Loading...
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/module.h>
13#include <linux/kernel.h>
14#include <linux/init.h>
15#include <linux/list.h>
16#include <linux/spinlock.h>
17#include <linux/device.h>
18#include <linux/sysdev.h>
19#include <linux/timer.h>
20#include <linux/err.h>
21#include <linux/ctype.h>
22#include <linux/leds.h>
23#include "leds.h"
24
25static struct class *leds_class;
26
27static void led_update_brightness(struct led_classdev *led_cdev)
28{
29 if (led_cdev->brightness_get)
30 led_cdev->brightness = led_cdev->brightness_get(led_cdev);
31}
32
33static ssize_t led_brightness_show(struct device *dev,
34 struct device_attribute *attr, char *buf)
35{
36 struct led_classdev *led_cdev = dev_get_drvdata(dev);
37
38 /* no lock needed for this */
39 led_update_brightness(led_cdev);
40
41 return sprintf(buf, "%u\n", led_cdev->brightness);
42}
43
44static ssize_t led_brightness_store(struct device *dev,
45 struct device_attribute *attr, const char *buf, size_t size)
46{
47 struct led_classdev *led_cdev = dev_get_drvdata(dev);
48 ssize_t ret = -EINVAL;
49 char *after;
50 unsigned long state = simple_strtoul(buf, &after, 10);
51 size_t count = after - buf;
52
53 if (isspace(*after))
54 count++;
55
56 if (count == size) {
57 ret = count;
58
59 if (state == LED_OFF)
60 led_trigger_remove(led_cdev);
61 led_set_brightness(led_cdev, state);
62 }
63
64 return ret;
65}
66
67static ssize_t led_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}
74
75static struct device_attribute led_class_attrs[] = {
76 __ATTR(brightness, 0644, led_brightness_show, led_brightness_store),
77 __ATTR(max_brightness, 0444, led_max_brightness_show, NULL),
78#ifdef CONFIG_LEDS_TRIGGERS
79 __ATTR(trigger, 0644, led_trigger_show, led_trigger_store),
80#endif
81 __ATTR_NULL,
82};
83
84static void led_timer_function(unsigned long data)
85{
86 struct led_classdev *led_cdev = (void *)data;
87 unsigned long brightness;
88 unsigned long delay;
89
90 if (!led_cdev->blink_delay_on || !led_cdev->blink_delay_off) {
91 led_set_brightness(led_cdev, LED_OFF);
92 return;
93 }
94
95 brightness = led_get_brightness(led_cdev);
96 if (!brightness) {
97 /* Time to switch the LED on. */
98 brightness = led_cdev->blink_brightness;
99 delay = led_cdev->blink_delay_on;
100 } else {
101 /* Store the current brightness value to be able
102 * to restore it when the delay_off period is over.
103 */
104 led_cdev->blink_brightness = brightness;
105 brightness = LED_OFF;
106 delay = led_cdev->blink_delay_off;
107 }
108
109 led_set_brightness(led_cdev, brightness);
110
111 mod_timer(&led_cdev->blink_timer, jiffies + msecs_to_jiffies(delay));
112}
113
114static void led_stop_software_blink(struct led_classdev *led_cdev)
115{
116 /* deactivate previous settings */
117 del_timer_sync(&led_cdev->blink_timer);
118 led_cdev->blink_delay_on = 0;
119 led_cdev->blink_delay_off = 0;
120}
121
122static void led_set_software_blink(struct led_classdev *led_cdev,
123 unsigned long delay_on,
124 unsigned long delay_off)
125{
126 int current_brightness;
127
128 current_brightness = led_get_brightness(led_cdev);
129 if (current_brightness)
130 led_cdev->blink_brightness = current_brightness;
131 if (!led_cdev->blink_brightness)
132 led_cdev->blink_brightness = led_cdev->max_brightness;
133
134 if (led_get_trigger_data(led_cdev) &&
135 delay_on == led_cdev->blink_delay_on &&
136 delay_off == led_cdev->blink_delay_off)
137 return;
138
139 led_stop_software_blink(led_cdev);
140
141 led_cdev->blink_delay_on = delay_on;
142 led_cdev->blink_delay_off = delay_off;
143
144 /* never on - don't blink */
145 if (!delay_on)
146 return;
147
148 /* never off - just set to brightness */
149 if (!delay_off) {
150 led_set_brightness(led_cdev, led_cdev->blink_brightness);
151 return;
152 }
153
154 mod_timer(&led_cdev->blink_timer, jiffies + 1);
155}
156
157
158/**
159 * led_classdev_suspend - suspend an led_classdev.
160 * @led_cdev: the led_classdev to suspend.
161 */
162void led_classdev_suspend(struct led_classdev *led_cdev)
163{
164 led_cdev->flags |= LED_SUSPENDED;
165 led_cdev->brightness_set(led_cdev, 0);
166}
167EXPORT_SYMBOL_GPL(led_classdev_suspend);
168
169/**
170 * led_classdev_resume - resume an led_classdev.
