1 /* SPDX-License-Identifier: GPL-2.0-only */
3 * Driver model for leds and led triggers
5 * Copyright (C) 2005 John Lenz <lenz@cs.wisc.edu>
6 * Copyright (C) 2005 Richard Purdie <rpurdie@openedhand.com>
8 #ifndef __LINUX_LEDS_H_INCLUDED
9 #define __LINUX_LEDS_H_INCLUDED
11 #include <dt-bindings/leds/common.h>
12 #include <linux/device.h>
13 #include <linux/mutex.h>
14 #include <linux/rwsem.h>
15 #include <linux/spinlock.h>
16 #include <linux/timer.h>
17 #include <linux/types.h>
18 #include <linux/workqueue.h>
20 struct attribute_group;
26 struct platform_device;
32 /* This is obsolete/useless. We now support variable maximum brightness. */
40 enum led_default_state {
41 LEDS_DEFSTATE_OFF = 0,
43 LEDS_DEFSTATE_KEEP = 2,
47 * struct led_lookup_data - represents a single LED lookup entry
49 * @list: internal list of all LED lookup entries
50 * @provider: name of led_classdev providing the LED
51 * @dev_id: name of the device associated with this LED
52 * @con_id: name of the LED from the device's point of view
54 struct led_lookup_data {
55 struct list_head list;
61 struct led_init_data {
62 /* device fwnode handle */
63 struct fwnode_handle *fwnode;
65 * default <color:function> tuple, for backward compatibility
66 * with in-driver hard-coded LED names used as a fallback when
67 * DT "label" property is absent; it should be set to NULL
68 * in new LED class drivers.
70 const char *default_label;
72 * string to be used for devicename section of LED class device
73 * either for label based LED name composition path or for fwnode
74 * based when devname_mandatory is true
76 const char *devicename;
78 * indicates if LED name should always comprise devicename section;
79 * only LEDs exposed by drivers of hot-pluggable devices should
82 bool devname_mandatory;
85 #if IS_ENABLED(CONFIG_NEW_LEDS)
86 enum led_default_state led_init_default_state_get(struct fwnode_handle *fwnode);
88 static inline enum led_default_state
89 led_init_default_state_get(struct fwnode_handle *fwnode)
91 return LEDS_DEFSTATE_OFF;
95 struct led_hw_trigger_type {
101 unsigned int brightness;
102 unsigned int max_brightness;
106 /* Lower 16 bits reflect status */
107 #define LED_SUSPENDED BIT(0)
108 #define LED_UNREGISTERING BIT(1)
109 /* Upper 16 bits reflect control information */
110 #define LED_CORE_SUSPENDRESUME BIT(16)
111 #define LED_SYSFS_DISABLE BIT(17)
112 #define LED_DEV_CAP_FLASH BIT(18)
113 #define LED_HW_PLUGGABLE BIT(19)
114 #define LED_PANIC_INDICATOR BIT(20)
115 #define LED_BRIGHT_HW_CHANGED BIT(21)
116 #define LED_RETAIN_AT_SHUTDOWN BIT(22)
117 #define LED_INIT_DEFAULT_TRIGGER BIT(23)
119 /* set_brightness_work / blink_timer flags, atomic, private. */
120 unsigned long work_flags;
122 #define LED_BLINK_SW 0
123 #define LED_BLINK_ONESHOT 1
124 #define LED_BLINK_ONESHOT_STOP 2
125 #define LED_BLINK_INVERT 3
126 #define LED_BLINK_BRIGHTNESS_CHANGE 4
127 #define LED_BLINK_DISABLE 5
128 /* Brightness off also disables hw-blinking so it is a separate action */
129 #define LED_SET_BRIGHTNESS_OFF 6
130 #define LED_SET_BRIGHTNESS 7
131 #define LED_SET_BLINK 8
133 /* Set LED brightness level
134 * Must not sleep. Use brightness_set_blocking for drivers
135 * that can sleep while setting brightness.
137 void (*brightness_set)(struct led_classdev *led_cdev,
138 enum led_brightness brightness);
140 * Set LED brightness level immediately - it can block the caller for
141 * the time required for accessing a LED device register.
