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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * LED Class Core
4 *
5 * Copyright 2005-2006 Openedhand Ltd.
6 *
7 * Author: Richard Purdie <rpurdie@openedhand.com>
8 */
9
10#include <linux/kernel.h>
11#include <linux/led-class-multicolor.h>
12#include <linux/leds.h>
13#include <linux/list.h>
14#include <linux/module.h>
15#include <linux/mutex.h>
16#include <linux/of.h>
17#include <linux/property.h>
18#include <linux/rwsem.h>
19#include <linux/slab.h>
20#include <uapi/linux/uleds.h>
21#include "leds.h"
22
23DECLARE_RWSEM(leds_list_lock);
24EXPORT_SYMBOL_GPL(leds_list_lock);
25
26LIST_HEAD(leds_list);
27EXPORT_SYMBOL_GPL(leds_list);
28
29static const char * const led_colors[LED_COLOR_ID_MAX] = {
30 [LED_COLOR_ID_WHITE] = "white",
31 [LED_COLOR_ID_RED] = "red",
32 [LED_COLOR_ID_GREEN] = "green",
33 [LED_COLOR_ID_BLUE] = "blue",
34 [LED_COLOR_ID_AMBER] = "amber",
35 [LED_COLOR_ID_VIOLET] = "violet",
36 [LED_COLOR_ID_YELLOW] = "yellow",
37 [LED_COLOR_ID_IR] = "ir",
38 [LED_COLOR_ID_MULTI] = "multicolor",
39 [LED_COLOR_ID_RGB] = "rgb",
40 [LED_COLOR_ID_PURPLE] = "purple",
41 [LED_COLOR_ID_ORANGE] = "orange",
42 [LED_COLOR_ID_PINK] = "pink",
43 [LED_COLOR_ID_CYAN] = "cyan",
44 [LED_COLOR_ID_LIME] = "lime",
45};
46
47static int __led_set_brightness(struct led_classdev *led_cdev, unsigned int value)
48{
49 if (!led_cdev->brightness_set)
50 return -ENOTSUPP;
51
52 led_cdev->brightness_set(led_cdev, value);
53
54 return 0;
55}
56
57static int __led_set_brightness_blocking(struct led_classdev *led_cdev, unsigned int value)
58{
59 if (!led_cdev->brightness_set_blocking)
60 return -ENOTSUPP;
61
62 return led_cdev->brightness_set_blocking(led_cdev, value);
63}
64
65static void led_timer_function(struct timer_list *t)
66{
67 struct led_classdev *led_cdev = from_timer(led_cdev, t, blink_timer);
68 unsigned long brightness;
69 unsigned long delay;
70
71 if (!led_cdev->blink_delay_on || !led_cdev->blink_delay_off) {
72 led_set_brightness_nosleep(led_cdev, LED_OFF);
73 clear_bit(LED_BLINK_SW, &led_cdev->work_flags);
74 return;
75 }
76
77 if (test_and_clear_bit(LED_BLINK_ONESHOT_STOP,
78 &led_cdev->work_flags)) {
79 clear_bit(LED_BLINK_SW, &led_cdev->work_flags);
80 return;
81 }
82
83 brightness = led_get_brightness(led_cdev);
84 if (!brightness) {
85 /* Time to switch the LED on. */
86 if (test_and_clear_bit(LED_BLINK_BRIGHTNESS_CHANGE,
87 &led_cdev->work_flags))
88 brightness = led_cdev->new_blink_brightness;
89 else
90 brightness = led_cdev->blink_brightness;
91 delay = led_cdev->blink_delay_on;
92 } else {
93 /* Store the current brightness value to be able
94 * to restore it when the delay_off period is over.
95 */
96 led_cdev->blink_brightness = brightness;
97 brightness = LED_OFF;
98 delay = led_cdev->blink_delay_off;
99 }
100
101 led_set_brightness_nosleep(led_cdev, brightness);
102
103 /* Return in next iteration if led is in one-shot mode and we are in
104 * the final blink state so that the led is toggled each delay_on +
105 * delay_off milliseconds in worst case.