171 * @led_cdev: the led_classdev to resume.
172 */
173void led_classdev_resume(struct led_classdev *led_cdev)
174{
175 led_cdev->brightness_set(led_cdev, led_cdev->brightness);
176 led_cdev->flags &= ~LED_SUSPENDED;
177}
178EXPORT_SYMBOL_GPL(led_classdev_resume);
179
180static int led_suspend(struct device *dev, pm_message_t state)
181{
182 struct led_classdev *led_cdev = dev_get_drvdata(dev);
183
184 if (led_cdev->flags & LED_CORE_SUSPENDRESUME)
185 led_classdev_suspend(led_cdev);
186
187 return 0;
188}
189
190static int led_resume(struct device *dev)
191{
192 struct led_classdev *led_cdev = dev_get_drvdata(dev);
193
194 if (led_cdev->flags & LED_CORE_SUSPENDRESUME)
195 led_classdev_resume(led_cdev);
196
197 return 0;
198}
199
200/**
201 * led_classdev_register - register a new object of led_classdev class.
202 * @parent: The device to register.
203 * @led_cdev: the led_classdev structure for this device.
204 */
205int led_classdev_register(struct device *parent, struct led_classdev *led_cdev)
206{
207 led_cdev->dev = device_create(leds_class, parent, 0, led_cdev,
208 "%s", led_cdev->name);
209 if (IS_ERR(led_cdev->dev))
210 return PTR_ERR(led_cdev->dev);
211
212#ifdef CONFIG_LEDS_TRIGGERS
213 init_rwsem(&led_cdev->trigger_lock);
214#endif
215 /* add to the list of leds */
216 down_write(&leds_list_lock);
217 list_add_tail(&led_cdev->node, &leds_list);
218 up_write(&leds_list_lock);
219
220 if (!led_cdev->max_brightness)
221 led_cdev->max_brightness = LED_FULL;
222
223 led_update_brightness(led_cdev);
224
225 init_timer(&led_cdev->blink_timer);
226 led_cdev->blink_timer.function = led_timer_function;
227 led_cdev->blink_timer.data = (unsigned long)led_cdev;
228
229#ifdef CONFIG_LEDS_TRIGGERS
230 led_trigger_set_default(led_cdev);
231#endif
232
233 printk(KERN_DEBUG "Registered led device: %s\n",
234 led_cdev->name);
235
236 return 0;
237}
238EXPORT_SYMBOL_GPL(led_classdev_register);
239
240/**
241 * led_classdev_unregister - unregisters a object of led_properties class.
242 * @led_cdev: the led device to unregister
243 *
244 * Unregisters a previously registered via led_classdev_register object.
245 */
246void led_classdev_unregister(struct led_classdev *led_cdev)
247{
248#ifdef CONFIG_LEDS_TRIGGERS
249 down_write(&led_cdev->trigger_lock);
250 if (led_cdev->trigger)
251 led_trigger_set(led_cdev, NULL);
252 up_write(&led_cdev->trigger_lock);
253#endif
254
255 /* Stop blinking */
256 led_brightness_set(led_cdev, LED_OFF);
257
258 device_unregister(led_cdev->dev);
259
260 down_write(&leds_list_lock);
261 list_del(&led_cdev->node);
262 up_write(&leds_list_lock);
263}
264EXPORT_SYMBOL_GPL(led_classdev_unregister);
265
266void led_blink_set(struct led_classdev *led_cdev,
267 unsigned long *delay_on,
268 unsigned long *delay_off)
269{
270 if (led_cdev->blink_set &&
271 !led_cdev->blink_set(led_cdev, delay_on, delay_off))
272 return;
273
274 /* blink with 1 Hz as default if nothing specified */
275 if (!*delay_on && !*delay_off)
276 *delay_on = *delay_off = 500;
277
278 led_set_software_blink(led_cdev, *delay_on, *delay_off);
279}
280EXPORT_SYMBOL(led_blink_set);
281
282void led_brightness_set(struct led_classdev *led_cdev,
283 enum led_brightness brightness)
284{
285 led_stop_software_blink(led_cdev);
286 led_cdev->brightness_set(led_cdev, brightness);
287}
288EXPORT_SYMBOL(led_brightness_set);
289
290static int __init leds_init(void)
291{
292 leds_class = class_create(THIS_MODULE, "leds");
293 if (IS_ERR(leds_class))
294 return PTR_ERR(leds_class);
295 leds_class->suspend = led_suspend;
296 leds_class->resume = led_resume;
297 leds_class->dev_attrs = led_class_attrs;
298 return 0;
299}
300
301static void __exit leds_exit(void)
302{
303 class_destroy(leds_class);
304}
305
306subsys_initcall(leds_init);
307module_exit(leds_exit);
308
309MODULE_AUTHOR("John Lenz, Richard Purdie");
310MODULE_LICENSE("GPL");
311MODULE_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 <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");