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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);
26static LIST_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 device_remove_groups(led_cdev->dev, led_cdev->trigger->groups);
183 if (led_cdev->trigger->deactivate)
184 led_cdev->trigger->deactivate(led_cdev);
185 led_cdev->trigger = NULL;
186 led_cdev->trigger_data = NULL;
187 led_cdev->activated = false;
188 led_cdev->flags &= ~LED_INIT_DEFAULT_TRIGGER;
189 led_set_brightness(led_cdev, LED_OFF);
190 }
191 if (trig) {
192 spin_lock(&trig->leddev_list_lock);
193 list_add_tail_rcu(&led_cdev->trig_list, &trig->led_cdevs);
194 spin_unlock(&trig->leddev_list_lock);
195 led_cdev->trigger = trig;
196
197 /*
198 * Some activate() calls use led_trigger_event() to initialize
199 * the brightness of the LED for which the trigger is being set.
200 * Ensure the led_cdev is visible on trig->led_cdevs for this.
201 */
202 synchronize_rcu();
203
204 /*
205 * If "set brightness to 0" is pending in workqueue,
206 * we don't want that to be reordered after ->activate()
207 */
208 flush_work(&led_cdev->set_brightness_work);
209
210 ret = 0;
211 if (trig->activate)
212 ret = trig->activate(led_cdev);
213 else
214 led_set_brightness(led_cdev, trig->brightness);
215 if (ret)
216 goto err_activate;
217
218 ret = device_add_groups(led_cdev->dev, trig->groups);
219 if (ret) {
220 dev_err(led_cdev->dev, "Failed to add trigger attributes\n");
221 goto err_add_groups;
222 }
223 }
224
225 if (event) {
226 envp[0] = event;
227 envp[1] = NULL;
228 if (kobject_uevent_env(&led_cdev->dev->kobj, KOBJ_CHANGE, envp))
229 dev_err(led_cdev->dev,
230 "%s: Error sending uevent\n", __func__);
231 kfree(event);
232 }
233
234 return 0;
235
236err_add_groups:
237
238 if (trig->deactivate)
239 trig->deactivate(led_cdev);
240err_activate:
241
242 spin_lock(&led_cdev->trigger->leddev_list_lock);
243 list_del_rcu(&led_cdev->trig_list);
244 spin_unlock(&led_cdev->trigger->leddev_list_lock);
245 synchronize_rcu();
246 led_cdev->trigger = NULL;
247 led_cdev->trigger_data = NULL;
248 led_set_brightness(led_cdev, LED_OFF);
249 kfree(event);
250
251 return ret;
252}
253EXPORT_SYMBOL_GPL(led_trigger_set);
254
255void led_trigger_remove(struct led_classdev *led_cdev)
256{
257 down_write(&led_cdev->trigger_lock);
258 led_trigger_set(led_cdev, NULL);
259 up_write(&led_cdev->trigger_lock);
260}
261EXPORT_SYMBOL_GPL(led_trigger_remove);
262
263static bool led_match_default_trigger(struct led_classdev *led_cdev,
264 struct led_trigger *trig)
265{
266 if (!strcmp(led_cdev->default_trigger, trig->name) &&
267 trigger_relevant(led_cdev, trig)) {
268 led_cdev->flags |= LED_INIT_DEFAULT_TRIGGER;
269 led_trigger_set(led_cdev, trig);
270 return true;
271 }
272
273 return false;
274}
275
276void led_trigger_set_default(struct led_classdev *led_cdev)
277{
278 struct led_trigger *trig;
279 bool found = false;
280
281 if (!led_cdev->default_trigger)
282 return;
283
284 down_read(&triggers_list_lock);
285 down_write(&led_cdev->trigger_lock);
286 list_for_each_entry(trig, &trigger_list, next_trig) {
287 found = led_match_default_trigger(led_cdev, trig);
288 if (found)
289 break;
290 }
291 up_write(&led_cdev->trigger_lock);
292 up_read(&triggers_list_lock);
293
294 /*
295 * If default trigger wasn't found, maybe trigger module isn't loaded yet.
