2 * Driver model for leds and led triggers
4 * Copyright (C) 2005 John Lenz <lenz@cs.wisc.edu>
5 * Copyright (C) 2005 Richard Purdie <rpurdie@openedhand.com>
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.
12 #ifndef __LINUX_LEDS_H_INCLUDED
13 #define __LINUX_LEDS_H_INCLUDED
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>
36 enum led_brightness brightness;
37 enum led_brightness max_brightness;
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_SYSFS_DISABLE (1 << 17)
46 #define LED_DEV_CAP_FLASH (1 << 18)
47 #define LED_HW_PLUGGABLE (1 << 19)
48 #define LED_PANIC_INDICATOR (1 << 20)
50 /* set_brightness_work / blink_timer flags, atomic, private. */
51 unsigned long work_flags;
53 #define LED_BLINK_SW 0
54 #define LED_BLINK_ONESHOT 1
55 #define LED_BLINK_ONESHOT_STOP 2
56 #define LED_BLINK_INVERT 3
57 #define LED_BLINK_BRIGHTNESS_CHANGE 4
58 #define LED_BLINK_DISABLE 5
60 /* Set LED brightness level
61 * Must not sleep. Use brightness_set_blocking for drivers
62 * that can sleep while setting brightness.
64 void (*brightness_set)(struct led_classdev *led_cdev,
65 enum led_brightness brightness);
67 * Set LED brightness level immediately - it can block the caller for
68 * the time required for accessing a LED device register.
70 int (*brightness_set_blocking)(struct led_classdev *led_cdev,
71 enum led_brightness brightness);
72 /* Get LED brightness level */
73 enum led_brightness (*brightness_get)(struct led_classdev *led_cdev);
76 * Activate hardware accelerated blink, delays are in milliseconds
77 * and if both are zero then a sensible default should be chosen.
78 * The call should adjust the timings in that case and if it can't
79 * match the values specified exactly.
80 * Deactivate blinking again when the brightness is set to LED_OFF
81 * via the brightness_set() callback.
83 int (*blink_set)(struct led_classdev *led_cdev,
84 unsigned long *delay_on,
85 unsigned long *delay_off);
88 const struct attribute_group **groups;
90 struct list_head node; /* LED Device list */
91 const char *default_trigger; /* Trigger to use */
93 unsigned long blink_delay_on, blink_delay_off;
94 struct timer_list blink_timer;
96 int new_blink_brightness;
97 void (*flash_resume)(struct led_classdev *led_cdev);
99 struct work_struct set_brightness_work;
100 int delayed_set_value;
102 #ifdef CONFIG_LEDS_TRIGGERS
103 /* Protects the trigger data below */
104 struct rw_semaphore trigger_lock;
106 struct led_trigger *trigger;
107 struct list_head trig_list;
109 /* true if activated - deactivate routine uses it to do cleanup */
113 /* Ensures consistent access to the LED Flash Class device */
114 struct mutex led_access;
117 extern int led_classdev_register(struct device *parent,
118 struct led_classdev *led_cdev);
119 extern int devm_led_classdev_register(struct device *parent,
120 struct led_classdev *led_cdev);
121 extern void led_classdev_unregister(struct led_classdev *led_cdev);
122 extern void devm_led_classdev_unregister(struct device *parent,
123 struct led_classdev *led_cdev);
124 extern void led_classdev_suspend(struct led_classdev *led_cdev);
125 extern void led_classdev_resume(struct led_classdev *led_cdev);
128 * led_blink_set - set blinking with software fallback
129 * @led_cdev: the LED to start blinking
130 * @delay_on: the time it should be on (in ms)
131 * @delay_off: the time it should ble off (in ms)
133 * This function makes the LED blink, attempting to use the
134 * hardware acceleration if possible, but falling back to
135 * software blinking if there is no hardware blinking or if
136 * the LED refuses the passed values.
138 * Note that if software blinking is active, simply calling
139 * led_cdev->brightness_set() will not stop the blinking,
140 * use led_classdev_brightness_set() instead.
142 extern void led_blink_set(struct led_classdev *led_cdev,
143 unsigned long *delay_on,
144 unsigned long *delay_off);
146 * led_blink_set_oneshot - do a oneshot software blink
147 * @led_cdev: the LED to start blinking
148 * @delay_on: the time it should be on (in ms)
149 * @delay_off: the time it should ble off (in ms)
150 * @invert: blink off, then on, leaving the led on
152 * This function makes the LED blink one time for delay_on +
153 * delay_off time, ignoring the request if another one-shot
154 * blink is already in progress.
