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32 /* This is obsolete/useless.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 enum led_default_state led_init_default_state_get(struct fwnode_handle *fwnode);
87 struct led_hw_trigger_type {
93 unsigned int brightness;
94 unsigned int max_brightness;
98 /* Lower 16 bits reflect status */
99 #define LED_SUSPENDED BIT(0)
100 #define LED_UNREGISTERING BIT(1)
101 /* Upper 16 bits reflect control information */
102 #define LED_CORE_SUSPENDRESUME BIT(16)
103 #define LED_SYSFS_DISABLE BIT(17)
104 #define LED_DEV_CAP_FLASH BIT(18)
105 #define LED_HW_PLUGGABLE BIT(19)
106 #define LED_PANIC_INDICATOR BIT(20)
107 #define LED_BRIGHT_HW_CHANGED BIT(21)
108 #define LED_RETAIN_AT_SHUTDOWN BIT(22)
109 #define LED_INIT_DEFAULT_TRIGGER BIT(23)
110 #define LED_REJECT_NAME_CONFLICT BIT(24)
111 #define LED_MULTI_COLOR BIT(25)
113 /* set_brightness_work / blink_timer flags, atomic, private. */
114 unsigned long work_flags;
116 #define LED_BLINK_SW 0
117 #define LED_BLINK_ONESHOT 1
118 #define LED_BLINK_ONESHOT_STOP 2
119 #define LED_BLINK_INVERT 3
120 #define LED_BLINK_BRIGHTNESS_CHANGE 4
121 #define LED_BLINK_DISABLE 5
122 /* Brightness off also disables hw-blinking so it is a separate action */
123 #define LED_SET_BRIGHTNESS_OFF 6
124 #define LED_SET_BRIGHTNESS 7
125 #define LED_SET_BLINK 8
127 /* Set LED brightness level
128 * Must not sleep. Use brightness_set_blocking for drivers
129 * that can sleep while setting brightness.
131 void (*brightness_set)(struct led_classdev *led_cdev,
132 enum led_brightness brightness);
134 * Set LED brightness level immediately - it can block the caller for
135 * the time required for accessing a LED device register.
137 int (*brightness_set_blocking)(struct led_classdev *led_cdev,
138 enum led_brightness brightness);
139 /* Get LED brightness level */
140 enum led_brightness (*brightness_get)(struct led_classdev *led_cdev);
143 * Activate hardware accelerated blink, delays are in milliseconds
144 * and if both are zero then a sensible default should be chosen.
145 * The call should adjust the timings in that case and if it can't
146 * match the values specified exactly.
147 * Deactivate blinking again when the brightness is set to LED_OFF
148 * via the brightness_set() callback.
149 * For led_blink_set_nosleep() the LED core assumes that blink_set
150 * implementations, of drivers which do not use brightness_set_blocking,
151 * will not sleep. Therefor if brightness_set_blocking is not set
152 * this function must not sleep!
154 int (*blink_set)(struct led_classdev *led_cdev,
155 unsigned long *delay_on,
156 unsigned long *delay_off);
158 int (*pattern_set)(struct led_classdev *led_cdev,
159 struct led_pattern *pattern, u32 len, int repeat);
160 int (*pattern_clear)(struct led_classdev *led_cdev);
163 const struct attribute_group **groups;
165 struct list_head node; /* LED Device list */
166 const char *default_trigger; /* Trigger to use */
168 unsigned long blink_delay_on, blink_delay_off;
169 struct timer_list blink_timer;
170 int blink_brightness;
171 int new_blink_brightness;
172 void (*flash_resume)(struct led_classdev *led_cdev);
174 struct work_struct set_brightness_work;
175 int delayed_set_value;
176 unsigned long delayed_delay_on;
177 unsigned long delayed_delay_off;
179 #ifdef CONFIG_LEDS_TRIGGERS
180 /* Protects the trigger data below */
181 struct rw_semaphore trigger_lock;
183 struct led_trigger *trigger;
184 struct list_head trig_list;
186 /* true if activated - deactivate routine uses it to do cleanup */
189 /* LEDs that have private triggers have this set */
190 struct led_hw_trigger_type *trigger_type;
192 /* Unique trigger name supported by LED set in hw control mode */
193 const char *hw_control_trigger;
195 * Check if the LED driver supports the requested mode provided by the
196 * defined supported trigger to setup the LED to hw control mode.
