Commit | Line | Data |
---|---|---|
d2912cb1 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
c3bc9956 RP |
2 | /* |
3 | * LED Triggers Core | |
4 | * | |
f8a7c6fe | 5 | * Copyright 2005-2007 Openedhand Ltd. |
c3bc9956 RP |
6 | * |
7 | * Author: Richard Purdie <rpurdie@openedhand.com> | |
c3bc9956 RP |
8 | */ |
9 | ||
50237863 | 10 | #include <linux/export.h> |
c3bc9956 | 11 | #include <linux/kernel.h> |
c3bc9956 RP |
12 | #include <linux/list.h> |
13 | #include <linux/spinlock.h> | |
14 | #include <linux/device.h> | |
c3bc9956 | 15 | #include <linux/timer.h> |
dc47206e | 16 | #include <linux/rwsem.h> |
c3bc9956 | 17 | #include <linux/leds.h> |
5a0e3ad6 | 18 | #include <linux/slab.h> |
c3bc9956 RP |
19 | #include "leds.h" |
20 | ||
21 | /* | |
22 | * Nests outside led_cdev->trigger_lock | |
23 | */ | |
dc47206e | 24 | static DECLARE_RWSEM(triggers_list_lock); |
ba93cdce | 25 | LIST_HEAD(trigger_list); |
c3bc9956 | 26 | |
4d404fd5 NM |
27 | /* Used by LED Class */ |
28 | ||
f8a7c6fe RP |
29 | ssize_t led_trigger_store(struct device *dev, struct device_attribute *attr, |
30 | const char *buf, size_t count) | |
c3bc9956 | 31 | { |
f8a7c6fe | 32 | struct led_classdev *led_cdev = dev_get_drvdata(dev); |
c3bc9956 | 33 | struct led_trigger *trig; |
acd899e4 JA |
34 | int ret = count; |
35 | ||
36 | mutex_lock(&led_cdev->led_access); | |
37 | ||
38 | if (led_sysfs_is_disabled(led_cdev)) { | |
39 | ret = -EBUSY; | |
40 | goto unlock; | |
41 | } | |
c3bc9956 | 42 | |
7296c33e | 43 | if (sysfs_streq(buf, "none")) { |
0013b23d | 44 | led_trigger_remove(led_cdev); |
acd899e4 | 45 | goto unlock; |
c3bc9956 RP |
46 | } |
47 | ||
dc47206e | 48 | down_read(&triggers_list_lock); |
c3bc9956 | 49 | list_for_each_entry(trig, &trigger_list, next_trig) { |
7296c33e | 50 | if (sysfs_streq(buf, trig->name)) { |
dc47206e | 51 | down_write(&led_cdev->trigger_lock); |
c3bc9956 | 52 | led_trigger_set(led_cdev, trig); |
dc47206e | 53 | up_write(&led_cdev->trigger_lock); |
c3bc9956 | 54 | |
dc47206e | 55 | up_read(&triggers_list_lock); |
acd899e4 | 56 | goto unlock; |
c3bc9956 RP |
57 | } |
58 | } | |
a3eac76c HK |
59 | /* we come here only if buf matches no trigger */ |
60 | ret = -EINVAL; | |
dc47206e | 61 | up_read(&triggers_list_lock); |
c3bc9956 | 62 | |
acd899e4 JA |
63 | unlock: |
64 | mutex_unlock(&led_cdev->led_access); | |
65 | return ret; | |
c3bc9956 | 66 | } |
4d404fd5 | 67 | EXPORT_SYMBOL_GPL(led_trigger_store); |
c3bc9956 | 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) | |
3b9b9536 | 80 | len += scnprintf(buf+len, PAGE_SIZE - len, "[none] "); |
c3bc9956 | 81 | else |
3b9b9536 | 82 | len += scnprintf(buf+len, PAGE_SIZE - len, "none "); |
c3bc9956 RP |
83 | |
84 | list_for_each_entry(trig, &trigger_list, next_trig) { | |
85 | if (led_cdev->trigger && !strcmp(led_cdev->trigger->name, | |
86 | trig->name)) | |
3b9b9536 NS |
87 | len += scnprintf(buf+len, PAGE_SIZE - len, "[%s] ", |
88 | trig->name); | |
c3bc9956 | 89 | else |
3b9b9536 NS |
