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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * LED Class Core
4 *
5 * Copyright (C) 2005 John Lenz <lenz@cs.wisc.edu>
6 * Copyright (C) 2005-2007 Richard Purdie <rpurdie@openedhand.com>
7 */
8
9#include <linux/ctype.h>
10#include <linux/device.h>
11#include <linux/err.h>
12#include <linux/init.h>
13#include <linux/kernel.h>
14#include <linux/leds.h>
15#include <linux/list.h>
16#include <linux/module.h>
17#include <linux/property.h>
18#include <linux/slab.h>
19#include <linux/spinlock.h>
20#include <linux/timer.h>
21#include <uapi/linux/uleds.h>
22#include <linux/of.h>
23#include "leds.h"
24
25static struct class *leds_class;
26
27static ssize_t brightness_show(struct device *dev,
28 struct device_attribute *attr, char *buf)
29{
30 struct led_classdev *led_cdev = dev_get_drvdata(dev);
31
32 /* no lock needed for this */
33 led_update_brightness(led_cdev);
34
35 return sprintf(buf, "%u\n", led_cdev->brightness);
36}
37
38static ssize_t brightness_store(struct device *dev,
39 struct device_attribute *attr, const char *buf, size_t size)
40{
41 struct led_classdev *led_cdev = dev_get_drvdata(dev);
42 unsigned long state;
43 ssize_t ret;
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 ret = kstrtoul(buf, 10, &state);
53 if (ret)
54 goto unlock;
55
56 if (state == LED_OFF)
57 led_trigger_remove(led_cdev);
58 led_set_brightness(led_cdev, state);
59 flush_work(&led_cdev->set_brightness_work);
60
61 ret = size;
62unlock:
63 mutex_unlock(&led_cdev->led_access);
64 return ret;
65}
66static DEVICE_ATTR_RW(brightness);
67
68static ssize_t max_brightness_show(struct device *dev,
69 struct device_attribute *attr, char *buf)
70{
71 struct led_classdev *led_cdev = dev_get_drvdata(dev);
72
73 return sprintf(buf, "%u\n", led_cdev->max_brightness);
74}
75static DEVICE_ATTR_RO(max_brightness);
76
77#ifdef CONFIG_LEDS_TRIGGERS
78static BIN_ATTR(trigger, 0644, led_trigger_read, led_trigger_write, 0);
79static struct bin_attribute *led_trigger_bin_attrs[] = {
80 &bin_attr_trigger,
81 NULL,
82};
83static const struct attribute_group led_trigger_group = {
84 .bin_attrs = led_trigger_bin_attrs,
85};
86#endif
87
88static struct attribute *led_class_attrs[] = {
89 &dev_attr_brightness.attr,
90 &dev_attr_max_brightness.attr,
91 NULL,
92};
93
94static const struct attribute_group led_group = {
95 .attrs = led_class_attrs,
96};
97
98static const struct attribute_group *led_groups[] = {
99 &led_group,
100#ifdef CONFIG_LEDS_TRIGGERS
101 &led_trigger_group,
102#endif
103 NULL,
104};
105
106#ifdef CONFIG_LEDS_BRIGHTNESS_HW_CHANGED
107static ssize_t brightness_hw_changed_show(struct device *dev,
108 struct device_attribute *attr, char *buf)
109{
110 struct led_classdev *led_cdev = dev_get_drvdata(dev);
111
112 if (led_cdev->brightness_hw_changed == -1)
113 return -ENODATA;
114
115 return sprintf(buf, "%u\n", led_cdev->brightness_hw_changed);
116}
117
118static DEVICE_ATTR_RO(brightness_hw_changed);
119
120static int led_add_brightness_hw_changed(struct led_classdev *led_cdev)
121{
122 struct device *dev = led_cdev->dev;
123 int ret;
124
125 ret = device_create_file(dev, &dev_attr_brightness_hw_changed);
126 if (ret) {
127 dev_err(dev, "Error creating brightness_hw_changed\n");
128 return ret;
129 }
130
131 led_cdev->brightness_hw_changed_kn =
132 sysfs_get_dirent(dev->kobj.sd, "brightness_hw_changed");
133 if (!led_cdev->brightness_hw_changed_kn) {
134 dev_err(dev, "Error getting brightness_hw_changed kn\n");
135 device_remove_file(dev, &dev_attr_brightness_hw_changed);
136 return -ENXIO;
137 }
138
139 return 0;
140}
141
