1 /* SPDX-License-Identifier: GPL-2.0-only */
3 * Driver model for leds and led triggers
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32 /* This is obsolete/useless.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;
105 /* Lower 16 bits reflect status */
106 #define LED_SUSPENDED BIT(0)
107 #define LED_UNREGISTERING BIT(1)
108 /* Upper 16 bits reflect control information */
109 #define LED_CORE_SUSPENDRESUME BIT(16)
110 #define LED_SYSFS_DISABLE BIT(17)
111 #define LED_DEV_CAP_FLASH BIT(18)
112 #define LED_HW_PLUGGABLE BIT(19)
113 #define LED_PANIC_INDICATOR BIT(20)
114 #define LED_BRIGHT_HW_CHANGED BIT(21)
115 #define LED_RETAIN_AT_SHUTDOWN BIT(22)
116 #define LED_INIT_DEFAULT_TRIGGER BIT(23)
118 /* set_brightness_work / blink_timer flags, atomic, private. */
119 unsigned long work_flags;
121 #define LED_BLINK_SW 0
122 #define LED_BLINK_ONESHOT 1
123 #define LED_BLINK_ONESHOT_STOP 2
124 #define LED_BLINK_INVERT 3
125 #define LED_BLINK_BRIGHTNESS_CHANGE 4
126 #define LED_BLINK_DISABLE 5
127 /* Brightness off also disables hw-blinking so it is a separate action */
128 #define LED_SET_BRIGHTNESS_OFF 6
129 #define LED_SET_BRIGHTNESS 7
130 #define LED_SET_BLINK 8
132 /* Set LED brightness level
133 * Must not sleep. Use brightness_set_blocking for drivers
134 * that can sleep while setting brightness.
136 void (*brightness_set)(struct led_classdev *led_cdev,
137 enum led_brightness brightness);
139 * Set LED brightness level immediately - it can block the caller for
140 * the time required for accessing a LED device register.
142 int (*brightness_set_blocking)(struct led_classdev *led_cdev,
143 enum led_brightness brightness);
144 /* Get LED brightness level */
145 enum led_brightness (*brightness_get)(struct led_classdev *led_cdev);
148 * Activate hardware accelerated blink, delays are in milliseconds
149 * and if both are zero then a sensible default should be chosen.
150 * The call should adjust the timings in that case and if it can't
151 * match the values specified exactly.
152 * Deactivate blinking again when the brightness is set to LED_OFF
153 * via the brightness_set() callback.
154 * For led_blink_set_nosleep() the LED core assumes that blink_set
155 * implementations, of drivers which do not use brightness_set_blocking,
156 * will not sleep. Therefor if brightness_set_blocking is not set
157 * this function must not sleep!
159 int (*blink_set)(struct led_classdev *led_cdev,
160 unsigned long *delay_on,
161 unsigned long *delay_off);
163 int (*pattern_set)(struct led_classdev *led_cdev,
164 struct led_pattern *pattern, u32 len, int repeat);
165 int (*pattern_clear)(struct led_classdev *led_cdev);
168 const struct attribute_group **groups;
170 struct list_head node; /* LED Device list */
171 const char *default_trigger; /* Trigger to use */
173 unsigned long blink_delay_on, blink_delay_off;
174 struct timer_list blink_timer;
175 int blink_brightness;
176 int new_blink_brightness;
177 void (*flash_resume)(struct led_classdev *led_cdev);
179 struct work_struct set_brightness_work;
180 int delayed_set_value;
181 unsigned long delayed_delay_on;
182 unsigned long delayed_delay_off;
184 #ifdef CONFIG_LEDS_TRIGGERS
185 /* Protects the trigger data below */
186 struct rw_semaphore trigger_lock;
188 struct led_trigger *trigger;
189 struct list_head trig_list;
191 /* true if activated - deactivate routine uses it to do cleanup */
194 /* LEDs that have private triggers have this set */
195 struct led_hw_trigger_type *trigger_type;
197 /* Unique trigger name supported by LED set in hw control mode */
198 const char *hw_control_trigger;
200 * Check if the LED driver supports the requested mode provided by the
201 * defined supported trigger to setup the LED to hw control mode.
203 * Return 0 on success. Return -EOPNOTSUPP when the passed flags are not
204 * supported and software fallback needs to be used.
205 * Return a negative error number on any other case for check fail due
206 * to various reason like device not ready or timeouts.
