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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * LED Triggers Core
4 *
5 * Copyright 2005-2007 Openedhand Ltd.
6 *
7 * Author: Richard Purdie <rpurdie@openedhand.com>
8 */
9
10#include <linux/export.h>
11#include <linux/kernel.h>
12#include <linux/list.h>
13#include <linux/spinlock.h>
14#include <linux/device.h>
15#include <linux/timer.h>
16#include <linux/rwsem.h>
17#include <linux/leds.h>
18#include <linux/slab.h>
19#include <linux/mm.h>
20#include "leds.h"
21
22/*
23 * Nests outside led_cdev->trigger_lock
24 */
25static DECLARE_RWSEM(triggers_list_lock);
26LIST_HEAD(trigger_list);
27
28 /* Used by LED Class */
29
30static inline bool
31trigger_relevant(struct led_classdev *led_cdev, struct led_trigger *trig)
32{
33 return !trig->trigger_type || trig->trigger_type == led_cdev->trigger_type;
34}
35
36ssize_t led_trigger_write(struct file *filp, struct kobject *kobj,
37 struct bin_attribute *bin_attr, char *buf,
38 loff_t pos, size_t count)
39{
40 struct device *dev = kobj_to_dev(kobj);
41 struct led_classdev *led_cdev = dev_get_drvdata(dev);
42 struct led_trigger *trig;
43 int ret = count;
44
45 mutex_lock(&led_cdev->led_access);
46
47 if (led_sysfs_is_disabled(led_cdev)) {
48 ret = -EBUSY;
49 goto unlock;
50 }
51
52 if (sysfs_streq(buf, "none")) {
53 led_trigger_remove(led_cdev);
54 goto unlock;
55 }
56
57 down_read(&triggers_list_lock);
58 list_for_each_entry(trig, &trigger_list, next_trig) {
59 if (sysfs_streq(buf, trig->name) && trigger_relevant(led_cdev, trig)) {
60 down_write(&led_cdev->trigger_lock);
61 led_trigger_set(led_cdev, trig);
62 up_write(&led_cdev->trigger_lock);
63
64 up_read(&triggers_list_lock);
65 goto unlock;
66 }
67 }
68 /* we come here only if buf matches no trigger */
69 ret = -EINVAL;
70 up_read(&triggers_list_lock);
71
72unlock:
73 mutex_unlock(&led_cdev->led_access);
74 return ret;
75}
76EXPORT_SYMBOL_GPL(led_trigger_write);
77
78__printf(3, 4)
79static int led_trigger_snprintf(char *buf, ssize_t size, const char *fmt, ...)
80{
81 va_list args;
82 int i;
83
84 va_start(args, fmt);
85 if (size <= 0)
86 i = vsnprintf(NULL, 0, fmt, args);
87 else
88 i = vscnprintf(buf, size, fmt, args);
89 va_end(args);
90
91 return i;
92}
93
94static int led_trigger_format(char *buf, size_t size,
95 struct led_classdev *led_cdev)
96{
97 struct led_trigger *trig;
98 int len = led_trigger_snprintf(buf, size, "%s",
99 led_cdev->trigger ? "none" : "[none]");
100
101 list_for_each_entry(trig, &trigger_list, next_trig) {
102 bool hit;
103
104 if (!trigger_relevant(led_cdev, trig))
105 continue;
106
107 hit = led_cdev->trigger && !strcmp(led_cdev->trigger->name, trig->name);
108
109 len += led_trigger_snprintf(buf + len, size - len,
110 " %s%s%s", hit ? "[" : "",
111 trig->name, hit ? "]" : "");
112 }
113
114 len += led_trigger_snprintf(buf + len, size - len, "\n");
115
116 return len;
117}
118
119/*
120 * It was stupid to create 10000 cpu triggers, but we are stuck with it now.
121 * Don't make that mistake again. We work around it here by creating binary
122 * attribute, which is not limited by length. This is _not_ good design, do not
123 * copy it.