143 int (*brightness_set_blocking)(struct led_classdev *led_cdev,
144 enum led_brightness brightness);
145 /* Get LED brightness level */
146 enum led_brightness (*brightness_get)(struct led_classdev *led_cdev);
149 * Activate hardware accelerated blink, delays are in milliseconds
150 * and if both are zero then a sensible default should be chosen.
151 * The call should adjust the timings in that case and if it can't
152 * match the values specified exactly.
153 * Deactivate blinking again when the brightness is set to LED_OFF
154 * via the brightness_set() callback.
155 * For led_blink_set_nosleep() the LED core assumes that blink_set
156 * implementations, of drivers which do not use brightness_set_blocking,
157 * will not sleep. Therefor if brightness_set_blocking is not set
158 * this function must not sleep!
160 int (*blink_set)(struct led_classdev *led_cdev,
161 unsigned long *delay_on,
162 unsigned long *delay_off);
164 int (*pattern_set)(struct led_classdev *led_cdev,
165 struct led_pattern *pattern, u32 len, int repeat);
166 int (*pattern_clear)(struct led_classdev *led_cdev);
169 const struct attribute_group **groups;
171 struct list_head node; /* LED Device list */
172 const char *default_trigger; /* Trigger to use */
174 unsigned long blink_delay_on, blink_delay_off;
175 struct timer_list blink_timer;
176 int blink_brightness;
177 int new_blink_brightness;
178 void (*flash_resume)(struct led_classdev *led_cdev);
180 struct work_struct set_brightness_work;
181 int delayed_set_value;
182 unsigned long delayed_delay_on;
183 unsigned long delayed_delay_off;
185 #ifdef CONFIG_LEDS_TRIGGERS
186 /* Protects the trigger data below */
187 struct rw_semaphore trigger_lock;
189 struct led_trigger *trigger;
190 struct list_head trig_list;
192 /* true if activated - deactivate routine uses it to do cleanup */
195 /* LEDs that have private triggers have this set */
196 struct led_hw_trigger_type *trigger_type;
198 /* Unique trigger name supported by LED set in hw control mode */
199 const char *hw_control_trigger;
201 * Check if the LED driver supports the requested mode provided by the
202 * defined supported trigger to setup the LED to hw control mode.
204 * Return 0 on success. Return -EOPNOTSUPP when the passed flags are not
205 * supported and software fallback needs to be used.
206 * Return a negative error number on any other case for check fail due
207 * to various reason like device not ready or timeouts.
209 int (*hw_control_is_supported)(struct led_classdev *led_cdev,
210 unsigned long flags);
212 * Activate hardware control, LED driver will use the provided flags
213 * from the supported trigger and setup the LED to be driven by hardware
214 * following the requested mode from the trigger flags.
215 * Deactivate hardware blink control by setting brightness to LED_OFF via
216 * the brightness_set() callback.
218 * Return 0 on success, a negative error number on flags apply fail.
220 int (*hw_control_set)(struct led_classdev *led_cdev,
221 unsigned long flags);
223 * Get from the LED driver the current mode that the LED is set in hw
224 * control mode and put them in flags.
225 * Trigger can use this to get the initial state of a LED already set in
226 * hardware blink control.
228 * Return 0 on success, a negative error number on failing parsing the
229 * initial mode. Error from this function is NOT FATAL as the device
230 * may be in a not supported initial state by the attached LED trigger.
232 int (*hw_control_get)(struct led_classdev *led_cdev,
233 unsigned long *flags);
235 * Get the device this LED blinks in response to.
236 * e.g. for a PHY LED, it is the network device. If the LED is
237 * not yet associated to a device, return NULL.
239 struct device *(*hw_control_get_device)(struct led_classdev *led_cdev);
242 #ifdef CONFIG_LEDS_BRIGHTNESS_HW_CHANGED
243 int brightness_hw_changed;
244 struct kernfs_node *brightness_hw_changed_kn;
247 /* Ensures consistent access to the LED Flash Class device */
248 struct mutex led_access;
252 * led_classdev_register_ext - register a new object of LED class with
254 * @parent: LED controller device this LED is driven by
255 * @led_cdev: the led_classdev structure for this device
256 * @init_data: the LED class device initialization data
258 * Register a new object of LED class, with name derived from init_data.
