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32 /* This is obsolete/useless.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 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)
111 /* set_brightness_work / blink_timer flags, atomic, private. */
112 unsigned long work_flags;
114 #define LED_BLINK_SW 0
115 #define LED_BLINK_ONESHOT 1
116 #define LED_BLINK_ONESHOT_STOP 2
117 #define LED_BLINK_INVERT 3
118 #define LED_BLINK_BRIGHTNESS_CHANGE 4
119 #define LED_BLINK_DISABLE 5
120 /* Brightness off also disables hw-blinking so it is a separate action */
121 #define LED_SET_BRIGHTNESS_OFF 6
122 #define LED_SET_BRIGHTNESS 7
123 #define LED_SET_BLINK 8
125 /* Set LED brightness level
126 * Must not sleep. Use brightness_set_blocking for drivers
127 * that can sleep while setting brightness.
129 void (*brightness_set)(struct led_classdev *led_cdev,
130 enum led_brightness brightness);
132 * Set LED brightness level immediately - it can block the caller for
133 * the time required for accessing a LED device register.
135 int (*brightness_set_blocking)(struct led_classdev *led_cdev,
136 enum led_brightness brightness);
137 /* Get LED brightness level */
138 enum led_brightness (*brightness_get)(struct led_classdev *led_cdev);
141 * Activate hardware accelerated blink, delays are in milliseconds
142 * and if both are zero then a sensible default should be chosen.
143 * The call should adjust the timings in that case and if it can't
144 * match the values specified exactly.
145 * Deactivate blinking again when the brightness is set to LED_OFF
146 * via the brightness_set() callback.
147 * For led_blink_set_nosleep() the LED core assumes that blink_set
148 * implementations, of drivers which do not use brightness_set_blocking,
149 * will not sleep. Therefor if brightness_set_blocking is not set
150 * this function must not sleep!
152 int (*blink_set)(struct led_classdev *led_cdev,
153 unsigned long *delay_on,
154 unsigned long *delay_off);
156 int (*pattern_set)(struct led_classdev *led_cdev,
157 struct led_pattern *pattern, u32 len, int repeat);
158 int (*pattern_clear)(struct led_classdev *led_cdev);
161 const struct attribute_group **groups;
163 struct list_head node; /* LED Device list */
164 const char *default_trigger; /* Trigger to use */
166 unsigned long blink_delay_on, blink_delay_off;
167 struct timer_list blink_timer;
168 int blink_brightness;
169 int new_blink_brightness;
170 void (*flash_resume)(struct led_classdev *led_cdev);
172 struct work_struct set_brightness_work;
173 int delayed_set_value;
174 unsigned long delayed_delay_on;
175 unsigned long delayed_delay_off;
177 #ifdef CONFIG_LEDS_TRIGGERS
178 /* Protects the trigger data below */
179 struct rw_semaphore trigger_lock;
181 struct led_trigger *trigger;
182 struct list_head trig_list;
184 /* true if activated - deactivate routine uses it to do cleanup */
187 /* LEDs that have private triggers have this set */
188 struct led_hw_trigger_type *trigger_type;
190 /* Unique trigger name supported by LED set in hw control mode */
191 const char *hw_control_trigger;
193 * Check if the LED driver supports the requested mode provided by the
194 * defined supported trigger to setup the LED to hw control mode.
196 * Return 0 on success. Return -EOPNOTSUPP when the passed flags are not
197 * supported and software fallback needs to be used.
198 * Return a negative error number on any other case for check fail due
199 * to various reason like device not ready or timeouts.
201 int (*hw_control_is_supported)(struct led_classdev *led_cdev,
202 unsigned long flags);
204 * Activate hardware control, LED driver will use the provided flags
205 * from the supported trigger and setup the LED to be driven by hardware
206 * following the requested mode from the trigger flags.
207 * Deactivate hardware blink control by setting brightness to LED_OFF via
208 * the brightness_set() callback.
210 * Return 0 on success, a negative error number on flags apply fail.
212 int (*hw_control_set)(struct led_classdev *led_cdev,
213 unsigned long flags);
215 * Get from the LED driver the current mode that the LED is set in hw
216 * control mode and put them in flags.
