Commit | Line | Data |
---|---|---|
c3bc9956 RP |
1 | /* |
2 | * LED Triggers Core | |
3 | * | |
f8a7c6fe | 4 | * Copyright 2005-2007 Openedhand Ltd. |
c3bc9956 RP |
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 | ||
c3bc9956 RP |
14 | #include <linux/module.h> |
15 | #include <linux/kernel.h> | |
16 | #include <linux/init.h> | |
17 | #include <linux/list.h> | |
18 | #include <linux/spinlock.h> | |
19 | #include <linux/device.h> | |
20 | #include <linux/sysdev.h> | |
21 | #include <linux/timer.h> | |
dc47206e | 22 | #include <linux/rwsem.h> |
c3bc9956 RP |
23 | #include <linux/leds.h> |
24 | #include "leds.h" | |
25 | ||
26 | /* | |
27 | * Nests outside led_cdev->trigger_lock | |
28 | */ | |
dc47206e | 29 | static DECLARE_RWSEM(triggers_list_lock); |
c3bc9956 RP |
30 | static LIST_HEAD(trigger_list); |
31 | ||
f8a7c6fe RP |
32 | ssize_t led_trigger_store(struct device *dev, struct device_attribute *attr, |
33 | const char *buf, size_t count) | |
c3bc9956 | 34 | { |
f8a7c6fe | 35 | struct led_classdev *led_cdev = dev_get_drvdata(dev); |
c3bc9956 RP |
36 | char trigger_name[TRIG_NAME_MAX]; |
37 | struct led_trigger *trig; | |
38 | size_t len; | |
39 | ||
40 | trigger_name[sizeof(trigger_name) - 1] = '\0'; | |
41 | strncpy(trigger_name, buf, sizeof(trigger_name) - 1); | |
42 | len = strlen(trigger_name); | |
43 | ||
44 | if (len && trigger_name[len - 1] == '\n') | |
45 | trigger_name[len - 1] = '\0'; | |
46 | ||
47 | if (!strcmp(trigger_name, "none")) { | |
0013b23d | 48 | led_trigger_remove(led_cdev); |
c3bc9956 RP |
49 | return count; |
50 | } | |
51 | ||
dc47206e | 52 | down_read(&triggers_list_lock); |
c3bc9956 RP |
53 | list_for_each_entry(trig, &trigger_list, next_trig) { |
54 | if (!strcmp(trigger_name, trig->name)) { | |
dc47206e | 55 | down_write(&led_cdev->trigger_lock); |
c3bc9956 | 56 | led_trigger_set(led_cdev, trig); |
dc47206e | 57 | up_write(&led_cdev->trigger_lock); |
c3bc9956 | 58 | |
dc47206e | 59 | up_read(&triggers_list_lock); |
c3bc9956 RP |
60 | return count; |
61 | } | |
62 | } | |
dc47206e | 63 | up_read(&triggers_list_lock); |
c3bc9956 RP |
64 | |
65 | return -EINVAL; | |
66 | } | |
67 | ||
68 | ||
f8a7c6fe RP |
69 | ssize_t led_trigger_show(struct device *dev, struct device_attribute *attr, |
70 | char *buf) | |
c3bc9956 | 71 | { |
f8a7c6fe | 72 | struct led_classdev *led_cdev = dev_get_drvdata(dev); |
c3bc9956 RP |
73 | struct led_trigger *trig; |
74 | int len = 0; | |
75 | ||
dc47206e RP |
76 | down_read(&triggers_list_lock); |
77 | down_read(&led_cdev->trigger_lock); | |
c3bc9956 RP |
78 | |
79 | if (!led_cdev->trigger) | |
80 | len += sprintf(buf+len, "[none] "); | |
81 | else | |
82 | len += sprintf(buf+len, "none "); | |
83 | ||
84 | list_for_each_entry(trig, &trigger_list, next_trig) { | |
85 | if (led_cdev->trigger && !strcmp(led_cdev->trigger->name, | |
86 | trig->name)) | |
87 | len += sprintf(buf+len, "[%s] ", trig->name); | |
88 | else | |
89 | len += sprintf(buf+len, "%s ", trig->name); | |
90 | } | |
dc47206e RP |
91 | up_read(&led_cdev->trigger_lock); |
92 | up_read(&triggers_list_lock); | |
c3bc9956 RP |