260 * Returns: 0 on success or negative error value on failure
262 int led_classdev_register_ext(struct device *parent,
263 struct led_classdev *led_cdev,
264 struct led_init_data *init_data);
267 * led_classdev_register - register a new object of LED class
268 * @parent: LED controller device this LED is driven by
269 * @led_cdev: the led_classdev structure for this device
271 * Register a new object of LED class, with name derived from the name property
272 * of passed led_cdev argument.
274 * Returns: 0 on success or negative error value on failure
276 static inline int led_classdev_register(struct device *parent,
277 struct led_classdev *led_cdev)
279 return led_classdev_register_ext(parent, led_cdev, NULL);
282 #if IS_ENABLED(CONFIG_LEDS_CLASS)
283 int devm_led_classdev_register_ext(struct device *parent,
284 struct led_classdev *led_cdev,
285 struct led_init_data *init_data);
288 devm_led_classdev_register_ext(struct device *parent,
289 struct led_classdev *led_cdev,
290 struct led_init_data *init_data)
296 static inline int devm_led_classdev_register(struct device *parent,
297 struct led_classdev *led_cdev)
299 return devm_led_classdev_register_ext(parent, led_cdev, NULL);
301 void led_classdev_unregister(struct led_classdev *led_cdev);
302 void devm_led_classdev_unregister(struct device *parent,
303 struct led_classdev *led_cdev);
304 void led_classdev_suspend(struct led_classdev *led_cdev);
305 void led_classdev_resume(struct led_classdev *led_cdev);
307 void led_add_lookup(struct led_lookup_data *led_lookup);
308 void led_remove_lookup(struct led_lookup_data *led_lookup);
310 struct led_classdev *__must_check led_get(struct device *dev, char *con_id);
311 struct led_classdev *__must_check devm_led_get(struct device *dev, char *con_id);
313 extern struct led_classdev *of_led_get(struct device_node *np, int index);
314 extern void led_put(struct led_classdev *led_cdev);
315 struct led_classdev *__must_check devm_of_led_get(struct device *dev,
317 struct led_classdev *__must_check devm_of_led_get_optional(struct device *dev,
321 * led_blink_set - set blinking with software fallback
322 * @led_cdev: the LED to start blinking
323 * @delay_on: the time it should be on (in ms)
324 * @delay_off: the time it should ble off (in ms)
326 * This function makes the LED blink, attempting to use the
327 * hardware acceleration if possible, but falling back to
328 * software blinking if there is no hardware blinking or if
329 * the LED refuses the passed values.
331 * This function may sleep!
333 * Note that if software blinking is active, simply calling
334 * led_cdev->brightness_set() will not stop the blinking,
335 * use led_set_brightness() instead.
337 void led_blink_set(struct led_classdev *led_cdev, unsigned long *delay_on,
338 unsigned long *delay_off);
341 * led_blink_set_nosleep - set blinking, guaranteed to not sleep
342 * @led_cdev: the LED to start blinking
343 * @delay_on: the time it should be on (in ms)
344 * @delay_off: the time it should ble off (in ms)
346 * This function makes the LED blink and is guaranteed to not sleep. Otherwise
347 * this is the same as led_blink_set(), see led_blink_set() for details.
349 void led_blink_set_nosleep(struct led_classdev *led_cdev, unsigned long delay_on,
350 unsigned long delay_off);
353 * led_blink_set_oneshot - do a oneshot software blink
354 * @led_cdev: the LED to start blinking
355 * @delay_on: the time it should be on (in ms)
356 * @delay_off: the time it should ble off (in ms)
357 * @invert: blink off, then on, leaving the led on
359 * This function makes the LED blink one time for delay_on +
360 * delay_off time, ignoring the request if another one-shot
361 * blink is already in progress.