142static void led_remove_brightness_hw_changed(struct led_classdev *led_cdev)
143{
144 sysfs_put(led_cdev->brightness_hw_changed_kn);
145 device_remove_file(led_cdev->dev, &dev_attr_brightness_hw_changed);
146}
147
148void led_classdev_notify_brightness_hw_changed(struct led_classdev *led_cdev,
149 enum led_brightness brightness)
150{
151 if (WARN_ON(!led_cdev->brightness_hw_changed_kn))
152 return;
153
154 led_cdev->brightness_hw_changed = brightness;
155 sysfs_notify_dirent(led_cdev->brightness_hw_changed_kn);
156}
157EXPORT_SYMBOL_GPL(led_classdev_notify_brightness_hw_changed);
158#else
159static int led_add_brightness_hw_changed(struct led_classdev *led_cdev)
160{
161 return 0;
162}
163static void led_remove_brightness_hw_changed(struct led_classdev *led_cdev)
164{
165}
166#endif
167
168/**
169 * led_classdev_suspend - suspend an led_classdev.
170 * @led_cdev: the led_classdev to suspend.
171 */
172void led_classdev_suspend(struct led_classdev *led_cdev)
173{
174 led_cdev->flags |= LED_SUSPENDED;
175 led_set_brightness_nopm(led_cdev, 0);
176 flush_work(&led_cdev->set_brightness_work);
177}
178EXPORT_SYMBOL_GPL(led_classdev_suspend);
179
180/**
181 * led_classdev_resume - resume an led_classdev.
182 * @led_cdev: the led_classdev to resume.
183 */
184void led_classdev_resume(struct led_classdev *led_cdev)
185{
186 led_set_brightness_nopm(led_cdev, led_cdev->brightness);
187
188 if (led_cdev->flash_resume)
189 led_cdev->flash_resume(led_cdev);
190
191 led_cdev->flags &= ~LED_SUSPENDED;
192}
193EXPORT_SYMBOL_GPL(led_classdev_resume);
194
195#ifdef CONFIG_PM_SLEEP
196static int led_suspend(struct device *dev)
197{
198 struct led_classdev *led_cdev = dev_get_drvdata(dev);
199
200 if (led_cdev->flags & LED_CORE_SUSPENDRESUME)
201 led_classdev_suspend(led_cdev);
202
203 return 0;
204}
205
206static int led_resume(struct device *dev)
207{
208 struct led_classdev *led_cdev = dev_get_drvdata(dev);
209
210 if (led_cdev->flags & LED_CORE_SUSPENDRESUME)
211 led_classdev_resume(led_cdev);
212
213 return 0;
214}
215#endif
216
217static SIMPLE_DEV_PM_OPS(leds_class_dev_pm_ops, led_suspend, led_resume);
218
219/**
220 * of_led_get() - request a LED device via the LED framework
221 * @np: device node to get the LED device from
222 * @index: the index of the LED
223 *
224 * Returns the LED device parsed from the phandle specified in the "leds"
225 * property of a device tree node or a negative error-code on failure.
226 */
227struct led_classdev *of_led_get(struct device_node *np, int index)
228{
229 struct device *led_dev;
230 struct led_classdev *led_cdev;
231 struct device_node *led_node;
232
233 led_node = of_parse_phandle(np, "leds", index);
234 if (!led_node)
235 return ERR_PTR(-ENOENT);
236
237 led_dev = class_find_device_by_of_node(leds_class, led_node);
238 of_node_put(led_node);
239
240 if (!led_dev)
241 return ERR_PTR(-EPROBE_DEFER);
242
243 led_cdev = dev_get_drvdata(led_dev);
244
245 if (!try_module_get(led_cdev->dev->parent->driver->owner))
246 return ERR_PTR(-ENODEV);
247
248 return led_cdev;
249}
250EXPORT_SYMBOL_GPL(of_led_get);
251
252/**
253 * led_put() - release a LED device
254 * @led_cdev: LED device
255 */
256void led_put(struct led_classdev *led_cdev)
257{
258 module_put(led_cdev->dev->parent->driver->owner);
259}
260EXPORT_SYMBOL_GPL(led_put);
261
262static void devm_led_release(struct device *dev, void *res)
263{
264 struct led_classdev **p = res;
265
266 led_put(*p);
267}
268
269/**
270 * devm_of_led_get - Resource-managed request of a LED device
271 * @dev: LED consumer
272 * @index: index of the LED to obtain in the consumer
273 *
274 * The device node of the device is parse to find the request LED device.
