1/*
2 * Driver model for leds and led triggers
3 *
4 * Copyright (C) 2005 John Lenz <lenz@cs.wisc.edu>
5 * Copyright (C) 2005 Richard Purdie <rpurdie@openedhand.com>
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/mutex.h>
17#include <linux/rwsem.h>
18#include <linux/spinlock.h>
19#include <linux/timer.h>
20#include <linux/workqueue.h>
21
22struct device;
23/*
24 * LED Core
25 */
26
27enum led_brightness {
28	LED_OFF		= 0,
29	LED_HALF	= 127,
30	LED_FULL	= 255,
31};
32
33struct led_classdev {
34	const char		*name;
35	enum led_brightness	 brightness;
36	enum led_brightness	 max_brightness;
37	int			 flags;
38
39	/* Lower 16 bits reflect status */
40#define LED_SUSPENDED		(1 << 0)
41	/* Upper 16 bits reflect control information */
42#define LED_CORE_SUSPENDRESUME	(1 << 16)
43#define LED_BLINK_ONESHOT	(1 << 17)
44#define LED_BLINK_ONESHOT_STOP	(1 << 18)
45#define LED_BLINK_INVERT	(1 << 19)
46#define LED_SYSFS_DISABLE	(1 << 20)
47#define SET_BRIGHTNESS_ASYNC	(1 << 21)
48#define SET_BRIGHTNESS_SYNC	(1 << 22)
49#define LED_DEV_CAP_FLASH	(1 << 23)
50
51	/* Set LED brightness level */
52	/* Must not sleep, use a workqueue if needed */
53	void		(*brightness_set)(struct led_classdev *led_cdev,
54					  enum led_brightness brightness);
55	/*
56	 * Set LED brightness level immediately - it can block the caller for
57	 * the time required for accessing a LED device register.
58	 */
59	int		(*brightness_set_sync)(struct led_classdev *led_cdev,
60					enum led_brightness brightness);
61	/* Get LED brightness level */
62	enum led_brightness (*brightness_get)(struct led_classdev *led_cdev);
63
64	/*
65	 * Activate hardware accelerated blink, delays are in milliseconds
66	 * and if both are zero then a sensible default should be chosen.
67	 * The call should adjust the timings in that case and if it can't
68	 * match the values specified exactly.
69	 * Deactivate blinking again when the brightness is set to a fixed
70	 * value via the brightness_set() callback.
71	 */
72	int		(*blink_set)(struct led_classdev *led_cdev,
73				     unsigned long *delay_on,
74				     unsigned long *delay_off);
75
76	struct device		*dev;
77	const struct attribute_group	**groups;
78
79	struct list_head	 node;			/* LED Device list */
80	const char		*default_trigger;	/* Trigger to use */
81
82	unsigned long		 blink_delay_on, blink_delay_off;
83	struct timer_list	 blink_timer;
84	int			 blink_brightness;
85	void			(*flash_resume)(struct led_classdev *led_cdev);
86
87	struct work_struct	set_brightness_work;
88	int			delayed_set_value;
89
90#ifdef CONFIG_LEDS_TRIGGERS
91	/* Protects the trigger data below */
92	struct rw_semaphore	 trigger_lock;
93
94	struct led_trigger	*trigger;
95	struct list_head	 trig_list;
96	void			*trigger_data;
97	/* true if activated - deactivate routine uses it to do cleanup */
98	bool			activated;
99#endif
100
101	/* Ensures consistent access to the LED Flash Class device */
102	struct mutex		led_access;
103};
104
105extern int led_classdev_register(struct device *parent,
106				 struct led_classdev *led_cdev);
107extern int devm_led_classdev_register(struct device *parent,
108				      struct led_classdev *led_cdev);
109extern void led_classdev_unregister(struct led_classdev *led_cdev);
110extern void devm_led_classdev_unregister(struct device *parent,
111					 struct led_classdev *led_cdev);
112extern void led_classdev_suspend(struct led_classdev *led_cdev);
113extern void led_classdev_resume(struct led_classdev *led_cdev);
114
115/**
116 * led_blink_set - set blinking with software fallback
117 * @led_cdev: the LED to start blinking
118 * @delay_on: the time it should be on (in ms)
119 * @delay_off: the time it should ble off (in ms)
120 *
121 * This function makes the LED blink, attempting to use the
122 * hardware acceleration if possible, but falling back to
123 * software blinking if there is no hardware blinking or if
124 * the LED refuses the passed values.