363 * If invert is set, led blinks for delay_off first, then for
364 * delay_on and leave the led on after the on-off cycle.
366 * This function is guaranteed not to sleep.
368 void led_blink_set_oneshot(struct led_classdev *led_cdev,
369 unsigned long *delay_on, unsigned long *delay_off,
372 * led_set_brightness - set LED brightness
373 * @led_cdev: the LED to set
374 * @brightness: the brightness to set it to
376 * Set an LED's brightness, and, if necessary, cancel the
377 * software blink timer that implements blinking when the
378 * hardware doesn't. This function is guaranteed not to sleep.
380 void led_set_brightness(struct led_classdev *led_cdev, unsigned int brightness);
383 * led_set_brightness_sync - set LED brightness synchronously
384 * @led_cdev: the LED to set
385 * @value: the brightness to set it to
387 * Set an LED's brightness immediately. This function will block
388 * the caller for the time required for accessing device registers,
391 * Returns: 0 on success or negative error value on failure
393 int led_set_brightness_sync(struct led_classdev *led_cdev, unsigned int value);
396 * led_update_brightness - update LED brightness
397 * @led_cdev: the LED to query
399 * Get an LED's current brightness and update led_cdev->brightness
400 * member with the obtained value.
402 * Returns: 0 on success or negative error value on failure
404 int led_update_brightness(struct led_classdev *led_cdev);
407 * led_get_default_pattern - return default pattern
409 * @led_cdev: the LED to get default pattern for
410 * @size: pointer for storing the number of elements in returned array,
411 * modified only if return != NULL
413 * Return: Allocated array of integers with default pattern from device tree
414 * or NULL. Caller is responsible for kfree().
416 u32 *led_get_default_pattern(struct led_classdev *led_cdev, unsigned int *size);
419 * led_sysfs_disable - disable LED sysfs interface
420 * @led_cdev: the LED to set
422 * Disable the led_cdev's sysfs interface.
424 void led_sysfs_disable(struct led_classdev *led_cdev);
427 * led_sysfs_enable - enable LED sysfs interface
428 * @led_cdev: the LED to set
430 * Enable the led_cdev's sysfs interface.
432 void led_sysfs_enable(struct led_classdev *led_cdev);
435 * led_compose_name - compose LED class device name
436 * @dev: LED controller device object
437 * @init_data: the LED class device initialization data
438 * @led_classdev_name: composed LED class device name
440 * Create LED class device name basing on the provided init_data argument.
441 * The name can have <devicename:color:function> or <color:function>.
442 * form, depending on the init_data configuration.
444 * Returns: 0 on success or negative error value on failure
446 int led_compose_name(struct device *dev, struct led_init_data *init_data,
447 char *led_classdev_name);
450 * led_sysfs_is_disabled - check if LED sysfs interface is disabled
451 * @led_cdev: the LED to query
453 * Returns: true if the led_cdev's sysfs interface is disabled.
455 static inline bool led_sysfs_is_disabled(struct led_classdev *led_cdev)
457 return led_cdev->flags & LED_SYSFS_DISABLE;
463 /* Registration functions for simple triggers */
464 #define DEFINE_LED_TRIGGER(x) static struct led_trigger *x;
465 #define DEFINE_LED_TRIGGER_GLOBAL(x) struct led_trigger *x;
467 #ifdef CONFIG_LEDS_TRIGGERS
469 #define TRIG_NAME_MAX 50
472 /* Trigger Properties */
474 int (*activate)(struct led_classdev *led_cdev);
475 void (*deactivate)(struct led_classdev *led_cdev);
477 /* LED-private triggers have this set */
478 struct led_hw_trigger_type *trigger_type;
480 /* LEDs under control by this trigger (for simple triggers) */
481 spinlock_t leddev_list_lock;
482 struct list_head led_cdevs;
484 /* Link to next registered trigger */
485 struct list_head next_trig;
487 const struct attribute_group **groups;
491 * Currently the attributes in struct led_trigger::groups are added directly to
492 * the LED device. As this might change in the future, the following
493 * macros abstract getting the LED device and its trigger_data from the dev
494 * parameter passed to the attribute accessor functions.
