4 * Copyright (C) 2005 John Lenz <lenz@cs.wisc.edu>
5 * Copyright (C) 2005-2006 Richard Purdie <rpurdie@openedhand.com>
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/config.h>
13 #include <linux/module.h>
14 #include <linux/kernel.h>
15 #include <linux/init.h>
16 #include <linux/list.h>
17 #include <linux/spinlock.h>
18 #include <linux/device.h>
19 #include <linux/sysdev.h>
20 #include <linux/timer.h>
21 #include <linux/err.h>
22 #include <linux/leds.h>
25 static struct class *leds_class;
27 static ssize_t led_brightness_show(struct class_device *dev, char *buf)
29 struct led_classdev *led_cdev = class_get_devdata(dev);
32 /* no lock needed for this */
33 sprintf(buf, "%u\n", led_cdev->brightness);
34 ret = strlen(buf) + 1;
39 static ssize_t led_brightness_store(struct class_device *dev,
40 const char *buf, size_t size)
42 struct led_classdev *led_cdev = class_get_devdata(dev);
43 ssize_t ret = -EINVAL;
45 unsigned long state = simple_strtoul(buf, &after, 10);
47 if (after - buf > 0) {
49 led_set_brightness(led_cdev, state);
55 static CLASS_DEVICE_ATTR(brightness, 0644, led_brightness_show,
56 led_brightness_store);
59 * led_classdev_suspend - suspend an led_classdev.
60 * @led_cdev: the led_classdev to suspend.
62 void led_classdev_suspend(struct led_classdev *led_cdev)
64 led_cdev->flags |= LED_SUSPENDED;
65 led_cdev->brightness_set(led_cdev, 0);
67 EXPORT_SYMBOL_GPL(led_classdev_suspend);
70 * led_classdev_resume - resume an led_classdev.
71 * @led_cdev: the led_classdev to resume.
73 void led_classdev_resume(struct led_classdev *led_cdev)
75 led_cdev->brightness_set(led_cdev, led_cdev->brightness);
76 led_cdev->flags &= ~LED_SUSPENDED;
78 EXPORT_SYMBOL_GPL(led_classdev_resume);
81 * led_classdev_register - register a new object of led_classdev class.
82 * @dev: The device to register.
83 * @led_cdev: the led_classdev structure for this device.
85 int led_classdev_register(struct device *parent, struct led_classdev *led_cdev)
87 led_cdev->class_dev = class_device_create(leds_class, NULL, 0,
88 parent, "%s", led_cdev->name);
89 if (unlikely(IS_ERR(led_cdev->class_dev)))
90 return PTR_ERR(led_cdev->class_dev);
92 class_set_devdata(led_cdev->class_dev, led_cdev);
94 /* register the attributes */
95 class_device_create_file(led_cdev->class_dev,
96 &class_device_attr_brightness);
98 /* add to the list of leds */
99 write_lock(&leds_list_lock);
100 list_add_tail(&led_cdev->node, &leds_list);
101 write_unlock(&leds_list_lock);
103 printk(KERN_INFO "Registered led device: %s\n",
104 led_cdev->class_dev->class_id);
108 EXPORT_SYMBOL_GPL(led_classdev_register);
111 * led_classdev_unregister - unregisters a object of led_properties class.
112 * @led_cdev: the led device to unreigister
114 * Unregisters a previously registered via led_classdev_register object.
116 void led_classdev_unregister(struct led_classdev *led_cdev)
118 class_device_remove_file(led_cdev->class_dev,
119 &class_device_attr_brightness);
121 class_device_unregister(led_cdev->class_dev);
123 write_lock(&leds_list_lock);
124 list_del(&led_cdev->node);
125 write_unlock(&leds_list_lock);
127 EXPORT_SYMBOL_GPL(led_classdev_unregister);
129 static int __init leds_init(void)
131 leds_class = class_create(THIS_MODULE, "leds");
132 if (IS_ERR(leds_class))
133 return PTR_ERR(leds_class);
137 static void __exit leds_exit(void)
139 class_destroy(leds_class);
142 subsys_initcall(leds_init);
143 module_exit(leds_exit);
145 MODULE_AUTHOR("John Lenz, Richard Purdie");
146 MODULE_LICENSE("GPL");
147 MODULE_DESCRIPTION("LED Class Interface");