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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_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 if (trig->activate)
198 ret = trig->activate(led_cdev);
199 else
200 ret = 0;
201
202 if (ret)
203 goto err_activate;
204
205 ret = device_add_groups(led_cdev->dev, trig->groups);
206 if (ret) {
207 dev_err(led_cdev->dev, "Failed to add trigger attributes\n");
208 goto err_add_groups;
209 }
210 }
211
212 if (event) {
213 envp[0] = event;
214 envp[1] = NULL;
215 if (kobject_uevent_env(&led_cdev->dev->kobj, KOBJ_CHANGE, envp))
216 dev_err(led_cdev->dev,
217 "%s: Error sending uevent\n", __func__);
218 kfree(event);
219 }
220
221 return 0;
222
223err_add_groups:
224
225 if (trig->deactivate)
226 trig->deactivate(led_cdev);
227err_activate:
228
229 spin_lock(&led_cdev->trigger->leddev_list_lock);
230 list_del_rcu(&led_cdev->trig_list);
231 spin_unlock(&led_cdev->trigger->leddev_list_lock);
232 synchronize_rcu();
233 led_cdev->trigger = NULL;
234 led_cdev->trigger_data = NULL;
235 led_set_brightness(led_cdev, LED_OFF);
236 kfree(event);
237
238 return ret;
239}
240EXPORT_SYMBOL_GPL(led_trigger_set);
241
242void led_trigger_remove(struct led_classdev *led_cdev)
243{
244 down_write(&led_cdev->trigger_lock);
245 led_trigger_set(led_cdev, NULL);
246 up_write(&led_cdev->trigger_lock);
247}
248EXPORT_SYMBOL_GPL(led_trigger_remove);
249
250void led_trigger_set_default(struct led_classdev *led_cdev)
251{
252 struct led_trigger *trig;
253
254 if (!led_cdev->default_trigger)
255 return;
256
257 down_read(&triggers_list_lock);
258 down_write(&led_cdev->trigger_lock);
259 list_for_each_entry(trig, &trigger_list, next_trig) {
260 if (!strcmp(led_cdev->default_trigger, trig->name) &&
261 trigger_relevant(led_cdev, trig)) {
262 led_cdev->flags |= LED_INIT_DEFAULT_TRIGGER;
263 led_trigger_set(led_cdev, trig);
264 break;
265 }
266 }
267 up_write(&led_cdev->trigger_lock);
268 up_read(&triggers_list_lock);
269}
270EXPORT_SYMBOL_GPL(led_trigger_set_default);
271
272/* LED Trigger Interface */
273
274int led_trigger_register(struct led_trigger *trig)
275{
276 struct led_classdev *led_cdev;
277 struct led_trigger *_trig;
278
279 spin_lock_init(&trig->leddev_list_lock);
280 INIT_LIST_HEAD(&trig->led_cdevs);
281
282 down_write(&triggers_list_lock);
283 /* Make sure the trigger's name isn't already in use */
284 list_for_each_entry(_trig, &trigger_list, next_trig) {
285 if (!strcmp(_trig->name, trig->name) &&
286 (trig->trigger_type == _trig->trigger_type ||
287 !trig->trigger_type || !_trig->trigger_type)) {
288 up_write(&triggers_list_lock);
289 return -EEXIST;
290 }
291 }
292 /* Add to the list of led triggers */
293 list_add_tail(&trig->next_trig, &trigger_list);
294 up_write(&triggers_list_lock);
295
296 /* Register with any LEDs that have this as a default trigger */
297 down_read(&leds_list_lock);
298 list_for_each_entry(led_cdev, &leds_list, node) {
299 down_write(&led_cdev->trigger_lock);
300 if (!led_cdev->trigger && led_cdev->default_trigger &&
301 !strcmp(led_cdev->default_trigger, trig->name) &&
302 trigger_relevant(led_cdev, trig)) {
303 led_cdev->flags |= LED_INIT_DEFAULT_TRIGGER;
304 led_trigger_set(led_cdev, trig);
305 }
306 up_write(&led_cdev->trigger_lock);
307 }
308 up_read(&leds_list_lock);
309
310 return 0;
311}
312EXPORT_SYMBOL_GPL(led_trigger_register);
313
314void led_trigger_unregister(struct led_trigger *trig)
315{