106 */
107 if (test_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags)) {
108 if (test_bit(LED_BLINK_INVERT, &led_cdev->work_flags)) {
109 if (brightness)
110 set_bit(LED_BLINK_ONESHOT_STOP,
111 &led_cdev->work_flags);
112 } else {
113 if (!brightness)
114 set_bit(LED_BLINK_ONESHOT_STOP,
115 &led_cdev->work_flags);
116 }
117 }
118
119 mod_timer(&led_cdev->blink_timer, jiffies + msecs_to_jiffies(delay));
120}
121
122static void set_brightness_delayed_set_brightness(struct led_classdev *led_cdev,
123 unsigned int value)
124{
125 int ret;
126
127 ret = __led_set_brightness(led_cdev, value);
128 if (ret == -ENOTSUPP) {
129 ret = __led_set_brightness_blocking(led_cdev, value);
130 if (ret == -ENOTSUPP)
131 /* No back-end support to set a fixed brightness value */
132 return;
133 }
134
135 /* LED HW might have been unplugged, therefore don't warn */
136 if (ret == -ENODEV && led_cdev->flags & LED_UNREGISTERING &&
137 led_cdev->flags & LED_HW_PLUGGABLE)
138 return;
139
140 if (ret < 0)
141 dev_err(led_cdev->dev,
142 "Setting an LED's brightness failed (%d)\n", ret);
143}
144
145static void set_brightness_delayed(struct work_struct *ws)
146{
147 struct led_classdev *led_cdev =
148 container_of(ws, struct led_classdev, set_brightness_work);
149
150 if (test_and_clear_bit(LED_BLINK_DISABLE, &led_cdev->work_flags)) {
151 led_stop_software_blink(led_cdev);
152 set_bit(LED_SET_BRIGHTNESS_OFF, &led_cdev->work_flags);
153 }
154
155 /*
156 * Triggers may call led_set_brightness(LED_OFF),
157 * led_set_brightness(LED_FULL) in quick succession to disable blinking
158 * and turn the LED on. Both actions may have been scheduled to run
159 * before this work item runs once. To make sure this works properly
160 * handle LED_SET_BRIGHTNESS_OFF first.
161 */
162 if (test_and_clear_bit(LED_SET_BRIGHTNESS_OFF, &led_cdev->work_flags))
163 set_brightness_delayed_set_brightness(led_cdev, LED_OFF);
164
165 if (test_and_clear_bit(LED_SET_BRIGHTNESS, &led_cdev->work_flags))
166 set_brightness_delayed_set_brightness(led_cdev, led_cdev->delayed_set_value);
167
168 if (test_and_clear_bit(LED_SET_BLINK, &led_cdev->work_flags)) {
169 unsigned long delay_on = led_cdev->delayed_delay_on;
170 unsigned long delay_off = led_cdev->delayed_delay_off;
171
172 led_blink_set(led_cdev, &delay_on, &delay_off);
173 }
174}
175
176static void led_set_software_blink(struct led_classdev *led_cdev,
177 unsigned long delay_on,
178 unsigned long delay_off)
179{
180 int current_brightness;
181
182 current_brightness = led_get_brightness(led_cdev);
183 if (current_brightness)
184 led_cdev->blink_brightness = current_brightness;
185 if (!led_cdev->blink_brightness)
186 led_cdev->blink_brightness = led_cdev->max_brightness;
187
188 led_cdev->blink_delay_on = delay_on;
189 led_cdev->blink_delay_off = delay_off;
190
191 /* never on - just set to off */
192 if (!delay_on) {
193 led_set_brightness_nosleep(led_cdev, LED_OFF);
194 return;
195 }
196
197 /* never off - just set to brightness */
198 if (!delay_off) {
199 led_set_brightness_nosleep(led_cdev,
200 led_cdev->blink_brightness);
201 return;
202 }
203
204 set_bit(LED_BLINK_SW, &led_cdev->work_flags);
205 mod_timer(&led_cdev->blink_timer, jiffies + 1);
206}
207
208
209static void led_blink_setup(struct led_classdev *led_cdev,
210 unsigned long *delay_on,
211 unsigned long *delay_off)
212{
213 if (!test_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags) &&
214 led_cdev->blink_set &&
215 !led_cdev->blink_set(led_cdev, delay_on, delay_off))
216 return;
217
