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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/device.h>
16#include <linux/list.h>
17#include <linux/mutex.h>
18#include <linux/rwsem.h>
19#include <linux/spinlock.h>
20#include <linux/timer.h>
21#include <linux/workqueue.h>
22
23struct device;
24/*
25 * LED Core
26 */
27
28enum led_brightness {
29 LED_OFF = 0,
30 LED_HALF = 127,
31 LED_FULL = 255,
32};
33
34struct led_classdev {
35 const char *name;
36 enum led_brightness brightness;
37 enum led_brightness max_brightness;
38 int flags;
39
40 /* Lower 16 bits reflect status */
41#define LED_SUSPENDED (1 << 0)
42#define LED_UNREGISTERING (1 << 1)
43 /* Upper 16 bits reflect control information */
44#define LED_CORE_SUSPENDRESUME (1 << 16)
45#define LED_BLINK_ONESHOT (1 << 17)
46#define LED_BLINK_ONESHOT_STOP (1 << 18)
47#define LED_BLINK_INVERT (1 << 19)
48#define LED_BLINK_BRIGHTNESS_CHANGE (1 << 20)
49#define LED_BLINK_DISABLE (1 << 21)
50#define LED_SYSFS_DISABLE (1 << 22)
51#define LED_DEV_CAP_FLASH (1 << 23)
52#define LED_HW_PLUGGABLE (1 << 24)
53#define LED_PANIC_INDICATOR (1 << 25)
54
55 /* Set LED brightness level
56 * Must not sleep. Use brightness_set_blocking for drivers
57 * that can sleep while setting brightness.
58 */
59 void (*brightness_set)(struct led_classdev *led_cdev,
60 enum led_brightness brightness);
61 /*
62 * Set LED brightness level immediately - it can block the caller for
63 * the time required for accessing a LED device register.
64 */
65 int (*brightness_set_blocking)(struct led_classdev *led_cdev,
66 enum led_brightness brightness);
67 /* Get LED brightness level */
68 enum led_brightness (*brightness_get)(struct led_classdev *led_cdev);
69
70 /*
71 * Activate hardware accelerated blink, delays are in milliseconds
72 * and if both are zero then a sensible default should be chosen.
73 * The call should adjust the timings in that case and if it can't
74 * match the values specified exactly.
75 * Deactivate blinking again when the brightness is set to a fixed
76 * value via the brightness_set() callback.
77 */
78 int (*blink_set)(struct led_classdev *led_cdev,
79 unsigned long *delay_on,
80 unsigned long *delay_off);
81
82 struct device *dev;
83 const struct attribute_group **groups;
84
85 struct list_head node; /* LED Device list */
86 const char *default_trigger; /* Trigger to use */
87
88 unsigned long blink_delay_on, blink_delay_off;
89 struct timer_list blink_timer;
90 int blink_brightness;
91 void (*flash_resume)(struct led_classdev *led_cdev);
92
93 struct work_struct set_brightness_work;
94 int delayed_set_value;
95
96#ifdef CONFIG_LEDS_TRIGGERS
97 /* Protects the trigger data below */
98 struct rw_semaphore trigger_lock;
99
100 struct led_trigger *trigger;
101 struct list_head trig_list;
102 void *trigger_data;
103 /* true if activated - deactivate routine uses it to do cleanup */
104 bool activated;
105#endif
106
107 /* Ensures consistent access to the LED Flash Class device */
108 struct mutex led_access;
109};
110
111extern int led_classdev_register(struct device *parent,
112 struct led_classdev *led_cdev);
113extern int devm_led_classdev_register(struct device *parent,
114 struct led_classdev *led_cdev);
115extern void led_classdev_unregister(struct led_classdev *led_cdev);
116extern void devm_led_classdev_unregister(struct device *parent,
117 struct led_classdev *led_cdev);
118extern void led_classdev_suspend(struct led_classdev *led_cdev);
119extern void led_classdev_resume(struct led_classdev *led_cdev);
120
121/**
122 * led_blink_set - set blinking with software fallback
123 * @led_cdev: the LED to start blinking
124 * @delay_on: the time it should be on (in ms)
125 * @delay_off: the time it should ble off (in ms)
126 *
127 * This function makes the LED blink, attempting to use the
128 * hardware acceleration if possible, but falling back to
129 * software blinking if there is no hardware blinking or if
130 * the LED refuses the passed values.
131 *
132 * Note that if software blinking is active, simply calling
133 * led_cdev->brightness_set() will not stop the blinking,
134 * use led_classdev_brightness_set() instead.
135 */
136extern void led_blink_set(struct led_classdev *led_cdev,
137 unsigned long *delay_on,
138 unsigned long *delay_off);
139/**
140 * led_blink_set_oneshot - do a oneshot software blink
141 * @led_cdev: the LED to start blinking
142 * @delay_on: the time it should be on (in ms)
143 * @delay_off: the time it should ble off (in ms)
144 * @invert: blink off, then on, leaving the led on
145 *
146 * This function makes the LED blink one time for delay_on +
147 * delay_off time, ignoring the request if another one-shot
148 * blink is already in progress.
