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Richard Purdiec3bc9952006-03-31 02:31:05 -08001/*
2 * LED Triggers Core
3 *
Richard Purdief8a7c6f2007-07-08 23:19:31 +01004 * Copyright 2005-2007 Openedhand Ltd.
Richard Purdiec3bc9952006-03-31 02:31:05 -08005 *
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
Richard Purdiec3bc9952006-03-31 02:31:05 -080014#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>
Richard Purdiec3bc9952006-03-31 02:31:05 -080020#include <linux/timer.h>
Richard Purdiedc472062007-11-10 13:29:04 +000021#include <linux/rwsem.h>
Richard Purdiec3bc9952006-03-31 02:31:05 -080022#include <linux/leds.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090023#include <linux/slab.h>
Richard Purdiec3bc9952006-03-31 02:31:05 -080024#include "leds.h"
25
26/*
27 * Nests outside led_cdev->trigger_lock
28 */
Richard Purdiedc472062007-11-10 13:29:04 +000029static DECLARE_RWSEM(triggers_list_lock);
Richard Purdiec3bc9952006-03-31 02:31:05 -080030static LIST_HEAD(trigger_list);
31
Németh Márton4d404fd2008-03-09 20:59:57 +000032 /* Used by LED Class */
33
Richard Purdief8a7c6f2007-07-08 23:19:31 +010034ssize_t led_trigger_store(struct device *dev, struct device_attribute *attr,
35 const char *buf, size_t count)
Richard Purdiec3bc9952006-03-31 02:31:05 -080036{
Richard Purdief8a7c6f2007-07-08 23:19:31 +010037 struct led_classdev *led_cdev = dev_get_drvdata(dev);
Richard Purdiec3bc9952006-03-31 02:31:05 -080038 char trigger_name[TRIG_NAME_MAX];
39 struct led_trigger *trig;
40 size_t len;
41
42 trigger_name[sizeof(trigger_name) - 1] = '\0';
43 strncpy(trigger_name, buf, sizeof(trigger_name) - 1);
44 len = strlen(trigger_name);
45
46 if (len && trigger_name[len - 1] == '\n')
47 trigger_name[len - 1] = '\0';
48
49 if (!strcmp(trigger_name, "none")) {
Németh Márton0013b232008-03-09 20:54:37 +000050 led_trigger_remove(led_cdev);
Richard Purdiec3bc9952006-03-31 02:31:05 -080051 return count;
52 }
53
Richard Purdiedc472062007-11-10 13:29:04 +000054 down_read(&triggers_list_lock);
Richard Purdiec3bc9952006-03-31 02:31:05 -080055 list_for_each_entry(trig, &trigger_list, next_trig) {
56 if (!strcmp(trigger_name, trig->name)) {
Richard Purdiedc472062007-11-10 13:29:04 +000057 down_write(&led_cdev->trigger_lock);
Richard Purdiec3bc9952006-03-31 02:31:05 -080058 led_trigger_set(led_cdev, trig);
Richard Purdiedc472062007-11-10 13:29:04 +000059 up_write(&led_cdev->trigger_lock);
Richard Purdiec3bc9952006-03-31 02:31:05 -080060
Richard Purdiedc472062007-11-10 13:29:04 +000061 up_read(&triggers_list_lock);
Richard Purdiec3bc9952006-03-31 02:31:05 -080062 return count;
63 }
64 }
Richard Purdiedc472062007-11-10 13:29:04 +000065 up_read(&triggers_list_lock);
Richard Purdiec3bc9952006-03-31 02:31:05 -080066
67 return -EINVAL;
68}
Németh Márton4d404fd2008-03-09 20:59:57 +000069EXPORT_SYMBOL_GPL(led_trigger_store);
Richard Purdiec3bc9952006-03-31 02:31:05 -080070
Richard Purdief8a7c6f2007-07-08 23:19:31 +010071ssize_t led_trigger_show(struct device *dev, struct device_attribute *attr,
72 char *buf)
Richard Purdiec3bc9952006-03-31 02:31:05 -080073{
Richard Purdief8a7c6f2007-07-08 23:19:31 +010074 struct led_classdev *led_cdev = dev_get_drvdata(dev);
