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>
36 enum led_brightness brightness
;
37 enum led_brightness max_brightness
;
40 /* Lower 16 bits reflect status */
41 #define LED_SUSPENDED (1 << 0)
42 /* Upper 16 bits reflect control information */
43 #define LED_CORE_SUSPENDRESUME (1 << 16)
44 #define LED_BLINK_ONESHOT (1 << 17)
45 #define LED_BLINK_ONESHOT_STOP (1 << 18)
46 #define LED_BLINK_INVERT (1 << 19)
47 #define LED_BLINK_BRIGHTNESS_CHANGE (1 << 20)
48 #define LED_BLINK_DISABLE (1 << 21)
49 #define LED_SYSFS_DISABLE (1 << 22)
50 #define LED_DEV_CAP_FLASH (1 << 23)
52 /* Set LED brightness level */
53 /* Must not sleep, use a workqueue if needed */
54 void (*brightness_set
)(struct led_classdev
*led_cdev
,
55 enum led_brightness brightness
);
57 * Set LED brightness level immediately - it can block the caller for
58 * the time required for accessing a LED device register.
60 int (*brightness_set_blocking
)(struct led_classdev
*led_cdev
,
61 enum led_brightness brightness
);
62 /* Get LED brightness level */
63 enum led_brightness (*brightness_get
)(struct led_classdev
*led_cdev
);
66 * Activate hardware accelerated blink, delays are in milliseconds
67 * and if both are zero then a sensible default should be chosen.
68 * The call should adjust the timings in that case and if it can't
69 * match the values specified exactly.
70 * Deactivate blinking again when the brightness is set to a fixed
71 * value via the brightness_set() callback.
73 int (*blink_set
)(struct led_classdev
*led_cdev
,
74 unsigned long *delay_on
,
75 unsigned long *delay_off
);
78 const struct attribute_group
**groups
;
80 struct list_head node
; /* LED Device list */
81 const char *default_trigger
; /* Trigger to use */
83 unsigned long blink_delay_on
, blink_delay_off
;
84 struct timer_list blink_timer
;
86 void (*flash_resume
)(struct led_classdev
*led_cdev
);
88 struct work_struct set_brightness_work
;
89 int delayed_set_value
;
91 #ifdef CONFIG_LEDS_TRIGGERS
92 /* Protects the trigger data below */
93 struct rw_semaphore trigger_lock
;
95 struct led_trigger
*trigger
;
96 struct list_head trig_list
;
98 /* true if activated - deactivate routine uses it to do cleanup */
102 /* Ensures consistent access to the LED Flash Class device */
103 struct mutex led_access
;
106 extern int led_classdev_register(struct device
*parent
,
107 struct led_classdev
*led_cdev
);
108 extern int devm_led_classdev_register(struct device
*parent
,
109 struct led_classdev
*led_cdev
);
110 extern void led_classdev_unregister(struct led_classdev
*led_cdev
);
111 extern void devm_led_classdev_unregister(struct device
*parent
,
112 struct led_classdev
*led_cdev
);
113 extern void led_classdev_suspend(struct led_classdev
*led_cdev
);
114 extern void led_classdev_resume(struct led_classdev
*led_cdev
);
117 * led_blink_set - set blinking with software fallback
118 * @led_cdev: the LED to start blinking
119 * @delay_on: the time it should be on (in ms)
120 * @delay_off: the time it should ble off (in ms)
122 * This function makes the LED blink, attempting to use the
123 * hardware acceleration if possible, but falling back to
124 * software blinking if there is no hardware blinking or if
125 * the LED refuses the passed values.
127 * Note that if software blinking is active, simply calling
128 * led_cdev->brightness_set() will not stop the blinking,
129 * use led_classdev_brightness_set() instead.
131 extern void led_blink_set(struct led_classdev
*led_cdev
,
132 unsigned long *delay_on
,
133 unsigned long *delay_off
);
135 * led_blink_set_oneshot - do a oneshot software blink
136 * @led_cdev: the LED to start blinking
137 * @delay_on: the time it should be on (in ms)
138 * @delay_off: the time it should ble off (in ms)
139 * @invert: blink off, then on, leaving the led on
141 * This function makes the LED blink one time for delay_on +
142 * delay_off time, ignoring the request if another one-shot
143 * blink is already in progress.