218 /* blink with 1 Hz as default if nothing specified */
219 if (!*delay_on && !*delay_off)
220 *delay_on = *delay_off = 500;
221
222 led_set_software_blink(led_cdev, *delay_on, *delay_off);
223}
224
225void led_init_core(struct led_classdev *led_cdev)
226{
227 INIT_WORK(&led_cdev->set_brightness_work, set_brightness_delayed);
228
229 timer_setup(&led_cdev->blink_timer, led_timer_function, 0);
230}
231EXPORT_SYMBOL_GPL(led_init_core);
232
233void led_blink_set(struct led_classdev *led_cdev,
234 unsigned long *delay_on,
235 unsigned long *delay_off)
236{
237 del_timer_sync(&led_cdev->blink_timer);
238
239 clear_bit(LED_BLINK_SW, &led_cdev->work_flags);
240 clear_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags);
241 clear_bit(LED_BLINK_ONESHOT_STOP, &led_cdev->work_flags);
242
243 led_blink_setup(led_cdev, delay_on, delay_off);
244}
245EXPORT_SYMBOL_GPL(led_blink_set);
246
247void led_blink_set_oneshot(struct led_classdev *led_cdev,
248 unsigned long *delay_on,
249 unsigned long *delay_off,
250 int invert)
251{
252 if (test_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags) &&
253 timer_pending(&led_cdev->blink_timer))
254 return;
255
256 set_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags);
257 clear_bit(LED_BLINK_ONESHOT_STOP, &led_cdev->work_flags);
258
259 if (invert)
260 set_bit(LED_BLINK_INVERT, &led_cdev->work_flags);
261 else
262 clear_bit(LED_BLINK_INVERT, &led_cdev->work_flags);
263
264 led_blink_setup(led_cdev, delay_on, delay_off);
265}
266EXPORT_SYMBOL_GPL(led_blink_set_oneshot);
267
268void led_blink_set_nosleep(struct led_classdev *led_cdev, unsigned long delay_on,
269 unsigned long delay_off)
270{
271 /* If necessary delegate to a work queue task. */
272 if (led_cdev->blink_set && led_cdev->brightness_set_blocking) {
273 led_cdev->delayed_delay_on = delay_on;
274 led_cdev->delayed_delay_off = delay_off;
275 set_bit(LED_SET_BLINK, &led_cdev->work_flags);
276 queue_work(led_cdev->wq, &led_cdev->set_brightness_work);
277 return;
278 }
279
280 led_blink_set(led_cdev, &delay_on, &delay_off);
281}
282EXPORT_SYMBOL_GPL(led_blink_set_nosleep);
283
284void led_stop_software_blink(struct led_classdev *led_cdev)
285{
286 del_timer_sync(&led_cdev->blink_timer);
287 led_cdev->blink_delay_on = 0;
288 led_cdev->blink_delay_off = 0;
289 clear_bit(LED_BLINK_SW, &led_cdev->work_flags);
290}
291EXPORT_SYMBOL_GPL(led_stop_software_blink);
292
293void led_set_brightness(struct led_classdev *led_cdev, unsigned int brightness)
294{
295 /*
296 * If software blink is active, delay brightness setting
297 * until the next timer tick.
298 */
299 if (test_bit(LED_BLINK_SW, &led_cdev->work_flags)) {
300 /*
301 * If we need to disable soft blinking delegate this to the
302 * work queue task to avoid problems in case we are called
303 * from hard irq context.
304 */
305 if (!brightness) {
306 set_bit(LED_BLINK_DISABLE, &led_cdev->work_flags);
307 queue_work(led_cdev->wq, &led_cdev->set_brightness_work);
308 } else {
309 set_bit(LED_BLINK_BRIGHTNESS_CHANGE,
310 &led_cdev->work_flags);
311 led_cdev->new_blink_brightness = brightness;
312 }
313 return;
314 }
315
316 led_set_brightness_nosleep(led_cdev, brightness);
317}
318EXPORT_SYMBOL_GPL(led_set_brightness);
319
320void led_set_brightness_nopm(struct led_classdev *led_cdev, unsigned int value)
321{
322 /* Use brightness_set op if available, it is guaranteed not to sleep */
323 if (!__led_set_brightness(led_cdev, value))
324 return;
325
326 /*
327 * Brightness setting can sleep, delegate it to a work queue task.