93 | |
94 | len += sprintf(len+buf, "\n"); | |
95 | return len; | |
96 | } | |
97 | ||
98 | void led_trigger_event(struct led_trigger *trigger, | |
99 | enum led_brightness brightness) | |
100 | { | |
101 | struct list_head *entry; | |
102 | ||
103 | if (!trigger) | |
104 | return; | |
105 | ||
106 | read_lock(&trigger->leddev_list_lock); | |
107 | list_for_each(entry, &trigger->led_cdevs) { | |
108 | struct led_classdev *led_cdev; | |
109 | ||
110 | led_cdev = list_entry(entry, struct led_classdev, trig_list); | |
111 | led_set_brightness(led_cdev, brightness); | |
112 | } | |
113 | read_unlock(&trigger->leddev_list_lock); | |
114 | } | |
115 | ||
116 | /* Caller must ensure led_cdev->trigger_lock held */ | |
117 | void led_trigger_set(struct led_classdev *led_cdev, struct led_trigger *trigger) | |
118 | { | |
119 | unsigned long flags; | |
120 | ||
121 | /* Remove any existing trigger */ | |
122 | if (led_cdev->trigger) { | |
123 | write_lock_irqsave(&led_cdev->trigger->leddev_list_lock, flags); | |
124 | list_del(&led_cdev->trig_list); | |
125 | write_unlock_irqrestore(&led_cdev->trigger->leddev_list_lock, flags); | |
126 | if (led_cdev->trigger->deactivate) | |
127 | led_cdev->trigger->deactivate(led_cdev); | |
e3e5fc91 | 128 | led_set_brightness(led_cdev, LED_OFF); |
c3bc9956 RP |
129 | } |
130 | if (trigger) { | |
131 | write_lock_irqsave(&trigger->leddev_list_lock, flags); | |
132 | list_add_tail(&led_cdev->trig_list, &trigger->led_cdevs); | |
133 | write_unlock_irqrestore(&trigger->leddev_list_lock, flags); | |
134 | if (trigger->activate) | |
135 | trigger->activate(led_cdev); | |
136 | } | |
137 | led_cdev->trigger = trigger; | |
138 | } | |
139 | ||
0013b23d NM |
140 | void led_trigger_remove(struct led_classdev *led_cdev) |
141 | { | |
142 | down_write(&led_cdev->trigger_lock); | |
143 | led_trigger_set(led_cdev, NULL); | |
144 | up_write(&led_cdev->trigger_lock); | |
145 | } | |
146 | ||
c3bc9956 RP |
147 | void led_trigger_set_default(struct led_classdev *led_cdev) |
148 | { | |
149 | struct led_trigger *trig; | |
150 | ||
151 | if (!led_cdev->default_trigger) | |
152 | return; | |
153 | ||
dc47206e RP |
154 | down_read(&triggers_list_lock); |
155 | down_write(&led_cdev->trigger_lock); | |
c3bc9956 RP |
156 | list_for_each_entry(trig, &trigger_list, next_trig) { |
157 | if (!strcmp(led_cdev->default_trigger, trig->name)) | |
158 | led_trigger_set(led_cdev, trig); | |
159 | } | |
dc47206e RP |
160 | up_write(&led_cdev->trigger_lock); |
161 | up_read(&triggers_list_lock); | |
c3bc9956 RP |
162 | } |
163 | ||
164 | int led_trigger_register(struct led_trigger *trigger) | |
165 | { | |
166 | struct led_classdev *led_cdev; | |
167 | ||
168 | rwlock_init(&trigger->leddev_list_lock); | |
169 | INIT_LIST_HEAD(&trigger->led_cdevs); | |
170 | ||
171 | /* Add to the list of led triggers */ | |
dc47206e | 172 | down_write(&triggers_list_lock); |
c3bc9956 | 173 | list_add_tail(&trigger->next_trig, &trigger_list); |
dc47206e | 174 | up_write(&triggers_list_lock); |
c3bc9956 RP |
175 | |
176 | /* Register with any LEDs that have this as a default trigger */ | |