156 * If invert is set, led blinks for delay_off first, then for
157 * delay_on and leave the led on after the on-off cycle.
159 extern void led_blink_set_oneshot(struct led_classdev *led_cdev,
160 unsigned long *delay_on,
161 unsigned long *delay_off,
164 * led_set_brightness - set LED brightness
165 * @led_cdev: the LED to set
166 * @brightness: the brightness to set it to
168 * Set an LED's brightness, and, if necessary, cancel the
169 * software blink timer that implements blinking when the
170 * hardware doesn't. This function is guaranteed not to sleep.
172 extern void led_set_brightness(struct led_classdev *led_cdev,
173 enum led_brightness brightness);
176 * led_set_brightness_sync - set LED brightness synchronously
177 * @led_cdev: the LED to set
178 * @brightness: the brightness to set it to
180 * Set an LED's brightness immediately. This function will block
181 * the caller for the time required for accessing device registers,
184 * Returns: 0 on success or negative error value on failure
186 extern int led_set_brightness_sync(struct led_classdev *led_cdev,
187 enum led_brightness value);
190 * led_update_brightness - update LED brightness
191 * @led_cdev: the LED to query
193 * Get an LED's current brightness and update led_cdev->brightness
194 * member with the obtained value.
196 * Returns: 0 on success or negative error value on failure
198 extern int led_update_brightness(struct led_classdev *led_cdev);
201 * led_sysfs_disable - disable LED sysfs interface
202 * @led_cdev: the LED to set
204 * Disable the led_cdev's sysfs interface.
206 extern void led_sysfs_disable(struct led_classdev *led_cdev);
209 * led_sysfs_enable - enable LED sysfs interface
210 * @led_cdev: the LED to set
212 * Enable the led_cdev's sysfs interface.
214 extern void led_sysfs_enable(struct led_classdev *led_cdev);
217 * led_sysfs_is_disabled - check if LED sysfs interface is disabled
218 * @led_cdev: the LED to query
220 * Returns: true if the led_cdev's sysfs interface is disabled.
222 static inline bool led_sysfs_is_disabled(struct led_classdev *led_cdev)
224 return led_cdev->flags & LED_SYSFS_DISABLE;
230 /* Registration functions for simple triggers */
231 #define DEFINE_LED_TRIGGER(x) static struct led_trigger *x;
232 #define DEFINE_LED_TRIGGER_GLOBAL(x) struct led_trigger *x;
234 #ifdef CONFIG_LEDS_TRIGGERS
236 #define TRIG_NAME_MAX 50
239 /* Trigger Properties */
241 void (*activate)(struct led_classdev *led_cdev);
242 void (*deactivate)(struct led_classdev *led_cdev);
244 /* LEDs under control by this trigger (for simple triggers) */
245 rwlock_t leddev_list_lock;
246 struct list_head led_cdevs;
248 /* Link to next registered trigger */
249 struct list_head next_trig;
252 ssize_t led_trigger_store(struct device *dev, struct device_attribute *attr,
253 const char *buf, size_t count);
254 ssize_t led_trigger_show(struct device *dev, struct device_attribute *attr,
257 /* Registration functions for complex triggers */
258 extern int led_trigger_register(struct led_trigger *trigger);
259 extern void led_trigger_unregister(struct led_trigger *trigger);
260 extern int devm_led_trigger_register(struct device *dev,
261 struct led_trigger *trigger);
263 extern void led_trigger_register_simple(const char *name,
264 struct led_trigger **trigger);
265 extern void led_trigger_unregister_simple(struct led_trigger *trigger);
266 extern void led_trigger_event(struct led_trigger *trigger,
267 enum led_brightness event);
268 extern void led_trigger_blink(struct led_trigger *trigger,
269 unsigned long *delay_on,
270 unsigned long *delay_off);
271 extern void led_trigger_blink_oneshot(struct led_trigger *trigger,
272 unsigned long *delay_on,
273 unsigned long *delay_off,
275 extern void led_trigger_set_default(struct led_classdev *led_cdev);
276 extern void led_trigger_set(struct led_classdev *led_cdev,
277 struct led_trigger *trigger);
278 extern void led_trigger_remove(struct led_classdev *led_cdev);
280 static inline void *led_get_trigger_data(struct led_classdev *led_cdev)
282 return led_cdev->trigger_data;
286 * led_trigger_rename_static - rename a trigger
287 * @name: the new trigger name
288 * @trig: the LED trigger to rename
290 * Change a LED trigger name by copying the string passed in
291 * name into current trigger name, which MUST be large
292 * enough for the new string.
