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>
37 enum led_brightness brightness;
38 enum led_brightness max_brightness;
41 /* Lower 16 bits reflect status */
42 #define LED_SUSPENDED (1 << 0)
43 #define LED_UNREGISTERING (1 << 1)
44 /* Upper 16 bits reflect control information */
45 #define LED_CORE_SUSPENDRESUME (1 << 16)
46 #define LED_SYSFS_DISABLE (1 << 17)
47 #define LED_DEV_CAP_FLASH (1 << 18)
48 #define LED_HW_PLUGGABLE (1 << 19)
49 #define LED_PANIC_INDICATOR (1 << 20)
51 /* set_brightness_work / blink_timer flags, atomic, private. */
52 unsigned long work_flags;
54 #define LED_BLINK_SW 0
55 #define LED_BLINK_ONESHOT 1
56 #define LED_BLINK_ONESHOT_STOP 2
57 #define LED_BLINK_INVERT 3
58 #define LED_BLINK_BRIGHTNESS_CHANGE 4
59 #define LED_BLINK_DISABLE 5
61 /* Set LED brightness level
62 * Must not sleep. Use brightness_set_blocking for drivers
63 * that can sleep while setting brightness.
65 void (*brightness_set)(struct led_classdev *led_cdev,
66 enum led_brightness brightness);
68 * Set LED brightness level immediately - it can block the caller for
69 * the time required for accessing a LED device register.
71 int (*brightness_set_blocking)(struct led_classdev *led_cdev,
72 enum led_brightness brightness);
73 /* Get LED brightness level */
74 enum led_brightness (*brightness_get)(struct led_classdev *led_cdev);
77 * Activate hardware accelerated blink, delays are in milliseconds
78 * and if both are zero then a sensible default should be chosen.
79 * The call should adjust the timings in that case and if it can't
80 * match the values specified exactly.
81 * Deactivate blinking again when the brightness is set to LED_OFF
82 * via the brightness_set() callback.
84 int (*blink_set)(struct led_classdev *led_cdev,
85 unsigned long *delay_on,
86 unsigned long *delay_off);
89 const struct attribute_group **groups;
91 struct list_head node; /* LED Device list */
92 const char *default_trigger; /* Trigger to use */
94 unsigned long blink_delay_on, blink_delay_off;
95 struct timer_list blink_timer;
97 int new_blink_brightness;
98 void (*flash_resume)(struct led_classdev *led_cdev);
100 struct work_struct set_brightness_work;
101 int delayed_set_value;
103 #ifdef CONFIG_LEDS_TRIGGERS
104 /* Protects the trigger data below */
105 struct rw_semaphore trigger_lock;
107 struct led_trigger *trigger;
108 struct list_head trig_list;
110 /* true if activated - deactivate routine uses it to do cleanup */
114 /* Ensures consistent access to the LED Flash Class device */
115 struct mutex led_access;
118 extern int led_classdev_register(struct device *parent,
119 struct led_classdev *led_cdev);
120 extern int devm_led_classdev_register(struct device *parent,
121 struct led_classdev *led_cdev);
122 extern void led_classdev_unregister(struct led_classdev *led_cdev);
123 extern void devm_led_classdev_unregister(struct device *parent,
124 struct led_classdev *led_cdev);
125 extern void led_classdev_suspend(struct led_classdev *led_cdev);
126 extern void led_classdev_resume(struct led_classdev *led_cdev);
129 * led_blink_set - set blinking with software fallback
130 * @led_cdev: the LED to start blinking
131 * @delay_on: the time it should be on (in ms)
132 * @delay_off: the time it should ble off (in ms)
134 * This function makes the LED blink, attempting to use the
135 * hardware acceleration if possible, but falling back to
136 * software blinking if there is no hardware blinking or if
137 * the LED refuses the passed values.
139 * Note that if software blinking is active, simply calling
140 * led_cdev->brightness_set() will not stop the blinking,
141 * use led_classdev_brightness_set() instead.
143 extern void led_blink_set(struct led_classdev *led_cdev,
144 unsigned long *delay_on,
145 unsigned long *delay_off);
147 * led_blink_set_oneshot - do a oneshot software blink
148 * @led_cdev: the LED to start blinking
149 * @delay_on: the time it should be on (in ms)
150 * @delay_off: the time it should ble off (in ms)
151 * @invert: blink off, then on, leaving the led on
153 * This function makes the LED blink one time for delay_on +
154 * delay_off time, ignoring the request if another one-shot
155 * blink is already in progress.
