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/config.h>
15 #include <linux/module.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/leds.h>
26 struct timer_trig_data {
27 unsigned long delay_on; /* milliseconds on */
28 unsigned long delay_off; /* milliseconds off */
29 struct timer_list timer;
32 static void led_timer_function(unsigned long data)
34 struct led_classdev *led_cdev = (struct led_classdev *) data;
35 struct timer_trig_data *timer_data = led_cdev->trigger_data;
36 unsigned long brightness = LED_OFF;
37 unsigned long delay = timer_data->delay_off;
39 if (!timer_data->delay_on || !timer_data->delay_off) {
40 led_set_brightness(led_cdev, LED_OFF);
44 if (!led_cdev->brightness) {
45 brightness = LED_FULL;
46 delay = timer_data->delay_on;
49 led_set_brightness(led_cdev, brightness);
51 mod_timer(&timer_data->timer, jiffies + msecs_to_jiffies(delay));
54 static ssize_t led_delay_on_show(struct class_device *dev, char *buf)
56 struct led_classdev *led_cdev = class_get_devdata(dev);
57 struct timer_trig_data *timer_data = led_cdev->trigger_data;
59 sprintf(buf, "%lu\n", timer_data->delay_on);
61 return strlen(buf) + 1;
64 static ssize_t led_delay_on_store(struct class_device *dev, const char *buf,
67 struct led_classdev *led_cdev = class_get_devdata(dev);
68 struct timer_trig_data *timer_data = led_cdev->trigger_data;
71 unsigned long state = simple_strtoul(buf, &after, 10);
73 if (after - buf > 0) {
74 timer_data->delay_on = state;
75 mod_timer(&timer_data->timer, jiffies + 1);
82 static ssize_t led_delay_off_show(struct class_device *dev, char *buf)
84 struct led_classdev *led_cdev = class_get_devdata(dev);
85 struct timer_trig_data *timer_data = led_cdev->trigger_data;
87 sprintf(buf, "%lu\n", timer_data->delay_off);
89 return strlen(buf) + 1;
92 static ssize_t led_delay_off_store(struct class_device *dev, const char *buf,
95 struct led_classdev *led_cdev = class_get_devdata(dev);
96 struct timer_trig_data *timer_data = led_cdev->trigger_data;
99 unsigned long state = simple_strtoul(buf, &after, 10);
101 if (after - buf > 0) {
102 timer_data->delay_off = state;
103 mod_timer(&timer_data->timer, jiffies + 1);
110 static CLASS_DEVICE_ATTR(delay_on, 0644, led_delay_on_show,
112 static CLASS_DEVICE_ATTR(delay_off, 0644, led_delay_off_show,
113 led_delay_off_store);
115 static void timer_trig_activate(struct led_classdev *led_cdev)
117 struct timer_trig_data *timer_data;
119 timer_data = kzalloc(sizeof(struct timer_trig_data), GFP_KERNEL);
123 led_cdev->trigger_data = timer_data;
125 init_timer(&timer_data->timer);
126 timer_data->timer.function = led_timer_function;
127 timer_data->timer.data = (unsigned long) led_cdev;
129 class_device_create_file(led_cdev->class_dev,
130 &class_device_attr_delay_on);
131 class_device_create_file(led_cdev->class_dev,
132 &class_device_attr_delay_off);
135 static void timer_trig_deactivate(struct led_classdev *led_cdev)
137 struct timer_trig_data *timer_data = led_cdev->trigger_data;
140 class_device_remove_file(led_cdev->class_dev,
141 &class_device_attr_delay_on);
142 class_device_remove_file(led_cdev->class_dev,
143 &class_device_attr_delay_off);
144 del_timer_sync(&timer_data->timer);
149 static struct led_trigger timer_led_trigger = {
151 .activate = timer_trig_activate,
152 .deactivate = timer_trig_deactivate,
155 static int __init timer_trig_init(void)
157 return led_trigger_register(&timer_led_trigger);
160 static void __exit timer_trig_exit(void)
162 led_trigger_unregister(&timer_led_trigger);
165 module_init(timer_trig_init);
166 module_exit(timer_trig_exit);
168 MODULE_AUTHOR("Richard Purdie <rpurdie@openedhand.com>");
169 MODULE_DESCRIPTION("Timer LED trigger");
170 MODULE_LICENSE("GPL");