328 * value 0 / LED_OFF is special, since it also disables hw-blinking
329 * (sw-blink disable is handled in led_set_brightness()).
330 * To avoid a hw-blink-disable getting lost when a second brightness
331 * change is done immediately afterwards (before the work runs),
332 * it uses a separate work_flag.
333 */
334 if (value) {
335 led_cdev->delayed_set_value = value;
336 set_bit(LED_SET_BRIGHTNESS, &led_cdev->work_flags);
337 } else {
338 clear_bit(LED_SET_BRIGHTNESS, &led_cdev->work_flags);
339 clear_bit(LED_SET_BLINK, &led_cdev->work_flags);
340 set_bit(LED_SET_BRIGHTNESS_OFF, &led_cdev->work_flags);
341 }
342
343 queue_work(led_cdev->wq, &led_cdev->set_brightness_work);
344}
345EXPORT_SYMBOL_GPL(led_set_brightness_nopm);
346
347void led_set_brightness_nosleep(struct led_classdev *led_cdev, unsigned int value)
348{
349 led_cdev->brightness = min(value, led_cdev->max_brightness);
350
351 if (led_cdev->flags & LED_SUSPENDED)
352 return;
353
354 led_set_brightness_nopm(led_cdev, led_cdev->brightness);
355}
356EXPORT_SYMBOL_GPL(led_set_brightness_nosleep);
357
358int led_set_brightness_sync(struct led_classdev *led_cdev, unsigned int value)
359{
360 if (led_cdev->blink_delay_on || led_cdev->blink_delay_off)
361 return -EBUSY;
362
363 led_cdev->brightness = min(value, led_cdev->max_brightness);
364
365 if (led_cdev->flags & LED_SUSPENDED)
366 return 0;
367
368 return __led_set_brightness_blocking(led_cdev, led_cdev->brightness);
369}
370EXPORT_SYMBOL_GPL(led_set_brightness_sync);
371
372/*
373 * This is a led-core function because just like led_set_brightness()
374 * it is used in the kernel by e.g. triggers.
375 */
376void led_mc_set_brightness(struct led_classdev *led_cdev,
377 unsigned int *intensity_value, unsigned int num_colors,
378 unsigned int brightness)
379{
380 struct led_classdev_mc *mcled_cdev;
381 unsigned int i;
382
383 if (!(led_cdev->flags & LED_MULTI_COLOR)) {
384 dev_err_once(led_cdev->dev, "error not a multi-color LED\n");
385 return;
386 }
387
388 mcled_cdev = lcdev_to_mccdev(led_cdev);
389 if (num_colors != mcled_cdev->num_colors) {
390 dev_err_once(led_cdev->dev, "error num_colors mismatch %u != %u\n",
391 num_colors, mcled_cdev->num_colors);
392 return;
393 }
394
395 for (i = 0; i < mcled_cdev->num_colors; i++)
396 mcled_cdev->subled_info[i].intensity = intensity_value[i];
397
398 led_set_brightness(led_cdev, brightness);
399}
400EXPORT_SYMBOL_GPL(led_mc_set_brightness);
401
402int led_update_brightness(struct led_classdev *led_cdev)
403{
404 int ret;
405
406 if (led_cdev->brightness_get) {
407 ret = led_cdev->brightness_get(led_cdev);
408 if (ret < 0)
409 return ret;
410
411 led_cdev->brightness = ret;
412 }
413
414 return 0;
415}
416EXPORT_SYMBOL_GPL(led_update_brightness);
417
418u32 *led_get_default_pattern(struct led_classdev *led_cdev, unsigned int *size)
419{
420 struct fwnode_handle *fwnode = led_cdev->dev->fwnode;
421 u32 *pattern;
422 int count;
423
424 count = fwnode_property_count_u32(fwnode, "led-pattern");
425 if (count < 0)
426 return NULL;
427
428 pattern = kcalloc(count, sizeof(*pattern), GFP_KERNEL);
429 if (!pattern)
430 return NULL;
431
432 if (fwnode_property_read_u32_array(fwnode, "led-pattern", pattern, count)) {
433 kfree(pattern);
434 return NULL;
435 }
436
437 *size = count;
438
439 return pattern;
440}