125 *
126 * Note that if software blinking is active, simply calling
127 * led_cdev->brightness_set() will not stop the blinking,
128 * use led_classdev_brightness_set() instead.
129 */
130extern void led_blink_set(struct led_classdev *led_cdev,
131			  unsigned long *delay_on,
132			  unsigned long *delay_off);
133/**
134 * led_blink_set_oneshot - do a oneshot software blink
135 * @led_cdev: the LED to start blinking
136 * @delay_on: the time it should be on (in ms)
137 * @delay_off: the time it should ble off (in ms)
138 * @invert: blink off, then on, leaving the led on
139 *
140 * This function makes the LED blink one time for delay_on +
141 * delay_off time, ignoring the request if another one-shot
142 * blink is already in progress.
143 *
144 * If invert is set, led blinks for delay_off first, then for
145 * delay_on and leave the led on after the on-off cycle.
146 */
147extern void led_blink_set_oneshot(struct led_classdev *led_cdev,
148				  unsigned long *delay_on,
149				  unsigned long *delay_off,
150				  int invert);
151/**
152 * led_set_brightness - set LED brightness
153 * @led_cdev: the LED to set
154 * @brightness: the brightness to set it to
155 *
156 * Set an LED's brightness, and, if necessary, cancel the
157 * software blink timer that implements blinking when the
158 * hardware doesn't.
159 */
160extern void led_set_brightness(struct led_classdev *led_cdev,
161			       enum led_brightness brightness);
162/**
163 * led_update_brightness - update LED brightness
164 * @led_cdev: the LED to query
165 *
166 * Get an LED's current brightness and update led_cdev->brightness
167 * member with the obtained value.
168 *
169 * Returns: 0 on success or negative error value on failure
170 */
171extern int led_update_brightness(struct led_classdev *led_cdev);
172
173/**
174 * led_sysfs_disable - disable LED sysfs interface
175 * @led_cdev: the LED to set
176 *
177 * Disable the led_cdev's sysfs interface.
178 */
179extern void led_sysfs_disable(struct led_classdev *led_cdev);
180
181/**
182 * led_sysfs_enable - enable LED sysfs interface
183 * @led_cdev: the LED to set
184 *
185 * Enable the led_cdev's sysfs interface.
186 */
187extern void led_sysfs_enable(struct led_classdev *led_cdev);
188
189/**
190 * led_sysfs_is_disabled - check if LED sysfs interface is disabled
191 * @led_cdev: the LED to query
192 *
193 * Returns: true if the led_cdev's sysfs interface is disabled.
194 */
195static inline bool led_sysfs_is_disabled(struct led_classdev *led_cdev)
196{
197	return led_cdev->flags & LED_SYSFS_DISABLE;
198}
199
200/*
201 * LED Triggers
202 */
203/* Registration functions for simple triggers */
204#define DEFINE_LED_TRIGGER(x)		static struct led_trigger *x;
205#define DEFINE_LED_TRIGGER_GLOBAL(x)	struct led_trigger *x;
206
207#ifdef CONFIG_LEDS_TRIGGERS
208
209#define TRIG_NAME_MAX 50
210
211struct led_trigger {
212	/* Trigger Properties */
213	const char	 *name;
214	void		(*activate)(struct led_classdev *led_cdev);
215	void		(*deactivate)(struct led_classdev *led_cdev);
216
217	/* LEDs under control by this trigger (for simple triggers) */
218	rwlock_t	  leddev_list_lock;
219	struct list_head  led_cdevs;
220
221	/* Link to next registered trigger */
222	struct list_head  next_trig;
223};
224
225/* Registration functions for complex triggers */
226extern int led_trigger_register(struct led_trigger *trigger);
227extern void led_trigger_unregister(struct led_trigger *trigger);
228
229extern void led_trigger_register_simple(const char *name,
230				struct led_trigger **trigger);
231extern void led_trigger_unregister_simple(struct led_trigger *trigger);
232extern void led_trigger_event(struct led_trigger *trigger,
233				enum led_brightness event);
234extern void led_trigger_blink(struct led_trigger *trigger,
235			      unsigned long *delay_on,
236			      unsigned long *delay_off);
237extern void led_trigger_blink_oneshot(struct led_trigger *trigger,
238				      unsigned long *delay_on,
239				      unsigned long *delay_off,
240				      int invert);
241/**
242 * led_trigger_rename_static - rename a trigger
243 * @name: the new trigger name
244 * @trig: the LED trigger to rename
245 *
246 * Change a LED trigger name by copying the string passed in
247 * name into current trigger name, which MUST be large
248 * enough for the new string.