124 */
125ssize_t led_trigger_read(struct file *filp, struct kobject *kobj,
126 struct bin_attribute *attr, char *buf,
127 loff_t pos, size_t count)
128{
129 struct device *dev = kobj_to_dev(kobj);
130 struct led_classdev *led_cdev = dev_get_drvdata(dev);
131 void *data;
132 int len;
133
134 down_read(&triggers_list_lock);
135 down_read(&led_cdev->trigger_lock);
136
137 len = led_trigger_format(NULL, 0, led_cdev);
138 data = kvmalloc(len + 1, GFP_KERNEL);
139 if (!data) {
140 up_read(&led_cdev->trigger_lock);
141 up_read(&triggers_list_lock);
142 return -ENOMEM;
143 }
144 len = led_trigger_format(data, len + 1, led_cdev);
145
146 up_read(&led_cdev->trigger_lock);
147 up_read(&triggers_list_lock);
148
149 len = memory_read_from_buffer(buf, count, &pos, data, len);
150
151 kvfree(data);
152
153 return len;
154}
155EXPORT_SYMBOL_GPL(led_trigger_read);
156
157/* Caller must ensure led_cdev->trigger_lock held */
158int led_trigger_set(struct led_classdev *led_cdev, struct led_trigger *trig)
159{
160 char *event = NULL;
161 char *envp[2];
162 const char *name;
163 int ret;
164
165 if (!led_cdev->trigger && !trig)
166 return 0;
167
168 name = trig ? trig->name : "none";
169 event = kasprintf(GFP_KERNEL, "TRIGGER=%s", name);
170
171 /* Remove any existing trigger */
172 if (led_cdev->trigger) {
173 spin_lock(&led_cdev->trigger->leddev_list_lock);
174 list_del_rcu(&led_cdev->trig_list);
175 spin_unlock(&led_cdev->trigger->leddev_list_lock);
176
177 /* ensure it's no longer visible on the led_cdevs list */
178 synchronize_rcu();
179
180 cancel_work_sync(&led_cdev->set_brightness_work);
181 led_stop_software_blink(led_cdev);
182 if (led_cdev->trigger->deactivate)
183 led_cdev->trigger->deactivate(led_cdev);
184 device_remove_groups(led_cdev->dev, led_cdev->trigger->groups);
185 led_cdev->trigger = NULL;
186 led_cdev->trigger_data = NULL;
187 led_cdev->activated = false;
188 led_set_brightness(led_cdev, LED_OFF);
189 }
190 if (trig) {
191 spin_lock(&trig->leddev_list_lock);
192 list_add_tail_rcu(&led_cdev->trig_list, &trig->led_cdevs);
193 spin_unlock(&trig->leddev_list_lock);
194 led_cdev->trigger = trig;
195
196 if (trig->activate)
197 ret = trig->activate(led_cdev);
198 else
199 ret = 0;
200
201 if (ret)
202 goto err_activate;
203
204 ret = device_add_groups(led_cdev->dev, trig->groups);
205 if (ret) {
206 dev_err(led_cdev->dev, "Failed to add trigger attributes\n");
207 goto err_add_groups;
208 }
209 }
210
211 if (event) {
212 envp[0] = event;
213 envp[1] = NULL;
214 if (kobject_uevent_env(&led_cdev->dev->kobj, KOBJ_CHANGE, envp))
215 dev_err(led_cdev->dev,
216 "%s: Error sending uevent\n", __func__);
217 kfree(event);
218 }
219
220 return 0;
221
222err_add_groups:
223
224 if (trig->deactivate)
225 trig->deactivate(led_cdev);
226err_activate:
227
228 spin_lock(&led_cdev->trigger->leddev_list_lock);
229 list_del_rcu(&led_cdev->trig_list);
230 spin_unlock(&led_cdev->trigger->leddev_list_lock);
231 synchronize_rcu();
232 led_cdev->trigger = NULL;
233 led_cdev->trigger_data = NULL;
234 led_set_brightness(led_cdev, LED_OFF);
235 kfree(event);
236
237 return ret;
238}
239EXPORT_SYMBOL_GPL(led_trigger_set);
240
241void led_trigger_remove(struct led_classdev *led_cdev)
242{
243 down_write(&led_cdev->trigger_lock);
244 led_trigger_set(led_cdev, NULL);
245 up_write(&led_cdev->trigger_lock);
246}
247EXPORT_SYMBOL_GPL(led_trigger_remove);
248
249void led_trigger_set_default(struct led_classdev *led_cdev)