90 | len += scnprintf(buf+len, PAGE_SIZE - len, "%s ", |
91 | trig->name); | |
c3bc9956 | 92 | } |
dc47206e RP |
93 | up_read(&led_cdev->trigger_lock); |
94 | up_read(&triggers_list_lock); | |
c3bc9956 | 95 | |
3b9b9536 | 96 | len += scnprintf(len+buf, PAGE_SIZE - len, "\n"); |
c3bc9956 RP |
97 | return len; |
98 | } | |
4d404fd5 | 99 | EXPORT_SYMBOL_GPL(led_trigger_show); |
c3bc9956 RP |
100 | |
101 | /* Caller must ensure led_cdev->trigger_lock held */ | |
2282e125 | 102 | int led_trigger_set(struct led_classdev *led_cdev, struct led_trigger *trig) |
c3bc9956 RP |
103 | { |
104 | unsigned long flags; | |
52c47742 CC |
105 | char *event = NULL; |
106 | char *envp[2]; | |
107 | const char *name; | |
2282e125 | 108 | int ret; |
52c47742 | 109 | |
fbfa197a | 110 | if (!led_cdev->trigger && !trig) |
2282e125 | 111 | return 0; |
fbfa197a | 112 | |
52c47742 CC |
113 | name = trig ? trig->name : "none"; |
114 | event = kasprintf(GFP_KERNEL, "TRIGGER=%s", name); | |
c3bc9956 RP |
115 | |
116 | /* Remove any existing trigger */ | |
117 | if (led_cdev->trigger) { | |
118 | write_lock_irqsave(&led_cdev->trigger->leddev_list_lock, flags); | |
119 | list_del(&led_cdev->trig_list); | |
4d404fd5 NM |
120 | write_unlock_irqrestore(&led_cdev->trigger->leddev_list_lock, |
121 | flags); | |
d23a22a7 FB |
122 | cancel_work_sync(&led_cdev->set_brightness_work); |
123 | led_stop_software_blink(led_cdev); | |
c3bc9956 RP |
124 | if (led_cdev->trigger->deactivate) |
125 | led_cdev->trigger->deactivate(led_cdev); | |
a7e7a315 | 126 | device_remove_groups(led_cdev->dev, led_cdev->trigger->groups); |
fe3025b5 | 127 | led_cdev->trigger = NULL; |
a7d5904a UKK |
128 | led_cdev->trigger_data = NULL; |
129 | led_cdev->activated = false; | |
19cd67e2 | 130 | led_set_brightness(led_cdev, LED_OFF); |
c3bc9956 | 131 | } |
eb202621 BW |
132 | if (trig) { |
133 | write_lock_irqsave(&trig->leddev_list_lock, flags); | |
134 | list_add_tail(&led_cdev->trig_list, &trig->led_cdevs); | |
135 | write_unlock_irqrestore(&trig->leddev_list_lock, flags); | |
136 | led_cdev->trigger = trig; | |
2282e125 | 137 | |
eb202621 | 138 | if (trig->activate) |
2282e125 UKK |
139 | ret = trig->activate(led_cdev); |
140 | else | |
141 | ret = 0; | |
142 | ||
143 | if (ret) | |
144 | goto err_activate; | |
a7e7a315 UKK |
145 | |
146 | ret = device_add_groups(led_cdev->dev, trig->groups); | |
147 | if (ret) { | |
148 | dev_err(led_cdev->dev, "Failed to add trigger attributes\n"); | |
149 | goto err_add_groups; | |
150 | } | |
c3bc9956 | 151 | } |
52c47742 CC |
152 | |
153 | if (event) { | |
154 | envp[0] = event; | |
155 | envp[1] = NULL; | |
6f3bad96 JA |
156 | if (kobject_uevent_env(&led_cdev->dev->kobj, KOBJ_CHANGE, envp)) |
157 | dev_err(led_cdev->dev, | |
158 | "%s: Error sending uevent\n", __func__); | |
52c47742 CC |
159 | kfree(event); |
160 | } | |
2282e125 UKK |
161 | |
162 | return 0; | |
163 | ||
a7e7a315 UKK |
164 | err_add_groups: |
165 | ||
166 | if (trig->deactivate) | |
167 | trig->deactivate(led_cdev); | |