149 *
150 * If invert is set, led blinks for delay_off first, then for
151 * delay_on and leave the led on after the on-off cycle.
152 */
153extern void led_blink_set_oneshot(struct led_classdev *led_cdev,
154 unsigned long *delay_on,
155 unsigned long *delay_off,
156 int invert);
157/**
158 * led_set_brightness - set LED brightness
159 * @led_cdev: the LED to set
160 * @brightness: the brightness to set it to
161 *
162 * Set an LED's brightness, and, if necessary, cancel the
163 * software blink timer that implements blinking when the
164 * hardware doesn't. This function is guaranteed not to sleep.
165 */
166extern void led_set_brightness(struct led_classdev *led_cdev,
167 enum led_brightness brightness);
168
169/**
170 * led_set_brightness_sync - set LED brightness synchronously
171 * @led_cdev: the LED to set
172 * @brightness: the brightness to set it to
173 *
174 * Set an LED's brightness immediately. This function will block
175 * the caller for the time required for accessing device registers,
176 * and it can sleep.
177 *
178 * Returns: 0 on success or negative error value on failure
179 */
180extern int led_set_brightness_sync(struct led_classdev *led_cdev,
181 enum led_brightness value);
182
183/**
184 * led_update_brightness - update LED brightness
185 * @led_cdev: the LED to query
186 *
187 * Get an LED's current brightness and update led_cdev->brightness
188 * member with the obtained value.
189 *
190 * Returns: 0 on success or negative error value on failure
191 */
192extern int led_update_brightness(struct led_classdev *led_cdev);
193
194/**
195 * led_sysfs_disable - disable LED sysfs interface
196 * @led_cdev: the LED to set
197 *
198 * Disable the led_cdev's sysfs interface.
199 */
200extern void led_sysfs_disable(struct led_classdev *led_cdev);
201
202/**
203 * led_sysfs_enable - enable LED sysfs interface
204 * @led_cdev: the LED to set
205 *
206 * Enable the led_cdev's sysfs interface.
207 */
208extern void led_sysfs_enable(struct led_classdev *led_cdev);
209
210/**
211 * led_sysfs_is_disabled - check if LED sysfs interface is disabled
212 * @led_cdev: the LED to query
213 *
214 * Returns: true if the led_cdev's sysfs interface is disabled.
215 */
216static inline bool led_sysfs_is_disabled(struct led_classdev *led_cdev)
217{
218 return led_cdev->flags & LED_SYSFS_DISABLE;
219}
220
221/*
222 * LED Triggers
223 */
224/* Registration functions for simple triggers */
225#define DEFINE_LED_TRIGGER(x) static struct led_trigger *x;
226#define DEFINE_LED_TRIGGER_GLOBAL(x) struct led_trigger *x;
227
228#ifdef CONFIG_LEDS_TRIGGERS
229
230#define TRIG_NAME_MAX 50
231
232struct led_trigger {
233 /* Trigger Properties */
234 const char *name;
235 void (*activate)(struct led_classdev *led_cdev);
236 void (*deactivate)(struct led_classdev *led_cdev);
237
238 /* LEDs under control by this trigger (for simple triggers) */
239 rwlock_t leddev_list_lock;
240 struct list_head led_cdevs;
241
242 /* Link to next registered trigger */
243 struct list_head next_trig;
244};
245
246ssize_t led_trigger_store(struct device *dev, struct device_attribute *attr,
247 const char *buf, size_t count);
248ssize_t led_trigger_show(struct device *dev, struct device_attribute *attr,
249 char *buf);
250
251/* Registration functions for complex triggers */
252extern int led_trigger_register(struct led_trigger *trigger);
253extern void led_trigger_unregister(struct led_trigger *trigger);
254extern int devm_led_trigger_register(struct device *dev,
255 struct led_trigger *trigger);
256
257extern void led_trigger_register_simple(const char *name,
258 struct led_trigger **trigger);
259extern void led_trigger_unregister_simple(struct led_trigger *trigger);
260extern void led_trigger_event(struct led_trigger *trigger,
261 enum led_brightness event);
262extern void led_trigger_blink(struct led_trigger *trigger,
263 unsigned long *delay_on,
264 unsigned long *delay_off);
265extern void led_trigger_blink_oneshot(struct led_trigger *trigger,
266 unsigned long *delay_on,
267 unsigned long *delay_off,
268 int invert);
269extern void led_trigger_set_default(struct led_classdev *led_cdev);
270extern void led_trigger_set(struct led_classdev *led_cdev,
271 struct led_trigger *trigger);
272extern void led_trigger_remove(struct led_classdev *led_cdev);
273
274static inline void *led_get_trigger_data(struct led_classdev *led_cdev)
275{
276 return led_cdev->trigger_data;
277}
278
279/**
280 * led_trigger_rename_static - rename a trigger
281 * @name: the new trigger name
282 * @trig: the LED trigger to rename
283 *
284 * Change a LED trigger name by copying the string passed in
285 * name into current trigger name, which MUST be large
286 * enough for the new string.