250{
251 struct led_trigger *trig;
252
253 if (!led_cdev->default_trigger)
254 return;
255
256 down_read(&triggers_list_lock);
257 down_write(&led_cdev->trigger_lock);
258 list_for_each_entry(trig, &trigger_list, next_trig) {
259 if (!strcmp(led_cdev->default_trigger, trig->name) &&
260 trigger_relevant(led_cdev, trig)) {
261 led_cdev->flags |= LED_INIT_DEFAULT_TRIGGER;
262 led_trigger_set(led_cdev, trig);
263 break;
264 }
265 }
266 up_write(&led_cdev->trigger_lock);
267 up_read(&triggers_list_lock);
268}
269EXPORT_SYMBOL_GPL(led_trigger_set_default);
270
271void led_trigger_rename_static(const char *name, struct led_trigger *trig)
272{
273 /* new name must be on a temporary string to prevent races */
274 BUG_ON(name == trig->name);
275
276 down_write(&triggers_list_lock);
277 /* this assumes that trig->name was originaly allocated to
278 * non constant storage */
279 strcpy((char *)trig->name, name);
280 up_write(&triggers_list_lock);
281}
282EXPORT_SYMBOL_GPL(led_trigger_rename_static);
283
284/* LED Trigger Interface */
285
286int led_trigger_register(struct led_trigger *trig)
287{
288 struct led_classdev *led_cdev;
289 struct led_trigger *_trig;
290
291 spin_lock_init(&trig->leddev_list_lock);
292 INIT_LIST_HEAD(&trig->led_cdevs);
293
294 down_write(&triggers_list_lock);
295 /* Make sure the trigger's name isn't already in use */
296 list_for_each_entry(_trig, &trigger_list, next_trig) {
297 if (!strcmp(_trig->name, trig->name) &&
298 (trig->trigger_type == _trig->trigger_type ||
299 !trig->trigger_type || !_trig->trigger_type)) {
300 up_write(&triggers_list_lock);
301 return -EEXIST;
302 }
303 }
304 /* Add to the list of led triggers */
305 list_add_tail(&trig->next_trig, &trigger_list);
306 up_write(&triggers_list_lock);
307
308 /* Register with any LEDs that have this as a default trigger */
309 down_read(&leds_list_lock);
310 list_for_each_entry(led_cdev, &leds_list, node) {
311 down_write(&led_cdev->trigger_lock);
312 if (!led_cdev->trigger && led_cdev->default_trigger &&
313 !strcmp(led_cdev->default_trigger, trig->name) &&
314 trigger_relevant(led_cdev, trig)) {
315 led_cdev->flags |= LED_INIT_DEFAULT_TRIGGER;
316 led_trigger_set(led_cdev, trig);
317 }
318 up_write(&led_cdev->trigger_lock);
319 }
320 up_read(&leds_list_lock);
321
322 return 0;
323}
324EXPORT_SYMBOL_GPL(led_trigger_register);
325
326void led_trigger_unregister(struct led_trigger *trig)
327{
328 struct led_classdev *led_cdev;
329
330 if (list_empty_careful(&trig->next_trig))
331 return;
332
333 /* Remove from the list of led triggers */
334 down_write(&triggers_list_lock);
335 list_del_init(&trig->next_trig);
336 up_write(&triggers_list_lock);
337
338 /* Remove anyone actively using this trigger */
339 down_read(&leds_list_lock);
340 list_for_each_entry(led_cdev, &leds_list, node) {
341 down_write(&led_cdev->trigger_lock);
342 if (led_cdev->trigger == trig)
343 led_trigger_set(led_cdev, NULL);
344 up_write(&led_cdev->trigger_lock);
345 }
346 up_read(&leds_list_lock);
347}
348EXPORT_SYMBOL_GPL(led_trigger_unregister);
349
350static void devm_led_trigger_release(struct device *dev, void *res)
351{
352 led_trigger_unregister(*(struct led_trigger **)res);
353}
354
355int devm_led_trigger_register(struct device *dev,
356 struct led_trigger *trig)
357{
358 struct led_trigger **dr;
359 int rc;
360
361 dr = devres_alloc(devm_led_trigger_release, sizeof(*dr),
362 GFP_KERNEL);
363 if (!dr)
364 return -ENOMEM;