275 * The LED device returned from this function is automatically released
276 * on driver detach.
277 *
278 * @return a pointer to a LED device or ERR_PTR(errno) on failure.
279 */
280struct led_classdev *__must_check devm_of_led_get(struct device *dev,
281 int index)
282{
283 struct led_classdev *led;
284 struct led_classdev **dr;
285
286 if (!dev)
287 return ERR_PTR(-EINVAL);
288
289 /* Not using device tree? */
290 if (!IS_ENABLED(CONFIG_OF) || !dev->of_node)
291 return ERR_PTR(-ENOTSUPP);
292
293 led = of_led_get(dev->of_node, index);
294 if (IS_ERR(led))
295 return led;
296
297 dr = devres_alloc(devm_led_release, sizeof(struct led_classdev *),
298 GFP_KERNEL);
299 if (!dr) {
300 led_put(led);
301 return ERR_PTR(-ENOMEM);
302 }
303
304 *dr = led;
305 devres_add(dev, dr);
306
307 return led;
308}
309EXPORT_SYMBOL_GPL(devm_of_led_get);
310
311static int led_classdev_next_name(const char *init_name, char *name,
312 size_t len)
313{
314 unsigned int i = 0;
315 int ret = 0;
316 struct device *dev;
317
318 strlcpy(name, init_name, len);
319
320 while ((ret < len) &&
321 (dev = class_find_device_by_name(leds_class, name))) {
322 put_device(dev);
323 ret = snprintf(name, len, "%s_%u", init_name, ++i);
324 }
325
326 if (ret >= len)
327 return -ENOMEM;
328
329 return i;
330}
331
332/**
333 * led_classdev_register_ext - register a new object of led_classdev class
334 * with init data.
335 *
336 * @parent: parent of LED device
337 * @led_cdev: the led_classdev structure for this device.
338 * @init_data: LED class device initialization data
339 */
340int led_classdev_register_ext(struct device *parent,
341 struct led_classdev *led_cdev,
342 struct led_init_data *init_data)
343{
344 char composed_name[LED_MAX_NAME_SIZE];
345 char final_name[LED_MAX_NAME_SIZE];
346 const char *proposed_name = composed_name;
347 int ret;
348
349 if (init_data) {
350 if (init_data->devname_mandatory && !init_data->devicename) {
351 dev_err(parent, "Mandatory device name is missing");
352 return -EINVAL;
353 }
354 ret = led_compose_name(parent, init_data, composed_name);
355 if (ret < 0)
356 return ret;
357 } else {
358 proposed_name = led_cdev->name;
359 }
360
361 ret = led_classdev_next_name(proposed_name, final_name, sizeof(final_name));
362 if (ret < 0)
363 return ret;
364
365 mutex_init(&led_cdev->led_access);
366 mutex_lock(&led_cdev->led_access);
367 led_cdev->dev = device_create_with_groups(leds_class, parent, 0,
368 led_cdev, led_cdev->groups, "%s", final_name);
369 if (IS_ERR(led_cdev->dev)) {
370 mutex_unlock(&led_cdev->led_access);
371 return PTR_ERR(led_cdev->dev);
372 }
373 if (init_data && init_data->fwnode) {
374 led_cdev->dev->fwnode = init_data->fwnode;
375 led_cdev->dev->of_node = to_of_node(init_data->fwnode);
376 }
377
378 if (ret)
379 dev_warn(parent, "Led %s renamed to %s due to name collision",
380 proposed_name, dev_name(led_cdev->dev));
381
382 if (led_cdev->flags & LED_BRIGHT_HW_CHANGED) {
383 ret = led_add_brightness_hw_changed(led_cdev);
384 if (ret) {
385 device_unregister(led_cdev->dev);
386 led_cdev->dev = NULL;
387 mutex_unlock(&led_cdev->led_access);
388 return ret;
389 }
390 }
391