198 * Return 0 on success. Return -EOPNOTSUPP when the passed flags are not
199 * supported and software fallback needs to be used.
200 * Return a negative error number on any other case for check fail due
201 * to various reason like device not ready or timeouts.
203 int (*hw_control_is_supported)(struct led_classdev *led_cdev,
204 unsigned long flags);
206 * Activate hardware control, LED driver will use the provided flags
207 * from the supported trigger and setup the LED to be driven by hardware
208 * following the requested mode from the trigger flags.
209 * Deactivate hardware blink control by setting brightness to LED_OFF via
210 * the brightness_set() callback.
212 * Return 0 on success, a negative error number on flags apply fail.
214 int (*hw_control_set)(struct led_classdev *led_cdev,
215 unsigned long flags);
217 * Get from the LED driver the current mode that the LED is set in hw
218 * control mode and put them in flags.
219 * Trigger can use this to get the initial state of a LED already set in
220 * hardware blink control.
222 * Return 0 on success, a negative error number on failing parsing the
223 * initial mode. Error from this function is NOT FATAL as the device
224 * may be in a not supported initial state by the attached LED trigger.
226 int (*hw_control_get)(struct led_classdev *led_cdev,
227 unsigned long *flags);
229 * Get the device this LED blinks in response to.
230 * e.g. for a PHY LED, it is the network device. If the LED is
231 * not yet associated to a device, return NULL.
233 struct device *(*hw_control_get_device)(struct led_classdev *led_cdev);
236 #ifdef CONFIG_LEDS_BRIGHTNESS_HW_CHANGED
237 int brightness_hw_changed;
238 struct kernfs_node *brightness_hw_changed_kn;
241 /* Ensures consistent access to the LED Flash Class device */
242 struct mutex led_access;
246 * led_classdev_register_ext - register a new object of LED class with
248 * @parent: LED controller device this LED is driven by
249 * @led_cdev: the led_classdev structure for this device
250 * @init_data: the LED class device initialization data
252 * Register a new object of LED class, with name derived from init_data.
254 * Returns: 0 on success or negative error value on failure
256 int led_classdev_register_ext(struct device *parent,
257 struct led_classdev *led_cdev,
258 struct led_init_data *init_data);
261 * led_classdev_register - register a new object of LED class
262 * @parent: LED controller device this LED is driven by
263 * @led_cdev: the led_classdev structure for this device
265 * Register a new object of LED class, with name derived from the name property
266 * of passed led_cdev argument.