2282e125 | 168 | err_activate: |
a7e7a315 | 169 | |
2282e125 | 170 | led_cdev->trigger = NULL; |
a7d5904a | 171 | led_cdev->trigger_data = NULL; |
2282e125 UKK |
172 | write_lock_irqsave(&led_cdev->trigger->leddev_list_lock, flags); |
173 | list_del(&led_cdev->trig_list); | |
174 | write_unlock_irqrestore(&led_cdev->trigger->leddev_list_lock, flags); | |
175 | led_set_brightness(led_cdev, LED_OFF); | |
176 | ||
177 | return ret; | |
c3bc9956 | 178 | } |
4d404fd5 | 179 | EXPORT_SYMBOL_GPL(led_trigger_set); |
c3bc9956 | 180 | |
0013b23d NM |
181 | void led_trigger_remove(struct led_classdev *led_cdev) |
182 | { | |
183 | down_write(&led_cdev->trigger_lock); | |
184 | led_trigger_set(led_cdev, NULL); | |
185 | up_write(&led_cdev->trigger_lock); | |
186 | } | |
4d404fd5 | 187 | EXPORT_SYMBOL_GPL(led_trigger_remove); |
0013b23d | 188 | |
c3bc9956 RP |
189 | void led_trigger_set_default(struct led_classdev *led_cdev) |
190 | { | |
191 | struct led_trigger *trig; | |
192 | ||
193 | if (!led_cdev->default_trigger) | |
194 | return; | |
195 | ||
dc47206e RP |
196 | down_read(&triggers_list_lock); |
197 | down_write(&led_cdev->trigger_lock); | |
c3bc9956 | 198 | list_for_each_entry(trig, &trigger_list, next_trig) { |
c4f7bd4a | 199 | if (!strcmp(led_cdev->default_trigger, trig->name)) { |
02d31765 | 200 | led_cdev->flags |= LED_INIT_DEFAULT_TRIGGER; |
c3bc9956 | 201 | led_trigger_set(led_cdev, trig); |
c4f7bd4a JA |
202 | break; |
203 | } | |
c3bc9956 | 204 | } |
dc47206e RP |
205 | up_write(&led_cdev->trigger_lock); |
206 | up_read(&triggers_list_lock); | |
c3bc9956 | 207 | } |
4d404fd5 NM |
208 | EXPORT_SYMBOL_GPL(led_trigger_set_default); |
209 | ||
a8df7b1a FB |
210 | void led_trigger_rename_static(const char *name, struct led_trigger *trig) |
211 | { | |
212 | /* new name must be on a temporary string to prevent races */ | |
213 | BUG_ON(name == trig->name); | |
214 | ||
215 | down_write(&triggers_list_lock); | |
216 | /* this assumes that trig->name was originaly allocated to | |
217 | * non constant storage */ | |
218 | strcpy((char *)trig->name, name); | |
219 | up_write(&triggers_list_lock); | |
220 | } | |
221 | EXPORT_SYMBOL_GPL(led_trigger_rename_static); | |
222 | ||
4d404fd5 | 223 | /* LED Trigger Interface */ |
c3bc9956 | 224 | |
eb202621 | 225 | int led_trigger_register(struct led_trigger *trig) |
c3bc9956 RP |
226 | { |
227 | struct led_classdev *led_cdev; | |
eb202621 | 228 | struct led_trigger *_trig; |
c3bc9956 | 229 | |
eb202621 BW |
230 | rwlock_init(&trig->leddev_list_lock); |
231 | INIT_LIST_HEAD(&trig->led_cdevs); | |
c3bc9956 | 232 | |
dc47206e | 233 | down_write(&triggers_list_lock); |
700c6ea2 | 234 | /* Make sure the trigger's name isn't already in use */ |
eb202621 BW |
235 | list_for_each_entry(_trig, &trigger_list, next_trig) { |
236 | if (!strcmp(_trig->name, trig->name)) { | |
700c6ea2 AN |
237 | up_write(&triggers_list_lock); |
238 | return -EEXIST; | |
239 | } | |
240 | } | |
241 | /* Add to the list of led triggers */ | |