392 led_cdev->work_flags = 0;
393#ifdef CONFIG_LEDS_TRIGGERS
394 init_rwsem(&led_cdev->trigger_lock);
395#endif
396#ifdef CONFIG_LEDS_BRIGHTNESS_HW_CHANGED
397 led_cdev->brightness_hw_changed = -1;
398#endif
399 /* add to the list of leds */
400 down_write(&leds_list_lock);
401 list_add_tail(&led_cdev->node, &leds_list);
402 up_write(&leds_list_lock);
403
404 if (!led_cdev->max_brightness)
405 led_cdev->max_brightness = LED_FULL;
406
407 led_update_brightness(led_cdev);
408
409 led_init_core(led_cdev);
410
411#ifdef CONFIG_LEDS_TRIGGERS
412 led_trigger_set_default(led_cdev);
413#endif
414
415 mutex_unlock(&led_cdev->led_access);
416
417 dev_dbg(parent, "Registered led device: %s\n",
418 led_cdev->name);
419
420 return 0;
421}
422EXPORT_SYMBOL_GPL(led_classdev_register_ext);
423
424/**
425 * led_classdev_unregister - unregisters a object of led_properties class.
426 * @led_cdev: the led device to unregister
427 *
428 * Unregisters a previously registered via led_classdev_register object.
429 */
430void led_classdev_unregister(struct led_classdev *led_cdev)
431{
432 if (IS_ERR_OR_NULL(led_cdev->dev))
433 return;
434
435#ifdef CONFIG_LEDS_TRIGGERS
436 down_write(&led_cdev->trigger_lock);
437 if (led_cdev->trigger)
438 led_trigger_set(led_cdev, NULL);
439 up_write(&led_cdev->trigger_lock);
440#endif
441
442 led_cdev->flags |= LED_UNREGISTERING;
443
444 /* Stop blinking */
445 led_stop_software_blink(led_cdev);
446
447 led_set_brightness(led_cdev, LED_OFF);
448
449 flush_work(&led_cdev->set_brightness_work);
450
451 if (led_cdev->flags & LED_BRIGHT_HW_CHANGED)
452 led_remove_brightness_hw_changed(led_cdev);
453
454 device_unregister(led_cdev->dev);
455
456 down_write(&leds_list_lock);
457 list_del(&led_cdev->node);
458 up_write(&leds_list_lock);
459
460 mutex_destroy(&led_cdev->led_access);
461}
462EXPORT_SYMBOL_GPL(led_classdev_unregister);
463
464static void devm_led_classdev_release(struct device *dev, void *res)
465{
466 led_classdev_unregister(*(struct led_classdev **)res);
467}
468
469/**
470 * devm_led_classdev_register_ext - resource managed led_classdev_register_ext()
471 *
472 * @parent: parent of LED device
473 * @led_cdev: the led_classdev structure for this device.
474 * @init_data: LED class device initialization data
475 */
476int devm_led_classdev_register_ext(struct device *parent,
477 struct led_classdev *led_cdev,
478 struct led_init_data *init_data)
479{
480 struct led_classdev **dr;
481 int rc;
482
483 dr = devres_alloc(devm_led_classdev_release, sizeof(*dr), GFP_KERNEL);
484 if (!dr)
485 return -ENOMEM;
486
487 rc = led_classdev_register_ext(parent, led_cdev, init_data);
488 if (rc) {
489 devres_free(dr);
490 return rc;
491 }
492
493 *dr = led_cdev;
494 devres_add(parent, dr);
495
496 return 0;
497}
498EXPORT_SYMBOL_GPL(devm_led_classdev_register_ext);
499
500static int devm_led_classdev_match(struct device *dev, void *res, void *data)
501{
502 struct led_classdev **p = res;
503
504 if (WARN_ON(!p || !*p))
505 return 0;
506
507 return *p == data;
508}
509
510/**
511 * devm_led_classdev_unregister() - resource managed led_classdev_unregister()
512 * @parent: The device to unregister.