268 * Returns: 0 on success or negative error value on failure
270 static inline int led_classdev_register(struct device *parent,
271 struct led_classdev *led_cdev)
273 return led_classdev_register_ext(parent, led_cdev, NULL);
276 int devm_led_classdev_register_ext(struct device *parent,
277 struct led_classdev *led_cdev,
278 struct led_init_data *init_data);
279 static inline int devm_led_classdev_register(struct device *parent,
280 struct led_classdev *led_cdev)
282 return devm_led_classdev_register_ext(parent, led_cdev, NULL);
284 void led_classdev_unregister(struct led_classdev *led_cdev);
285 void devm_led_classdev_unregister(struct device *parent,
286 struct led_classdev *led_cdev);
287 void led_classdev_suspend(struct led_classdev *led_cdev);
288 void led_classdev_resume(struct led_classdev *led_cdev);
290 void led_add_lookup(struct led_lookup_data *led_lookup);
291 void led_remove_lookup(struct led_lookup_data *led_lookup);
293 struct led_classdev *__must_check led_get(struct device *dev, char *con_id);
294 struct led_classdev *__must_check devm_led_get(struct device *dev, char *con_id);
296 extern struct led_classdev *of_led_get(struct device_node *np, int index);
297 extern void led_put(struct led_classdev *led_cdev);
298 struct led_classdev *__must_check devm_of_led_get(struct device *dev,
300 struct led_classdev *__must_check devm_of_led_get_optional(struct device *dev,
304 * led_blink_set - set blinking with software fallback
305 * @led_cdev: the LED to start blinking
306 * @delay_on: the time it should be on (in ms)
307 * @delay_off: the time it should ble off (in ms)
309 * This function makes the LED blink, attempting to use the
310 * hardware acceleration if possible, but falling back to
311 * software blinking if there is no hardware blinking or if
312 * the LED refuses the passed values.
314 * This function may sleep!
316 * Note that if software blinking is active, simply calling
317 * led_cdev->brightness_set() will not stop the blinking,
318 * use led_set_brightness() instead.
320 void led_blink_set(struct led_classdev *led_cdev, unsigned long *delay_on,
321 unsigned long *delay_off);
324 * led_blink_set_nosleep - set blinking, guaranteed to not sleep
325 * @led_cdev: the LED to start blinking
326 * @delay_on: the time it should be on (in ms)
327 * @delay_off: the time it should ble off (in ms)
329 * This function makes the LED blink and is guaranteed to not sleep. Otherwise
330 * this is the same as led_blink_set(), see led_blink_set() for details.
332 void led_blink_set_nosleep(struct led_classdev *led_cdev, unsigned long delay_on,
333 unsigned long delay_off);
336 * led_blink_set_oneshot - do a oneshot software blink
337 * @led_cdev: the LED to start blinking
338 * @delay_on: the time it should be on (in ms)
339 * @delay_off: the time it should ble off (in ms)
340 * @invert: blink off, then on, leaving the led on
342 * This function makes the LED blink one time for delay_on +
343 * delay_off time, ignoring the request if another one-shot
344 * blink is already in progress.
346 * If invert is set, led blinks for delay_off first, then for
347 * delay_on and leave the led on after the on-off cycle.
349 * This function is guaranteed not to sleep.
351 void led_blink_set_oneshot(struct led_classdev *led_cdev,
352 unsigned long *delay_on, unsigned long *delay_off,
355 * led_set_brightness - set LED brightness
356 * @led_cdev: the LED to set
357 * @brightness: the brightness to set it to
359 * Set an LED's brightness, and, if necessary, cancel the
360 * software blink timer that implements blinking when the
361 * hardware doesn't. This function is guaranteed not to sleep.
363 void led_set_brightness(struct led_classdev *led_cdev, unsigned int brightness);
366 * led_set_brightness_sync - set LED brightness synchronously
367 * @led_cdev: the LED to set
368 * @value: the brightness to set it to
370 * Set an LED's brightness immediately. This function will block
371 * the caller for the time required for accessing device registers,
374 * Returns: 0 on success or negative error value on failure
376 int led_set_brightness_sync(struct led_classdev *led_cdev, unsigned int value);
379 * led_mc_set_brightness - set mc LED color intensity values and brightness
380 * @led_cdev: the LED to set
381 * @intensity_value: array of per color intensity values to set
382 * @num_colors: amount of entries in intensity_value array
383 * @brightness: the brightness to set the LED to
385 * Set a multi-color LED's per color intensity values and brightness.
386 * If necessary, this cancels the software blink timer. This function is
387 * guaranteed not to sleep.
389 * Calling this function on a non multi-color led_classdev or with the wrong
390 * num_colors value is an error. In this case an error will be logged once
391 * and the call will do nothing.