Richard Purdiec3bc9952006-03-31 02:31:05 -080075 struct led_trigger *trig;
76 int len = 0;
77
Richard Purdiedc472062007-11-10 13:29:04 +000078 down_read(&triggers_list_lock);
79 down_read(&led_cdev->trigger_lock);
Richard Purdiec3bc9952006-03-31 02:31:05 -080080
81 if (!led_cdev->trigger)
82 len += sprintf(buf+len, "[none] ");
83 else
84 len += sprintf(buf+len, "none ");
85
86 list_for_each_entry(trig, &trigger_list, next_trig) {
87 if (led_cdev->trigger && !strcmp(led_cdev->trigger->name,
88 trig->name))
89 len += sprintf(buf+len, "[%s] ", trig->name);
90 else
91 len += sprintf(buf+len, "%s ", trig->name);
92 }
Richard Purdiedc472062007-11-10 13:29:04 +000093 up_read(&led_cdev->trigger_lock);
94 up_read(&triggers_list_lock);
Richard Purdiec3bc9952006-03-31 02:31:05 -080095
96 len += sprintf(len+buf, "\n");
97 return len;
98}
Németh Márton4d404fd2008-03-09 20:59:57 +000099EXPORT_SYMBOL_GPL(led_trigger_show);
Richard Purdiec3bc9952006-03-31 02:31:05 -0800100
101/* Caller must ensure led_cdev->trigger_lock held */
Bryan Wueb202622012-04-19 11:46:33 +0800102void led_trigger_set(struct led_classdev *led_cdev, struct led_trigger *trig)
Richard Purdiec3bc9952006-03-31 02:31:05 -0800103{
104 unsigned long flags;
Colin Cross52c47742012-08-27 09:31:49 +0800105 char *event = NULL;
106 char *envp[2];
107 const char *name;
108
109 name = trig ? trig->name : "none";
110 event = kasprintf(GFP_KERNEL, "TRIGGER=%s", name);
Richard Purdiec3bc9952006-03-31 02:31:05 -0800111
112 /* Remove any existing trigger */
113 if (led_cdev->trigger) {
114 write_lock_irqsave(&led_cdev->trigger->leddev_list_lock, flags);
115 list_del(&led_cdev->trig_list);
Németh Márton4d404fd2008-03-09 20:59:57 +0000116 write_unlock_irqrestore(&led_cdev->trigger->leddev_list_lock,
117 flags);
Fabio Baltierid23a22a2012-08-15 21:44:34 +0800118 cancel_work_sync(&led_cdev->set_brightness_work);
119 led_stop_software_blink(led_cdev);
Richard Purdiec3bc9952006-03-31 02:31:05 -0800120 if (led_cdev->trigger->deactivate)
121 led_cdev->trigger->deactivate(led_cdev);
Dmitry Baryshkovfe3025b2008-07-16 22:51:14 +0100122 led_cdev->trigger = NULL;
Shuah Khan19cd67e2012-06-14 04:34:30 +0800123 led_set_brightness(led_cdev, LED_OFF);
Richard Purdiec3bc9952006-03-31 02:31:05 -0800124 }
Bryan Wueb202622012-04-19 11:46:33 +0800125 if (trig) {
126 write_lock_irqsave(&trig->leddev_list_lock, flags);
127 list_add_tail(&led_cdev->trig_list, &trig->led_cdevs);
128 write_unlock_irqrestore(&trig->leddev_list_lock, flags);
129 led_cdev->trigger = trig;
130 if (trig->activate)
131 trig->activate(led_cdev);
Richard Purdiec3bc9952006-03-31 02:31:05 -0800132 }
Colin Cross52c47742012-08-27 09:31:49 +0800133
134 if (event) {
135 envp[0] = event;
136 envp[1] = NULL;
137 kobject_uevent_env(&led_cdev->dev->kobj, KOBJ_CHANGE, envp);
138 kfree(event);
139 }
Richard Purdiec3bc9952006-03-31 02:31:05 -0800140}
Németh Márton4d404fd2008-03-09 20:59:57 +0000141EXPORT_SYMBOL_GPL(led_trigger_set);
Richard Purdiec3bc9952006-03-31 02:31:05 -0800142
Németh Márton0013b232008-03-09 20:54:37 +0000143void led_trigger_remove(struct led_classdev *led_cdev)
144{
145 down_write(&led_cdev->trigger_lock);