296 * Once loaded it will re-probe with all led_cdev's.
297 */
298 if (!found)
299 request_module_nowait("ledtrig:%s", led_cdev->default_trigger);
300}
301EXPORT_SYMBOL_GPL(led_trigger_set_default);
302
303/* LED Trigger Interface */
304
305int led_trigger_register(struct led_trigger *trig)
306{
307 struct led_classdev *led_cdev;
308 struct led_trigger *_trig;
309
310 spin_lock_init(&trig->leddev_list_lock);
311 INIT_LIST_HEAD(&trig->led_cdevs);
312
313 down_write(&triggers_list_lock);
314 /* Make sure the trigger's name isn't already in use */
315 list_for_each_entry(_trig, &trigger_list, next_trig) {
316 if (!strcmp(_trig->name, trig->name) &&
317 (trig->trigger_type == _trig->trigger_type ||
318 !trig->trigger_type || !_trig->trigger_type)) {
319 up_write(&triggers_list_lock);
320 return -EEXIST;
321 }
322 }
323 /* Add to the list of led triggers */
324 list_add_tail(&trig->next_trig, &trigger_list);
325 up_write(&triggers_list_lock);
326
327 /* Register with any LEDs that have this as a default trigger */
328 down_read(&leds_list_lock);
329 list_for_each_entry(led_cdev, &leds_list, node) {
330 down_write(&led_cdev->trigger_lock);
331 if (!led_cdev->trigger && led_cdev->default_trigger)
332 led_match_default_trigger(led_cdev, trig);
333 up_write(&led_cdev->trigger_lock);
334 }
335 up_read(&leds_list_lock);
336
337 return 0;
338}
339EXPORT_SYMBOL_GPL(led_trigger_register);
340
341void led_trigger_unregister(struct led_trigger *trig)
342{
343 struct led_classdev *led_cdev;
344
345 if (list_empty_careful(&trig->next_trig))
346 return;
347
348 /* Remove from the list of led triggers */
349 down_write(&triggers_list_lock);
350 list_del_init(&trig->next_trig);
351 up_write(&triggers_list_lock);
352
353 /* Remove anyone actively using this trigger */
354 down_read(&leds_list_lock);
355 list_for_each_entry(led_cdev, &leds_list, node) {
356 down_write(&led_cdev->trigger_lock);
357 if (led_cdev->trigger == trig)
358 led_trigger_set(led_cdev, NULL);
359 up_write(&led_cdev->trigger_lock);
360 }
361 up_read(&leds_list_lock);
362}
363EXPORT_SYMBOL_GPL(led_trigger_unregister);
364
365static void devm_led_trigger_release(struct device *dev, void *res)
366{
367 led_trigger_unregister(*(struct led_trigger **)res);
368}
369
370int devm_led_trigger_register(struct device *dev,
371 struct led_trigger *trig)
372{
373 struct led_trigger **dr;
374 int rc;
375
376 dr = devres_alloc(devm_led_trigger_release, sizeof(*dr),
377 GFP_KERNEL);
378 if (!dr)
379 return -ENOMEM;
380
381 *dr = trig;
382
383 rc = led_trigger_register(trig);
384 if (rc)
385 devres_free(dr);
386 else
387 devres_add(dev, dr);
388
389 return rc;
390}
391EXPORT_SYMBOL_GPL(devm_led_trigger_register);
392
393/* Simple LED Trigger Interface */
394
395void led_trigger_event(struct led_trigger *trig,
396 enum led_brightness brightness)
397{
398 struct led_classdev *led_cdev;
399
400 if (!trig)
401 return;
402
403 trig->brightness = brightness;
404
405 rcu_read_lock();
406 list_for_each_entry_rcu(led_cdev, &trig->led_cdevs, trig_list)