393 void led_mc_set_brightness(struct led_classdev *led_cdev,
394 unsigned int *intensity_value, unsigned int num_colors,
395 unsigned int brightness);
398 * led_update_brightness - update LED brightness
399 * @led_cdev: the LED to query
401 * Get an LED's current brightness and update led_cdev->brightness
402 * member with the obtained value.
404 * Returns: 0 on success or negative error value on failure
406 int led_update_brightness(struct led_classdev *led_cdev);
409 * led_get_default_pattern - return default pattern
411 * @led_cdev: the LED to get default pattern for
412 * @size: pointer for storing the number of elements in returned array,
413 * modified only if return != NULL
415 * Return: Allocated array of integers with default pattern from device tree
416 * or NULL. Caller is responsible for kfree().
418 u32 *led_get_default_pattern(struct led_classdev *led_cdev, unsigned int *size);
421 * led_sysfs_disable - disable LED sysfs interface
422 * @led_cdev: the LED to set
424 * Disable the led_cdev's sysfs interface.
426 void led_sysfs_disable(struct led_classdev *led_cdev);
429 * led_sysfs_enable - enable LED sysfs interface
430 * @led_cdev: the LED to set
432 * Enable the led_cdev's sysfs interface.
434 void led_sysfs_enable(struct led_classdev *led_cdev);
437 * led_compose_name - compose LED class device name
438 * @dev: LED controller device object
439 * @init_data: the LED class device initialization data
440 * @led_classdev_name: composed LED class device name
442 * Create LED class device name basing on the provided init_data argument.
443 * The name can have <devicename:color:function> or <color:function>.
444 * form, depending on the init_data configuration.
446 * Returns: 0 on success or negative error value on failure
448 int led_compose_name(struct device *dev, struct led_init_data *init_data,
449 char *led_classdev_name);
452 * led_get_color_name - get string representation of color ID
453 * @color_id: The LED_COLOR_ID_* constant
455 * Get the string name of a LED_COLOR_ID_* constant.
457 * Returns: A string constant or NULL on an invalid ID.
459 const char *led_get_color_name(u8 color_id);
462 * led_sysfs_is_disabled - check if LED sysfs interface is disabled
463 * @led_cdev: the LED to query
465 * Returns: true if the led_cdev's sysfs interface is disabled.
467 static inline bool led_sysfs_is_disabled(struct led_classdev *led_cdev)
469 return led_cdev->flags & LED_SYSFS_DISABLE;
475 /* Registration functions for simple triggers */
476 #define DEFINE_LED_TRIGGER(x) static struct led_trigger *x;
477 #define DEFINE_LED_TRIGGER_GLOBAL(x) struct led_trigger *x;
479 #ifdef CONFIG_LEDS_TRIGGERS
481 #define TRIG_NAME_MAX 50
484 /* Trigger Properties */
486 int (*activate)(struct led_classdev *led_cdev);
487 void (*deactivate)(struct led_classdev *led_cdev);
489 /* Brightness set by led_trigger_event */
490 enum led_brightness brightness;
492 /* LED-private triggers have this set */
493 struct led_hw_trigger_type *trigger_type;
495 /* LEDs under control by this trigger (for simple triggers) */
496 spinlock_t leddev_list_lock;
497 struct list_head led_cdevs;
499 /* Link to next registered trigger */
500 struct list_head next_trig;
502 const struct attribute_group **groups;
506 * Currently the attributes in struct led_trigger::groups are added directly to
507 * the LED device. As this might change in the future, the following
508 * macros abstract getting the LED device and its trigger_data from the dev
509 * parameter passed to the attribute accessor functions.