513 * @led_cdev: the led_classdev structure for this device.
514 */
515void devm_led_classdev_unregister(struct device *dev,
516 struct led_classdev *led_cdev)
517{
518 WARN_ON(devres_release(dev,
519 devm_led_classdev_release,
520 devm_led_classdev_match, led_cdev));
521}
522EXPORT_SYMBOL_GPL(devm_led_classdev_unregister);
523
524static int __init leds_init(void)
525{
526 leds_class = class_create(THIS_MODULE, "leds");
527 if (IS_ERR(leds_class))
528 return PTR_ERR(leds_class);
529 leds_class->pm = &leds_class_dev_pm_ops;
530 leds_class->dev_groups = led_groups;
531 return 0;
532}
533
534static void __exit leds_exit(void)
535{
536 class_destroy(leds_class);
537}
538
539subsys_initcall(leds_init);
540module_exit(leds_exit);
541
542MODULE_AUTHOR("John Lenz, Richard Purdie");
543MODULE_LICENSE("GPL");
544MODULE_DESCRIPTION("LED Class Interface");
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * LED Class Core
4 *
5 * Copyright (C) 2005 John Lenz <lenz@cs.wisc.edu>
6 * Copyright (C) 2005-2007 Richard Purdie <rpurdie@openedhand.com>
7 */
8
9#include <linux/ctype.h>
10#include <linux/device.h>
11#include <linux/err.h>
12#include <linux/init.h>
13#include <linux/kernel.h>
14#include <linux/leds.h>
15#include <linux/list.h>
16#include <linux/module.h>
17#include <linux/property.h>
18#include <linux/slab.h>
19#include <linux/spinlock.h>
20#include <linux/timer.h>
21#include <uapi/linux/uleds.h>
22#include "leds.h"
23
24static struct class *leds_class;
25
26static ssize_t brightness_show(struct device *dev,
27 struct device_attribute *attr, char *buf)
28{
29 struct led_classdev *led_cdev = dev_get_drvdata(dev);
30
31 /* no lock needed for this */
32 led_update_brightness(led_cdev);
33
34 return sprintf(buf, "%u\n", led_cdev->brightness);
35}
36
37static ssize_t brightness_store(struct device *dev,
38 struct device_attribute *attr, const char *buf, size_t size)
39{
40 struct led_classdev *led_cdev = dev_get_drvdata(dev);
41 unsigned long state;
42 ssize_t ret;
43
44 mutex_lock(&led_cdev->led_access);
45
46 if (led_sysfs_is_disabled(led_cdev)) {
47 ret = -EBUSY;
48 goto unlock;
49 }
50
51 ret = kstrtoul(buf, 10, &state);
52 if (ret)
53 goto unlock;
54
55 if (state == LED_OFF)
56 led_trigger_remove(led_cdev);
57 led_set_brightness(led_cdev, state);
58 flush_work(&led_cdev->set_brightness_work);
59
60 ret = size;
61unlock:
62 mutex_unlock(&led_cdev->led_access);
63 return ret;
64}
65static DEVICE_ATTR_RW(brightness);
66
67static ssize_t max_brightness_show(struct device *dev,
68 struct device_attribute *attr, char *buf)
69{
70 struct led_classdev *led_cdev = dev_get_drvdata(dev);
71
72 return sprintf(buf, "%u\n", led_cdev->max_brightness);
73}
74static DEVICE_ATTR_RO(max_brightness);
75
76#ifdef CONFIG_LEDS_TRIGGERS
77static DEVICE_ATTR(trigger, 0644, led_trigger_show, led_trigger_store);
