Linux Audio

Check our new training course

Loading...
v5.9
  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");
v4.6
 
  1/*
  2 * LED Class Core
  3 *
  4 * Copyright (C) 2005 John Lenz <lenz@cs.wisc.edu>
  5 * Copyright (C) 2005-2007 Richard Purdie <rpurdie@openedhand.com>
  6 *
  7 * This program is free software; you can redistribute it and/or modify
  8 * it under the terms of the GNU General Public License version 2 as
  9 * published by the Free Software Foundation.
 10 */
 11
 12#include <linux/ctype.h>
 13#include <linux/device.h>
 14#include <linux/err.h>
 15#include <linux/init.h>
 16#include <linux/kernel.h>
 17#include <linux/leds.h>
 18#include <linux/list.h>
 19#include <linux/module.h>
 
 20#include <linux/slab.h>
 21#include <linux/spinlock.h>
 22#include <linux/timer.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
 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/**
106 * led_classdev_suspend - suspend an led_classdev.
107 * @led_cdev: the led_classdev to suspend.
108 */
109void led_classdev_suspend(struct led_classdev *led_cdev)
110{
111	led_cdev->flags |= LED_SUSPENDED;
112	led_set_brightness_nopm(led_cdev, 0);
 
113}
114EXPORT_SYMBOL_GPL(led_classdev_suspend);
115
116/**
117 * led_classdev_resume - resume an led_classdev.
118 * @led_cdev: the led_classdev to resume.
119 */
120void led_classdev_resume(struct led_classdev *led_cdev)
121{
122	led_set_brightness_nopm(led_cdev, led_cdev->brightness);
123
124	if (led_cdev->flash_resume)
125		led_cdev->flash_resume(led_cdev);
126
127	led_cdev->flags &= ~LED_SUSPENDED;
128}
129EXPORT_SYMBOL_GPL(led_classdev_resume);
130
131#ifdef CONFIG_PM_SLEEP
132static int led_suspend(struct device *dev)
133{
134	struct led_classdev *led_cdev = dev_get_drvdata(dev);
135
136	if (led_cdev->flags & LED_CORE_SUSPENDRESUME)
137		led_classdev_suspend(led_cdev);
138
139	return 0;
140}
141
142static int led_resume(struct device *dev)
143{
144	struct led_classdev *led_cdev = dev_get_drvdata(dev);
145
146	if (led_cdev->flags & LED_CORE_SUSPENDRESUME)
147		led_classdev_resume(led_cdev);
148
149	return 0;
150}
151#endif
152
153static SIMPLE_DEV_PM_OPS(leds_class_dev_pm_ops, led_suspend, led_resume);
154
155static int match_name(struct device *dev, const void *data)
 
 
 
 
 
 
 
 
156{
157	if (!dev_name(dev))
158		return 0;
159	return !strcmp(dev_name(dev), (char *)data);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
160}
161
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
162static int led_classdev_next_name(const char *init_name, char *name,
163				  size_t len)
164{
165	unsigned int i = 0;
166	int ret = 0;
167	struct device *dev;
168
169	strlcpy(name, init_name, len);
170
171	while ((ret < len) &&
172	       (dev = class_find_device(leds_class, NULL, name, match_name))) {
173		put_device(dev);
174		ret = snprintf(name, len, "%s_%u", init_name, ++i);
175	}
176
177	if (ret >= len)
178		return -ENOMEM;
179
180	return i;
181}
182
183/**
184 * led_classdev_register - register a new object of led_classdev class.
185 * @parent: The device to register.
 
 
186 * @led_cdev: the led_classdev structure for this device.
 
187 */
188int led_classdev_register(struct device *parent, struct led_classdev *led_cdev)
189{
190	char name[64];
 
 
 
 
191	int ret;
192
193	ret = led_classdev_next_name(led_cdev->name, name, sizeof(name));
 
 
 
 
 
 
 
 
 
 
 
 
194	if (ret < 0)
195		return ret;
196
 
 
197	led_cdev->dev = device_create_with_groups(leds_class, parent, 0,
198				led_cdev, led_cdev->groups, "%s", name);
199	if (IS_ERR(led_cdev->dev))
 
200		return PTR_ERR(led_cdev->dev);
 
 
 
 
 
201
202	if (ret)
203		dev_warn(parent, "Led %s renamed to %s due to name collision",
204				led_cdev->name, dev_name(led_cdev->dev));
 
 
 
 
 
 
 
 
 