157 * If invert is set, led blinks for delay_off first, then for
158 * delay_on and leave the led on after the on-off cycle.
160 extern void led_blink_set_oneshot(struct led_classdev *led_cdev,
161 unsigned long *delay_on,
162 unsigned long *delay_off,
165 * led_set_brightness - set LED brightness
166 * @led_cdev: the LED to set
167 * @brightness: the brightness to set it to
169 * Set an LED's brightness, and, if necessary, cancel the
170 * software blink timer that implements blinking when the
171 * hardware doesn't. This function is guaranteed not to sleep.
173 extern void led_set_brightness(struct led_classdev *led_cdev,
174 enum led_brightness brightness);
177 * led_set_brightness_sync - set LED brightness synchronously
178 * @led_cdev: the LED to set
179 * @brightness: the brightness to set it to
181 * Set an LED's brightness immediately. This function will block
182 * the caller for the time required for accessing device registers,
185 * Returns: 0 on success or negative error value on failure
187 extern int led_set_brightness_sync(struct led_classdev *led_cdev,
188 enum led_brightness value);
191 * led_update_brightness - update LED brightness
192 * @led_cdev: the LED to query
194 * Get an LED's current brightness and update led_cdev->brightness
195 * member with the obtained value.
197 * Returns: 0 on success or negative error value on failure
199 extern int led_update_brightness(struct led_classdev *led_cdev);
202 * led_sysfs_disable - disable LED sysfs interface
203 * @led_cdev: the LED to set
205 * Disable the led_cdev's sysfs interface.
207 extern void led_sysfs_disable(struct led_classdev *led_cdev);
210 * led_sysfs_enable - enable LED sysfs interface
211 * @led_cdev: the LED to set
213 * Enable the led_cdev's sysfs interface.
215 extern void led_sysfs_enable(struct led_classdev *led_cdev);
218 * led_sysfs_is_disabled - check if LED sysfs interface is disabled
219 * @led_cdev: the LED to query
221 * Returns: true if the led_cdev's sysfs interface is disabled.
223 static inline bool led_sysfs_is_disabled(struct led_classdev *led_cdev)
225 return led_cdev->flags & LED_SYSFS_DISABLE;
231 /* Registration functions for simple triggers */
232 #define DEFINE_LED_TRIGGER(x) static struct led_trigger *x;
233 #define DEFINE_LED_TRIGGER_GLOBAL(x) struct led_trigger *x;
235 #ifdef CONFIG_LEDS_TRIGGERS
237 #define TRIG_NAME_MAX 50
240 /* Trigger Properties */
242 void (*activate)(struct led_classdev *led_cdev);
243 void (*deactivate)(struct led_classdev *led_cdev);
245 /* LEDs under control by this trigger (for simple triggers) */
246 rwlock_t leddev_list_lock;
247 struct list_head led_cdevs;
249 /* Link to next registered trigger */
250 struct list_head next_trig;
253 ssize_t led_trigger_store(struct device *dev, struct device_attribute *attr,
254 const char *buf, size_t count);
255 ssize_t led_trigger_show(struct device *dev, struct device_attribute *attr,
258 /* Registration functions for complex triggers */
259 extern int led_trigger_register(struct led_trigger *trigger);
260 extern void led_trigger_unregister(struct led_trigger *trigger);
261 extern int devm_led_trigger_register(struct device *dev,
262 struct led_trigger *trigger);
264 extern void led_trigger_register_simple(const char *name,
265 struct led_trigger **trigger);
266 extern void led_trigger_unregister_simple(struct led_trigger *trigger);
267 extern void led_trigger_event(struct led_trigger *trigger,
268 enum led_brightness event);
269 extern void led_trigger_blink(struct led_trigger *trigger,
270 unsigned long *delay_on,
271 unsigned long *delay_off);
272 extern void led_trigger_blink_oneshot(struct led_trigger *trigger,
273 unsigned long *delay_on,
274 unsigned long *delay_off,
276 extern void led_trigger_set_default(struct led_classdev *led_cdev);
277 extern void led_trigger_set(struct led_classdev *led_cdev,
278 struct led_trigger *trigger);
279 extern void led_trigger_remove(struct led_classdev *led_cdev);
281 static inline void *led_get_trigger_data(struct led_classdev *led_cdev)
283 return led_cdev->trigger_data;
287 * led_trigger_rename_static - rename a trigger
288 * @name: the new trigger name
289 * @trig: the LED trigger to rename
291 * Change a LED trigger name by copying the string passed in
292 * name into current trigger name, which MUST be large
293 * enough for the new string.