78static struct attribute *led_trigger_attrs[] = {
79 &dev_attr_trigger.attr,
80 NULL,
81};
82static const struct attribute_group led_trigger_group = {
83 .attrs = led_trigger_attrs,
84};
85#endif
86
87static struct attribute *led_class_attrs[] = {
88 &dev_attr_brightness.attr,
89 &dev_attr_max_brightness.attr,
90 NULL,
91};
92
93static const struct attribute_group led_group = {
94 .attrs = led_class_attrs,
95};
96
97static const struct attribute_group *led_groups[] = {
98 &led_group,
99#ifdef CONFIG_LEDS_TRIGGERS
100 &led_trigger_group,
101#endif
102 NULL,
103};
104
105#ifdef CONFIG_LEDS_BRIGHTNESS_HW_CHANGED
106static ssize_t brightness_hw_changed_show(struct device *dev,
107 struct device_attribute *attr, char *buf)
108{
109 struct led_classdev *led_cdev = dev_get_drvdata(dev);
110
111 if (led_cdev->brightness_hw_changed == -1)
112 return -ENODATA;
113
114 return sprintf(buf, "%u\n", led_cdev->brightness_hw_changed);
115}
116
117static DEVICE_ATTR_RO(brightness_hw_changed);
118
119static int led_add_brightness_hw_changed(struct led_classdev *led_cdev)
120{
121 struct device *dev = led_cdev->dev;
122 int ret;
123
124 ret = device_create_file(dev, &dev_attr_brightness_hw_changed);
125 if (ret) {
126 dev_err(dev, "Error creating brightness_hw_changed\n");
127 return ret;
128 }
129
130 led_cdev->brightness_hw_changed_kn =
131 sysfs_get_dirent(dev->kobj.sd, "brightness_hw_changed");
132 if (!led_cdev->brightness_hw_changed_kn) {
133 dev_err(dev, "Error getting brightness_hw_changed kn\n");
134 device_remove_file(dev, &dev_attr_brightness_hw_changed);
135 return -ENXIO;
136 }
137
138 return 0;
139}
140
141static void led_remove_brightness_hw_changed(struct led_classdev *led_cdev)
142{
143 sysfs_put(led_cdev->brightness_hw_changed_kn);
144 device_remove_file(led_cdev->dev, &dev_attr_brightness_hw_changed);
145}
146
147void led_classdev_notify_brightness_hw_changed(struct led_classdev *led_cdev,
148 enum led_brightness brightness)
149{
150 if (WARN_ON(!led_cdev->brightness_hw_changed_kn))
151 return;
152
153 led_cdev->brightness_hw_changed = brightness;
154 sysfs_notify_dirent(led_cdev->brightness_hw_changed_kn);
155}
156EXPORT_SYMBOL_GPL(led_classdev_notify_brightness_hw_changed);
157#else
158static int led_add_brightness_hw_changed(struct led_classdev *led_cdev)
159{
160 return 0;
161}
162static void led_remove_brightness_hw_changed(struct led_classdev *led_cdev)
163{
164}
165#endif
166
167/**
168 * led_classdev_suspend - suspend an led_classdev.
169 * @led_cdev: the led_classdev to suspend.
170 */
171void led_classdev_suspend(struct led_classdev *led_cdev)
172{
173 led_cdev->flags |= LED_SUSPENDED;
174 led_set_brightness_nopm(led_cdev, 0);
175}
176EXPORT_SYMBOL_GPL(led_classdev_suspend);
177
178/**
179 * led_classdev_resume - resume an led_classdev.
180 * @led_cdev: the led_classdev to resume.
