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