249 *
250 * Note that name must NOT point to the same string used
251 * during LED registration, as that could lead to races.
252 *
253 * This is meant to be used on triggers with statically
254 * allocated name.
255 */
256extern void led_trigger_rename_static(const char *name,
257				      struct led_trigger *trig);
258
259#else
260
261/* Trigger has no members */
262struct led_trigger {};
263
264/* Trigger inline empty functions */
265static inline void led_trigger_register_simple(const char *name,
266					struct led_trigger **trigger) {}
267static inline void led_trigger_unregister_simple(struct led_trigger *trigger) {}
268static inline void led_trigger_event(struct led_trigger *trigger,
269				enum led_brightness event) {}
270#endif /* CONFIG_LEDS_TRIGGERS */
271
272/* Trigger specific functions */
273#ifdef CONFIG_LEDS_TRIGGER_IDE_DISK
274extern void ledtrig_ide_activity(void);
275#else
276static inline void ledtrig_ide_activity(void) {}
277#endif
278
279#if defined(CONFIG_LEDS_TRIGGER_CAMERA) || defined(CONFIG_LEDS_TRIGGER_CAMERA_MODULE)
280extern void ledtrig_flash_ctrl(bool on);
281extern void ledtrig_torch_ctrl(bool on);
282#else
283static inline void ledtrig_flash_ctrl(bool on) {}
284static inline void ledtrig_torch_ctrl(bool on) {}
285#endif
286
287/*
288 * Generic LED platform data for describing LED names and default triggers.
289 */
290struct led_info {
291	const char	*name;
292	const char	*default_trigger;
293	int		flags;
294};
295
296struct led_platform_data {
297	int		num_leds;
298	struct led_info	*leds;
299};
300
301/* For the leds-gpio driver */
302struct gpio_led {
303	const char *name;
304	const char *default_trigger;
305	unsigned 	gpio;
306	unsigned	active_low : 1;
307	unsigned	retain_state_suspended : 1;
308	unsigned	default_state : 2;
309	/* default_state should be one of LEDS_GPIO_DEFSTATE_(ON|OFF|KEEP) */
310	struct gpio_desc *gpiod;
311};
312#define LEDS_GPIO_DEFSTATE_OFF		0
313#define LEDS_GPIO_DEFSTATE_ON		1
314#define LEDS_GPIO_DEFSTATE_KEEP		2
315
316struct gpio_led_platform_data {
317	int 		num_leds;
318	const struct gpio_led *leds;
319
320#define GPIO_LED_NO_BLINK_LOW	0	/* No blink GPIO state low */
321#define GPIO_LED_NO_BLINK_HIGH	1	/* No blink GPIO state high */
322#define GPIO_LED_BLINK		2	/* Please, blink */
323	int		(*gpio_blink_set)(struct gpio_desc *desc, int state,
324					unsigned long *delay_on,
325					unsigned long *delay_off);
326};
327
328struct platform_device *gpio_led_register_device(
329		int id, const struct gpio_led_platform_data *pdata);
330
331enum cpu_led_event {
332	CPU_LED_IDLE_START,	/* CPU enters idle */
333	CPU_LED_IDLE_END,	/* CPU idle ends */
334	CPU_LED_START,		/* Machine starts, especially resume */
335	CPU_LED_STOP,		/* Machine stops, especially suspend */
336	CPU_LED_HALTED,		/* Machine shutdown */
337};
338#ifdef CONFIG_LEDS_TRIGGER_CPU
339extern void ledtrig_cpu(enum cpu_led_event evt);
340#else
341static inline void ledtrig_cpu(enum cpu_led_event evt)
342{
343	return;
344}
345#endif
346
347#endif		/* __LINUX_LEDS_H_INCLUDED */
348