181 */
182void led_classdev_resume(struct led_classdev *led_cdev)
183{
184 led_set_brightness_nopm(led_cdev, led_cdev->brightness);
185
186 if (led_cdev->flash_resume)
187 led_cdev->flash_resume(led_cdev);
188
189 led_cdev->flags &= ~LED_SUSPENDED;
190}
191EXPORT_SYMBOL_GPL(led_classdev_resume);
192
193#ifdef CONFIG_PM_SLEEP
194static int led_suspend(struct device *dev)
195{
196 struct led_classdev *led_cdev = dev_get_drvdata(dev);
197
198 if (led_cdev->flags & LED_CORE_SUSPENDRESUME)
199 led_classdev_suspend(led_cdev);
200
201 return 0;
202}
203
204static int led_resume(struct device *dev)
205{
206 struct led_classdev *led_cdev = dev_get_drvdata(dev);
207
208 if (led_cdev->flags & LED_CORE_SUSPENDRESUME)
209 led_classdev_resume(led_cdev);
210
211 return 0;
212}
213#endif
214
215static SIMPLE_DEV_PM_OPS(leds_class_dev_pm_ops, led_suspend, led_resume);
216
217static int led_classdev_next_name(const char *init_name, char *name,
218 size_t len)
219{
220 unsigned int i = 0;
221 int ret = 0;
222 struct device *dev;
223
224 strlcpy(name, init_name, len);
225
226 while ((ret < len) &&
227 (dev = class_find_device_by_name(leds_class, name))) {
228 put_device(dev);
229 ret = snprintf(name, len, "%s_%u", init_name, ++i);
230 }
231
232 if (ret >= len)
233 return -ENOMEM;
234
235 return i;
236}
237
238/**
239 * led_classdev_register_ext - register a new object of led_classdev class
240 * with init data.
241 *
242 * @parent: parent of LED device
243 * @led_cdev: the led_classdev structure for this device.
244 * @init_data: LED class device initialization data
245 */
246int led_classdev_register_ext(struct device *parent,
247 struct led_classdev *led_cdev,
248 struct led_init_data *init_data)
249{
250 char composed_name[LED_MAX_NAME_SIZE];
251 char final_name[LED_MAX_NAME_SIZE];
252 const char *proposed_name = composed_name;
253 int ret;
254
255 if (init_data) {
256 if (init_data->devname_mandatory && !init_data->devicename) {
257 dev_err(parent, "Mandatory device name is missing");
258 return -EINVAL;
259 }
260 ret = led_compose_name(parent, init_data, composed_name);
261 if (ret < 0)
262 return ret;
263 } else {
264 proposed_name = led_cdev->name;
265 }
266
267 ret = led_classdev_next_name(proposed_name, final_name, sizeof(final_name));
268 if (ret < 0)
269 return ret;
270
271 mutex_init(&led_cdev->led_access);
272 mutex_lock(&led_cdev->led_access);
273 led_cdev->dev = device_create_with_groups(leds_class, parent, 0,
274 led_cdev, led_cdev->groups, "%s", final_name);
275 if (IS_ERR(led_cdev->dev)) {
276 mutex_unlock(&led_cdev->led_access);
277 return PTR_ERR(led_cdev->dev);
278 }
279 if (init_data && init_data->fwnode)
280 led_cdev->dev->fwnode = init_data->fwnode;
281
282 if (ret)
283 dev_warn(parent, "Led %s renamed to %s due to name collision",
284 led_cdev->name, dev_name(led_cdev->dev));
285
286 if (led_cdev->flags & LED_BRIGHT_HW_CHANGED) {
287 ret = led_add_brightness_hw_changed(led_cdev);
288 if (ret) {
289 device_unregister(led_cdev->dev);
290 led_cdev->dev = NULL;
291 mutex_unlock(&led_cdev->led_access);
292 return ret;
293 }
294 }
295
296 led_cdev->work_flags = 0;
297#ifdef CONFIG_LEDS_TRIGGERS
298 init_rwsem(&led_cdev->trigger_lock);
299#endif
300#ifdef CONFIG_LEDS_BRIGHTNESS_HW_CHANGED
301 led_cdev->brightness_hw_changed = -1;
302#endif
303 /* add to the list of leds */
304 down_write(&leds_list_lock);
305 list_add_tail(&led_cdev->node, &leds_list);
306 up_write(&leds_list_lock);
307
308 if (!led_cdev->max_brightness)
309 led_cdev->max_brightness = LED_FULL;
310
311 led_update_brightness(led_cdev);
312
313 led_init_core(led_cdev);
314
315#ifdef CONFIG_LEDS_TRIGGERS
316 led_trigger_set_default(led_cdev);
317#endif
318
319 mutex_unlock(&led_cdev->led_access);
320
321 dev_dbg(parent, "Registered led device: %s\n",
322 led_cdev->name);
323
324 return 0;
325}
326EXPORT_SYMBOL_GPL(led_classdev_register_ext);
327
328/**
329 * led_classdev_unregister - unregisters a object of led_properties class.