407 led_set_brightness(led_cdev, brightness);
408 rcu_read_unlock();
409}
410EXPORT_SYMBOL_GPL(led_trigger_event);
411
412void led_mc_trigger_event(struct led_trigger *trig,
413 unsigned int *intensity_value, unsigned int num_colors,
414 enum led_brightness brightness)
415{
416 struct led_classdev *led_cdev;
417
418 if (!trig)
419 return;
420
421 rcu_read_lock();
422 list_for_each_entry_rcu(led_cdev, &trig->led_cdevs, trig_list) {
423 if (!(led_cdev->flags & LED_MULTI_COLOR))
424 continue;
425
426 led_mc_set_brightness(led_cdev, intensity_value, num_colors, brightness);
427 }
428 rcu_read_unlock();
429}
430EXPORT_SYMBOL_GPL(led_mc_trigger_event);
431
432static void led_trigger_blink_setup(struct led_trigger *trig,
433 unsigned long delay_on,
434 unsigned long delay_off,
435 int oneshot,
436 int invert)
437{
438 struct led_classdev *led_cdev;
439
440 if (!trig)
441 return;
442
443 rcu_read_lock();
444 list_for_each_entry_rcu(led_cdev, &trig->led_cdevs, trig_list) {
445 if (oneshot)
446 led_blink_set_oneshot(led_cdev, &delay_on, &delay_off,
447 invert);
448 else
449 led_blink_set_nosleep(led_cdev, delay_on, delay_off);
450 }
451 rcu_read_unlock();
452}
453
454void led_trigger_blink(struct led_trigger *trig,
455 unsigned long delay_on,
456 unsigned long delay_off)
457{
458 led_trigger_blink_setup(trig, delay_on, delay_off, 0, 0);
459}
460EXPORT_SYMBOL_GPL(led_trigger_blink);
461
462void led_trigger_blink_oneshot(struct led_trigger *trig,
463 unsigned long delay_on,
464 unsigned long delay_off,
465 int invert)
466{
467 led_trigger_blink_setup(trig, delay_on, delay_off, 1, invert);
468}
469EXPORT_SYMBOL_GPL(led_trigger_blink_oneshot);
470
471void led_trigger_register_simple(const char *name, struct led_trigger **tp)
472{
473 struct led_trigger *trig;
474 int err;
475
476 trig = kzalloc(sizeof(struct led_trigger), GFP_KERNEL);
477
478 if (trig) {
479 trig->name = name;
480 err = led_trigger_register(trig);
481 if (err < 0) {
482 kfree(trig);
483 trig = NULL;
484 pr_warn("LED trigger %s failed to register (%d)\n",
485 name, err);
486 }
487 } else {
488 pr_warn("LED trigger %s failed to register (no memory)\n",
489 name);
490 }
491 *tp = trig;
492}
493EXPORT_SYMBOL_GPL(led_trigger_register_simple);
494
495void led_trigger_unregister_simple(struct led_trigger *trig)
496{
497 if (trig)
498 led_trigger_unregister(trig);
499 kfree(trig);
500}
501EXPORT_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/export.h>
15#include <linux/kernel.h>
16#include <linux/list.h>
17#include <linux/spinlock.h>
18#include <linux/device.h>
19#include <linux/timer.h>
20#include <linux/rwsem.h>
21#include <linux/leds.h>
22#include <linux/slab.h>
23#include "leds.h"
24
25/*
26 * Nests outside led_cdev->trigger_lock
27 */
28static DECLARE_RWSEM(triggers_list_lock);
29LIST_HEAD(trigger_list);
30
31 /* Used by LED Class */
32
33ssize_t led_trigger_store(struct device *dev, struct device_attribute *attr,
34 const char *buf, size_t count)
35{
36 struct led_classdev *led_cdev = dev_get_drvdata(dev);