 
205
 
206#ifdef CONFIG_LEDS_TRIGGERS
207	init_rwsem(&led_cdev->trigger_lock);
208#endif
209	mutex_init(&led_cdev->led_access);
 
 
210	/* add to the list of leds */
211	down_write(&leds_list_lock);
212	list_add_tail(&led_cdev->node, &leds_list);
213	up_write(&leds_list_lock);
214
215	if (!led_cdev->max_brightness)
216		led_cdev->max_brightness = LED_FULL;
217
218	led_update_brightness(led_cdev);
219
220	led_init_core(led_cdev);
221
222#ifdef CONFIG_LEDS_TRIGGERS
223	led_trigger_set_default(led_cdev);
224#endif
225
 
 
226	dev_dbg(parent, "Registered led device: %s\n",
227			led_cdev->name);
228
229	return 0;
230}
231EXPORT_SYMBOL_GPL(led_classdev_register);
232
233/**
234 * led_classdev_unregister - unregisters a object of led_properties class.
235 * @led_cdev: the led device to unregister
236 *
237 * Unregisters a previously registered via led_classdev_register object.
238 */
239void led_classdev_unregister(struct led_classdev *led_cdev)
240{
 
 
 
241#ifdef CONFIG_LEDS_TRIGGERS
242	down_write(&led_cdev->trigger_lock);
243	if (led_cdev->trigger)
244		led_trigger_set(led_cdev, NULL);
245	up_write(&led_cdev->trigger_lock);
246#endif
247
248	led_cdev->flags |= LED_UNREGISTERING;
249
250	/* Stop blinking */
251	led_stop_software_blink(led_cdev);
252
253	led_set_brightness(led_cdev, LED_OFF);
254
255	flush_work(&led_cdev->set_brightness_work);
256
 
 
 
257	device_unregister(led_cdev->dev);
258
259	down_write(&leds_list_lock);
260	list_del(&led_cdev->node);
261	up_write(&leds_list_lock);
262
263	mutex_destroy(&led_cdev->led_access);
264}
265EXPORT_SYMBOL_GPL(led_classdev_unregister);
266
267static void devm_led_classdev_release(struct device *dev, void *res)
268{
269	led_classdev_unregister(*(struct led_classdev **)res);
270}
271
272/**
273 * devm_led_classdev_register - resource managed led_classdev_register()
274 * @parent: The device to register.
 
275 * @led_cdev: the led_classdev structure for this device.
 
276 */
277int devm_led_classdev_register(struct device *parent,
278			       struct led_classdev *led_cdev)
 
279{
280	struct led_classdev **dr;
281	int rc;
282
283	dr = devres_alloc(devm_led_classdev_release, sizeof(*dr), GFP_KERNEL);
284	if (!dr)
285		return -ENOMEM;
286
287	rc = led_classdev_register(parent, led_cdev);
288	if (rc) {
289		devres_free(dr);
290		return rc;
291	}
292
293	*dr = led_cdev;
294	devres_add(parent, dr);
295
296	return 0;
297}
298EXPORT_SYMBOL_GPL(devm_led_classdev_register);
299
300static int devm_led_classdev_match(struct device *dev, void *res, void *data)
301{
302	struct led_cdev **p = res;
303
304	if (WARN_ON(!p || !*p))
305		return 0;
306
307	return *p == data;
308}
309
310/**
311 * devm_led_classdev_unregister() - resource managed led_classdev_unregister()
312 * @parent: The device to unregister.
313 * @led_cdev: the led_classdev structure for this device.
314 */
315void devm_led_classdev_unregister(struct device *dev,
316				  struct led_classdev *led_cdev)
317{
318	WARN_ON(devres_release(dev,
319			       devm_led_classdev_release,
320			       devm_led_classdev_match, led_cdev));
321}
322EXPORT_SYMBOL_GPL(devm_led_classdev_unregister);
323
324static int __init leds_init(void)
325{
326	leds_class = class_create(THIS_MODULE, "leds");
327	if (IS_ERR(leds_class))
328		return PTR_ERR(leds_class);
329	leds_class->pm = &leds_class_dev_pm_ops;
330	leds_class->dev_groups = led_groups;
331	return 0;
332}
333
334static void __exit leds_exit(void)
335{
336	class_destroy(leds_class);
337}
338
339subsys_initcall(leds_init);
340module_exit(leds_exit);
341
342MODULE_AUTHOR("John Lenz, Richard Purdie");
343MODULE_LICENSE("GPL");
344MODULE_DESCRIPTION("LED Class Interface");