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.
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 <uapi/linux/uleds.h>
26 static struct class *leds_class;
28 static ssize_t brightness_show(struct device *dev,
29 struct device_attribute *attr, char *buf)
31 struct led_classdev *led_cdev = dev_get_drvdata(dev);
33 /* no lock needed for this */
34 led_update_brightness(led_cdev);
36 return sprintf(buf, "%u\n", led_cdev->brightness);
39 static ssize_t brightness_store(struct device *dev,
40 struct device_attribute *attr, const char *buf, size_t size)
42 struct led_classdev *led_cdev = dev_get_drvdata(dev);
46 mutex_lock(&led_cdev->led_access);
48 if (led_sysfs_is_disabled(led_cdev)) {
53 ret = kstrtoul(buf, 10, &state);
58 led_trigger_remove(led_cdev);
59 led_set_brightness(led_cdev, state);
63 mutex_unlock(&led_cdev->led_access);
66 static DEVICE_ATTR_RW(brightness);
68 static ssize_t max_brightness_show(struct device *dev,
69 struct device_attribute *attr, char *buf)
71 struct led_classdev *led_cdev = dev_get_drvdata(dev);
73 return sprintf(buf, "%u\n", led_cdev->max_brightness);
75 static DEVICE_ATTR_RO(max_brightness);
77 #ifdef CONFIG_LEDS_TRIGGERS
78 static DEVICE_ATTR(trigger, 0644, led_trigger_show, led_trigger_store);
79 static struct attribute *led_trigger_attrs[] = {
80 &dev_attr_trigger.attr,
83 static const struct attribute_group led_trigger_group = {
84 .attrs = led_trigger_attrs,
88 static struct attribute *led_class_attrs[] = {
89 &dev_attr_brightness.attr,
90 &dev_attr_max_brightness.attr,
94 static const struct attribute_group led_group = {
95 .attrs = led_class_attrs,
98 static const struct attribute_group *led_groups[] = {
100 #ifdef CONFIG_LEDS_TRIGGERS
107 * led_classdev_suspend - suspend an led_classdev.
108 * @led_cdev: the led_classdev to suspend.
110 void led_classdev_suspend(struct led_classdev *led_cdev)
112 led_cdev->flags |= LED_SUSPENDED;
113 led_set_brightness_nopm(led_cdev, 0);
115 EXPORT_SYMBOL_GPL(led_classdev_suspend);
118 * led_classdev_resume - resume an led_classdev.
119 * @led_cdev: the led_classdev to resume.
121 void led_classdev_resume(struct led_classdev *led_cdev)
123 led_set_brightness_nopm(led_cdev, led_cdev->brightness);
125 if (led_cdev->flash_resume)
126 led_cdev->flash_resume(led_cdev);
128 led_cdev->flags &= ~LED_SUSPENDED;
130 EXPORT_SYMBOL_GPL(led_classdev_resume);
132 #ifdef CONFIG_PM_SLEEP
133 static int led_suspend(struct device *dev)
135 struct led_classdev *led_cdev = dev_get_drvdata(dev);
137 if (led_cdev->flags & LED_CORE_SUSPENDRESUME)
138 led_classdev_suspend(led_cdev);
143 static int led_resume(struct device *dev)
145 struct led_classdev *led_cdev = dev_get_drvdata(dev);
147 if (led_cdev->flags & LED_CORE_SUSPENDRESUME)
148 led_classdev_resume(led_cdev);
154 static SIMPLE_DEV_PM_OPS(leds_class_dev_pm_ops, led_suspend, led_resume);
156 static int match_name(struct device *dev, const void *data)
160 return !strcmp(dev_name(dev), (char *)data);
163 static int led_classdev_next_name(const char *init_name, char *name,
170 strlcpy(name, init_name, len);
172 while ((ret < len) &&
173 (dev = class_find_device(leds_class, NULL, name, match_name))) {
175 ret = snprintf(name, len, "%s_%u", init_name, ++i);
185 * led_classdev_register - register a new object of led_classdev class.
186 * @parent: The device to register.
187 * @led_cdev: the led_classdev structure for this device.