287 *
288 * Note that name must NOT point to the same string used
289 * during LED registration, as that could lead to races.
290 *
291 * This is meant to be used on triggers with statically
292 * allocated name.
293 */
294extern void led_trigger_rename_static(const char *name,
295 struct led_trigger *trig);
296
297#else
298
299/* Trigger has no members */
300struct led_trigger {};
301
302/* Trigger inline empty functions */
303static inline void led_trigger_register_simple(const char *name,
304 struct led_trigger **trigger) {}
305static inline void led_trigger_unregister_simple(struct led_trigger *trigger) {}
306static inline void led_trigger_event(struct led_trigger *trigger,
307 enum led_brightness event) {}
308static inline void led_trigger_blink(struct led_trigger *trigger,
309 unsigned long *delay_on,
310 unsigned long *delay_off) {}
311static inline void led_trigger_blink_oneshot(struct led_trigger *trigger,
312 unsigned long *delay_on,
313 unsigned long *delay_off,
314 int invert) {}
315static inline void led_trigger_set_default(struct led_classdev *led_cdev) {}
316static inline void led_trigger_set(struct led_classdev *led_cdev,
317 struct led_trigger *trigger) {}
318static inline void led_trigger_remove(struct led_classdev *led_cdev) {}
319static inline void *led_get_trigger_data(struct led_classdev *led_cdev)
320{
321 return NULL;
322}
323
324#endif /* CONFIG_LEDS_TRIGGERS */
325
326/* Trigger specific functions */
327#ifdef CONFIG_LEDS_TRIGGER_IDE_DISK
328extern void ledtrig_ide_activity(void);
329#else
330static inline void ledtrig_ide_activity(void) {}
331#endif
332
333#ifdef CONFIG_LEDS_TRIGGER_MTD
334extern void ledtrig_mtd_activity(void);
335#else
336static inline void ledtrig_mtd_activity(void) {}
337#endif
338
339#if defined(CONFIG_LEDS_TRIGGER_CAMERA) || defined(CONFIG_LEDS_TRIGGER_CAMERA_MODULE)
340extern void ledtrig_flash_ctrl(bool on);
341extern void ledtrig_torch_ctrl(bool on);
342#else
343static inline void ledtrig_flash_ctrl(bool on) {}
344static inline void ledtrig_torch_ctrl(bool on) {}
345#endif
346
347/*
348 * Generic LED platform data for describing LED names and default triggers.
349 */
350struct led_info {
351 const char *name;
352 const char *default_trigger;
353 int flags;
354};
355
356struct led_platform_data {
357 int num_leds;
358 struct led_info *leds;
359};
360
361/* For the leds-gpio driver */
362struct gpio_led {
363 const char *name;
364 const char *default_trigger;
365 unsigned gpio;
366 unsigned active_low : 1;
367 unsigned retain_state_suspended : 1;
368 unsigned panic_indicator : 1;
369 unsigned default_state : 2;
370 /* default_state should be one of LEDS_GPIO_DEFSTATE_(ON|OFF|KEEP) */
371 struct gpio_desc *gpiod;
372};
373#define LEDS_GPIO_DEFSTATE_OFF 0
374#define LEDS_GPIO_DEFSTATE_ON 1
375#define LEDS_GPIO_DEFSTATE_KEEP 2
376
377struct gpio_led_platform_data {
378 int num_leds;
379 const struct gpio_led *leds;
380
381#define GPIO_LED_NO_BLINK_LOW 0 /* No blink GPIO state low */
382#define GPIO_LED_NO_BLINK_HIGH 1 /* No blink GPIO state high */
383#define GPIO_LED_BLINK 2 /* Please, blink */
384 int (*gpio_blink_set)(struct gpio_desc *desc, int state,
385 unsigned long *delay_on,
386 unsigned long *delay_off);
387};
388
389struct platform_device *gpio_led_register_device(
390 int id, const struct gpio_led_platform_data *pdata);
391
392enum cpu_led_event {
393 CPU_LED_IDLE_START, /* CPU enters idle */
394 CPU_LED_IDLE_END, /* CPU idle ends */
395 CPU_LED_START, /* Machine starts, especially resume */
396 CPU_LED_STOP, /* Machine stops, especially suspend */
397 CPU_LED_HALTED, /* Machine shutdown */
398};
399#ifdef CONFIG_LEDS_TRIGGER_CPU
400extern void ledtrig_cpu(enum cpu_led_event evt);
401#else
402static inline void ledtrig_cpu(enum cpu_led_event evt)
403{
404 return;
405}
406#endif
407
408#endif /* __LINUX_LEDS_H_INCLUDED */