145 * If invert is set, led blinks for delay_off first, then for
146 * delay_on and leave the led on after the on-off cycle.
148 extern void led_blink_set_oneshot(struct led_classdev
*led_cdev
,
149 unsigned long *delay_on
,
150 unsigned long *delay_off
,
153 * led_set_brightness - set LED brightness
154 * @led_cdev: the LED to set
155 * @brightness: the brightness to set it to
157 * Set an LED's brightness, and, if necessary, cancel the
158 * software blink timer that implements blinking when the
159 * hardware doesn't. This function is guaranteed not to sleep.
161 extern void led_set_brightness(struct led_classdev
*led_cdev
,
162 enum led_brightness brightness
);
165 * led_set_brightness_sync - set LED brightness synchronously
166 * @led_cdev: the LED to set
167 * @brightness: the brightness to set it to
169 * Set an LED's brightness immediately. This function will block
170 * the caller for the time required for accessing device registers,
173 * Returns: 0 on success or negative error value on failure
175 extern int led_set_brightness_sync(struct led_classdev
*led_cdev
,
176 enum led_brightness value
);
179 * led_update_brightness - update LED brightness
180 * @led_cdev: the LED to query
182 * Get an LED's current brightness and update led_cdev->brightness
183 * member with the obtained value.
185 * Returns: 0 on success or negative error value on failure
187 extern int led_update_brightness(struct led_classdev
*led_cdev
);
190 * led_sysfs_disable - disable LED sysfs interface
191 * @led_cdev: the LED to set
193 * Disable the led_cdev's sysfs interface.
195 extern void led_sysfs_disable(struct led_classdev
*led_cdev
);
198 * led_sysfs_enable - enable LED sysfs interface
199 * @led_cdev: the LED to set
201 * Enable the led_cdev's sysfs interface.
203 extern void led_sysfs_enable(struct led_classdev
*led_cdev
);
206 * led_sysfs_is_disabled - check if LED sysfs interface is disabled
207 * @led_cdev: the LED to query
209 * Returns: true if the led_cdev's sysfs interface is disabled.
211 static inline bool led_sysfs_is_disabled(struct led_classdev
*led_cdev
)
213 return led_cdev
->flags
& LED_SYSFS_DISABLE
;
219 /* Registration functions for simple triggers */
220 #define DEFINE_LED_TRIGGER(x) static struct led_trigger *x;
221 #define DEFINE_LED_TRIGGER_GLOBAL(x) struct led_trigger *x;
223 #ifdef CONFIG_LEDS_TRIGGERS
225 #define TRIG_NAME_MAX 50
228 /* Trigger Properties */
230 void (*activate
)(struct led_classdev
*led_cdev
);
231 void (*deactivate
)(struct led_classdev
*led_cdev
);
233 /* LEDs under control by this trigger (for simple triggers) */
234 rwlock_t leddev_list_lock
;
235 struct list_head led_cdevs
;
237 /* Link to next registered trigger */
238 struct list_head next_trig
;
241 ssize_t
led_trigger_store(struct device
*dev
, struct device_attribute
*attr
,
242 const char *buf
, size_t count
);
243 ssize_t
led_trigger_show(struct device
*dev
, struct device_attribute
*attr
,
246 /* Registration functions for complex triggers */
247 extern int led_trigger_register(struct led_trigger
*trigger
);
248 extern void led_trigger_unregister(struct led_trigger
*trigger
);
250 extern void led_trigger_register_simple(const char *name
,
251 struct led_trigger
**trigger
);
252 extern void led_trigger_unregister_simple(struct led_trigger
*trigger
);
253 extern void led_trigger_event(struct led_trigger
*trigger
,
254 enum led_brightness event
);
255 extern void led_trigger_blink(struct led_trigger
*trigger
,
256 unsigned long *delay_on
,
257 unsigned long *delay_off
);
258 extern void led_trigger_blink_oneshot(struct led_trigger
*trigger
,
259 unsigned long *delay_on
,
260 unsigned long *delay_off
,
262 extern void led_trigger_set_default(struct led_classdev
*led_cdev
);
263 extern void led_trigger_set(struct led_classdev
*led_cdev
,
264 struct led_trigger
*trigger
);
265 extern void led_trigger_remove(struct led_classdev
*led_cdev
);
267 static inline void *led_get_trigger_data(struct led_classdev
*led_cdev
)
269 return led_cdev
->trigger_data
;
273 * led_trigger_rename_static - rename a trigger
274 * @name: the new trigger name
275 * @trig: the LED trigger to rename
277 * Change a LED trigger name by copying the string passed in
278 * name into current trigger name, which MUST be large
279 * enough for the new string.