217 * Trigger can use this to get the initial state of a LED already set in
218 * hardware blink control.
220 * Return 0 on success, a negative error number on failing parsing the
221 * initial mode. Error from this function is NOT FATAL as the device
222 * may be in a not supported initial state by the attached LED trigger.
224 int (*hw_control_get)(struct led_classdev *led_cdev,
225 unsigned long *flags);
227 * Get the device this LED blinks in response to.
228 * e.g. for a PHY LED, it is the network device. If the LED is
229 * not yet associated to a device, return NULL.
231 struct device *(*hw_control_get_device)(struct led_classdev *led_cdev);
234 #ifdef CONFIG_LEDS_BRIGHTNESS_HW_CHANGED
235 int brightness_hw_changed;
236 struct kernfs_node *brightness_hw_changed_kn;
239 /* Ensures consistent access to the LED Flash Class device */
240 struct mutex led_access;
244 * led_classdev_register_ext - register a new object of LED class with
246 * @parent: LED controller device this LED is driven by
247 * @led_cdev: the led_classdev structure for this device
248 * @init_data: the LED class device initialization data
250 * Register a new object of LED class, with name derived from init_data.
252 * Returns: 0 on success or negative error value on failure
254 int led_classdev_register_ext(struct device *parent,
255 struct led_classdev *led_cdev,
256 struct led_init_data *init_data);
259 * led_classdev_register - register a new object of LED class
260 * @parent: LED controller device this LED is driven by
261 * @led_cdev: the led_classdev structure for this device
263 * Register a new object of LED class, with name derived from the name property
264 * of passed led_cdev argument.
266 * Returns: 0 on success or negative error value on failure
268 static inline int led_classdev_register(struct device *parent,
269 struct led_classdev *led_cdev)
271 return led_classdev_register_ext(parent, led_cdev, NULL);
274 int devm_led_classdev_register_ext(struct device *parent,
275 struct led_classdev *led_cdev,
276 struct led_init_data *init_data);
277 static inline int devm_led_classdev_register(struct device *parent,
278 struct led_classdev *led_cdev)
280 return devm_led_classdev_register_ext(parent, led_cdev, NULL);
282 void led_classdev_unregister(struct led_classdev *led_cdev);
283 void devm_led_classdev_unregister(struct device *parent,
284 struct led_classdev *led_cdev);
285 void led_classdev_suspend(struct led_classdev *led_cdev);
286 void led_classdev_resume(struct led_classdev *led_cdev);
288 void led_add_lookup(struct led_lookup_data *led_lookup);
289 void led_remove_lookup(struct led_lookup_data *led_lookup);
291 struct led_classdev *__must_check led_get(struct device *dev, char *con_id);
292 struct led_classdev *__must_check devm_led_get(struct device *dev, char *con_id);
294 extern struct led_classdev *of_led_get(struct device_node *np, int index);
295 extern void led_put(struct led_classdev *led_cdev);
296 struct led_classdev *__must_check devm_of_led_get(struct device *dev,
298 struct led_classdev *__must_check devm_of_led_get_optional(struct device *dev,
302 * led_blink_set - set blinking with software fallback
303 * @led_cdev: the LED to start blinking
304 * @delay_on: the time it should be on (in ms)
305 * @delay_off: the time it should ble off (in ms)
307 * This function makes the LED blink, attempting to use the
308 * hardware acceleration if possible, but falling back to
309 * software blinking if there is no hardware blinking or if
310 * the LED refuses the passed values.
312 * This function may sleep!
314 * Note that if software blinking is active, simply calling
315 * led_cdev->brightness_set() will not stop the blinking,
316 * use led_set_brightness() instead.
318 void led_blink_set(struct led_classdev *led_cdev, unsigned long *delay_on,
319 unsigned long *delay_off);
322 * led_blink_set_nosleep - set blinking, guaranteed to not sleep
323 * @led_cdev: the LED to start blinking
324 * @delay_on: the time it should be on (in ms)
325 * @delay_off: the time it should ble off (in ms)
327 * This function makes the LED blink and is guaranteed to not sleep. Otherwise
328 * this is the same as led_blink_set(), see led_blink_set() for details.
