fix file specification in comments
[linux-2.6.git] / drivers / leds / led-class.c
1 /*
2  * LED Class Core
3  *
4  * Copyright (C) 2005 John Lenz <lenz@cs.wisc.edu>
5  * Copyright (C) 2005-2006 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
25 static struct class *leds_class;
26
27 static ssize_t led_brightness_show(struct class_device *dev, char *buf)
28 {
29         struct led_classdev *led_cdev = class_get_devdata(dev);
30         ssize_t ret = 0;
31
32         /* no lock needed for this */
33         sprintf(buf, "%u\n", led_cdev->brightness);
34         ret = strlen(buf) + 1;
35
36         return ret;
37 }
38
39 static ssize_t led_brightness_store(struct class_device *dev,
40                                 const char *buf, size_t size)
41 {
42         struct led_classdev *led_cdev = class_get_devdata(dev);
43         ssize_t ret = -EINVAL;
44         char *after;
45         unsigned long state = simple_strtoul(buf, &after, 10);
46         size_t count = after - buf;
47
48         if (*after && isspace(*after))
49                 count++;
50
51         if (count == size) {
52                 ret = count;
53                 led_set_brightness(led_cdev, state);
54         }
55
56         return ret;
57 }
58
59 static CLASS_DEVICE_ATTR(brightness, 0644, led_brightness_show,
60                         led_brightness_store);
61 #ifdef CONFIG_LEDS_TRIGGERS
62 static CLASS_DEVICE_ATTR(trigger, 0644, led_trigger_show, led_trigger_store);
63 #endif
64
65 /**
66  * led_classdev_suspend - suspend an led_classdev.
67  * @led_cdev: the led_classdev to suspend.
68  */
69 void led_classdev_suspend(struct led_classdev *led_cdev)
70 {
71         led_cdev->flags |= LED_SUSPENDED;
72         led_cdev->brightness_set(led_cdev, 0);
73 }
74 EXPORT_SYMBOL_GPL(led_classdev_suspend);
75
76 /**
77  * led_classdev_resume - resume an led_classdev.
78  * @led_cdev: the led_classdev to resume.
79  */
80 void led_classdev_resume(struct led_classdev *led_cdev)
81 {
82         led_cdev->brightness_set(led_cdev, led_cdev->brightness);
83         led_cdev->flags &= ~LED_SUSPENDED;
84 }
85 EXPORT_SYMBOL_GPL(led_classdev_resume);
86
87 /**
88  * led_classdev_register - register a new object of led_classdev class.
89  * @dev: The device to register.
90  * @led_cdev: the led_classdev structure for this device.
91  */
92 int led_classdev_register(struct device *parent, struct led_classdev *led_cdev)
93 {
94         led_cdev->class_dev = class_device_create(leds_class, NULL, 0,
95                                                 parent, "%s", led_cdev->name);
96         if (unlikely(IS_ERR(led_cdev->class_dev)))
97                 return PTR_ERR(led_cdev->class_dev);
98
99         class_set_devdata(led_cdev->class_dev, led_cdev);
100
101         /* register the attributes */
102         class_device_create_file(led_cdev->class_dev,
103                                 &class_device_attr_brightness);
104
105         /* add to the list of leds */
106         write_lock(&leds_list_lock);
107         list_add_tail(&led_cdev->node, &leds_list);
108         write_unlock(&leds_list_lock);
109
110 #ifdef CONFIG_LEDS_TRIGGERS
111         rwlock_init(&led_cdev->trigger_lock);
112
113         led_trigger_set_default(led_cdev);
114
115         class_device_create_file(led_cdev->class_dev,
116                                 &class_device_attr_trigger);
117 #endif
118
119         printk(KERN_INFO "Registered led device: %s\n",
120                         led_cdev->class_dev->class_id);
121
122         return 0;
123 }
124 EXPORT_SYMBOL_GPL(led_classdev_register);
125
126 /**
127  * led_classdev_unregister - unregisters a object of led_properties class.
128  * @led_cdev: the led device to unreigister
129  *
130  * Unregisters a previously registered via led_classdev_register object.
131  */
132 void led_classdev_unregister(struct led_classdev *led_cdev)
133 {
134         class_device_remove_file(led_cdev->class_dev,
135                                 &class_device_attr_brightness);
136 #ifdef CONFIG_LEDS_TRIGGERS
137         class_device_remove_file(led_cdev->class_dev,
138                                 &class_device_attr_trigger);
139         write_lock(&led_cdev->trigger_lock);
140         if (led_cdev->trigger)
141                 led_trigger_set(led_cdev, NULL);
142         write_unlock(&led_cdev->trigger_lock);
143 #endif
144
145         class_device_unregister(led_cdev->class_dev);
146
147         write_lock(&leds_list_lock);
148         list_del(&led_cdev->node);
149         write_unlock(&leds_list_lock);
150 }
151 EXPORT_SYMBOL_GPL(led_classdev_unregister);
152
153 static int __init leds_init(void)
154 {
155         leds_class = class_create(THIS_MODULE, "leds");
156         if (IS_ERR(leds_class))
157                 return PTR_ERR(leds_class);
158         return 0;
159 }
160
161 static void __exit leds_exit(void)
162 {
163         class_destroy(leds_class);
164 }
165
166 subsys_initcall(leds_init);
167 module_exit(leds_exit);
168
169 MODULE_AUTHOR("John Lenz, Richard Purdie");
170 MODULE_LICENSE("GPL");
171 MODULE_DESCRIPTION("LED Class Interface");