208 int (*hw_control_is_supported)(struct led_classdev *led_cdev,
209 unsigned long flags);
211 * Activate hardware control, LED driver will use the provided flags
212 * from the supported trigger and setup the LED to be driven by hardware
213 * following the requested mode from the trigger flags.
214 * Deactivate hardware blink control by setting brightness to LED_OFF via
215 * the brightness_set() callback.
217 * Return 0 on success, a negative error number on flags apply fail.
219 int (*hw_control_set)(struct led_classdev *led_cdev,
220 unsigned long flags);
222 * Get from the LED driver the current mode that the LED is set in hw
223 * control mode and put them in flags.
224 * Trigger can use this to get the initial state of a LED already set in
225 * hardware blink control.
227 * Return 0 on success, a negative error number on failing parsing the
228 * initial mode. Error from this function is NOT FATAL as the device
229 * may be in a not supported initial state by the attached LED trigger.
231 int (*hw_control_get)(struct led_classdev *led_cdev,
232 unsigned long *flags);
234 * Get the device this LED blinks in response to.
235 * e.g. for a PHY LED, it is the network device. If the LED is
236 * not yet associated to a device, return NULL.
238 struct device *(*hw_control_get_device)(struct led_classdev *led_cdev);
241 #ifdef CONFIG_LEDS_BRIGHTNESS_HW_CHANGED
242 int brightness_hw_changed;
243 struct kernfs_node *brightness_hw_changed_kn;
246 /* Ensures consistent access to the LED Flash Class device */
247 struct mutex led_access;
251 * led_classdev_register_ext - register a new object of LED class with
253 * @parent: LED controller device this LED is driven by
254 * @led_cdev: the led_classdev structure for this device
255 * @init_data: the LED class device initialization data
257 * Register a new object of LED class, with name derived from init_data.
259 * Returns: 0 on success or negative error value on failure
261 int led_classdev_register_ext(struct device *parent,
262 struct led_classdev *led_cdev,
263 struct led_init_data *init_data);
266 * led_classdev_register - register a new object of LED class
267 * @parent: LED controller device this LED is driven by
268 * @led_cdev: the led_classdev structure for this device
270 * Register a new object of LED class, with name derived from the name property
271 * of passed led_cdev argument.
273 * Returns: 0 on success or negative error value on failure
275 static inline int led_classdev_register(struct device *parent,
276 struct led_classdev *led_cdev)
278 return led_classdev_register_ext(parent, led_cdev, NULL);
281 #if IS_ENABLED(CONFIG_LEDS_CLASS)
282 int devm_led_classdev_register_ext(struct device *parent,
283 struct led_classdev *led_cdev,
284 struct led_init_data *init_data);
287 devm_led_classdev_register_ext(struct device *parent,
288 struct led_classdev *led_cdev,
289 struct led_init_data *init_data)
295 static inline int devm_led_classdev_register(struct device *parent,
296 struct led_classdev *led_cdev)
298 return devm_led_classdev_register_ext(parent, led_cdev, NULL);
300 void led_classdev_unregister(struct led_classdev *led_cdev);
301 void devm_led_classdev_unregister(struct device *parent,
302 struct led_classdev *led_cdev);
303 void led_classdev_suspend(struct led_classdev *led_cdev);
304 void led_classdev_resume(struct led_classdev *led_cdev);
306 void led_add_lookup(struct led_lookup_data *led_lookup);
307 void led_remove_lookup(struct led_lookup_data *led_lookup);
309 struct led_classdev *__must_check led_get(struct device *dev, char *con_id);
310 struct led_classdev *__must_check devm_led_get(struct device *dev, char *con_id);
312 extern struct led_classdev *of_led_get(struct device_node *np, int index);
313 extern void led_put(struct led_classdev *led_cdev);
314 struct led_classdev *__must_check devm_of_led_get(struct device *dev,
318 * led_blink_set - set blinking with software fallback
319 * @led_cdev: the LED to start blinking
320 * @delay_on: the time it should be on (in ms)
321 * @delay_off: the time it should ble off (in ms)
323 * This function makes the LED blink, attempting to use the
324 * hardware acceleration if possible, but falling back to
325 * software blinking if there is no hardware blinking or if
326 * the LED refuses the passed values.
328 * This function may sleep!
330 * Note that if software blinking is active, simply calling
331 * led_cdev->brightness_set() will not stop the blinking,
332 * use led_set_brightness() instead.
