1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
|
/*
* LED Kernel Timer Trigger
*
* Copyright 2005-2006 Openedhand Ltd.
*
* Author: Richard Purdie <rpurdie@openedhand.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
*/
#include <linux/module.h>
#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/spinlock.h>
#include <linux/device.h>
#include <linux/sysdev.h>
#include <linux/timer.h>
#include <linux/ctype.h>
#include <linux/leds.h>
#include "leds.h"
struct timer_trig_data {
int brightness_on; /* LED brightness during "on" period.
* (LED_OFF < brightness_on <= LED_FULL)
*/
unsigned long delay_on; /* milliseconds on */
unsigned long delay_off; /* milliseconds off */
struct timer_list timer;
};
static void led_timer_function(unsigned long data)
{
struct led_classdev *led_cdev = (struct led_classdev *) data;
struct timer_trig_data *timer_data = led_cdev->trigger_data;
unsigned long brightness;
unsigned long delay;
if (!timer_data->delay_on || !timer_data->delay_off) {
led_set_brightness(led_cdev, LED_OFF);
return;
}
brightness = led_get_brightness(led_cdev);
if (!brightness) {
/* Time to switch the LED on. */
brightness = timer_data->brightness_on;
delay = timer_data->delay_on;
} else {
/* Store the current brightness value to be able
* to restore it when the delay_off period is over.
*/
timer_data->brightness_on = brightness;
brightness = LED_OFF;
delay = timer_data->delay_off;
}
led_set_brightness(led_cdev, brightness);
mod_timer(&timer_data->timer, jiffies + msecs_to_jiffies(delay));
}
static ssize_t led_delay_on_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct timer_trig_data *timer_data = led_cdev->trigger_data;
return sprintf(buf, "%lu\n", timer_data->delay_on);
}
static ssize_t led_delay_on_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t size)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct timer_trig_data *timer_data = led_cdev->trigger_data;
int ret = -EINVAL;
char *after;
unsigned long state = simple_strtoul(buf, &after, 10);
size_t count = after - buf;
if (*after && isspace(*after))
count++;
if (count == size) {
if (timer_data->delay_on != state) {
/* the new value differs from the previous */
timer_data->delay_on = state;
/* deactivate previous settings */
del_timer_sync(&timer_data->timer);
/* try to activate hardware acceleration, if any */
if (!led_cdev->blink_set ||
led_cdev->blink_set(led_cdev,
&timer_data->delay_on, &timer_data->delay_off)) {
/* no hardware acceleration, blink via timer */
mod_timer(&timer_data->timer, jiffies + 1);
}
}
ret = count;
}
return ret;
}
static ssize_t led_delay_off_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct timer_trig_data *timer_data = led_cdev->trigger_data;
return sprintf(buf, "%lu\n", timer_data->delay_off);
}
static ssize_t led_delay_off_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t size)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct timer_trig_data *timer_data = led_cdev->trigger_data;
int ret = -EINVAL;
char *after;
unsigned long state = simple_strtoul(buf, &after, 10);
size_t count = after - buf;
if (*after && isspace(*after))
count++;
if (count == size) {
if (timer_data->delay_off != state) {
/* the new value differs from the previous */
timer_data->delay_off = state;
/* deactivate previous settings */
del_timer_sync(&timer_data->timer);
/* try to activate hardware acceleration, if any */
if (!led_cdev->blink_set ||
led_cdev->blink_set(led_cdev,
&timer_data->delay_on, &timer_data->delay_off)) {
/* no hardware acceleration, blink via timer */
mod_timer(&timer_data->timer, jiffies + 1);
}
}
ret = count;
}
return ret;
}
static DEVICE_ATTR(delay_on, 0644, led_delay_on_show, led_delay_on_store);
static DEVICE_ATTR(delay_off, 0644, led_delay_off_show, led_delay_off_store);
static void timer_trig_activate(struct led_classdev *led_cdev)
{
struct timer_trig_data *timer_data;
int rc;
timer_data = kzalloc(sizeof(struct timer_trig_data), GFP_KERNEL);
if (!timer_data)
return;
timer_data->brightness_on = led_get_brightness(led_cdev);
if (timer_data->brightness_on == LED_OFF)
timer_data->brightness_on = led_cdev->max_brightness;
led_cdev->trigger_data = timer_data;
init_timer(&timer_data->timer);
timer_data->timer.function = led_timer_function;
timer_data->timer.data = (unsigned long) led_cdev;
rc = device_create_file(led_cdev->dev, &dev_attr_delay_on);
if (rc)
goto err_out;
rc = device_create_file(led_cdev->dev, &dev_attr_delay_off);
if (rc)
goto err_out_delayon;
/* If there is hardware support for blinking, start one
* user friendly blink rate chosen by the driver.
*/
if (led_cdev->blink_set)
led_cdev->blink_set(led_cdev,
&timer_data->delay_on, &timer_data->delay_off);
return;
err_out_delayon:
device_remove_file(led_cdev->dev, &dev_attr_delay_on);
err_out:
led_cdev->trigger_data = NULL;
kfree(timer_data);
}
static void timer_trig_deactivate(struct led_classdev *led_cdev)
{
struct timer_trig_data *timer_data = led_cdev->trigger_data;
unsigned long on = 0, off = 0;
if (timer_data) {
device_remove_file(led_cdev->dev, &dev_attr_delay_on);
device_remove_file(led_cdev->dev, &dev_attr_delay_off);
del_timer_sync(&timer_data->timer);
kfree(timer_data);
}
/* If there is hardware support for blinking, stop it */
if (led_cdev->blink_set)
led_cdev->blink_set(led_cdev, &on, &off);
}
static struct led_trigger timer_led_trigger = {
.name = "timer",
.activate = timer_trig_activate,
.deactivate = timer_trig_deactivate,
};
static int __init timer_trig_init(void)
{
return led_trigger_register(&timer_led_trigger);
}
static void __exit timer_trig_exit(void)
{
led_trigger_unregister(&timer_led_trigger);
}
module_init(timer_trig_init);
module_exit(timer_trig_exit);
MODULE_AUTHOR("Richard Purdie <rpurdie@openedhand.com>");
MODULE_DESCRIPTION("Timer LED trigger");
MODULE_LICENSE("GPL");
|
