS
61 	/* Protects the trigger data below */
62 	struct rw_semaphore	 trigger_lock;
63 
64 	struct led_trigger	*trigger;
65 	struct list_head	 trig_list;
66 	void			*trigger_data;
67 #endif
68 };
69 
70 extern int led_classdev_register(struct device *parent,
71 				 struct led_classdev *led_cdev);
72 extern void led_classdev_unregister(struct led_classdev *led_cdev);
73 extern void led_classdev_suspend(struct led_classdev *led_cdev);
74 extern void led_classdev_resume(struct led_classdev *led_cdev);
75 
76 /*
77  * LED Triggers
78  */
79 #ifdef CONFIG_LEDS_TRIGGERS
80 
81 #define TRIG_NAME_MAX 50
82 
83 struct led_trigger {
84 	/* Trigger Properties */
85 	const char	 *name;
86 	void		(*activate)(struct led_classdev *led_cdev);
87 	void		(*deactivate)(struct led_classdev *led_cdev);
88 
89 	/* LEDs under control by this trigger (for simple triggers) */
90 	rwlock_t	  leddev_list_lock;
91 	struct list_head  led_cdevs;
92 
93 	/* Link to next registered trigger */
94 	struct list_head  next_trig;
95 };
96 
97 /* Registration functions for complex triggers */
98 extern int led_trigger_register(struct led_trigger *trigger);
99 extern void led_trigger_unregister(struct led_trigger *trigger);
100 
101 /* Registration functions for simple triggers */
102 #define DEFINE_LED_TRIGGER(x)		static struct led_trigger *x;
103 #define DEFINE_LED_TRIGGER_GLOBAL(x)	struct led_trigger *x;
104 extern void led_trigger_register_simple(const char *name,
105 				struct led_trigger **trigger);
106 extern void led_trigger_unregister_simple(struct led_trigger *trigger);
107 extern void led_trigger_event(struct led_trigger *trigger,
108 				enum led_brightness event);
109 
110 #else
111 
112 /* Triggers aren't active - null macros */
113 #define DEFINE_LED_TRIGGER(x)
114 #define DEFINE_LED_TRIGGER_GLOBAL(x)
115 #define led_trigger_register_simple(x, y) do {} while(0)
116 #define led_trigger_unregister_simple(x) do {} while(0)
117 #define led_trigger_event(x, y) do {} while(0)
118 
119 #endif
120 
121 /* Trigger specific functions */
122 #ifdef CONFIG_LEDS_TRIGGER_IDE_DISK
123 extern void ledtrig_ide_activity(void);
124 #else
125 #define ledtrig_ide_activity() do {} while(0)
126 #endif
127 
128 /*
129  * Generic LED platform data for describing LED names and default triggers.
130  */
131 struct led_info {
132 	const char	*name;
133 	const char	*default_trigger;
134 	int		flags;
135 };
136 
137 struct led_platform_data {
138 	int		num_leds;
139 	struct led_info	*leds;
140 };
141 
142 /* For the leds-gpio driver */
143 struct gpio_led {
144 	const char *name;
145 	const char *default_trigger;
146 	unsigned 	gpio;
147 	unsigned	active_low : 1;
148 	unsigned	retain_state_suspended : 1;
149 	unsigned	default_state : 2;
150 	/* default_state should be one of LEDS_GPIO_DEFSTATE_(ON|OFF|KEEP) */
151 };
152 #define LEDS_GPIO_DEFSTATE_OFF		0
153 #define LEDS_GPIO_DEFSTATE_ON		1
154 #define LEDS_GPIO_DEFSTATE_KEEP		2
155 
156 struct gpio_led_platform_data {
157 	int 		num_leds;
158 	struct gpio_led *leds;
159 
160 #define GPIO_LED_NO_BLINK_LOW	0	/* No blink GPIO state low */
161 #define GPIO_LED_NO_BLINK_HIGH	1	/* No blink GPIO state high */
162 #define GPIO_LED_BLINK		2	/* Plase, blink */
163 	int		(*gpio_blink_set)(unsigned gpio, int state,
164 					unsigned long *delay_on,
165 					unsigned long *delay_off);
166 };
167 
168 
169 #endif		/* __LINUX_LEDS_H_INCLUDED */
170