294 * Note that name must NOT point to the same string used
295 * during LED registration, as that could lead to races.
297 * This is meant to be used on triggers with statically
300 extern void led_trigger_rename_static(const char *name,
301 struct led_trigger *trig);
305 /* Trigger has no members */
306 struct led_trigger {};
308 /* Trigger inline empty functions */
309 static inline void led_trigger_register_simple(const char *name,
310 struct led_trigger **trigger) {}
311 static inline void led_trigger_unregister_simple(struct led_trigger *trigger) {}
312 static inline void led_trigger_event(struct led_trigger *trigger,
313 enum led_brightness event) {}
314 static inline void led_trigger_blink(struct led_trigger *trigger,
315 unsigned long *delay_on,
316 unsigned long *delay_off) {}
317 static inline void led_trigger_blink_oneshot(struct led_trigger *trigger,
318 unsigned long *delay_on,
319 unsigned long *delay_off,
321 static inline void led_trigger_set_default(struct led_classdev *led_cdev) {}
322 static inline void led_trigger_set(struct led_classdev *led_cdev,
323 struct led_trigger *trigger) {}
324 static inline void led_trigger_remove(struct led_classdev *led_cdev) {}
325 static inline void *led_get_trigger_data(struct led_classdev *led_cdev)
330 #endif /* CONFIG_LEDS_TRIGGERS */
332 /* Trigger specific functions */
333 #ifdef CONFIG_LEDS_TRIGGER_DISK
334 extern void ledtrig_disk_activity(void);
336 static inline void ledtrig_disk_activity(void) {}
339 #ifdef CONFIG_LEDS_TRIGGER_MTD
340 extern void ledtrig_mtd_activity(void);
342 static inline void ledtrig_mtd_activity(void) {}
345 #if defined(CONFIG_LEDS_TRIGGER_CAMERA) || defined(CONFIG_LEDS_TRIGGER_CAMERA_MODULE)
346 extern void ledtrig_flash_ctrl(bool on);
347 extern void ledtrig_torch_ctrl(bool on);
349 static inline void ledtrig_flash_ctrl(bool on) {}
350 static inline void ledtrig_torch_ctrl(bool on) {}
354 * Generic LED platform data for describing LED names and default triggers.
358 const char *default_trigger;
362 struct led_platform_data {
364 struct led_info *leds;
368 typedef int (*gpio_blink_set_t)(struct gpio_desc *desc, int state,
369 unsigned long *delay_on,
370 unsigned long *delay_off);
372 /* For the leds-gpio driver */
375 const char *default_trigger;
377 unsigned active_low : 1;
378 unsigned retain_state_suspended : 1;
379 unsigned panic_indicator : 1;
380 unsigned default_state : 2;
381 /* default_state should be one of LEDS_GPIO_DEFSTATE_(ON|OFF|KEEP) */
382 struct gpio_desc *gpiod;
384 #define LEDS_GPIO_DEFSTATE_OFF 0
385 #define LEDS_GPIO_DEFSTATE_ON 1
386 #define LEDS_GPIO_DEFSTATE_KEEP 2
388 struct gpio_led_platform_data {
390 const struct gpio_led *leds;
392 #define GPIO_LED_NO_BLINK_LOW 0 /* No blink GPIO state low */
393 #define GPIO_LED_NO_BLINK_HIGH 1 /* No blink GPIO state high */
394 #define GPIO_LED_BLINK 2 /* Please, blink */
395 gpio_blink_set_t gpio_blink_set;
398 #ifdef CONFIG_NEW_LEDS
399 struct platform_device *gpio_led_register_device(
400 int id, const struct gpio_led_platform_data *pdata);
402 static inline struct platform_device *gpio_led_register_device(
403 int id, const struct gpio_led_platform_data *pdata)
410 CPU_LED_IDLE_START, /* CPU enters idle */
411 CPU_LED_IDLE_END, /* CPU idle ends */
412 CPU_LED_START, /* Machine starts, especially resume */
413 CPU_LED_STOP, /* Machine stops, especially suspend */
414 CPU_LED_HALTED, /* Machine shutdown */
416 #ifdef CONFIG_LEDS_TRIGGER_CPU
417 extern void ledtrig_cpu(enum cpu_led_event evt);
419 static inline void ledtrig_cpu(enum cpu_led_event evt)
425 #endif /* __LINUX_LEDS_H_INCLUDED */