316 struct led_classdev *led_cdev;
317
318 if (list_empty_careful(&trig->next_trig))
319 return;
320
321 /* Remove from the list of led triggers */
322 down_write(&triggers_list_lock);
323 list_del_init(&trig->next_trig);
324 up_write(&triggers_list_lock);
325
326 /* Remove anyone actively using this trigger */
327 down_read(&leds_list_lock);
328 list_for_each_entry(led_cdev, &leds_list, node) {
329 down_write(&led_cdev->trigger_lock);
330 if (led_cdev->trigger == trig)
331 led_trigger_set(led_cdev, NULL);
332 up_write(&led_cdev->trigger_lock);
333 }
334 up_read(&leds_list_lock);
335}
336EXPORT_SYMBOL_GPL(led_trigger_unregister);
337
338static void devm_led_trigger_release(struct device *dev, void *res)
339{
340 led_trigger_unregister(*(struct led_trigger **)res);
341}
342
343int devm_led_trigger_register(struct device *dev,
344 struct led_trigger *trig)
345{
346 struct led_trigger **dr;
347 int rc;
348
349 dr = devres_alloc(devm_led_trigger_release, sizeof(*dr),
350 GFP_KERNEL);
351 if (!dr)
352 return -ENOMEM;
353
354 *dr = trig;
355
356 rc = led_trigger_register(trig);
357 if (rc)
358 devres_free(dr);
359 else
360 devres_add(dev, dr);
361
362 return rc;
363}
364EXPORT_SYMBOL_GPL(devm_led_trigger_register);
365
366/* Simple LED Trigger Interface */
367
368void led_trigger_event(struct led_trigger *trig,
369 enum led_brightness brightness)
370{
371 struct led_classdev *led_cdev;
372
373 if (!trig)
374 return;
375
376 rcu_read_lock();
377 list_for_each_entry_rcu(led_cdev, &trig->led_cdevs, trig_list)
378 led_set_brightness(led_cdev, brightness);
379 rcu_read_unlock();
380}
381EXPORT_SYMBOL_GPL(led_trigger_event);
382
383static void led_trigger_blink_setup(struct led_trigger *trig,
384 unsigned long delay_on,
385 unsigned long delay_off,
386 int oneshot,
387 int invert)
388{
389 struct led_classdev *led_cdev;
390
391 if (!trig)
392 return;
393
394 rcu_read_lock();
395 list_for_each_entry_rcu(led_cdev, &trig->led_cdevs, trig_list) {
396 if (oneshot)
397 led_blink_set_oneshot(led_cdev, &delay_on, &delay_off,
398 invert);
399 else
400 led_blink_set_nosleep(led_cdev, delay_on, delay_off);
401 }
402 rcu_read_unlock();
403}
404
405void led_trigger_blink(struct led_trigger *trig,
406 unsigned long delay_on,
407 unsigned long delay_off)
408{
409 led_trigger_blink_setup(trig, delay_on, delay_off, 0, 0);
410}
411EXPORT_SYMBOL_GPL(led_trigger_blink);
412
413void led_trigger_blink_oneshot(struct led_trigger *trig,
414 unsigned long delay_on,
415 unsigned long delay_off,
416 int invert)
417{
418 led_trigger_blink_setup(trig, delay_on, delay_off, 1, invert);
419}
420EXPORT_SYMBOL_GPL(led_trigger_blink_oneshot);
421
422void led_trigger_register_simple(const char *name, struct led_trigger **tp)
423{
424 struct led_trigger *trig;
425 int err;
426
427 trig = kzalloc(sizeof(struct led_trigger), GFP_KERNEL);
428
429 if (trig) {
430 trig->name = name;
431 err = led_trigger_register(trig);
432 if (err < 0) {
433 kfree(trig);
434 trig = NULL;
435 pr_warn("LED trigger %s failed to register (%d)\n",
436 name, err);
437 }
438 } else {
439 pr_warn("LED trigger %s failed to register (no memory)\n",
440 name);
441 }
442 *tp = trig;
443}
444EXPORT_SYMBOL_GPL(led_trigger_register_simple);
445
446void led_trigger_unregister_simple(struct led_trigger *trig)
447{
448 if (trig)
449 led_trigger_unregister(trig);
450 kfree(trig);
451}
452EXPORT_SYMBOL_GPL(led_trigger_unregister_simple);
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);