334 void led_blink_set(struct led_classdev *led_cdev, unsigned long *delay_on,
335 unsigned long *delay_off);
338 * led_blink_set_nosleep - set blinking, guaranteed to not sleep
339 * @led_cdev: the LED to start blinking
340 * @delay_on: the time it should be on (in ms)
341 * @delay_off: the time it should ble off (in ms)
343 * This function makes the LED blink and is guaranteed to not sleep. Otherwise
344 * this is the same as led_blink_set(), see led_blink_set() for details.
346 void led_blink_set_nosleep(struct led_classdev *led_cdev, unsigned long delay_on,
347 unsigned long delay_off);
350 * led_blink_set_oneshot - do a oneshot software blink
351 * @led_cdev: the LED to start blinking
352 * @delay_on: the time it should be on (in ms)
353 * @delay_off: the time it should ble off (in ms)
354 * @invert: blink off, then on, leaving the led on
356 * This function makes the LED blink one time for delay_on +
357 * delay_off time, ignoring the request if another one-shot
358 * blink is already in progress.
360 * If invert is set, led blinks for delay_off first, then for
361 * delay_on and leave the led on after the on-off cycle.
363 * This function is guaranteed not to sleep.
365 void led_blink_set_oneshot(struct led_classdev *led_cdev,
366 unsigned long *delay_on, unsigned long *delay_off,
369 * led_set_brightness - set LED brightness
370 * @led_cdev: the LED to set
371 * @brightness: the brightness to set it to
373 * Set an LED's brightness, and, if necessary, cancel the
374 * software blink timer that implements blinking when the
375 * hardware doesn't. This function is guaranteed not to sleep.
377 void led_set_brightness(struct led_classdev *led_cdev, unsigned int brightness);
380 * led_set_brightness_sync - set LED brightness synchronously
381 * @led_cdev: the LED to set
382 * @value: the brightness to set it to
384 * Set an LED's brightness immediately. This function will block
385 * the caller for the time required for accessing device registers,
388 * Returns: 0 on success or negative error value on failure
390 int led_set_brightness_sync(struct led_classdev *led_cdev, unsigned int value);
393 * led_update_brightness - update LED brightness
394 * @led_cdev: the LED to query
396 * Get an LED's current brightness and update led_cdev->brightness
397 * member with the obtained value.
399 * Returns: 0 on success or negative error value on failure
401 int led_update_brightness(struct led_classdev *led_cdev);
404 * led_get_default_pattern - return default pattern
406 * @led_cdev: the LED to get default pattern for
407 * @size: pointer for storing the number of elements in returned array,
408 * modified only if return != NULL
410 * Return: Allocated array of integers with default pattern from device tree
411 * or NULL. Caller is responsible for kfree().
413 u32 *led_get_default_pattern(struct led_classdev *led_cdev, unsigned int *size);
416 * led_sysfs_disable - disable LED sysfs interface
417 * @led_cdev: the LED to set
419 * Disable the led_cdev's sysfs interface.
421 void led_sysfs_disable(struct led_classdev *led_cdev);
424 * led_sysfs_enable - enable LED sysfs interface
425 * @led_cdev: the LED to set
427 * Enable the led_cdev's sysfs interface.
429 void led_sysfs_enable(struct led_classdev *led_cdev);
432 * led_compose_name - compose LED class device name
433 * @dev: LED controller device object
434 * @init_data: the LED class device initialization data
435 * @led_classdev_name: composed LED class device name
437 * Create LED class device name basing on the provided init_data argument.
438 * The name can have <devicename:color:function> or <color:function>.
439 * form, depending on the init_data configuration.
441 * Returns: 0 on success or negative error value on failure
443 int led_compose_name(struct device *dev, struct led_init_data *init_data,
444 char *led_classdev_name);
447 * led_sysfs_is_disabled - check if LED sysfs interface is disabled
448 * @led_cdev: the LED to query
450 * Returns: true if the led_cdev's sysfs interface is disabled.