511 #define led_trigger_get_led(dev) ((struct led_classdev *)dev_get_drvdata((dev)))
512 #define led_trigger_get_drvdata(dev) (led_get_trigger_data(led_trigger_get_led(dev)))
514 /* Registration functions for complex triggers */
515 int led_trigger_register(struct led_trigger *trigger);
516 void led_trigger_unregister(struct led_trigger *trigger);
517 int devm_led_trigger_register(struct device *dev,
518 struct led_trigger *trigger);
520 void led_trigger_register_simple(const char *name,
521 struct led_trigger **trigger);
522 void led_trigger_unregister_simple(struct led_trigger *trigger);
523 void led_trigger_event(struct led_trigger *trigger, enum led_brightness event);
524 void led_mc_trigger_event(struct led_trigger *trig,
525 unsigned int *intensity_value, unsigned int num_colors,
526 enum led_brightness brightness);
527 void led_trigger_blink(struct led_trigger *trigger, unsigned long delay_on,
528 unsigned long delay_off);
529 void led_trigger_blink_oneshot(struct led_trigger *trigger,
530 unsigned long delay_on,
531 unsigned long delay_off,
533 void led_trigger_set_default(struct led_classdev *led_cdev);
534 int led_trigger_set(struct led_classdev *led_cdev, struct led_trigger *trigger);
535 void led_trigger_remove(struct led_classdev *led_cdev);
537 static inline void led_set_trigger_data(struct led_classdev *led_cdev,
540 led_cdev->trigger_data = trigger_data;
543 static inline void *led_get_trigger_data(struct led_classdev *led_cdev)
545 return led_cdev->trigger_data;
548 static inline enum led_brightness
549 led_trigger_get_brightness(const struct led_trigger *trigger)
551 return trigger ? trigger->brightness : LED_OFF;
554 #define module_led_trigger(__led_trigger) \
555 module_driver(__led_trigger, led_trigger_register, \
556 led_trigger_unregister)
560 /* Trigger has no members */
561 struct led_trigger {};
563 /* Trigger inline empty functions */
564 static inline void led_trigger_register_simple(const char *name,
565 struct led_trigger **trigger) {}
566 static inline void led_trigger_unregister_simple(struct led_trigger *trigger) {}
567 static inline void led_trigger_event(struct led_trigger *trigger,
568 enum led_brightness event) {}
569 static inline void led_mc_trigger_event(struct led_trigger *trig,
570 unsigned int *intensity_value, unsigned int num_colors,
571 enum led_brightness brightness) {}
572 static inline void led_trigger_blink(struct led_trigger *trigger,
573 unsigned long delay_on,
574 unsigned long delay_off) {}
575 static inline void led_trigger_blink_oneshot(struct led_trigger *trigger,
576 unsigned long delay_on,
577 unsigned long delay_off,
579 static inline void led_trigger_set_default(struct led_classdev *led_cdev) {}
580 static inline int led_trigger_set(struct led_classdev *led_cdev,
581 struct led_trigger *trigger)
586 static inline void led_trigger_remove(struct led_classdev *led_cdev) {}
587 static inline void led_set_trigger_data(struct led_classdev *led_cdev) {}
588 static inline void *led_get_trigger_data(struct led_classdev *led_cdev)
593 static inline enum led_brightness
594 led_trigger_get_brightness(const struct led_trigger *trigger)
599 #endif /* CONFIG_LEDS_TRIGGERS */
601 /* Trigger specific enum */
602 enum led_trigger_netdev_modes {
603 TRIGGER_NETDEV_LINK = 0,
604 TRIGGER_NETDEV_LINK_10,
605 TRIGGER_NETDEV_LINK_100,
606 TRIGGER_NETDEV_LINK_1000,
607 TRIGGER_NETDEV_LINK_2500,
608 TRIGGER_NETDEV_LINK_5000,
609 TRIGGER_NETDEV_LINK_10000,
610 TRIGGER_NETDEV_HALF_DUPLEX,
611 TRIGGER_NETDEV_FULL_DUPLEX,
616 __TRIGGER_NETDEV_MAX,
619 /* Trigger specific functions */
620 #ifdef CONFIG_LEDS_TRIGGER_DISK
621 void ledtrig_disk_activity(bool write);
623 static inline void ledtrig_disk_activity(bool write) {}
626 #ifdef CONFIG_LEDS_TRIGGER_MTD
627 void ledtrig_mtd_activity(void);
629 static inline void ledtrig_mtd_activity(void) {}
632 #if defined(CONFIG_LEDS_TRIGGER_CAMERA) || defined(CONFIG_LEDS_TRIGGER_CAMERA_MODULE)
633 void ledtrig_flash_ctrl(bool on);
634 void ledtrig_torch_ctrl(bool on);
636 static inline void ledtrig_flash_ctrl(bool on) {}
637 static inline void ledtrig_torch_ctrl(bool on) {}
641 * Generic LED platform data for describing LED names and default triggers.