365
366 *dr = trig;
367
368 rc = led_trigger_register(trig);
369 if (rc)
370 devres_free(dr);
371 else
372 devres_add(dev, dr);
373
374 return rc;
375}
376EXPORT_SYMBOL_GPL(devm_led_trigger_register);
377
378/* Simple LED Trigger Interface */
379
380void led_trigger_event(struct led_trigger *trig,
381 enum led_brightness brightness)
382{
383 struct led_classdev *led_cdev;
384
385 if (!trig)
386 return;
387
388 rcu_read_lock();
389 list_for_each_entry_rcu(led_cdev, &trig->led_cdevs, trig_list)
390 led_set_brightness(led_cdev, brightness);
391 rcu_read_unlock();
392}
393EXPORT_SYMBOL_GPL(led_trigger_event);
394
395static void led_trigger_blink_setup(struct led_trigger *trig,
396 unsigned long *delay_on,
397 unsigned long *delay_off,
398 int oneshot,
399 int invert)
400{
401 struct led_classdev *led_cdev;
402
403 if (!trig)
404 return;
405
406 rcu_read_lock();
407 list_for_each_entry_rcu(led_cdev, &trig->led_cdevs, trig_list) {
408 if (oneshot)
409 led_blink_set_oneshot(led_cdev, delay_on, delay_off,
410 invert);
411 else
412 led_blink_set(led_cdev, delay_on, delay_off);
413 }
414 rcu_read_unlock();
415}
416
417void led_trigger_blink(struct led_trigger *trig,
418 unsigned long *delay_on,
419 unsigned long *delay_off)
420{
421 led_trigger_blink_setup(trig, delay_on, delay_off, 0, 0);
422}
423EXPORT_SYMBOL_GPL(led_trigger_blink);
424
425void led_trigger_blink_oneshot(struct led_trigger *trig,
426 unsigned long *delay_on,
427 unsigned long *delay_off,
428 int invert)
429{
430 led_trigger_blink_setup(trig, delay_on, delay_off, 1, invert);
431}
432EXPORT_SYMBOL_GPL(led_trigger_blink_oneshot);
433
434void led_trigger_register_simple(const char *name, struct led_trigger **tp)
435{
436 struct led_trigger *trig;
437 int err;
438
439 trig = kzalloc(sizeof(struct led_trigger), GFP_KERNEL);
440
441 if (trig) {
442 trig->name = name;
443 err = led_trigger_register(trig);
444 if (err < 0) {
445 kfree(trig);
446 trig = NULL;
447 pr_warn("LED trigger %s failed to register (%d)\n",
448 name, err);
449 }
450 } else {
451 pr_warn("LED trigger %s failed to register (no memory)\n",
452 name);
453 }
454 *tp = trig;
455}
456EXPORT_SYMBOL_GPL(led_trigger_register_simple);
457
458void led_trigger_unregister_simple(struct led_trigger *trig)
459{
460 if (trig)
461 led_trigger_unregister(trig);
462 kfree(trig);
463}
464EXPORT_SYMBOL_GPL(led_trigger_unregister_simple);
1/*
2 * LED Triggers Core
3 *
4 * Copyright 2005-2007 Openedhand Ltd.
5 *
6 * Author: Richard Purdie <rpurdie@openedhand.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 *
12 */
13
14#include <linux/module.h>
15#include <linux/kernel.h>
16#include <linux/init.h>
17#include <linux/list.h>
18#include <linux/spinlock.h>
19#include <linux/device.h>
20#include <linux/sysdev.h>
21#include <linux/timer.h>
22#include <linux/rwsem.h>
23#include <linux/leds.h>
24#include <linux/slab.h>
25#include "leds.h"
26
27/*
28 * Nests outside led_cdev->trigger_lock
29 */
30static DECLARE_RWSEM(triggers_list_lock);
31static LIST_HEAD(trigger_list);
32
33 /* Used by LED Class */
34
35ssize_t led_trigger_store(struct device *dev, struct device_attribute *attr,
36 const char *buf, size_t count)
37{
38 struct led_classdev *led_cdev = dev_get_drvdata(dev);
39 char trigger_name[TRIG_NAME_MAX];
40 struct led_trigger *trig;
41 size_t len;
42
43 trigger_name[sizeof(trigger_name) - 1] = '\0';
44 strncpy(trigger_name, buf, sizeof(trigger_name) - 1);