452 static inline bool led_sysfs_is_disabled(struct led_classdev *led_cdev)
454 return led_cdev->flags & LED_SYSFS_DISABLE;
460 /* Registration functions for simple triggers */
461 #define DEFINE_LED_TRIGGER(x) static struct led_trigger *x;
462 #define DEFINE_LED_TRIGGER_GLOBAL(x) struct led_trigger *x;
464 #ifdef CONFIG_LEDS_TRIGGERS
466 #define TRIG_NAME_MAX 50
469 /* Trigger Properties */
471 int (*activate)(struct led_classdev *led_cdev);
472 void (*deactivate)(struct led_classdev *led_cdev);
474 /* LED-private triggers have this set */
475 struct led_hw_trigger_type *trigger_type;
477 /* LEDs under control by this trigger (for simple triggers) */
478 spinlock_t leddev_list_lock;
479 struct list_head led_cdevs;
481 /* Link to next registered trigger */
482 struct list_head next_trig;
484 const struct attribute_group **groups;
488 * Currently the attributes in struct led_trigger::groups are added directly to
489 * the LED device. As this might change in the future, the following
490 * macros abstract getting the LED device and its trigger_data from the dev
491 * parameter passed to the attribute accessor functions.
493 #define led_trigger_get_led(dev) ((struct led_classdev *)dev_get_drvdata((dev)))
494 #define led_trigger_get_drvdata(dev) (led_get_trigger_data(led_trigger_get_led(dev)))
496 /* Registration functions for complex triggers */
497 int led_trigger_register(struct led_trigger *trigger);
498 void led_trigger_unregister(struct led_trigger *trigger);
499 int devm_led_trigger_register(struct device *dev,
500 struct led_trigger *trigger);
502 void led_trigger_register_simple(const char *name,
503 struct led_trigger **trigger);
504 void led_trigger_unregister_simple(struct led_trigger *trigger);
505 void led_trigger_event(struct led_trigger *trigger, enum led_brightness event);
506 void led_trigger_blink(struct led_trigger *trigger, unsigned long delay_on,
507 unsigned long delay_off);
508 void led_trigger_blink_oneshot(struct led_trigger *trigger,
509 unsigned long delay_on,
510 unsigned long delay_off,
512 void led_trigger_set_default(struct led_classdev *led_cdev);
513 int led_trigger_set(struct led_classdev *led_cdev, struct led_trigger *trigger);
514 void led_trigger_remove(struct led_classdev *led_cdev);
516 static inline void led_set_trigger_data(struct led_classdev *led_cdev,
519 led_cdev->trigger_data = trigger_data;
522 static inline void *led_get_trigger_data(struct led_classdev *led_cdev)
524 return led_cdev->trigger_data;
528 * led_trigger_rename_static - rename a trigger
529 * @name: the new trigger name
530 * @trig: the LED trigger to rename
532 * Change a LED trigger name by copying the string passed in
533 * name into current trigger name, which MUST be large
534 * enough for the new string.
536 * Note that name must NOT point to the same string used
537 * during LED registration, as that could lead to races.
539 * This is meant to be used on triggers with statically
542 void led_trigger_rename_static(const char *name, struct led_trigger *trig);
544 #define module_led_trigger(__led_trigger) \
545 module_driver(__led_trigger, led_trigger_register, \
546 led_trigger_unregister)
550 /* Trigger has no members */
551 struct led_trigger {};
553 /* Trigger inline empty functions */
554 static inline void led_trigger_register_simple(const char *name,
555 struct led_trigger **trigger) {}
556 static inline void led_trigger_unregister_simple(struct led_trigger *trigger) {}
557 static inline void led_trigger_event(struct led_trigger *trigger,
558 enum led_brightness event) {}
559 static inline void led_trigger_blink(struct led_trigger *trigger,
560 unsigned long delay_on,
561 unsigned long delay_off) {}
562 static inline void led_trigger_blink_oneshot(struct led_trigger *trigger,
563 unsigned long delay_on,
564 unsigned long delay_off,
566 static inline void led_trigger_set_default(struct led_classdev *led_cdev) {}
567 static inline int led_trigger_set(struct led_classdev *led_cdev,
568 struct led_trigger *trigger)
573 static inline void led_trigger_remove(struct led_classdev *led_cdev) {}
574 static inline void led_set_trigger_data(struct led_classdev *led_cdev) {}
575 static inline void *led_get_trigger_data(struct led_classdev *led_cdev)
580 #endif /* CONFIG_LEDS_TRIGGERS */
582 /* Trigger specific enum */
583 enum led_trigger_netdev_modes {
584 TRIGGER_NETDEV_LINK = 0,
585 TRIGGER_NETDEV_LINK_10,
586 TRIGGER_NETDEV_LINK_100,
587 TRIGGER_NETDEV_LINK_1000,
588 TRIGGER_NETDEV_HALF_DUPLEX,
589 TRIGGER_NETDEV_FULL_DUPLEX,
594 __TRIGGER_NETDEV_MAX,
597 /* Trigger specific functions */
598 #ifdef CONFIG_LEDS_TRIGGER_DISK
599 void ledtrig_disk_activity(bool write);
601 static inline void ledtrig_disk_activity(bool write) {}
604 #ifdef CONFIG_LEDS_TRIGGER_MTD
605 void ledtrig_mtd_activity(void);
607 static inline void ledtrig_mtd_activity(void) {}
610 #if defined(CONFIG_LEDS_TRIGGER_CAMERA) || defined(CONFIG_LEDS_TRIGGER_CAMERA_MODULE)
611 void ledtrig_flash_ctrl(bool on);
612 void ledtrig_torch_ctrl(bool on);
614 static inline void ledtrig_flash_ctrl(bool on) {}
615 static inline void ledtrig_torch_ctrl(bool on) {}
619 * Generic LED platform data for describing LED names and default triggers.