441EXPORT_SYMBOL_GPL(led_get_default_pattern);
442
443/* Caller must ensure led_cdev->led_access held */
444void led_sysfs_disable(struct led_classdev *led_cdev)
445{
446 lockdep_assert_held(&led_cdev->led_access);
447
448 led_cdev->flags |= LED_SYSFS_DISABLE;
449}
450EXPORT_SYMBOL_GPL(led_sysfs_disable);
451
452/* Caller must ensure led_cdev->led_access held */
453void led_sysfs_enable(struct led_classdev *led_cdev)
454{
455 lockdep_assert_held(&led_cdev->led_access);
456
457 led_cdev->flags &= ~LED_SYSFS_DISABLE;
458}
459EXPORT_SYMBOL_GPL(led_sysfs_enable);
460
461static void led_parse_fwnode_props(struct device *dev,
462 struct fwnode_handle *fwnode,
463 struct led_properties *props)
464{
465 int ret;
466
467 if (!fwnode)
468 return;
469
470 if (fwnode_property_present(fwnode, "label")) {
471 ret = fwnode_property_read_string(fwnode, "label", &props->label);
472 if (ret)
473 dev_err(dev, "Error parsing 'label' property (%d)\n", ret);
474 return;
475 }
476
477 if (fwnode_property_present(fwnode, "color")) {
478 ret = fwnode_property_read_u32(fwnode, "color", &props->color);
479 if (ret)
480 dev_err(dev, "Error parsing 'color' property (%d)\n", ret);
481 else if (props->color >= LED_COLOR_ID_MAX)
482 dev_err(dev, "LED color identifier out of range\n");
483 else
484 props->color_present = true;
485 }
486
487
488 if (!fwnode_property_present(fwnode, "function"))
489 return;
490
491 ret = fwnode_property_read_string(fwnode, "function", &props->function);
492 if (ret) {
493 dev_err(dev,
494 "Error parsing 'function' property (%d)\n",
495 ret);
496 }
497
498 if (!fwnode_property_present(fwnode, "function-enumerator"))
499 return;
500
501 ret = fwnode_property_read_u32(fwnode, "function-enumerator",
502 &props->func_enum);
503 if (ret) {
504 dev_err(dev,
505 "Error parsing 'function-enumerator' property (%d)\n",
506 ret);
507 } else {
508 props->func_enum_present = true;
509 }
510}
511
512int led_compose_name(struct device *dev, struct led_init_data *init_data,
513 char *led_classdev_name)
514{
515 struct led_properties props = {};
516 struct fwnode_handle *fwnode = init_data->fwnode;
517 const char *devicename = init_data->devicename;
518
519 if (!led_classdev_name)
520 return -EINVAL;
521
522 led_parse_fwnode_props(dev, fwnode, &props);
523
524 if (props.label) {
525 /*
526 * If init_data.devicename is NULL, then it indicates that
527 * DT label should be used as-is for LED class device name.
528 * Otherwise the label is prepended with devicename to compose
529 * the final LED class device name.
530 */
531 if (!devicename) {
532 strscpy(led_classdev_name, props.label,
533 LED_MAX_NAME_SIZE);
534 } else {
535 snprintf(led_classdev_name, LED_MAX_NAME_SIZE, "%s:%s",
536 devicename, props.label);
537 }
538 } else if (props.function || props.color_present) {
539 char tmp_buf[LED_MAX_NAME_SIZE];
540
541 if (props.func_enum_present) {
542 snprintf(tmp_buf, LED_MAX_NAME_SIZE, "%s:%s-%d",
543 props.color_present ? led_colors[props.color] : "",
544 props.function ?: "", props.func_enum);
545 } else {
546 snprintf(tmp_buf, LED_MAX_NAME_SIZE, "%s:%s",
547 props.color_present ? led_colors[props.color] : "",
548 props.function ?: "");
549 }
550 if (init_data->devname_mandatory) {
551 snprintf(led_classdev_name, LED_MAX_NAME_SIZE, "%s:%s",
552 devicename, tmp_buf);