146 led_trigger_set(led_cdev, NULL);
147 up_write(&led_cdev->trigger_lock);
148}
Németh Márton4d404fd2008-03-09 20:59:57 +0000149EXPORT_SYMBOL_GPL(led_trigger_remove);
Németh Márton0013b232008-03-09 20:54:37 +0000150
Richard Purdiec3bc9952006-03-31 02:31:05 -0800151void led_trigger_set_default(struct led_classdev *led_cdev)
152{
153 struct led_trigger *trig;
154
155 if (!led_cdev->default_trigger)
156 return;
157
Richard Purdiedc472062007-11-10 13:29:04 +0000158 down_read(&triggers_list_lock);
159 down_write(&led_cdev->trigger_lock);
Richard Purdiec3bc9952006-03-31 02:31:05 -0800160 list_for_each_entry(trig, &trigger_list, next_trig) {
161 if (!strcmp(led_cdev->default_trigger, trig->name))
162 led_trigger_set(led_cdev, trig);
163 }
Richard Purdiedc472062007-11-10 13:29:04 +0000164 up_write(&led_cdev->trigger_lock);
165 up_read(&triggers_list_lock);
Richard Purdiec3bc9952006-03-31 02:31:05 -0800166}
Németh Márton4d404fd2008-03-09 20:59:57 +0000167EXPORT_SYMBOL_GPL(led_trigger_set_default);
168
Fabio Baltieria8df7b12012-11-04 01:54:34 -0800169void led_trigger_rename_static(const char *name, struct led_trigger *trig)
170{
171 /* new name must be on a temporary string to prevent races */
172 BUG_ON(name == trig->name);
173
174 down_write(&triggers_list_lock);
175 /* this assumes that trig->name was originaly allocated to
176 * non constant storage */
177 strcpy((char *)trig->name, name);
178 up_write(&triggers_list_lock);
179}
180EXPORT_SYMBOL_GPL(led_trigger_rename_static);
181
Németh Márton4d404fd2008-03-09 20:59:57 +0000182/* LED Trigger Interface */
Richard Purdiec3bc9952006-03-31 02:31:05 -0800183
Bryan Wueb202622012-04-19 11:46:33 +0800184int led_trigger_register(struct led_trigger *trig)
Richard Purdiec3bc9952006-03-31 02:31:05 -0800185{
186 struct led_classdev *led_cdev;
Bryan Wueb202622012-04-19 11:46:33 +0800187 struct led_trigger *_trig;
Richard Purdiec3bc9952006-03-31 02:31:05 -0800188
Bryan Wueb202622012-04-19 11:46:33 +0800189 rwlock_init(&trig->leddev_list_lock);
190 INIT_LIST_HEAD(&trig->led_cdevs);
Richard Purdiec3bc9952006-03-31 02:31:05 -0800191
Richard Purdiedc472062007-11-10 13:29:04 +0000192 down_write(&triggers_list_lock);
Adam Nielsen700c6ea2009-02-18 08:18:04 +1000193 /* Make sure the trigger's name isn't already in use */
Bryan Wueb202622012-04-19 11:46:33 +0800194 list_for_each_entry(_trig, &trigger_list, next_trig) {
195 if (!strcmp(_trig->name, trig->name)) {
Adam Nielsen700c6ea2009-02-18 08:18:04 +1000196 up_write(&triggers_list_lock);
197 return -EEXIST;
198 }
199 }
200 /* Add to the list of led triggers */
Bryan Wueb202622012-04-19 11:46:33 +0800201 list_add_tail(&trig->next_trig, &trigger_list);
Richard Purdiedc472062007-11-10 13:29:04 +0000202 up_write(&triggers_list_lock);
Richard Purdiec3bc9952006-03-31 02:31:05 -0800203
204 /* Register with any LEDs that have this as a default trigger */
Richard Purdie72f8da32007-12-31 23:09:44 +0000205 down_read(&leds_list_lock);
Richard Purdiec3bc9952006-03-31 02:31:05 -0800206 list_for_each_entry(led_cdev, &leds_list, node) {
Richard Purdiedc472062007-11-10 13:29:04 +0000207 down_write(&led_cdev->trigger_lock);
Richard Purdiec3bc9952006-03-31 02:31:05 -0800208 if (!led_cdev->trigger && led_cdev->default_trigger &&