45 len = strlen(trigger_name);
46
47 if (len && trigger_name[len - 1] == '\n')
48 trigger_name[len - 1] = '\0';
49
50 if (!strcmp(trigger_name, "none")) {
51 led_trigger_remove(led_cdev);
52 return count;
53 }
54
55 down_read(&triggers_list_lock);
56 list_for_each_entry(trig, &trigger_list, next_trig) {
57 if (!strcmp(trigger_name, trig->name)) {
58 down_write(&led_cdev->trigger_lock);
59 led_trigger_set(led_cdev, trig);
60 up_write(&led_cdev->trigger_lock);
61
62 up_read(&triggers_list_lock);
63 return count;
64 }
65 }
66 up_read(&triggers_list_lock);
67
68 return -EINVAL;
69}
70EXPORT_SYMBOL_GPL(led_trigger_store);
71
72ssize_t led_trigger_show(struct device *dev, struct device_attribute *attr,
73 char *buf)
74{
75 struct led_classdev *led_cdev = dev_get_drvdata(dev);
76 struct led_trigger *trig;
77 int len = 0;
78
79 down_read(&triggers_list_lock);
80 down_read(&led_cdev->trigger_lock);
81
82 if (!led_cdev->trigger)
83 len += sprintf(buf+len, "[none] ");
84 else
85 len += sprintf(buf+len, "none ");
86
87 list_for_each_entry(trig, &trigger_list, next_trig) {
88 if (led_cdev->trigger && !strcmp(led_cdev->trigger->name,
89 trig->name))
90 len += sprintf(buf+len, "[%s] ", trig->name);
91 else
92 len += sprintf(buf+len, "%s ", trig->name);
93 }
94 up_read(&led_cdev->trigger_lock);
95 up_read(&triggers_list_lock);
96
97 len += sprintf(len+buf, "\n");
98 return len;
99}
100EXPORT_SYMBOL_GPL(led_trigger_show);
101
102/* Caller must ensure led_cdev->trigger_lock held */
103void led_trigger_set(struct led_classdev *led_cdev, struct led_trigger *trigger)
104{
105 unsigned long flags;
106
107 /* Remove any existing trigger */
108 if (led_cdev->trigger) {
109 write_lock_irqsave(&led_cdev->trigger->leddev_list_lock, flags);
110 list_del(&led_cdev->trig_list);
111 write_unlock_irqrestore(&led_cdev->trigger->leddev_list_lock,
112 flags);
113 if (led_cdev->trigger->deactivate)
114 led_cdev->trigger->deactivate(led_cdev);
115 led_cdev->trigger = NULL;
116 led_brightness_set(led_cdev, LED_OFF);
117 }
118 if (trigger) {
119 write_lock_irqsave(&trigger->leddev_list_lock, flags);
120 list_add_tail(&led_cdev->trig_list, &trigger->led_cdevs);
121 write_unlock_irqrestore(&trigger->leddev_list_lock, flags);
122 led_cdev->trigger = trigger;
123 if (trigger->activate)
124 trigger->activate(led_cdev);
125 }
126}
127EXPORT_SYMBOL_GPL(led_trigger_set);
128
129void led_trigger_remove(struct led_classdev *led_cdev)
130{
131 down_write(&led_cdev->trigger_lock);
132 led_trigger_set(led_cdev, NULL);
133 up_write(&led_cdev->trigger_lock);
134}
135EXPORT_SYMBOL_GPL(led_trigger_remove);
136
137void led_trigger_set_default(struct led_classdev *led_cdev)
138{
139 struct led_trigger *trig;
140
141 if (!led_cdev->default_trigger)
142 return;
143
144 down_read(&triggers_list_lock);
145 down_write(&led_cdev->trigger_lock);
146 list_for_each_entry(trig, &trigger_list, next_trig) {
147 if (!strcmp(led_cdev->default_trigger, trig->name))
148 led_trigger_set(led_cdev, trig);
149 }
150 up_write(&led_cdev->trigger_lock);
151 up_read(&triggers_list_lock);
152}
153EXPORT_SYMBOL_GPL(led_trigger_set_default);
154
155/* LED Trigger Interface */
156
157int led_trigger_register(struct led_trigger *trigger)
158{
159 struct led_classdev *led_cdev;
160 struct led_trigger *trig;
161
162 rwlock_init(&trigger->leddev_list_lock);
163 INIT_LIST_HEAD(&trigger->led_cdevs);
164
165 down_write(&triggers_list_lock);
166 /* Make sure the trigger's name isn't already in use */