281 * Note that name must NOT point to the same string used
282 * during LED registration, as that could lead to races.
284 * This is meant to be used on triggers with statically
287 extern void led_trigger_rename_static(const char *name
,
288 struct led_trigger
*trig
);
292 /* Trigger has no members */
293 struct led_trigger
{};
295 /* Trigger inline empty functions */
296 static inline void led_trigger_register_simple(const char *name
,
297 struct led_trigger
**trigger
) {}
298 static inline void led_trigger_unregister_simple(struct led_trigger
*trigger
) {}
299 static inline void led_trigger_event(struct led_trigger
*trigger
,
300 enum led_brightness event
) {}
301 static inline void led_trigger_blink(struct led_trigger
*trigger
,
302 unsigned long *delay_on
,
303 unsigned long *delay_off
) {}
304 static inline void led_trigger_blink_oneshot(struct led_trigger
*trigger
,
305 unsigned long *delay_on
,
306 unsigned long *delay_off
,
308 static inline void led_trigger_set_default(struct led_classdev
*led_cdev
) {}
309 static inline void led_trigger_set(struct led_classdev
*led_cdev
,
310 struct led_trigger
*trigger
) {}
311 static inline void led_trigger_remove(struct led_classdev
*led_cdev
) {}
312 static inline void *led_get_trigger_data(struct led_classdev
*led_cdev
)
317 #endif /* CONFIG_LEDS_TRIGGERS */
319 /* Trigger specific functions */
320 #ifdef CONFIG_LEDS_TRIGGER_IDE_DISK
321 extern void ledtrig_ide_activity(void);
323 static inline void ledtrig_ide_activity(void) {}
326 #if defined(CONFIG_LEDS_TRIGGER_CAMERA) || defined(CONFIG_LEDS_TRIGGER_CAMERA_MODULE)
327 extern void ledtrig_flash_ctrl(bool on
);
328 extern void ledtrig_torch_ctrl(bool on
);
330 static inline void ledtrig_flash_ctrl(bool on
) {}
331 static inline void ledtrig_torch_ctrl(bool on
) {}
335 * Generic LED platform data for describing LED names and default triggers.
339 const char *default_trigger
;
343 struct led_platform_data
{
345 struct led_info
*leds
;
348 /* For the leds-gpio driver */
351 const char *default_trigger
;
353 unsigned active_low
: 1;
354 unsigned retain_state_suspended
: 1;
355 unsigned default_state
: 2;
356 /* default_state should be one of LEDS_GPIO_DEFSTATE_(ON|OFF|KEEP) */
357 struct gpio_desc
*gpiod
;
359 #define LEDS_GPIO_DEFSTATE_OFF 0
360 #define LEDS_GPIO_DEFSTATE_ON 1
361 #define LEDS_GPIO_DEFSTATE_KEEP 2
363 struct gpio_led_platform_data
{
365 const struct gpio_led
*leds
;
367 #define GPIO_LED_NO_BLINK_LOW 0 /* No blink GPIO state low */
368 #define GPIO_LED_NO_BLINK_HIGH 1 /* No blink GPIO state high */
369 #define GPIO_LED_BLINK 2 /* Please, blink */
370 int (*gpio_blink_set
)(struct gpio_desc
*desc
, int state
,
371 unsigned long *delay_on
,
372 unsigned long *delay_off
);
375 struct platform_device
*gpio_led_register_device(
376 int id
, const struct gpio_led_platform_data
*pdata
);
379 CPU_LED_IDLE_START
, /* CPU enters idle */
380 CPU_LED_IDLE_END
, /* CPU idle ends */
381 CPU_LED_START
, /* Machine starts, especially resume */
382 CPU_LED_STOP
, /* Machine stops, especially suspend */
383 CPU_LED_HALTED
, /* Machine shutdown */
385 #ifdef CONFIG_LEDS_TRIGGER_CPU
386 extern void ledtrig_cpu(enum cpu_led_event evt
);
388 static inline void ledtrig_cpu(enum cpu_led_event evt
)
394 #endif /* __LINUX_LEDS_H_INCLUDED */