553 } else {
554 strscpy(led_classdev_name, tmp_buf, LED_MAX_NAME_SIZE);
555
556 }
557 } else if (init_data->default_label) {
558 if (!devicename) {
559 dev_err(dev, "Legacy LED naming requires devicename segment");
560 return -EINVAL;
561 }
562 snprintf(led_classdev_name, LED_MAX_NAME_SIZE, "%s:%s",
563 devicename, init_data->default_label);
564 } else if (is_of_node(fwnode)) {
565 strscpy(led_classdev_name, to_of_node(fwnode)->name,
566 LED_MAX_NAME_SIZE);
567 } else
568 return -EINVAL;
569
570 return 0;
571}
572EXPORT_SYMBOL_GPL(led_compose_name);
573
574const char *led_get_color_name(u8 color_id)
575{
576 if (color_id >= ARRAY_SIZE(led_colors))
577 return NULL;
578
579 return led_colors[color_id];
580}
581EXPORT_SYMBOL_GPL(led_get_color_name);
582
583enum led_default_state led_init_default_state_get(struct fwnode_handle *fwnode)
584{
585 const char *state = NULL;
586
587 if (!fwnode_property_read_string(fwnode, "default-state", &state)) {
588 if (!strcmp(state, "keep"))
589 return LEDS_DEFSTATE_KEEP;
590 if (!strcmp(state, "on"))
591 return LEDS_DEFSTATE_ON;
592 }
593
594 return LEDS_DEFSTATE_OFF;
595}
596EXPORT_SYMBOL_GPL(led_init_default_state_get);
1/*
2 * LED Class Core
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/kernel.h>
15#include <linux/leds.h>
16#include <linux/list.h>
17#include <linux/module.h>
18#include <linux/mutex.h>
19#include <linux/rwsem.h>
20#include "leds.h"
21
22DECLARE_RWSEM(leds_list_lock);
23EXPORT_SYMBOL_GPL(leds_list_lock);
24
25LIST_HEAD(leds_list);
26EXPORT_SYMBOL_GPL(leds_list);
27
28static int __led_set_brightness(struct led_classdev *led_cdev,
29 enum led_brightness value)
30{
31 if (!led_cdev->brightness_set)
32 return -ENOTSUPP;
33
34 led_cdev->brightness_set(led_cdev, value);
35
36 return 0;
37}
38
39static int __led_set_brightness_blocking(struct led_classdev *led_cdev,
40 enum led_brightness value)
41{
42 if (!led_cdev->brightness_set_blocking)
43 return -ENOTSUPP;
44
45 return led_cdev->brightness_set_blocking(led_cdev, value);
46}
47
48static void led_timer_function(unsigned long data)
49{
50 struct led_classdev *led_cdev = (void *)data;
51 unsigned long brightness;
52 unsigned long delay;
53
54 if (!led_cdev->blink_delay_on || !led_cdev->blink_delay_off) {
55 led_set_brightness_nosleep(led_cdev, LED_OFF);
56 clear_bit(LED_BLINK_SW, &led_cdev->work_flags);
57 return;
58 }
59
60 if (test_and_clear_bit(LED_BLINK_ONESHOT_STOP,
61 &led_cdev->work_flags)) {
62 clear_bit(LED_BLINK_SW, &led_cdev->work_flags);
63 return;
64 }
65
66 brightness = led_get_brightness(led_cdev);
67 if (!brightness) {
68 /* Time to switch the LED on. */
69 if (test_and_clear_bit(LED_BLINK_BRIGHTNESS_CHANGE,
70 &led_cdev->work_flags))
71 brightness = led_cdev->new_blink_brightness;
72 else
73 brightness = led_cdev->blink_brightness;
74 delay = led_cdev->blink_delay_on;
75 } else {
76 /* Store the current brightness value to be able
77 * to restore it when the delay_off period is over.
78 */
79 led_cdev->blink_brightness = brightness;
80 brightness = LED_OFF;
81 delay = led_cdev->blink_delay_off;
82 }
83
84 led_set_brightness_nosleep(led_cdev, brightness);
85
86 /* Return in next iteration if led is in one-shot mode and we are in
87 * the final blink state so that the led is toggled each delay_on +
88 * delay_off milliseconds in worst case.