167 list_for_each_entry(trig, &trigger_list, next_trig) {
168 if (!strcmp(trig->name, trigger->name)) {
169 up_write(&triggers_list_lock);
170 return -EEXIST;
171 }
172 }
173 /* Add to the list of led triggers */
174 list_add_tail(&trigger->next_trig, &trigger_list);
175 up_write(&triggers_list_lock);
176
177 /* Register with any LEDs that have this as a default trigger */
178 down_read(&leds_list_lock);
179 list_for_each_entry(led_cdev, &leds_list, node) {
180 down_write(&led_cdev->trigger_lock);
181 if (!led_cdev->trigger && led_cdev->default_trigger &&
182 !strcmp(led_cdev->default_trigger, trigger->name))
183 led_trigger_set(led_cdev, trigger);
184 up_write(&led_cdev->trigger_lock);
185 }
186 up_read(&leds_list_lock);
187
188 return 0;
189}
190EXPORT_SYMBOL_GPL(led_trigger_register);
191
192void led_trigger_unregister(struct led_trigger *trigger)
193{
194 struct led_classdev *led_cdev;
195
196 /* Remove from the list of led triggers */
197 down_write(&triggers_list_lock);
198 list_del(&trigger->next_trig);
199 up_write(&triggers_list_lock);
200
201 /* Remove anyone actively using this trigger */
202 down_read(&leds_list_lock);
203 list_for_each_entry(led_cdev, &leds_list, node) {
204 down_write(&led_cdev->trigger_lock);
205 if (led_cdev->trigger == trigger)
206 led_trigger_set(led_cdev, NULL);
207 up_write(&led_cdev->trigger_lock);
208 }
209 up_read(&leds_list_lock);
210}
211EXPORT_SYMBOL_GPL(led_trigger_unregister);
212
213/* Simple LED Tigger Interface */
214
215void led_trigger_event(struct led_trigger *trigger,
216 enum led_brightness brightness)
217{
218 struct list_head *entry;
219
220 if (!trigger)
221 return;
222
223 read_lock(&trigger->leddev_list_lock);
224 list_for_each(entry, &trigger->led_cdevs) {
225 struct led_classdev *led_cdev;
226
227 led_cdev = list_entry(entry, struct led_classdev, trig_list);
228 led_set_brightness(led_cdev, brightness);
229 }
230 read_unlock(&trigger->leddev_list_lock);
231}
232EXPORT_SYMBOL_GPL(led_trigger_event);
233
234void led_trigger_blink(struct led_trigger *trigger,
235 unsigned long *delay_on,
236 unsigned long *delay_off)
237{
238 struct list_head *entry;
239
240 if (!trigger)
241 return;
242
243 read_lock(&trigger->leddev_list_lock);
244 list_for_each(entry, &trigger->led_cdevs) {
245 struct led_classdev *led_cdev;
246
247 led_cdev = list_entry(entry, struct led_classdev, trig_list);
248 led_blink_set(led_cdev, delay_on, delay_off);
249 }
250 read_unlock(&trigger->leddev_list_lock);
251}
252EXPORT_SYMBOL_GPL(led_trigger_blink);
253
254void led_trigger_register_simple(const char *name, struct led_trigger **tp)
255{
256 struct led_trigger *trigger;
257 int err;
258
259 trigger = kzalloc(sizeof(struct led_trigger), GFP_KERNEL);
260
261 if (trigger) {
262 trigger->name = name;
263 err = led_trigger_register(trigger);
264 if (err < 0)
265 printk(KERN_WARNING "LED trigger %s failed to register"
266 " (%d)\n", name, err);
267 } else
268 printk(KERN_WARNING "LED trigger %s failed to register"
269 " (no memory)\n", name);
270
271 *tp = trigger;
272}
273EXPORT_SYMBOL_GPL(led_trigger_register_simple);
274
275void led_trigger_unregister_simple(struct led_trigger *trigger)
276{
277 if (trigger)
278 led_trigger_unregister(trigger);
279 kfree(trigger);
280}
281EXPORT_SYMBOL_GPL(led_trigger_unregister_simple);
282
283MODULE_AUTHOR("Richard Purdie");
284MODULE_LICENSE("GPL");
285MODULE_DESCRIPTION("LED Triggers Core");