Bryan Wueb202622012-04-19 11:46:33 +0800209 !strcmp(led_cdev->default_trigger, trig->name))
210 led_trigger_set(led_cdev, trig);
Richard Purdiedc472062007-11-10 13:29:04 +0000211 up_write(&led_cdev->trigger_lock);
Richard Purdiec3bc9952006-03-31 02:31:05 -0800212 }
Richard Purdie72f8da32007-12-31 23:09:44 +0000213 up_read(&leds_list_lock);
Richard Purdiec3bc9952006-03-31 02:31:05 -0800214
215 return 0;
216}
Németh Márton4d404fd2008-03-09 20:59:57 +0000217EXPORT_SYMBOL_GPL(led_trigger_register);
Richard Purdiec3bc9952006-03-31 02:31:05 -0800218
Bryan Wueb202622012-04-19 11:46:33 +0800219void led_trigger_unregister(struct led_trigger *trig)
Richard Purdiec3bc9952006-03-31 02:31:05 -0800220{
221 struct led_classdev *led_cdev;
222
223 /* Remove from the list of led triggers */
Richard Purdiedc472062007-11-10 13:29:04 +0000224 down_write(&triggers_list_lock);
Bryan Wueb202622012-04-19 11:46:33 +0800225 list_del(&trig->next_trig);
Richard Purdiedc472062007-11-10 13:29:04 +0000226 up_write(&triggers_list_lock);
Richard Purdiec3bc9952006-03-31 02:31:05 -0800227
228 /* Remove anyone actively using this trigger */
Richard Purdie72f8da32007-12-31 23:09:44 +0000229 down_read(&leds_list_lock);
Richard Purdiec3bc9952006-03-31 02:31:05 -0800230 list_for_each_entry(led_cdev, &leds_list, node) {
Richard Purdiedc472062007-11-10 13:29:04 +0000231 down_write(&led_cdev->trigger_lock);
Bryan Wueb202622012-04-19 11:46:33 +0800232 if (led_cdev->trigger == trig)
Richard Purdiec3bc9952006-03-31 02:31:05 -0800233 led_trigger_set(led_cdev, NULL);
Richard Purdiedc472062007-11-10 13:29:04 +0000234 up_write(&led_cdev->trigger_lock);
Richard Purdiec3bc9952006-03-31 02:31:05 -0800235 }
Richard Purdie72f8da32007-12-31 23:09:44 +0000236 up_read(&leds_list_lock);
Richard Purdiec3bc9952006-03-31 02:31:05 -0800237}
Németh Márton4d404fd2008-03-09 20:59:57 +0000238EXPORT_SYMBOL_GPL(led_trigger_unregister);
239
240/* Simple LED Tigger Interface */
241
Bryan Wueb202622012-04-19 11:46:33 +0800242void led_trigger_event(struct led_trigger *trig,
Németh Márton4d404fd2008-03-09 20:59:57 +0000243 enum led_brightness brightness)
244{
ZHAO Gang11e043b2013-12-28 07:00:26 -0800245 struct led_classdev *led_cdev;
Németh Márton4d404fd2008-03-09 20:59:57 +0000246
Bryan Wueb202622012-04-19 11:46:33 +0800247 if (!trig)
Németh Márton4d404fd2008-03-09 20:59:57 +0000248 return;
249
Bryan Wueb202622012-04-19 11:46:33 +0800250 read_lock(&trig->leddev_list_lock);
ZHAO Gang11e043b2013-12-28 07:00:26 -0800251 list_for_each_entry(led_cdev, &trig->led_cdevs, trig_list)
Fabio Baltierid23a22a2012-08-15 21:44:34 +0800252 led_set_brightness(led_cdev, brightness);
Bryan Wueb202622012-04-19 11:46:33 +0800253 read_unlock(&trig->leddev_list_lock);
Németh Márton4d404fd2008-03-09 20:59:57 +0000254}
255EXPORT_SYMBOL_GPL(led_trigger_event);
256
Bryan Wu20c0e6b2012-06-15 22:15:27 +0800257static void led_trigger_blink_setup(struct led_trigger *trig,
Fabio Baltieri5bb629c2012-05-27 07:19:22 +0800258 unsigned long *delay_on,
259 unsigned long *delay_off,
260 int oneshot,
261 int invert)
Vasily Khoruzhick0b9536c2011-01-07 16:28:16 +0000262{