330 void led_blink_set_nosleep(struct led_classdev *led_cdev, unsigned long delay_on,
331 unsigned long delay_off);
334 * led_blink_set_oneshot - do a oneshot software blink
335 * @led_cdev: the LED to start blinking
336 * @delay_on: the time it should be on (in ms)
337 * @delay_off: the time it should ble off (in ms)
338 * @invert: blink off, then on, leaving the led on
340 * This function makes the LED blink one time for delay_on +
341 * delay_off time, ignoring the request if another one-shot
342 * blink is already in progress.
344 * If invert is set, led blinks for delay_off first, then for
345 * delay_on and leave the led on after the on-off cycle.
347 * This function is guaranteed not to sleep.
349 void led_blink_set_oneshot(struct led_classdev *led_cdev,
350 unsigned long *delay_on, unsigned long *delay_off,
353 * led_set_brightness - set LED brightness
354 * @led_cdev: the LED to set
355 * @brightness: the brightness to set it to
357 * Set an LED's brightness, and, if necessary, cancel the
358 * software blink timer that implements blinking when the
359 * hardware doesn't. This function is guaranteed not to sleep.
361 void led_set_brightness(struct led_classdev *led_cdev, unsigned int brightness);
364 * led_set_brightness_sync - set LED brightness synchronously
365 * @led_cdev: the LED to set
366 * @value: the brightness to set it to
368 * Set an LED's brightness immediately. This function will block
369 * the caller for the time required for accessing device registers,
372 * Returns: 0 on success or negative error value on failure
374 int led_set_brightness_sync(struct led_classdev *led_cdev, unsigned int value);
377 * led_update_brightness - update LED brightness
378 * @led_cdev: the LED to query
380 * Get an LED's current brightness and update led_cdev->brightness
381 * member with the obtained value.
383 * Returns: 0 on success or negative error value on failure
385 int led_update_brightness(struct led_classdev *led_cdev);
388 * led_get_default_pattern - return default pattern
390 * @led_cdev: the LED to get default pattern for
391 * @size: pointer for storing the number of elements in returned array,
392 * modified only if return != NULL
394 * Return: Allocated array of integers with default pattern from device tree
395 * or NULL. Caller is responsible for kfree().
397 u32 *led_get_default_pattern(struct led_classdev *led_cdev, unsigned int *size);
400 * led_sysfs_disable - disable LED sysfs interface
401 * @led_cdev: the LED to set
403 * Disable the led_cdev's sysfs interface.
405 void led_sysfs_disable(struct led_classdev *led_cdev);
408 * led_sysfs_enable - enable LED sysfs interface
409 * @led_cdev: the LED to set
411 * Enable the led_cdev's sysfs interface.
413 void led_sysfs_enable(struct led_classdev *led_cdev);
416 * led_compose_name - compose LED class device name
417 * @dev: LED controller device object
418 * @init_data: the LED class device initialization data
419 * @led_classdev_name: composed LED class device name
421 * Create LED class device name basing on the provided init_data argument.
422 * The name can have <devicename:color:function> or <color:function>.
423 * form, depending on the init_data configuration.
425 * Returns: 0 on success or negative error value on failure
427 int led_compose_name(struct device *dev, struct led_init_data *init_data,
428 char *led_classdev_name);
431 * led_sysfs_is_disabled - check if LED sysfs interface is disabled
432 * @led_cdev: the LED to query
434 * Returns: true if the led_cdev's sysfs interface is disabled.
436 static inline bool led_sysfs_is_disabled(struct led_classdev *led_cdev)
438 return led_cdev->flags & LED_SYSFS_DISABLE;
444 /* Registration functions for simple triggers */
445 #define DEFINE_LED_TRIGGER(x) static struct led_trigger *x;
446 #define DEFINE_LED_TRIGGER_GLOBAL(x) struct led_trigger *x;
448 #ifdef CONFIG_LEDS_TRIGGERS
450 #define TRIG_NAME_MAX 50
453 /* Trigger Properties */
455 int (*activate)(struct led_classdev *led_cdev);
456 void (*deactivate)(struct led_classdev *led_cdev);
458 /* LED-private triggers have this set */
459 struct led_hw_trigger_type *trigger_type;
461 /* LEDs under control by this trigger (for simple triggers) */
462 spinlock_t leddev_list_lock;
463 struct list_head led_cdevs;
465 /* Link to next registered trigger */
466 struct list_head next_trig;
468 const struct attribute_group **groups;
472 * Currently the attributes in struct led_trigger::groups are added directly to
473 * the LED device. As this might change in the future, the following
474 * macros abstract getting the LED device and its trigger_data from the dev
475 * parameter passed to the attribute accessor functions.