eb202621 | 242 | list_add_tail(&trig->next_trig, &trigger_list); |
dc47206e | 243 | up_write(&triggers_list_lock); |
c3bc9956 RP |
244 | |
245 | /* Register with any LEDs that have this as a default trigger */ | |
72f8da32 | 246 | down_read(&leds_list_lock); |
c3bc9956 | 247 | list_for_each_entry(led_cdev, &leds_list, node) { |
dc47206e | 248 | down_write(&led_cdev->trigger_lock); |
c3bc9956 | 249 | if (!led_cdev->trigger && led_cdev->default_trigger && |
8146aace KK |
250 | !strcmp(led_cdev->default_trigger, trig->name)) { |
251 | led_cdev->flags |= LED_INIT_DEFAULT_TRIGGER; | |
eb202621 | 252 | led_trigger_set(led_cdev, trig); |
8146aace | 253 | } |
dc47206e | 254 | up_write(&led_cdev->trigger_lock); |
c3bc9956 | 255 | } |
72f8da32 | 256 | up_read(&leds_list_lock); |
c3bc9956 RP |
257 | |
258 | return 0; | |
259 | } | |
4d404fd5 | 260 | EXPORT_SYMBOL_GPL(led_trigger_register); |
c3bc9956 | 261 | |
eb202621 | 262 | void led_trigger_unregister(struct led_trigger *trig) |
c3bc9956 RP |
263 | { |
264 | struct led_classdev *led_cdev; | |
265 | ||
14f5716b SL |
266 | if (list_empty_careful(&trig->next_trig)) |
267 | return; | |
268 | ||
c3bc9956 | 269 | /* Remove from the list of led triggers */ |
dc47206e | 270 | down_write(&triggers_list_lock); |
14f5716b | 271 | list_del_init(&trig->next_trig); |
dc47206e | 272 | up_write(&triggers_list_lock); |
c3bc9956 RP |
273 | |
274 | /* Remove anyone actively using this trigger */ | |
72f8da32 | 275 | down_read(&leds_list_lock); |
c3bc9956 | 276 | list_for_each_entry(led_cdev, &leds_list, node) { |
dc47206e | 277 | down_write(&led_cdev->trigger_lock); |
eb202621 | 278 | if (led_cdev->trigger == trig) |
c3bc9956 | 279 | led_trigger_set(led_cdev, NULL); |
dc47206e | 280 | up_write(&led_cdev->trigger_lock); |
c3bc9956 | 281 | } |
72f8da32 | 282 | up_read(&leds_list_lock); |
c3bc9956 | 283 | } |
4d404fd5 | 284 | EXPORT_SYMBOL_GPL(led_trigger_unregister); |
c3bc9956 | 285 | |
9534cc31 HK |
286 | static void devm_led_trigger_release(struct device *dev, void *res) |
287 | { | |
288 | led_trigger_unregister(*(struct led_trigger **)res); | |
289 | } | |
290 | ||
291 | int devm_led_trigger_register(struct device *dev, | |
292 | struct led_trigger *trig) | |
293 | { | |
294 | struct led_trigger **dr; | |
295 | int rc; | |
296 | ||
297 | dr = devres_alloc(devm_led_trigger_release, sizeof(*dr), | |
298 | GFP_KERNEL); | |
299 | if (!dr) | |
300 | return -ENOMEM; | |
301 | ||
302 | *dr = trig; | |
303 | ||
304 | rc = led_trigger_register(trig); | |
305 | if (rc) | |
306 | devres_free(dr); | |
307 | else | |
308 | devres_add(dev, dr); | |
309 | ||
310 | return rc; | |
311 | } | |
312 | EXPORT_SYMBOL_GPL(devm_led_trigger_register); | |
313 | ||
4d404fd5 NM |
314 | /* Simple LED Tigger Interface */ |
315 | ||
eb202621 | 316 | void led_trigger_event(struct led_trigger *trig, |
4d404fd5 | 317 | enum led_brightness brightness) |
c3bc9956 | 318 | { |
11e043b5 | 319 | struct led_classdev *led_cdev; |
4d404fd5 | 320 | |
