Return EPERM not ECHILD on security_task_wait failure
[linux-2.6] / drivers / leds / ledtrig-timer.c
1 /*
2  * LED Kernel Timer Trigger
3  *
4  * Copyright 2005-2006 Openedhand Ltd.
5  *
6  * Author: Richard Purdie <rpurdie@openedhand.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  *
12  */
13
14 #include <linux/module.h>
15 #include <linux/jiffies.h>
16 #include <linux/kernel.h>
17 #include <linux/init.h>
18 #include <linux/list.h>
19 #include <linux/spinlock.h>
20 #include <linux/device.h>
21 #include <linux/sysdev.h>
22 #include <linux/timer.h>
23 #include <linux/ctype.h>
24 #include <linux/leds.h>
25 #include "leds.h"
26
27 struct timer_trig_data {
28         unsigned long delay_on;         /* milliseconds on */
29         unsigned long delay_off;        /* milliseconds off */
30         struct timer_list timer;
31 };
32
33 static void led_timer_function(unsigned long data)
34 {
35         struct led_classdev *led_cdev = (struct led_classdev *) data;
36         struct timer_trig_data *timer_data = led_cdev->trigger_data;
37         unsigned long brightness = LED_OFF;
38         unsigned long delay = timer_data->delay_off;
39
40         if (!timer_data->delay_on || !timer_data->delay_off) {
41                 led_set_brightness(led_cdev, LED_OFF);
42                 return;
43         }
44
45         if (!led_cdev->brightness) {
46                 brightness = LED_FULL;
47                 delay = timer_data->delay_on;
48         }
49
50         led_set_brightness(led_cdev, brightness);
51
52         mod_timer(&timer_data->timer, jiffies + msecs_to_jiffies(delay));
53 }
54
55 static ssize_t led_delay_on_show(struct class_device *dev, char *buf)
56 {
57         struct led_classdev *led_cdev = class_get_devdata(dev);
58         struct timer_trig_data *timer_data = led_cdev->trigger_data;
59
60         sprintf(buf, "%lu\n", timer_data->delay_on);
61
62         return strlen(buf) + 1;
63 }
64
65 static ssize_t led_delay_on_store(struct class_device *dev, const char *buf,
66                                 size_t size)
67 {
68         struct led_classdev *led_cdev = class_get_devdata(dev);
69         struct timer_trig_data *timer_data = led_cdev->trigger_data;
70         int ret = -EINVAL;
71         char *after;
72         unsigned long state = simple_strtoul(buf, &after, 10);
73         size_t count = after - buf;
74
75         if (*after && isspace(*after))
76                 count++;
77
78         if (count == size) {
79                 timer_data->delay_on = state;
80                 mod_timer(&timer_data->timer, jiffies + 1);
81                 ret = count;
82         }
83
84         return ret;
85 }
86
87 static ssize_t led_delay_off_show(struct class_device *dev, char *buf)
88 {
89         struct led_classdev *led_cdev = class_get_devdata(dev);
90         struct timer_trig_data *timer_data = led_cdev->trigger_data;
91
92         sprintf(buf, "%lu\n", timer_data->delay_off);
93
94         return strlen(buf) + 1;
95 }
96
97 static ssize_t led_delay_off_store(struct class_device *dev, const char *buf,
98                                 size_t size)
99 {
100         struct led_classdev *led_cdev = class_get_devdata(dev);
101         struct timer_trig_data *timer_data = led_cdev->trigger_data;
102         int ret = -EINVAL;
103         char *after;
104         unsigned long state = simple_strtoul(buf, &after, 10);
105         size_t count = after - buf;
106
107         if (*after && isspace(*after))
108                 count++;
109
110         if (count == size) {
111                 timer_data->delay_off = state;
112                 mod_timer(&timer_data->timer, jiffies + 1);
113                 ret = count;
114         }
115
116         return ret;
117 }
118
119 static CLASS_DEVICE_ATTR(delay_on, 0644, led_delay_on_show,
120                         led_delay_on_store);
121 static CLASS_DEVICE_ATTR(delay_off, 0644, led_delay_off_show,
122                         led_delay_off_store);
123
124 static void timer_trig_activate(struct led_classdev *led_cdev)
125 {
126         struct timer_trig_data *timer_data;
127         int rc;
128
129         timer_data = kzalloc(sizeof(struct timer_trig_data), GFP_KERNEL);
130         if (!timer_data)
131                 return;
132
133         led_cdev->trigger_data = timer_data;
134
135         init_timer(&timer_data->timer);
136         timer_data->timer.function = led_timer_function;
137         timer_data->timer.data = (unsigned long) led_cdev;
138
139         rc = class_device_create_file(led_cdev->class_dev,
140                                 &class_device_attr_delay_on);
141         if (rc) goto err_out;
142         rc = class_device_create_file(led_cdev->class_dev,
143                                 &class_device_attr_delay_off);
144         if (rc) goto err_out_delayon;
145
146         return;
147
148 err_out_delayon:
149         class_device_remove_file(led_cdev->class_dev,
150                                 &class_device_attr_delay_on);
151 err_out:
152         led_cdev->trigger_data = NULL;
153         kfree(timer_data);
154 }
155
156 static void timer_trig_deactivate(struct led_classdev *led_cdev)
157 {
158         struct timer_trig_data *timer_data = led_cdev->trigger_data;
159
160         if (timer_data) {
161                 class_device_remove_file(led_cdev->class_dev,
162                                         &class_device_attr_delay_on);
163                 class_device_remove_file(led_cdev->class_dev,
164                                         &class_device_attr_delay_off);
165                 del_timer_sync(&timer_data->timer);
166                 kfree(timer_data);
167         }
168 }
169
170 static struct led_trigger timer_led_trigger = {
171         .name     = "timer",
172         .activate = timer_trig_activate,
173         .deactivate = timer_trig_deactivate,
174 };
175
176 static int __init timer_trig_init(void)
177 {
178         return led_trigger_register(&timer_led_trigger);
179 }
180
181 static void __exit timer_trig_exit(void)
182 {
183         led_trigger_unregister(&timer_led_trigger);
184 }
185
186 module_init(timer_trig_init);
187 module_exit(timer_trig_exit);
188
189 MODULE_AUTHOR("Richard Purdie <rpurdie@openedhand.com>");
190 MODULE_DESCRIPTION("Timer LED trigger");
191 MODULE_LICENSE("GPL");