645 const char *default_trigger;
649 struct led_platform_data {
651 struct led_info *leds;
654 struct led_properties {
657 const char *function;
659 bool func_enum_present;
663 typedef int (*gpio_blink_set_t)(struct gpio_desc *desc, int state,
664 unsigned long *delay_on,
665 unsigned long *delay_off);
667 /* For the leds-gpio driver */
670 const char *default_trigger;
672 unsigned active_low : 1;
673 unsigned retain_state_suspended : 1;
674 unsigned panic_indicator : 1;
675 unsigned default_state : 2;
676 unsigned retain_state_shutdown : 1;
677 /* default_state should be one of LEDS_GPIO_DEFSTATE_(ON|OFF|KEEP) */
678 struct gpio_desc *gpiod;
680 #define LEDS_GPIO_DEFSTATE_OFF LEDS_DEFSTATE_OFF
681 #define LEDS_GPIO_DEFSTATE_ON LEDS_DEFSTATE_ON
682 #define LEDS_GPIO_DEFSTATE_KEEP LEDS_DEFSTATE_KEEP
684 struct gpio_led_platform_data {
686 const struct gpio_led *leds;
688 #define GPIO_LED_NO_BLINK_LOW 0 /* No blink GPIO state low */
689 #define GPIO_LED_NO_BLINK_HIGH 1 /* No blink GPIO state high */
690 #define GPIO_LED_BLINK 2 /* Please, blink */
691 gpio_blink_set_t gpio_blink_set;
694 #ifdef CONFIG_LEDS_GPIO_REGISTER
695 struct platform_device *gpio_led_register_device(
696 int id, const struct gpio_led_platform_data *pdata);
698 static inline struct platform_device *gpio_led_register_device(
699 int id, const struct gpio_led_platform_data *pdata)
706 CPU_LED_IDLE_START, /* CPU enters idle */
707 CPU_LED_IDLE_END, /* CPU idle ends */
708 CPU_LED_START, /* Machine starts, especially resume */
709 CPU_LED_STOP, /* Machine stops, especially suspend */
710 CPU_LED_HALTED, /* Machine shutdown */
712 #ifdef CONFIG_LEDS_TRIGGER_CPU
713 void ledtrig_cpu(enum cpu_led_event evt);
715 static inline void ledtrig_cpu(enum cpu_led_event evt)
721 #ifdef CONFIG_LEDS_BRIGHTNESS_HW_CHANGED
722 void led_classdev_notify_brightness_hw_changed(
723 struct led_classdev *led_cdev, unsigned int brightness);
725 static inline void led_classdev_notify_brightness_hw_changed(
726 struct led_classdev *led_cdev, enum led_brightness brightness) { }
730 * struct led_pattern - pattern interval settings
731 * @delta_t: pattern interval delay, in milliseconds
732 * @brightness: pattern interval brightness
740 LED_AUDIO_MUTE, /* master mute LED */
741 LED_AUDIO_MICMUTE, /* mic mute LED */
745 #endif /* __LINUX_LEDS_H_INCLUDED */