189 int led_classdev_register(struct device *parent, struct led_classdev *led_cdev)
191 char name[LED_MAX_NAME_SIZE];
194 ret = led_classdev_next_name(led_cdev->name, name, sizeof(name));
198 led_cdev->dev = device_create_with_groups(leds_class, parent, 0,
199 led_cdev, led_cdev->groups, "%s", name);
200 if (IS_ERR(led_cdev->dev))
201 return PTR_ERR(led_cdev->dev);
204 dev_warn(parent, "Led %s renamed to %s due to name collision",
205 led_cdev->name, dev_name(led_cdev->dev));
207 led_cdev->work_flags = 0;
208 #ifdef CONFIG_LEDS_TRIGGERS
209 init_rwsem(&led_cdev->trigger_lock);
211 mutex_init(&led_cdev->led_access);
212 /* add to the list of leds */
213 down_write(&leds_list_lock);
214 list_add_tail(&led_cdev->node, &leds_list);
215 up_write(&leds_list_lock);
217 if (!led_cdev->max_brightness)
218 led_cdev->max_brightness = LED_FULL;
220 led_update_brightness(led_cdev);
222 led_init_core(led_cdev);
224 #ifdef CONFIG_LEDS_TRIGGERS
225 led_trigger_set_default(led_cdev);
228 dev_dbg(parent, "Registered led device: %s\n",
233 EXPORT_SYMBOL_GPL(led_classdev_register);
236 * led_classdev_unregister - unregisters a object of led_properties class.
237 * @led_cdev: the led device to unregister
239 * Unregisters a previously registered via led_classdev_register object.
241 void led_classdev_unregister(struct led_classdev *led_cdev)
243 #ifdef CONFIG_LEDS_TRIGGERS
244 down_write(&led_cdev->trigger_lock);
245 if (led_cdev->trigger)
246 led_trigger_set(led_cdev, NULL);
247 up_write(&led_cdev->trigger_lock);
250 led_cdev->flags |= LED_UNREGISTERING;
253 led_stop_software_blink(led_cdev);
255 led_set_brightness(led_cdev, LED_OFF);
257 flush_work(&led_cdev->set_brightness_work);
259 device_unregister(led_cdev->dev);
261 down_write(&leds_list_lock);
262 list_del(&led_cdev->node);
263 up_write(&leds_list_lock);
265 mutex_destroy(&led_cdev->led_access);
267 EXPORT_SYMBOL_GPL(led_classdev_unregister);
269 static void devm_led_classdev_release(struct device *dev, void *res)
271 led_classdev_unregister(*(struct led_classdev **)res);
275 * devm_led_classdev_register - resource managed led_classdev_register()
276 * @parent: The device to register.
277 * @led_cdev: the led_classdev structure for this device.
279 int devm_led_classdev_register(struct device *parent,
280 struct led_classdev *led_cdev)
282 struct led_classdev **dr;
285 dr = devres_alloc(devm_led_classdev_release, sizeof(*dr), GFP_KERNEL);
289 rc = led_classdev_register(parent, led_cdev);
296 devres_add(parent, dr);
300 EXPORT_SYMBOL_GPL(devm_led_classdev_register);
302 static int devm_led_classdev_match(struct device *dev, void *res, void *data)
304 struct led_cdev **p = res;
306 if (WARN_ON(!p || !*p))
313 * devm_led_classdev_unregister() - resource managed led_classdev_unregister()
314 * @parent: The device to unregister.
315 * @led_cdev: the led_classdev structure for this device.
317 void devm_led_classdev_unregister(struct device *dev,
318 struct led_classdev *led_cdev)
320 WARN_ON(devres_release(dev,
321 devm_led_classdev_release,
322 devm_led_classdev_match, led_cdev));
324 EXPORT_SYMBOL_GPL(devm_led_classdev_unregister);
326 static int __init leds_init(void)
328 leds_class = class_create(THIS_MODULE, "leds");
329 if (IS_ERR(leds_class))
330 return PTR_ERR(leds_class);
331 leds_class->pm = &leds_class_dev_pm_ops;
332 leds_class->dev_groups = led_groups;
336 static void __exit leds_exit(void)
338 class_destroy(leds_class);
341 subsys_initcall(leds_init);
342 module_exit(leds_exit);
344 MODULE_AUTHOR("John Lenz, Richard Purdie");
345 MODULE_LICENSE("GPL");
346 MODULE_DESCRIPTION("LED Class Interface");