tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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/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/ctype.h>
24#include <linux/leds.h>
25#include "leds.h"
26
27struct timer_trig_data {
28 unsigned long delay_on; /* milliseconds on */
29 unsigned long delay_off; /* milliseconds off */
30 struct timer_list timer;
31};
32
33static 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
55static 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
65static 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
87static 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
97static 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
119static CLASS_DEVICE_ATTR(delay_on, 0644, led_delay_on_show,
120 led_delay_on_store);
121static CLASS_DEVICE_ATTR(delay_off, 0644, led_delay_off_show,
122 led_delay_off_store);
123
124static void timer_trig_activate(struct led_classdev *led_cdev)
125{
126 struct timer_trig_data *timer_data;
127
128 timer_data = kzalloc(sizeof(struct timer_trig_data), GFP_KERNEL);
129 if (!timer_data)
130 return;
131
132 led_cdev->trigger_data = timer_data;
133
134 init_timer(&timer_data->timer);
135 timer_data->timer.function = led_timer_function;
136 timer_data->timer.data = (unsigned long) led_cdev;
137
138 class_device_create_file(led_cdev->class_dev,
139 &class_device_attr_delay_on);
140 class_device_create_file(led_cdev->class_dev,
141 &class_device_attr_delay_off);
142}
143
144static void timer_trig_deactivate(struct led_classdev *led_cdev)
145{
146 struct timer_trig_data *timer_data = led_cdev->trigger_data;
147
148 if (timer_data) {
149 class_device_remove_file(led_cdev->class_dev,
150 &class_device_attr_delay_on);
151 class_device_remove_file(led_cdev->class_dev,
152 &class_device_attr_delay_off);
153 del_timer_sync(&timer_data->timer);
154 kfree(timer_data);
155 }
156}
157
158static struct led_trigger timer_led_trigger = {
159 .name = "timer",
160 .activate = timer_trig_activate,
161 .deactivate = timer_trig_deactivate,
162};
163
164static int __init timer_trig_init(void)
165{
166 return led_trigger_register(&timer_led_trigger);
167}
168
169static void __exit timer_trig_exit(void)
170{
171 led_trigger_unregister(&timer_led_trigger);
172}
173
174module_init(timer_trig_init);
175module_exit(timer_trig_exit);
176
177MODULE_AUTHOR("Richard Purdie <rpurdie@openedhand.com>");
178MODULE_DESCRIPTION("Timer LED trigger");
179MODULE_LICENSE("GPL");