89 */
90 if (test_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags)) {
91 if (test_bit(LED_BLINK_INVERT, &led_cdev->work_flags)) {
92 if (brightness)
93 set_bit(LED_BLINK_ONESHOT_STOP,
94 &led_cdev->work_flags);
95 } else {
96 if (!brightness)
97 set_bit(LED_BLINK_ONESHOT_STOP,
98 &led_cdev->work_flags);
99 }
100 }
101
102 mod_timer(&led_cdev->blink_timer, jiffies + msecs_to_jiffies(delay));
103}
104
105static void set_brightness_delayed(struct work_struct *ws)
106{
107 struct led_classdev *led_cdev =
108 container_of(ws, struct led_classdev, set_brightness_work);
109 int ret = 0;
110
111 if (test_and_clear_bit(LED_BLINK_DISABLE, &led_cdev->work_flags)) {
112 led_cdev->delayed_set_value = LED_OFF;
113 led_stop_software_blink(led_cdev);
114 }
115
116 ret = __led_set_brightness(led_cdev, led_cdev->delayed_set_value);
117 if (ret == -ENOTSUPP)
118 ret = __led_set_brightness_blocking(led_cdev,
119 led_cdev->delayed_set_value);
120 if (ret < 0 &&
121 /* LED HW might have been unplugged, therefore don't warn */
122 !(ret == -ENODEV && (led_cdev->flags & LED_UNREGISTERING) &&
123 (led_cdev->flags & LED_HW_PLUGGABLE)))
124 dev_err(led_cdev->dev,
125 "Setting an LED's brightness failed (%d)\n", ret);
126}
127
128static void led_set_software_blink(struct led_classdev *led_cdev,
129 unsigned long delay_on,
130 unsigned long delay_off)
131{
132 int current_brightness;
133
134 current_brightness = led_get_brightness(led_cdev);
135 if (current_brightness)
136 led_cdev->blink_brightness = current_brightness;
137 if (!led_cdev->blink_brightness)
138 led_cdev->blink_brightness = led_cdev->max_brightness;
139
140 led_cdev->blink_delay_on = delay_on;
141 led_cdev->blink_delay_off = delay_off;
142
143 /* never on - just set to off */
144 if (!delay_on) {
145 led_set_brightness_nosleep(led_cdev, LED_OFF);
146 return;
147 }
148
149 /* never off - just set to brightness */
150 if (!delay_off) {
151 led_set_brightness_nosleep(led_cdev,
152 led_cdev->blink_brightness);
153 return;
154 }
155
156 set_bit(LED_BLINK_SW, &led_cdev->work_flags);
157 mod_timer(&led_cdev->blink_timer, jiffies + 1);
158}
159
160
161static void led_blink_setup(struct led_classdev *led_cdev,
162 unsigned long *delay_on,
163 unsigned long *delay_off)
164{
165 if (!test_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags) &&
166 led_cdev->blink_set &&
167 !led_cdev->blink_set(led_cdev, delay_on, delay_off))
168 return;
169
170 /* blink with 1 Hz as default if nothing specified */
171 if (!*delay_on && !*delay_off)
172 *delay_on = *delay_off = 500;
173
174 led_set_software_blink(led_cdev, *delay_on, *delay_off);
175}
176
177void led_init_core(struct led_classdev *led_cdev)
178{
179 INIT_WORK(&led_cdev->set_brightness_work, set_brightness_delayed);
180
181 setup_timer(&led_cdev->blink_timer, led_timer_function,
182 (unsigned long)led_cdev);
183}
184EXPORT_SYMBOL_GPL(led_init_core);
185
186void led_blink_set(struct led_classdev *led_cdev,
187 unsigned long *delay_on,
188 unsigned long *delay_off)
189{
190 del_timer_sync(&led_cdev->blink_timer);
191
192 clear_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags);
193 clear_bit(LED_BLINK_ONESHOT_STOP, &led_cdev->work_flags);
194
195 led_blink_setup(led_cdev, delay_on, delay_off);
196}
197EXPORT_SYMBOL_GPL(led_blink_set);
198
199void led_blink_set_oneshot(struct led_classdev *led_cdev,
200 unsigned long *delay_on,
201 unsigned long *delay_off,
202 int invert)
203{
204 if (test_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags) &&
205 timer_pending(&led_cdev->blink_timer))
206 return;
207
208 set_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags);
209 clear_bit(LED_BLINK_ONESHOT_STOP, &led_cdev->work_flags);
210
211 if (invert)
212 set_bit(LED_BLINK_INVERT, &led_cdev->work_flags);
213 else
214 clear_bit(LED_BLINK_INVERT, &led_cdev->work_flags);
215
216 led_blink_setup(led_cdev, delay_on, delay_off);
217}
218EXPORT_SYMBOL_GPL(led_blink_set_oneshot);
219
220void led_stop_software_blink(struct led_classdev *led_cdev)
221{
222 del_timer_sync(&led_cdev->blink_timer);
223 led_cdev->blink_delay_on = 0;
224 led_cdev->blink_delay_off = 0;
225 clear_bit(LED_BLINK_SW, &led_cdev->work_flags);
226}
227EXPORT_SYMBOL_GPL(led_stop_software_blink);
228
229void led_set_brightness(struct led_classdev *led_cdev,
230 enum led_brightness brightness)
231{
232 /*
233 * If software blink is active, delay brightness setting
234 * until the next timer tick.