330 * @led_cdev: the led device to unregister
331 *
332 * Unregisters a previously registered via led_classdev_register object.
333 */
334void led_classdev_unregister(struct led_classdev *led_cdev)
335{
336 if (IS_ERR_OR_NULL(led_cdev->dev))
337 return;
338
339#ifdef CONFIG_LEDS_TRIGGERS
340 down_write(&led_cdev->trigger_lock);
341 if (led_cdev->trigger)
342 led_trigger_set(led_cdev, NULL);
343 up_write(&led_cdev->trigger_lock);
344#endif
345
346 led_cdev->flags |= LED_UNREGISTERING;
347
348 /* Stop blinking */
349 led_stop_software_blink(led_cdev);
350
351 led_set_brightness(led_cdev, LED_OFF);
352
353 flush_work(&led_cdev->set_brightness_work);
354
355 if (led_cdev->flags & LED_BRIGHT_HW_CHANGED)
356 led_remove_brightness_hw_changed(led_cdev);
357
358 device_unregister(led_cdev->dev);
359
360 down_write(&leds_list_lock);
361 list_del(&led_cdev->node);
362 up_write(&leds_list_lock);
363
364 mutex_destroy(&led_cdev->led_access);
365}
366EXPORT_SYMBOL_GPL(led_classdev_unregister);
367
368static void devm_led_classdev_release(struct device *dev, void *res)
369{
370 led_classdev_unregister(*(struct led_classdev **)res);
371}
372
373/**
374 * devm_led_classdev_register_ext - resource managed led_classdev_register_ext()
375 *
376 * @parent: parent of LED device
377 * @led_cdev: the led_classdev structure for this device.
378 * @init_data: LED class device initialization data
379 */
380int devm_led_classdev_register_ext(struct device *parent,
381 struct led_classdev *led_cdev,
382 struct led_init_data *init_data)
383{
384 struct led_classdev **dr;
385 int rc;
386
387 dr = devres_alloc(devm_led_classdev_release, sizeof(*dr), GFP_KERNEL);
388 if (!dr)
389 return -ENOMEM;
390
391 rc = led_classdev_register_ext(parent, led_cdev, init_data);
392 if (rc) {
393 devres_free(dr);
394 return rc;
395 }
396
397 *dr = led_cdev;
398 devres_add(parent, dr);
399
400 return 0;
401}
402EXPORT_SYMBOL_GPL(devm_led_classdev_register_ext);
403
404static int devm_led_classdev_match(struct device *dev, void *res, void *data)
405{
406 struct led_cdev **p = res;
407
408 if (WARN_ON(!p || !*p))
409 return 0;
410
411 return *p == data;
412}
413
414/**
415 * devm_led_classdev_unregister() - resource managed led_classdev_unregister()
416 * @parent: The device to unregister.
417 * @led_cdev: the led_classdev structure for this device.
418 */
419void devm_led_classdev_unregister(struct device *dev,
420 struct led_classdev *led_cdev)
421{
422 WARN_ON(devres_release(dev,
423 devm_led_classdev_release,
424 devm_led_classdev_match, led_cdev));
425}
426EXPORT_SYMBOL_GPL(devm_led_classdev_unregister);
427
428static int __init leds_init(void)
429{
430 leds_class = class_create(THIS_MODULE, "leds");
431 if (IS_ERR(leds_class))
432 return PTR_ERR(leds_class);
433 leds_class->pm = &leds_class_dev_pm_ops;
434 leds_class->dev_groups = led_groups;
435 return 0;
436}
437
438static void __exit leds_exit(void)
439{
440 class_destroy(leds_class);
441}
442
443subsys_initcall(leds_init);
444module_exit(leds_exit);
445
446MODULE_AUTHOR("John Lenz, Richard Purdie");
447MODULE_LICENSE("GPL");
448MODULE_DESCRIPTION("LED Class Interface");