477 #define led_trigger_get_led(dev) ((struct led_classdev *)dev_get_drvdata((dev)))
478 #define led_trigger_get_drvdata(dev) (led_get_trigger_data(led_trigger_get_led(dev)))
480 /* Registration functions for complex triggers */
481 int led_trigger_register(struct led_trigger *trigger);
482 void led_trigger_unregister(struct led_trigger *trigger);
483 int devm_led_trigger_register(struct device *dev,
484 struct led_trigger *trigger);
486 void led_trigger_register_simple(const char *name,
487 struct led_trigger **trigger);
488 void led_trigger_unregister_simple(struct led_trigger *trigger);
489 void led_trigger_event(struct led_trigger *trigger, enum led_brightness event);
490 void led_trigger_blink(struct led_trigger *trigger, unsigned long delay_on,
491 unsigned long delay_off);
492 void led_trigger_blink_oneshot(struct led_trigger *trigger,
493 unsigned long delay_on,
494 unsigned long delay_off,
496 void led_trigger_set_default(struct led_classdev *led_cdev);
497 int led_trigger_set(struct led_classdev *led_cdev, struct led_trigger *trigger);
498 void led_trigger_remove(struct led_classdev *led_cdev);
500 static inline void led_set_trigger_data(struct led_classdev *led_cdev,
503 led_cdev->trigger_data = trigger_data;
506 static inline void *led_get_trigger_data(struct led_classdev *led_cdev)
508 return led_cdev->trigger_data;
511 #define module_led_trigger(__led_trigger) \
512 module_driver(__led_trigger, led_trigger_register, \
513 led_trigger_unregister)
517 /* Trigger has no members */
518 struct led_trigger {};
520 /* Trigger inline empty functions */
521 static inline void led_trigger_register_simple(const char *name,
522 struct led_trigger **trigger) {}
523 static inline void led_trigger_unregister_simple(struct led_trigger *trigger) {}
524 static inline void led_trigger_event(struct led_trigger *trigger,
525 enum led_brightness event) {}
526 static inline void led_trigger_blink(struct led_trigger *trigger,
527 unsigned long delay_on,
528 unsigned long delay_off) {}
529 static inline void led_trigger_blink_oneshot(struct led_trigger *trigger,
530 unsigned long delay_on,
531 unsigned long delay_off,
533 static inline void led_trigger_set_default(struct led_classdev *led_cdev) {}
534 static inline int led_trigger_set(struct led_classdev *led_cdev,
535 struct led_trigger *trigger)
540 static inline void led_trigger_remove(struct led_classdev *led_cdev) {}
541 static inline void led_set_trigger_data(struct led_classdev *led_cdev) {}
542 static inline void *led_get_trigger_data(struct led_classdev *led_cdev)
547 #endif /* CONFIG_LEDS_TRIGGERS */
549 /* Trigger specific enum */
550 enum led_trigger_netdev_modes {
551 TRIGGER_NETDEV_LINK = 0,
552 TRIGGER_NETDEV_LINK_10,
553 TRIGGER_NETDEV_LINK_100,
554 TRIGGER_NETDEV_LINK_1000,
555 TRIGGER_NETDEV_LINK_2500,
556 TRIGGER_NETDEV_LINK_5000,
557 TRIGGER_NETDEV_LINK_10000,
558 TRIGGER_NETDEV_HALF_DUPLEX,
559 TRIGGER_NETDEV_FULL_DUPLEX,
564 __TRIGGER_NETDEV_MAX,
567 /* Trigger specific functions */
568 #ifdef CONFIG_LEDS_TRIGGER_DISK
569 void ledtrig_disk_activity(bool write);
571 static inline void ledtrig_disk_activity(bool write) {}
574 #ifdef CONFIG_LEDS_TRIGGER_MTD
575 void ledtrig_mtd_activity(void);
577 static inline void ledtrig_mtd_activity(void) {}
580 #if defined(CONFIG_LEDS_TRIGGER_CAMERA) || defined(CONFIG_LEDS_TRIGGER_CAMERA_MODULE)
581 void ledtrig_flash_ctrl(bool on);
582 void ledtrig_torch_ctrl(bool on);
584 static inline void ledtrig_flash_ctrl(bool on) {}
585 static inline void ledtrig_torch_ctrl(bool on) {}
589 * Generic LED platform data for describing LED names and default triggers.