37 struct led_trigger *trig;
38 int ret = count;
39
40 mutex_lock(&led_cdev->led_access);
41
42 if (led_sysfs_is_disabled(led_cdev)) {
43 ret = -EBUSY;
44 goto unlock;
45 }
46
47 if (sysfs_streq(buf, "none")) {
48 led_trigger_remove(led_cdev);
49 goto unlock;
50 }
51
52 down_read(&triggers_list_lock);
53 list_for_each_entry(trig, &trigger_list, next_trig) {
54 if (sysfs_streq(buf, trig->name)) {
55 down_write(&led_cdev->trigger_lock);
56 led_trigger_set(led_cdev, trig);
57 up_write(&led_cdev->trigger_lock);
58
59 up_read(&triggers_list_lock);
60 goto unlock;
61 }
62 }
63 /* we come here only if buf matches no trigger */
64 ret = -EINVAL;
65 up_read(&triggers_list_lock);
66
67unlock:
68 mutex_unlock(&led_cdev->led_access);
69 return ret;
70}
71EXPORT_SYMBOL_GPL(led_trigger_store);
72
73ssize_t led_trigger_show(struct device *dev, struct device_attribute *attr,
74 char *buf)
75{
76 struct led_classdev *led_cdev = dev_get_drvdata(dev);
77 struct led_trigger *trig;
78 int len = 0;
79
80 down_read(&triggers_list_lock);
81 down_read(&led_cdev->trigger_lock);
82
83 if (!led_cdev->trigger)
84 len += scnprintf(buf+len, PAGE_SIZE - len, "[none] ");
85 else
86 len += scnprintf(buf+len, PAGE_SIZE - len, "none ");
87
88 list_for_each_entry(trig, &trigger_list, next_trig) {
89 if (led_cdev->trigger && !strcmp(led_cdev->trigger->name,
90 trig->name))
91 len += scnprintf(buf+len, PAGE_SIZE - len, "[%s] ",
92 trig->name);
93 else
94 len += scnprintf(buf+len, PAGE_SIZE - len, "%s ",
95 trig->name);
96 }
97 up_read(&led_cdev->trigger_lock);
98 up_read(&triggers_list_lock);
99
100 len += scnprintf(len+buf, PAGE_SIZE - len, "\n");
101 return len;
102}
103EXPORT_SYMBOL_GPL(led_trigger_show);
104
105/* Caller must ensure led_cdev->trigger_lock held */
106void led_trigger_set(struct led_classdev *led_cdev, struct led_trigger *trig)
107{
108 unsigned long flags;
109 char *event = NULL;
110 char *envp[2];
111 const char *name;
112
113 if (!led_cdev->trigger && !trig)
114 return;
115
116 name = trig ? trig->name : "none";
117 event = kasprintf(GFP_KERNEL, "TRIGGER=%s", name);
118
119 /* Remove any existing trigger */
120 if (led_cdev->trigger) {
121 write_lock_irqsave(&led_cdev->trigger->leddev_list_lock, flags);
122 list_del(&led_cdev->trig_list);
123 write_unlock_irqrestore(&led_cdev->trigger->leddev_list_lock,
124 flags);
125 cancel_work_sync(&led_cdev->set_brightness_work);
126 led_stop_software_blink(led_cdev);
127 if (led_cdev->trigger->deactivate)
128 led_cdev->trigger->deactivate(led_cdev);
129 led_cdev->trigger = NULL;
130 led_set_brightness(led_cdev, LED_OFF);
131 }
132 if (trig) {
133 write_lock_irqsave(&trig->leddev_list_lock, flags);
134 list_add_tail(&led_cdev->trig_list, &trig->led_cdevs);
135 write_unlock_irqrestore(&trig->leddev_list_lock, flags);
136 led_cdev->trigger = trig;
137 if (trig->activate)
138 trig->activate(led_cdev);
139 }
140
141 if (event) {
142 envp[0] = event;
143 envp[1] = NULL;
144 if (kobject_uevent_env(&led_cdev->dev->kobj, KOBJ_CHANGE, envp))