eb202621 | 321 | if (!trig) |
4d404fd5 NM |
322 | return; |
323 | ||
eb202621 | 324 | read_lock(&trig->leddev_list_lock); |
11e043b5 | 325 | list_for_each_entry(led_cdev, &trig->led_cdevs, trig_list) |
d23a22a7 | 326 | led_set_brightness(led_cdev, brightness); |
eb202621 | 327 | read_unlock(&trig->leddev_list_lock); |
c3bc9956 | 328 | } |
4d404fd5 | 329 | EXPORT_SYMBOL_GPL(led_trigger_event); |
c3bc9956 | 330 | |
20c0e6b8 | 331 | static void led_trigger_blink_setup(struct led_trigger *trig, |
5bb629c5 FB |
332 | unsigned long *delay_on, |
333 | unsigned long *delay_off, | |
334 | int oneshot, | |
335 | int invert) | |
0b9536c9 | 336 | { |
11e043b5 | 337 | struct led_classdev *led_cdev; |
0b9536c9 | 338 | |
eb202621 | 339 | if (!trig) |
0b9536c9 VK |
340 | return; |
341 | ||
eb202621 | 342 | read_lock(&trig->leddev_list_lock); |
11e043b5 | 343 | list_for_each_entry(led_cdev, &trig->led_cdevs, trig_list) { |
5bb629c5 FB |
344 | if (oneshot) |
345 | led_blink_set_oneshot(led_cdev, delay_on, delay_off, | |
346 | invert); | |
347 | else | |
348 | led_blink_set(led_cdev, delay_on, delay_off); | |
0b9536c9 | 349 | } |
eb202621 | 350 | read_unlock(&trig->leddev_list_lock); |
0b9536c9 | 351 | } |
5bb629c5 FB |
352 | |
353 | void led_trigger_blink(struct led_trigger *trig, | |
354 | unsigned long *delay_on, | |
355 | unsigned long *delay_off) | |
356 | { | |
357 | led_trigger_blink_setup(trig, delay_on, delay_off, 0, 0); | |
358 | } | |
0b9536c9 VK |
359 | EXPORT_SYMBOL_GPL(led_trigger_blink); |
360 | ||
5bb629c5 FB |
361 | void led_trigger_blink_oneshot(struct led_trigger *trig, |
362 | unsigned long *delay_on, | |
363 | unsigned long *delay_off, | |
364 | int invert) | |
365 | { | |
366 | led_trigger_blink_setup(trig, delay_on, delay_off, 1, invert); | |
367 | } | |
368 | EXPORT_SYMBOL_GPL(led_trigger_blink_oneshot); | |
369 | ||
4d404fd5 NM |
370 | void led_trigger_register_simple(const char *name, struct led_trigger **tp) |
371 | { | |
eb202621 | 372 | struct led_trigger *trig; |
4d404fd5 | 373 | int err; |
c3bc9956 | 374 | |
eb202621 | 375 | trig = kzalloc(sizeof(struct led_trigger), GFP_KERNEL); |
c3bc9956 | 376 | |
eb202621 BW |
377 | if (trig) { |
378 | trig->name = name; | |
379 | err = led_trigger_register(trig); | |
cba4c2ac | 380 | if (err < 0) { |
eb202621 BW |
381 | kfree(trig); |
382 | trig = NULL; | |
09f5fe75 SK |
383 | pr_warn("LED trigger %s failed to register (%d)\n", |
384 | name, err); | |
cba4c2ac | 385 | } |
09f5fe75 SK |
386 | } else { |
387 | pr_warn("LED trigger %s failed to register (no memory)\n", | |
388 | name); | |
389 | } | |
eb202621 | 390 | *tp = trig; |
4d404fd5 | 391 | } |
c3bc9956 | 392 | EXPORT_SYMBOL_GPL(led_trigger_register_simple); |
4d404fd5 | 393 | |
eb202621 | 394 | void led_trigger_unregister_simple(struct led_trigger *trig) |
4d404fd5 | 395 | { |
eb202621 BW |
396 | if (trig) |
397 | led_trigger_unregister(trig); | |
398 | kfree(trig); | |
4d404fd5 | 399 | } |
c3bc9956 | 400 | EXPORT_SYMBOL_GPL(led_trigger_unregister_simple); |