72f8da32 | 177 | down_read(&leds_list_lock); |
c3bc9956 | 178 | list_for_each_entry(led_cdev, &leds_list, node) { |
dc47206e | 179 | down_write(&led_cdev->trigger_lock); |
c3bc9956 RP |
180 | if (!led_cdev->trigger && led_cdev->default_trigger && |
181 | !strcmp(led_cdev->default_trigger, trigger->name)) | |
182 | led_trigger_set(led_cdev, trigger); | |
dc47206e | 183 | up_write(&led_cdev->trigger_lock); |
c3bc9956 | 184 | } |
72f8da32 | 185 | up_read(&leds_list_lock); |
c3bc9956 RP |
186 | |
187 | return 0; | |
188 | } | |
189 | ||
190 | void led_trigger_register_simple(const char *name, struct led_trigger **tp) | |
191 | { | |
192 | struct led_trigger *trigger; | |
e3986f63 | 193 | int err; |
c3bc9956 RP |
194 | |
195 | trigger = kzalloc(sizeof(struct led_trigger), GFP_KERNEL); | |
196 | ||
197 | if (trigger) { | |
198 | trigger->name = name; | |
e3986f63 RP |
199 | err = led_trigger_register(trigger); |
200 | if (err < 0) | |
201 | printk(KERN_WARNING "LED trigger %s failed to register" | |
202 | " (%d)\n", name, err); | |
203 | } else | |
204 | printk(KERN_WARNING "LED trigger %s failed to register" | |
205 | " (no memory)\n", name); | |
206 | ||
c3bc9956 RP |
207 | *tp = trigger; |
208 | } | |
209 | ||
210 | void led_trigger_unregister(struct led_trigger *trigger) | |
211 | { | |
212 | struct led_classdev *led_cdev; | |
213 | ||
214 | /* Remove from the list of led triggers */ | |
dc47206e | 215 | down_write(&triggers_list_lock); |
c3bc9956 | 216 | list_del(&trigger->next_trig); |
dc47206e | 217 | up_write(&triggers_list_lock); |
c3bc9956 RP |
218 | |
219 | /* Remove anyone actively using this trigger */ | |
72f8da32 | 220 | down_read(&leds_list_lock); |
c3bc9956 | 221 | list_for_each_entry(led_cdev, &leds_list, node) { |
dc47206e | 222 | down_write(&led_cdev->trigger_lock); |
c3bc9956 RP |
223 | if (led_cdev->trigger == trigger) |
224 | led_trigger_set(led_cdev, NULL); | |
dc47206e | 225 | up_write(&led_cdev->trigger_lock); |
c3bc9956 | 226 | } |
72f8da32 | 227 | up_read(&leds_list_lock); |
c3bc9956 RP |
228 | } |
229 | ||
230 | void led_trigger_unregister_simple(struct led_trigger *trigger) | |
231 | { | |
3593a6d6 RP |
232 | if (trigger) |
233 | led_trigger_unregister(trigger); | |
c3bc9956 RP |
234 | kfree(trigger); |
235 | } | |
236 | ||
237 | /* Used by LED Class */ | |
238 | EXPORT_SYMBOL_GPL(led_trigger_set); | |
0013b23d | 239 | EXPORT_SYMBOL_GPL(led_trigger_remove); |
c3bc9956 RP |
240 | EXPORT_SYMBOL_GPL(led_trigger_set_default); |
241 | EXPORT_SYMBOL_GPL(led_trigger_show); | |
242 | EXPORT_SYMBOL_GPL(led_trigger_store); | |
243 | ||
244 | /* LED Trigger Interface */ | |
245 | EXPORT_SYMBOL_GPL(led_trigger_register); | |
246 | EXPORT_SYMBOL_GPL(led_trigger_unregister); | |
247 | ||
248 | /* Simple LED Tigger Interface */ | |
249 | EXPORT_SYMBOL_GPL(led_trigger_register_simple); | |
250 | EXPORT_SYMBOL_GPL(led_trigger_unregister_simple); | |
251 | EXPORT_SYMBOL_GPL(led_trigger_event); | |
252 | ||
253 | MODULE_AUTHOR("Richard Purdie"); | |
254 | MODULE_LICENSE("GPL"); | |
255 | MODULE_DESCRIPTION("LED Triggers Core"); |