145 dev_err(led_cdev->dev,
146 "%s: Error sending uevent\n", __func__);
147 kfree(event);
148 }
149}
150EXPORT_SYMBOL_GPL(led_trigger_set);
151
152void led_trigger_remove(struct led_classdev *led_cdev)
153{
154 down_write(&led_cdev->trigger_lock);
155 led_trigger_set(led_cdev, NULL);
156 up_write(&led_cdev->trigger_lock);
157}
158EXPORT_SYMBOL_GPL(led_trigger_remove);
159
160void led_trigger_set_default(struct led_classdev *led_cdev)
161{
162 struct led_trigger *trig;
163
164 if (!led_cdev->default_trigger)
165 return;
166
167 down_read(&triggers_list_lock);
168 down_write(&led_cdev->trigger_lock);
169 list_for_each_entry(trig, &trigger_list, next_trig) {
170 if (!strcmp(led_cdev->default_trigger, trig->name))
171 led_trigger_set(led_cdev, trig);
172 }
173 up_write(&led_cdev->trigger_lock);
174 up_read(&triggers_list_lock);
175}
176EXPORT_SYMBOL_GPL(led_trigger_set_default);
177
178void led_trigger_rename_static(const char *name, struct led_trigger *trig)
179{
180 /* new name must be on a temporary string to prevent races */
181 BUG_ON(name == trig->name);
182
183 down_write(&triggers_list_lock);
184 /* this assumes that trig->name was originaly allocated to
185 * non constant storage */
186 strcpy((char *)trig->name, name);
187 up_write(&triggers_list_lock);
188}
189EXPORT_SYMBOL_GPL(led_trigger_rename_static);
190
191/* LED Trigger Interface */
192
193int led_trigger_register(struct led_trigger *trig)
194{
195 struct led_classdev *led_cdev;
196 struct led_trigger *_trig;
197
198 rwlock_init(&trig->leddev_list_lock);
199 INIT_LIST_HEAD(&trig->led_cdevs);
200
201 down_write(&triggers_list_lock);
202 /* Make sure the trigger's name isn't already in use */
203 list_for_each_entry(_trig, &trigger_list, next_trig) {
204 if (!strcmp(_trig->name, trig->name)) {
205 up_write(&triggers_list_lock);
206 return -EEXIST;
207 }
208 }
209 /* Add to the list of led triggers */
210 list_add_tail(&trig->next_trig, &trigger_list);
211 up_write(&triggers_list_lock);
212
213 /* Register with any LEDs that have this as a default trigger */
214 down_read(&leds_list_lock);
215 list_for_each_entry(led_cdev, &leds_list, node) {
216 down_write(&led_cdev->trigger_lock);
217 if (!led_cdev->trigger && led_cdev->default_trigger &&
218 !strcmp(led_cdev->default_trigger, trig->name))
219 led_trigger_set(led_cdev, trig);
220 up_write(&led_cdev->trigger_lock);
221 }
222 up_read(&leds_list_lock);
223
224 return 0;
225}
226EXPORT_SYMBOL_GPL(led_trigger_register);
227
228void led_trigger_unregister(struct led_trigger *trig)
229{
230 struct led_classdev *led_cdev;
231
232 if (list_empty_careful(&trig->next_trig))
233 return;
234
235 /* Remove from the list of led triggers */
236 down_write(&triggers_list_lock);
237 list_del_init(&trig->next_trig);
238 up_write(&triggers_list_lock);
239
240 /* Remove anyone actively using this trigger */
241 down_read(&leds_list_lock);
242 list_for_each_entry(led_cdev, &leds_list, node) {
243 down_write(&led_cdev->trigger_lock);
244 if (led_cdev->trigger == trig)