ZHAO Gang11e043b2013-12-28 07:00:26 -0800263 struct led_classdev *led_cdev;
Vasily Khoruzhick0b9536c2011-01-07 16:28:16 +0000264
Bryan Wueb202622012-04-19 11:46:33 +0800265 if (!trig)
Vasily Khoruzhick0b9536c2011-01-07 16:28:16 +0000266 return;
267
Bryan Wueb202622012-04-19 11:46:33 +0800268 read_lock(&trig->leddev_list_lock);
ZHAO Gang11e043b2013-12-28 07:00:26 -0800269 list_for_each_entry(led_cdev, &trig->led_cdevs, trig_list) {
Fabio Baltieri5bb629c2012-05-27 07:19:22 +0800270 if (oneshot)
271 led_blink_set_oneshot(led_cdev, delay_on, delay_off,
272 invert);
273 else
274 led_blink_set(led_cdev, delay_on, delay_off);
Vasily Khoruzhick0b9536c2011-01-07 16:28:16 +0000275 }
Bryan Wueb202622012-04-19 11:46:33 +0800276 read_unlock(&trig->leddev_list_lock);
Vasily Khoruzhick0b9536c2011-01-07 16:28:16 +0000277}
Fabio Baltieri5bb629c2012-05-27 07:19:22 +0800278
279void led_trigger_blink(struct led_trigger *trig,
280 unsigned long *delay_on,
281 unsigned long *delay_off)
282{
283 led_trigger_blink_setup(trig, delay_on, delay_off, 0, 0);
284}
Vasily Khoruzhick0b9536c2011-01-07 16:28:16 +0000285EXPORT_SYMBOL_GPL(led_trigger_blink);
286
Fabio Baltieri5bb629c2012-05-27 07:19:22 +0800287void led_trigger_blink_oneshot(struct led_trigger *trig,
288 unsigned long *delay_on,
289 unsigned long *delay_off,
290 int invert)
291{
292 led_trigger_blink_setup(trig, delay_on, delay_off, 1, invert);
293}
294EXPORT_SYMBOL_GPL(led_trigger_blink_oneshot);
295
Németh Márton4d404fd2008-03-09 20:59:57 +0000296void led_trigger_register_simple(const char *name, struct led_trigger **tp)
297{
Bryan Wueb202622012-04-19 11:46:33 +0800298 struct led_trigger *trig;
Németh Márton4d404fd2008-03-09 20:59:57 +0000299 int err;
300
Bryan Wueb202622012-04-19 11:46:33 +0800301 trig = kzalloc(sizeof(struct led_trigger), GFP_KERNEL);
Németh Márton4d404fd2008-03-09 20:59:57 +0000302
Bryan Wueb202622012-04-19 11:46:33 +0800303 if (trig) {
304 trig->name = name;
305 err = led_trigger_register(trig);
Masakazu Mokunocba4c2a2011-10-31 17:11:59 -0700306 if (err < 0) {
Bryan Wueb202622012-04-19 11:46:33 +0800307 kfree(trig);
308 trig = NULL;
Sachin Kamat09f5fe72012-11-25 13:00:44 +0530309 pr_warn("LED trigger %s failed to register (%d)\n",
310 name, err);
Masakazu Mokunocba4c2a2011-10-31 17:11:59 -0700311 }
Sachin Kamat09f5fe72012-11-25 13:00:44 +0530312 } else {
313 pr_warn("LED trigger %s failed to register (no memory)\n",
314 name);
315 }
Bryan Wueb202622012-04-19 11:46:33 +0800316 *tp = trig;
Németh Márton4d404fd2008-03-09 20:59:57 +0000317}
318EXPORT_SYMBOL_GPL(led_trigger_register_simple);
Richard Purdiec3bc9952006-03-31 02:31:05 -0800319
Bryan Wueb202622012-04-19 11:46:33 +0800320void led_trigger_unregister_simple(struct led_trigger *trig)
Richard Purdiec3bc9952006-03-31 02:31:05 -0800321{
Bryan Wueb202622012-04-19 11:46:33 +0800322 if (trig)
323 led_trigger_unregister(trig);
324 kfree(trig);
Richard Purdiec3bc9952006-03-31 02:31:05 -0800325}
Richard Purdiec3bc9952006-03-31 02:31:05 -0800326EXPORT_SYMBOL_GPL(led_trigger_unregister_simple);
Richard Purdiec3bc9952006-03-31 02:31:05 -0800327
328MODULE_AUTHOR("Richard Purdie");
329MODULE_LICENSE("GPL");
330MODULE_DESCRIPTION("LED Triggers Core");