496 #define led_trigger_get_led(dev) ((struct led_classdev *)dev_get_drvdata((dev)))
497 #define led_trigger_get_drvdata(dev) (led_get_trigger_data(led_trigger_get_led(dev)))
499 /* Registration functions for complex triggers */
500 int led_trigger_register(struct led_trigger *trigger);
501 void led_trigger_unregister(struct led_trigger *trigger);
502 int devm_led_trigger_register(struct device *dev,
503 struct led_trigger *trigger);
505 void led_trigger_register_simple(const char *name,
506 struct led_trigger **trigger);
507 void led_trigger_unregister_simple(struct led_trigger *trigger);
508 void led_trigger_event(struct led_trigger *trigger, enum led_brightness event);
509 void led_trigger_blink(struct led_trigger *trigger, unsigned long delay_on,
510 unsigned long delay_off);
511 void led_trigger_blink_oneshot(struct led_trigger *trigger,
512 unsigned long delay_on,
513 unsigned long delay_off,
515 void led_trigger_set_default(struct led_classdev *led_cdev);
516 int led_trigger_set(struct led_classdev *led_cdev, struct led_trigger *trigger);
517 void led_trigger_remove(struct led_classdev *led_cdev);
519 static inline void led_set_trigger_data(struct led_classdev *led_cdev,
522 led_cdev->trigger_data = trigger_data;
525 static inline void *led_get_trigger_data(struct led_classdev *led_cdev)
527 return led_cdev->trigger_data;
531 * led_trigger_rename_static - rename a trigger
532 * @name: the new trigger name
533 * @trig: the LED trigger to rename
535 * Change a LED trigger name by copying the string passed in
536 * name into current trigger name, which MUST be large
537 * enough for the new string.
539 * Note that name must NOT point to the same string used
540 * during LED registration, as that could lead to races.
542 * This is meant to be used on triggers with statically
545 void led_trigger_rename_static(const char *name, struct led_trigger *trig);
547 #define module_led_trigger(__led_trigger) \
548 module_driver(__led_trigger, led_trigger_register, \
549 led_trigger_unregister)
553 /* Trigger has no members */
554 struct led_trigger {};
556 /* Trigger inline empty functions */
557 static inline void led_trigger_register_simple(const char *name,
558 struct led_trigger **trigger) {}
559 static inline void led_trigger_unregister_simple(struct led_trigger *trigger) {}
560 static inline void led_trigger_event(struct led_trigger *trigger,
561 enum led_brightness event) {}
562 static inline void led_trigger_blink(struct led_trigger *trigger,
563 unsigned long delay_on,
564 unsigned long delay_off) {}
565 static inline void led_trigger_blink_oneshot(struct led_trigger *trigger,
566 unsigned long delay_on,
567 unsigned long delay_off,
569 static inline void led_trigger_set_default(struct led_classdev *led_cdev) {}
570 static inline int led_trigger_set(struct led_classdev *led_cdev,
571 struct led_trigger *trigger)
576 static inline void led_trigger_remove(struct led_classdev *led_cdev) {}
577 static inline void led_set_trigger_data(struct led_classdev *led_cdev) {}
578 static inline void *led_get_trigger_data(struct led_classdev *led_cdev)
583 #endif /* CONFIG_LEDS_TRIGGERS */
585 /* Trigger specific enum */
586 enum led_trigger_netdev_modes {
587 TRIGGER_NETDEV_LINK = 0,
588 TRIGGER_NETDEV_LINK_10,
589 TRIGGER_NETDEV_LINK_100,
590 TRIGGER_NETDEV_LINK_1000,
591 TRIGGER_NETDEV_HALF_DUPLEX,
592 TRIGGER_NETDEV_FULL_DUPLEX,
597 __TRIGGER_NETDEV_MAX,
600 /* Trigger specific functions */
601 #ifdef CONFIG_LEDS_TRIGGER_DISK
602 void ledtrig_disk_activity(bool write);
604 static inline void ledtrig_disk_activity(bool write) {}
607 #ifdef CONFIG_LEDS_TRIGGER_MTD
608 void ledtrig_mtd_activity(void);
610 static inline void ledtrig_mtd_activity(void) {}
613 #if defined(CONFIG_LEDS_TRIGGER_CAMERA) || defined(CONFIG_LEDS_TRIGGER_CAMERA_MODULE)
614 void ledtrig_flash_ctrl(bool on);
615 void ledtrig_torch_ctrl(bool on);
617 static inline void ledtrig_flash_ctrl(bool on) {}
618 static inline void ledtrig_torch_ctrl(bool on) {}
622 * Generic LED platform data for describing LED names and default triggers.