245 led_trigger_set(led_cdev, NULL);
246 up_write(&led_cdev->trigger_lock);
247 }
248 up_read(&leds_list_lock);
249}
250EXPORT_SYMBOL_GPL(led_trigger_unregister);
251
252static void devm_led_trigger_release(struct device *dev, void *res)
253{
254 led_trigger_unregister(*(struct led_trigger **)res);
255}
256
257int devm_led_trigger_register(struct device *dev,
258 struct led_trigger *trig)
259{
260 struct led_trigger **dr;
261 int rc;
262
263 dr = devres_alloc(devm_led_trigger_release, sizeof(*dr),
264 GFP_KERNEL);
265 if (!dr)
266 return -ENOMEM;
267
268 *dr = trig;
269
270 rc = led_trigger_register(trig);
271 if (rc)
272 devres_free(dr);
273 else
274 devres_add(dev, dr);
275
276 return rc;
277}
278EXPORT_SYMBOL_GPL(devm_led_trigger_register);
279
280/* Simple LED Tigger Interface */
281
282void led_trigger_event(struct led_trigger *trig,
283 enum led_brightness brightness)
284{
285 struct led_classdev *led_cdev;
286
287 if (!trig)
288 return;
289
290 read_lock(&trig->leddev_list_lock);
291 list_for_each_entry(led_cdev, &trig->led_cdevs, trig_list)
292 led_set_brightness(led_cdev, brightness);
293 read_unlock(&trig->leddev_list_lock);
294}
295EXPORT_SYMBOL_GPL(led_trigger_event);
296
297static void led_trigger_blink_setup(struct led_trigger *trig,
298 unsigned long *delay_on,
299 unsigned long *delay_off,
300 int oneshot,
301 int invert)
302{
303 struct led_classdev *led_cdev;
304
305 if (!trig)
306 return;
307
308 read_lock(&trig->leddev_list_lock);
309 list_for_each_entry(led_cdev, &trig->led_cdevs, trig_list) {
310 if (oneshot)
311 led_blink_set_oneshot(led_cdev, delay_on, delay_off,
312 invert);
313 else
314 led_blink_set(led_cdev, delay_on, delay_off);
315 }
316 read_unlock(&trig->leddev_list_lock);
317}
318
319void led_trigger_blink(struct led_trigger *trig,
320 unsigned long *delay_on,
321 unsigned long *delay_off)
322{
323 led_trigger_blink_setup(trig, delay_on, delay_off, 0, 0);
324}
325EXPORT_SYMBOL_GPL(led_trigger_blink);
326
327void led_trigger_blink_oneshot(struct led_trigger *trig,
328 unsigned long *delay_on,
329 unsigned long *delay_off,
330 int invert)
331{
332 led_trigger_blink_setup(trig, delay_on, delay_off, 1, invert);
333}
334EXPORT_SYMBOL_GPL(led_trigger_blink_oneshot);
335
336void led_trigger_register_simple(const char *name, struct led_trigger **tp)
337{
338 struct led_trigger *trig;
339 int err;
340
341 trig = kzalloc(sizeof(struct led_trigger), GFP_KERNEL);
342
343 if (trig) {
344 trig->name = name;
345 err = led_trigger_register(trig);
346 if (err < 0) {
347 kfree(trig);
348 trig = NULL;
349 pr_warn("LED trigger %s failed to register (%d)\n",
350 name, err);
351 }
352 } else {
353 pr_warn("LED trigger %s failed to register (no memory)\n",
354 name);
355 }
356 *tp = trig;
357}
358EXPORT_SYMBOL_GPL(led_trigger_register_simple);
359
360void led_trigger_unregister_simple(struct led_trigger *trig)
361{
362 if (trig)
363 led_trigger_unregister(trig);
364 kfree(trig);
365}
366EXPORT_SYMBOL_GPL(led_trigger_unregister_simple);