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/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
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 device *dev,
56 struct device_attribute *attr, char *buf)
57{
58 struct led_classdev *led_cdev = dev_get_drvdata(dev);
59 struct timer_trig_data *timer_data = led_cdev->trigger_data;
60
61 sprintf(buf, "%lu\n", timer_data->delay_on);
62
63 return strlen(buf) + 1;
64}
65
66static ssize_t led_delay_on_store(struct device *dev,
67 struct device_attribute *attr, const char *buf, size_t size)
68{
69 struct led_classdev *led_cdev = dev_get_drvdata(dev);
70 struct timer_trig_data *timer_data = led_cdev->trigger_data;
71 int ret = -EINVAL;
72 char *after;
73 unsigned long state = simple_strtoul(buf, &after, 10);
74 size_t count = after - buf;
75
76 if (*after && isspace(*after))
77 count++;
78
79 if (count == size) {
80 timer_data->delay_on = state;
81 mod_timer(&timer_data->timer, jiffies + 1);
82 ret = count;
83 }
84
85 return ret;
86}
87
88static ssize_t led_delay_off_show(struct device *dev,
89 struct device_attribute *attr, char *buf)
90{
91 struct led_classdev *led_cdev = dev_get_drvdata(dev);
92 struct timer_trig_data *timer_data = led_cdev->trigger_data;
93
94 sprintf(buf, "%lu\n", timer_data->delay_off);
95
96 return strlen(buf) + 1;
97}
98
99static ssize_t led_delay_off_store(struct device *dev,
100 struct device_attribute *attr, const char *buf, size_t size)
101{
102 struct led_classdev *led_cdev = dev_get_drvdata(dev);
103 struct timer_trig_data *timer_data = led_cdev->trigger_data;
104 int ret = -EINVAL;
105 char *after;
106 unsigned long state = simple_strtoul(buf, &after, 10);
107 size_t count = after - buf;
108
109 if (*after && isspace(*after))
110 count++;
111
112 if (count == size) {
113 timer_data->delay_off = state;
114 mod_timer(&timer_data->timer, jiffies + 1);
115 ret = count;
116 }
117
118 return ret;
119}
120
121static DEVICE_ATTR(delay_on, 0644, led_delay_on_show, led_delay_on_store);
122static DEVICE_ATTR(delay_off, 0644, led_delay_off_show, led_delay_off_store);
123
124static 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 = device_create_file(led_cdev->dev, &dev_attr_delay_on);
140 if (rc)
141 goto err_out;
142 rc = device_create_file(led_cdev->dev, &dev_attr_delay_off);
143 if (rc)
144 goto err_out_delayon;
145
146 return;
147
148err_out_delayon:
149 device_remove_file(led_cdev->dev, &dev_attr_delay_on);
150err_out:
151 led_cdev->trigger_data = NULL;
152 kfree(timer_data);
153}
154
155static void timer_trig_deactivate(struct led_classdev *led_cdev)
156{
157 struct timer_trig_data *timer_data = led_cdev->trigger_data;
158
159 if (timer_data) {
160 device_remove_file(led_cdev->dev, &dev_attr_delay_on);
161 device_remove_file(led_cdev->dev, &dev_attr_delay_off);
162 del_timer_sync(&timer_data->timer);
163 kfree(timer_data);
164 }
165}
166
167static struct led_trigger timer_led_trigger = {
168 .name = "timer",
169 .activate = timer_trig_activate,
170 .deactivate = timer_trig_deactivate,
171};
172
173static int __init timer_trig_init(void)
174{
175 return led_trigger_register(&timer_led_trigger);
176}
177
178static void __exit timer_trig_exit(void)
179{
180 led_trigger_unregister(&timer_led_trigger);
181}
182
183module_init(timer_trig_init);
184module_exit(timer_trig_exit);
185
186MODULE_AUTHOR("Richard Purdie <rpurdie@openedhand.com>");
187MODULE_DESCRIPTION("Timer LED trigger");
188MODULE_LICENSE("GPL");