2 * LED Kernel Timer Trigger
4 * Copyright 2005-2006 Openedhand Ltd.
6 * Author: Richard Purdie <rpurdie@openedhand.com>
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.
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>
27 struct timer_trig_data {
28 unsigned long delay_on; /* milliseconds on */
29 unsigned long delay_off; /* milliseconds off */
30 struct timer_list timer;
33 static void led_timer_function(unsigned long data)
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;
40 if (!timer_data->delay_on || !timer_data->delay_off) {
41 led_set_brightness(led_cdev, LED_OFF);
45 if (!led_cdev->brightness) {
46 brightness = LED_FULL;
47 delay = timer_data->delay_on;
50 led_set_brightness(led_cdev, brightness);
52 mod_timer(&timer_data->timer, jiffies + msecs_to_jiffies(delay));
55 static ssize_t led_delay_on_show(struct class_device *dev, char *buf)
57 struct led_classdev *led_cdev = class_get_devdata(dev);
58 struct timer_trig_data *timer_data = led_cdev->trigger_data;
60 sprintf(buf, "%lu\n", timer_data->delay_on);
62 return strlen(buf) + 1;
65 static ssize_t led_delay_on_store(struct class_device *dev, const char *buf,
68 struct led_classdev *led_cdev = class_get_devdata(dev);
69 struct timer_trig_data *timer_data = led_cdev->trigger_data;
72 unsigned long state = simple_strtoul(buf, &after, 10);
73 size_t count = after - buf;
75 if (*after && isspace(*after))
79 timer_data->delay_on = state;
80 mod_timer(&timer_data->timer, jiffies + 1);
87 static ssize_t led_delay_off_show(struct class_device *dev, char *buf)
89 struct led_classdev *led_cdev = class_get_devdata(dev);
90 struct timer_trig_data *timer_data = led_cdev->trigger_data;
92 sprintf(buf, "%lu\n", timer_data->delay_off);
94 return strlen(buf) + 1;
97 static ssize_t led_delay_off_store(struct class_device *dev, const char *buf,
100 struct led_classdev *led_cdev = class_get_devdata(dev);
101 struct timer_trig_data *timer_data = led_cdev->trigger_data;
104 unsigned long state = simple_strtoul(buf, &after, 10);
105 size_t count = after - buf;
107 if (*after && isspace(*after))
111 timer_data->delay_off = state;
112 mod_timer(&timer_data->timer, jiffies + 1);
119 static CLASS_DEVICE_ATTR(delay_on, 0644, led_delay_on_show,
121 static CLASS_DEVICE_ATTR(delay_off, 0644, led_delay_off_show,
122 led_delay_off_store);
124 static void timer_trig_activate(struct led_classdev *led_cdev)
126 struct timer_trig_data *timer_data;
129 timer_data = kzalloc(sizeof(struct timer_trig_data), GFP_KERNEL);
133 led_cdev->trigger_data = timer_data;
135 init_timer(&timer_data->timer);
136 timer_data->timer.function = led_timer_function;
137 timer_data->timer.data = (unsigned long) led_cdev;
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;
149 class_device_remove_file(led_cdev->class_dev,
150 &class_device_attr_delay_on);
152 led_cdev->trigger_data = NULL;
156 static void timer_trig_deactivate(struct led_classdev *led_cdev)
158 struct timer_trig_data *timer_data = led_cdev->trigger_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);
170 static struct led_trigger timer_led_trigger = {
172 .activate = timer_trig_activate,
173 .deactivate = timer_trig_deactivate,
176 static int __init timer_trig_init(void)
178 return led_trigger_register(&timer_led_trigger);
181 static void __exit timer_trig_exit(void)
183 led_trigger_unregister(&timer_led_trigger);
186 module_init(timer_trig_init);
187 module_exit(timer_trig_exit);
189 MODULE_AUTHOR("Richard Purdie <rpurdie@openedhand.com>");
190 MODULE_DESCRIPTION("Timer LED trigger");
191 MODULE_LICENSE("GPL");