593 const char *default_trigger;
597 struct led_platform_data {
599 struct led_info *leds;
602 struct led_properties {
605 const char *function;
607 bool func_enum_present;
611 typedef int (*gpio_blink_set_t)(struct gpio_desc *desc, int state,
612 unsigned long *delay_on,
613 unsigned long *delay_off);
615 /* For the leds-gpio driver */
618 const char *default_trigger;
620 unsigned active_low : 1;
621 unsigned retain_state_suspended : 1;
622 unsigned panic_indicator : 1;
623 unsigned default_state : 2;
624 unsigned retain_state_shutdown : 1;
625 /* default_state should be one of LEDS_GPIO_DEFSTATE_(ON|OFF|KEEP) */
626 struct gpio_desc *gpiod;
628 #define LEDS_GPIO_DEFSTATE_OFF LEDS_DEFSTATE_OFF
629 #define LEDS_GPIO_DEFSTATE_ON LEDS_DEFSTATE_ON
630 #define LEDS_GPIO_DEFSTATE_KEEP LEDS_DEFSTATE_KEEP
632 struct gpio_led_platform_data {
634 const struct gpio_led *leds;
636 #define GPIO_LED_NO_BLINK_LOW 0 /* No blink GPIO state low */
637 #define GPIO_LED_NO_BLINK_HIGH 1 /* No blink GPIO state high */
638 #define GPIO_LED_BLINK 2 /* Please, blink */
639 gpio_blink_set_t gpio_blink_set;
642 #ifdef CONFIG_LEDS_GPIO_REGISTER
643 struct platform_device *gpio_led_register_device(
644 int id, const struct gpio_led_platform_data *pdata);
646 static inline struct platform_device *gpio_led_register_device(
647 int id, const struct gpio_led_platform_data *pdata)
654 CPU_LED_IDLE_START, /* CPU enters idle */
655 CPU_LED_IDLE_END, /* CPU idle ends */
656 CPU_LED_START, /* Machine starts, especially resume */
657 CPU_LED_STOP, /* Machine stops, especially suspend */
658 CPU_LED_HALTED, /* Machine shutdown */
660 #ifdef CONFIG_LEDS_TRIGGER_CPU
661 void ledtrig_cpu(enum cpu_led_event evt);
663 static inline void ledtrig_cpu(enum cpu_led_event evt)
669 #ifdef CONFIG_LEDS_BRIGHTNESS_HW_CHANGED
670 void led_classdev_notify_brightness_hw_changed(
671 struct led_classdev *led_cdev, unsigned int brightness);
673 static inline void led_classdev_notify_brightness_hw_changed(
674 struct led_classdev *led_cdev, enum led_brightness brightness) { }
678 * struct led_pattern - pattern interval settings
679 * @delta_t: pattern interval delay, in milliseconds
680 * @brightness: pattern interval brightness
688 LED_AUDIO_MUTE, /* master mute LED */
689 LED_AUDIO_MICMUTE, /* mic mute LED */
693 #if IS_ENABLED(CONFIG_LEDS_TRIGGER_AUDIO)
694 enum led_brightness ledtrig_audio_get(enum led_audio type);
695 void ledtrig_audio_set(enum led_audio type, enum led_brightness state);
697 static inline enum led_brightness ledtrig_audio_get(enum led_audio type)
701 static inline void ledtrig_audio_set(enum led_audio type,
702 enum led_brightness state)
707 #endif /* __LINUX_LEDS_H_INCLUDED */