623 const char *default_trigger;
627 struct led_platform_data {
629 struct led_info *leds;
632 struct led_properties {
635 const char *function;
637 bool func_enum_present;
641 typedef int (*gpio_blink_set_t)(struct gpio_desc *desc, int state,
642 unsigned long *delay_on,
643 unsigned long *delay_off);
645 /* For the leds-gpio driver */
648 const char *default_trigger;
650 unsigned active_low : 1;
651 unsigned retain_state_suspended : 1;
652 unsigned panic_indicator : 1;
653 unsigned default_state : 2;
654 unsigned retain_state_shutdown : 1;
655 /* default_state should be one of LEDS_GPIO_DEFSTATE_(ON|OFF|KEEP) */
656 struct gpio_desc *gpiod;
658 #define LEDS_GPIO_DEFSTATE_OFF LEDS_DEFSTATE_OFF
659 #define LEDS_GPIO_DEFSTATE_ON LEDS_DEFSTATE_ON
660 #define LEDS_GPIO_DEFSTATE_KEEP LEDS_DEFSTATE_KEEP
662 struct gpio_led_platform_data {
664 const struct gpio_led *leds;
666 #define GPIO_LED_NO_BLINK_LOW 0 /* No blink GPIO state low */
667 #define GPIO_LED_NO_BLINK_HIGH 1 /* No blink GPIO state high */
668 #define GPIO_LED_BLINK 2 /* Please, blink */
669 gpio_blink_set_t gpio_blink_set;
672 #ifdef CONFIG_NEW_LEDS
673 struct platform_device *gpio_led_register_device(
674 int id, const struct gpio_led_platform_data *pdata);
676 static inline struct platform_device *gpio_led_register_device(
677 int id, const struct gpio_led_platform_data *pdata)
684 CPU_LED_IDLE_START, /* CPU enters idle */
685 CPU_LED_IDLE_END, /* CPU idle ends */
686 CPU_LED_START, /* Machine starts, especially resume */
687 CPU_LED_STOP, /* Machine stops, especially suspend */
688 CPU_LED_HALTED, /* Machine shutdown */
690 #ifdef CONFIG_LEDS_TRIGGER_CPU
691 void ledtrig_cpu(enum cpu_led_event evt);
693 static inline void ledtrig_cpu(enum cpu_led_event evt)
699 #ifdef CONFIG_LEDS_BRIGHTNESS_HW_CHANGED
700 void led_classdev_notify_brightness_hw_changed(
701 struct led_classdev *led_cdev, unsigned int brightness);
703 static inline void led_classdev_notify_brightness_hw_changed(
704 struct led_classdev *led_cdev, enum led_brightness brightness) { }
708 * struct led_pattern - pattern interval settings
709 * @delta_t: pattern interval delay, in milliseconds
710 * @brightness: pattern interval brightness
718 LED_AUDIO_MUTE, /* master mute LED */
719 LED_AUDIO_MICMUTE, /* mic mute LED */
723 #if IS_ENABLED(CONFIG_LEDS_TRIGGER_AUDIO)
724 enum led_brightness ledtrig_audio_get(enum led_audio type);
725 void ledtrig_audio_set(enum led_audio type, enum led_brightness state);
727 static inline enum led_brightness ledtrig_audio_get(enum led_audio type)
731 static inline void ledtrig_audio_set(enum led_audio type,
732 enum led_brightness state)
737 #endif /* __LINUX_LEDS_H_INCLUDED */