626 const char *default_trigger;
630 struct led_platform_data {
632 struct led_info *leds;
635 struct led_properties {
638 const char *function;
640 bool func_enum_present;
644 typedef int (*gpio_blink_set_t)(struct gpio_desc *desc, int state,
645 unsigned long *delay_on,
646 unsigned long *delay_off);
648 /* For the leds-gpio driver */
651 const char *default_trigger;
653 unsigned active_low : 1;
654 unsigned retain_state_suspended : 1;
655 unsigned panic_indicator : 1;
656 unsigned default_state : 2;
657 unsigned retain_state_shutdown : 1;
658 /* default_state should be one of LEDS_GPIO_DEFSTATE_(ON|OFF|KEEP) */
659 struct gpio_desc *gpiod;
661 #define LEDS_GPIO_DEFSTATE_OFF LEDS_DEFSTATE_OFF
662 #define LEDS_GPIO_DEFSTATE_ON LEDS_DEFSTATE_ON
663 #define LEDS_GPIO_DEFSTATE_KEEP LEDS_DEFSTATE_KEEP
665 struct gpio_led_platform_data {
667 const struct gpio_led *leds;
669 #define GPIO_LED_NO_BLINK_LOW 0 /* No blink GPIO state low */
670 #define GPIO_LED_NO_BLINK_HIGH 1 /* No blink GPIO state high */
671 #define GPIO_LED_BLINK 2 /* Please, blink */
672 gpio_blink_set_t gpio_blink_set;
675 #ifdef CONFIG_NEW_LEDS
676 struct platform_device *gpio_led_register_device(
677 int id, const struct gpio_led_platform_data *pdata);
679 static inline struct platform_device *gpio_led_register_device(
680 int id, const struct gpio_led_platform_data *pdata)
687 CPU_LED_IDLE_START, /* CPU enters idle */
688 CPU_LED_IDLE_END, /* CPU idle ends */
689 CPU_LED_START, /* Machine starts, especially resume */
690 CPU_LED_STOP, /* Machine stops, especially suspend */
691 CPU_LED_HALTED, /* Machine shutdown */
693 #ifdef CONFIG_LEDS_TRIGGER_CPU
694 void ledtrig_cpu(enum cpu_led_event evt);
696 static inline void ledtrig_cpu(enum cpu_led_event evt)
702 #ifdef CONFIG_LEDS_BRIGHTNESS_HW_CHANGED
703 void led_classdev_notify_brightness_hw_changed(
704 struct led_classdev *led_cdev, unsigned int brightness);
706 static inline void led_classdev_notify_brightness_hw_changed(
707 struct led_classdev *led_cdev, enum led_brightness brightness) { }
711 * struct led_pattern - pattern interval settings
712 * @delta_t: pattern interval delay, in milliseconds
713 * @brightness: pattern interval brightness
721 LED_AUDIO_MUTE, /* master mute LED */
722 LED_AUDIO_MICMUTE, /* mic mute LED */
726 #if IS_ENABLED(CONFIG_LEDS_TRIGGER_AUDIO)
727 enum led_brightness ledtrig_audio_get(enum led_audio type);
728 void ledtrig_audio_set(enum led_audio type, enum led_brightness state);
730 static inline enum led_brightness ledtrig_audio_get(enum led_audio type)
734 static inline void ledtrig_audio_set(enum led_audio type,
735 enum led_brightness state)
740 #endif /* __LINUX_LEDS_H_INCLUDED */