235 */
236 if (test_bit(LED_BLINK_SW, &led_cdev->work_flags)) {
237 /*
238 * If we need to disable soft blinking delegate this to the
239 * work queue task to avoid problems in case we are called
240 * from hard irq context.
241 */
242 if (brightness == LED_OFF) {
243 set_bit(LED_BLINK_DISABLE, &led_cdev->work_flags);
244 schedule_work(&led_cdev->set_brightness_work);
245 } else {
246 set_bit(LED_BLINK_BRIGHTNESS_CHANGE,
247 &led_cdev->work_flags);
248 led_cdev->new_blink_brightness = brightness;
249 }
250 return;
251 }
252
253 led_set_brightness_nosleep(led_cdev, brightness);
254}
255EXPORT_SYMBOL_GPL(led_set_brightness);
256
257void led_set_brightness_nopm(struct led_classdev *led_cdev,
258 enum led_brightness value)
259{
260 /* Use brightness_set op if available, it is guaranteed not to sleep */
261 if (!__led_set_brightness(led_cdev, value))
262 return;
263
264 /* If brightness setting can sleep, delegate it to a work queue task */
265 led_cdev->delayed_set_value = value;
266 schedule_work(&led_cdev->set_brightness_work);
267}
268EXPORT_SYMBOL_GPL(led_set_brightness_nopm);
269
270void led_set_brightness_nosleep(struct led_classdev *led_cdev,
271 enum led_brightness value)
272{
273 led_cdev->brightness = min(value, led_cdev->max_brightness);
274
275 if (led_cdev->flags & LED_SUSPENDED)
276 return;
277
278 led_set_brightness_nopm(led_cdev, led_cdev->brightness);
279}
280EXPORT_SYMBOL_GPL(led_set_brightness_nosleep);
281
282int led_set_brightness_sync(struct led_classdev *led_cdev,
283 enum led_brightness value)
284{
285 if (led_cdev->blink_delay_on || led_cdev->blink_delay_off)
286 return -EBUSY;
287
288 led_cdev->brightness = min(value, led_cdev->max_brightness);
289
290 if (led_cdev->flags & LED_SUSPENDED)
291 return 0;
292
293 return __led_set_brightness_blocking(led_cdev, led_cdev->brightness);
294}
295EXPORT_SYMBOL_GPL(led_set_brightness_sync);
296
297int led_update_brightness(struct led_classdev *led_cdev)
298{
299 int ret = 0;
300
301 if (led_cdev->brightness_get) {
302 ret = led_cdev->brightness_get(led_cdev);
303 if (ret >= 0) {
304 led_cdev->brightness = ret;
305 return 0;
306 }
307 }
308
309 return ret;
310}
311EXPORT_SYMBOL_GPL(led_update_brightness);
312
313/* Caller must ensure led_cdev->led_access held */
314void led_sysfs_disable(struct led_classdev *led_cdev)
315{
316 lockdep_assert_held(&led_cdev->led_access);
317
318 led_cdev->flags |= LED_SYSFS_DISABLE;
319}
320EXPORT_SYMBOL_GPL(led_sysfs_disable);
321
322/* Caller must ensure led_cdev->led_access held */
323void led_sysfs_enable(struct led_classdev *led_cdev)
324{
325 lockdep_assert_held(&led_cdev->led_access);
326
327 led_cdev->flags &= ~LED_SYSFS_DISABLE;
328}
329EXPORT_SYMBOL_GPL(led_sysfs_enable);