295 * Note that name must NOT point to the same string used
296 * during LED registration, as that could lead to races.
298 * This is meant to be used on triggers with statically
301 extern void led_trigger_rename_static(const char *name,
302 struct led_trigger *trig);
306 /* Trigger has no members */
307 struct led_trigger {};
309 /* Trigger inline empty functions */
310 static inline void led_trigger_register_simple(const char *name,
311 struct led_trigger **trigger) {}
312 static inline void led_trigger_unregister_simple(struct led_trigger *trigger) {}
313 static inline void led_trigger_event(struct led_trigger *trigger,
314 enum led_brightness event) {}
315 static inline void led_trigger_blink(struct led_trigger *trigger,
316 unsigned long *delay_on,
317 unsigned long *delay_off) {}
318 static inline void led_trigger_blink_oneshot(struct led_trigger *trigger,
319 unsigned long *delay_on,
320 unsigned long *delay_off,
322 static inline void led_trigger_set_default(struct led_classdev *led_cdev) {}
323 static inline void led_trigger_set(struct led_classdev *led_cdev,
324 struct led_trigger *trigger) {}
325 static inline void led_trigger_remove(struct led_classdev *led_cdev) {}
326 static inline void *led_get_trigger_data(struct led_classdev *led_cdev)
331 #endif /* CONFIG_LEDS_TRIGGERS */
333 /* Trigger specific functions */
334 #ifdef CONFIG_LEDS_TRIGGER_DISK
335 extern void ledtrig_disk_activity(void);
337 static inline void ledtrig_disk_activity(void) {}
340 #ifdef CONFIG_LEDS_TRIGGER_MTD
341 extern void ledtrig_mtd_activity(void);
343 static inline void ledtrig_mtd_activity(void) {}
346 #if defined(CONFIG_LEDS_TRIGGER_CAMERA) || defined(CONFIG_LEDS_TRIGGER_CAMERA_MODULE)
347 extern void ledtrig_flash_ctrl(bool on);
348 extern void ledtrig_torch_ctrl(bool on);
350 static inline void ledtrig_flash_ctrl(bool on) {}
351 static inline void ledtrig_torch_ctrl(bool on) {}
355 * Generic LED platform data for describing LED names and default triggers.
359 const char *default_trigger;
363 struct led_platform_data {
365 struct led_info *leds;
369 typedef int (*gpio_blink_set_t)(struct gpio_desc *desc, int state,
370 unsigned long *delay_on,
371 unsigned long *delay_off);
373 /* For the leds-gpio driver */
376 const char *default_trigger;
378 unsigned active_low : 1;
379 unsigned retain_state_suspended : 1;
380 unsigned panic_indicator : 1;
381 unsigned default_state : 2;
382 /* default_state should be one of LEDS_GPIO_DEFSTATE_(ON|OFF|KEEP) */
383 struct gpio_desc *gpiod;
385 #define LEDS_GPIO_DEFSTATE_OFF 0
386 #define LEDS_GPIO_DEFSTATE_ON 1
387 #define LEDS_GPIO_DEFSTATE_KEEP 2
389 struct gpio_led_platform_data {
391 const struct gpio_led *leds;
393 #define GPIO_LED_NO_BLINK_LOW 0 /* No blink GPIO state low */
394 #define GPIO_LED_NO_BLINK_HIGH 1 /* No blink GPIO state high */
395 #define GPIO_LED_BLINK 2 /* Please, blink */
396 gpio_blink_set_t gpio_blink_set;
399 #ifdef CONFIG_NEW_LEDS
400 struct platform_device *gpio_led_register_device(
401 int id, const struct gpio_led_platform_data *pdata);
403 static inline struct platform_device *gpio_led_register_device(
404 int id, const struct gpio_led_platform_data *pdata)
411 CPU_LED_IDLE_START, /* CPU enters idle */
412 CPU_LED_IDLE_END, /* CPU idle ends */
413 CPU_LED_START, /* Machine starts, especially resume */
414 CPU_LED_STOP, /* Machine stops, especially suspend */
415 CPU_LED_HALTED, /* Machine shutdown */
417 #ifdef CONFIG_LEDS_TRIGGER_CPU
418 extern void ledtrig_cpu(enum cpu_led_event evt);
420 static inline void ledtrig_cpu(enum cpu_led_event evt)
426 #endif /* __LINUX_LEDS_H_INCLUDED */