Merge tag 'for-5.20/parisc-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller...
[linux-block.git] / drivers / leds / led-core.c
CommitLineData
d2912cb1 1// SPDX-License-Identifier: GPL-2.0-only
c72a1d60
RP
2/*
3 * LED Class Core
4 *
5 * Copyright 2005-2006 Openedhand Ltd.
6 *
7 * Author: Richard Purdie <rpurdie@openedhand.com>
c72a1d60
RP
8 */
9
10#include <linux/kernel.h>
04713306 11#include <linux/leds.h>
c72a1d60
RP
12#include <linux/list.h>
13#include <linux/module.h>
04713306 14#include <linux/mutex.h>
8e1f4561 15#include <linux/of.h>
bb4e9af0 16#include <linux/property.h>
72f8da32 17#include <linux/rwsem.h>
8e1f4561 18#include <linux/slab.h>
bb4e9af0 19#include <uapi/linux/uleds.h>
c72a1d60
RP
20#include "leds.h"
21
72f8da32 22DECLARE_RWSEM(leds_list_lock);
4d404fd5 23EXPORT_SYMBOL_GPL(leds_list_lock);
c72a1d60 24
4d404fd5 25LIST_HEAD(leds_list);
c72a1d60 26EXPORT_SYMBOL_GPL(leds_list);
a403d930 27
bb4e9af0
JA
28const char * const led_colors[LED_COLOR_ID_MAX] = {
29 [LED_COLOR_ID_WHITE] = "white",
30 [LED_COLOR_ID_RED] = "red",
31 [LED_COLOR_ID_GREEN] = "green",
32 [LED_COLOR_ID_BLUE] = "blue",
33 [LED_COLOR_ID_AMBER] = "amber",
34 [LED_COLOR_ID_VIOLET] = "violet",
35 [LED_COLOR_ID_YELLOW] = "yellow",
36 [LED_COLOR_ID_IR] = "ir",
10d3e0d8 37 [LED_COLOR_ID_MULTI] = "multicolor",
54212f5a 38 [LED_COLOR_ID_RGB] = "rgb",
bb4e9af0
JA
39};
40EXPORT_SYMBOL_GPL(led_colors);
41
af0bfab9 42static int __led_set_brightness(struct led_classdev *led_cdev, unsigned int value)
d4887af9
HK
43{
44 if (!led_cdev->brightness_set)
45 return -ENOTSUPP;
46
47 led_cdev->brightness_set(led_cdev, value);
48
49 return 0;
50}
51
af0bfab9 52static int __led_set_brightness_blocking(struct led_classdev *led_cdev, unsigned int value)
d4887af9
HK
53{
54 if (!led_cdev->brightness_set_blocking)
55 return -ENOTSUPP;
56
57 return led_cdev->brightness_set_blocking(led_cdev, value);
58}
59
49404665 60static void led_timer_function(struct timer_list *t)
757b06ae 61{
49404665 62 struct led_classdev *led_cdev = from_timer(led_cdev, t, blink_timer);
757b06ae
JA
63 unsigned long brightness;
64 unsigned long delay;
65
66 if (!led_cdev->blink_delay_on || !led_cdev->blink_delay_off) {
81fe8e5b 67 led_set_brightness_nosleep(led_cdev, LED_OFF);
a9c6ce57 68 clear_bit(LED_BLINK_SW, &led_cdev->work_flags);
757b06ae
JA
69 return;
70 }
71
a9c6ce57
HG
72 if (test_and_clear_bit(LED_BLINK_ONESHOT_STOP,
73 &led_cdev->work_flags)) {
74 clear_bit(LED_BLINK_SW, &led_cdev->work_flags);
757b06ae
JA
75 return;
76 }
77
78 brightness = led_get_brightness(led_cdev);
79 if (!brightness) {
80 /* Time to switch the LED on. */
eb1610b4
HG
81 if (test_and_clear_bit(LED_BLINK_BRIGHTNESS_CHANGE,
82 &led_cdev->work_flags))
83 brightness = led_cdev->new_blink_brightness;
84 else
85 brightness = led_cdev->blink_brightness;
757b06ae
JA
86 delay = led_cdev->blink_delay_on;
87 } else {
88 /* Store the current brightness value to be able
89 * to restore it when the delay_off period is over.
90 */
eb1610b4 91 led_cdev->blink_brightness = brightness;
757b06ae
JA
92 brightness = LED_OFF;
93 delay = led_cdev->blink_delay_off;
94 }
95
81fe8e5b 96 led_set_brightness_nosleep(led_cdev, brightness);
757b06ae
JA
97
98 /* Return in next iteration if led is in one-shot mode and we are in
99 * the final blink state so that the led is toggled each delay_on +
100 * delay_off milliseconds in worst case.
101 */
a9c6ce57
HG
102 if (test_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags)) {
103 if (test_bit(LED_BLINK_INVERT, &led_cdev->work_flags)) {
757b06ae 104 if (brightness)
a9c6ce57
HG
105 set_bit(LED_BLINK_ONESHOT_STOP,
106 &led_cdev->work_flags);
757b06ae
JA
107 } else {
108 if (!brightness)
a9c6ce57
HG
109 set_bit(LED_BLINK_ONESHOT_STOP,
110 &led_cdev->work_flags);
757b06ae
JA
111 }
112 }
113
114 mod_timer(&led_cdev->blink_timer, jiffies + msecs_to_jiffies(delay));
115}
116
117static void set_brightness_delayed(struct work_struct *ws)
118{
119 struct led_classdev *led_cdev =
120 container_of(ws, struct led_classdev, set_brightness_work);
1afcadfc 121 int ret = 0;
757b06ae 122
a9c6ce57 123 if (test_and_clear_bit(LED_BLINK_DISABLE, &led_cdev->work_flags)) {
f1e80c07
JA
124 led_cdev->delayed_set_value = LED_OFF;
125 led_stop_software_blink(led_cdev);
f1e80c07 126 }
757b06ae 127
d4887af9
HK
128 ret = __led_set_brightness(led_cdev, led_cdev->delayed_set_value);
129 if (ret == -ENOTSUPP)
130 ret = __led_set_brightness_blocking(led_cdev,
131 led_cdev->delayed_set_value);
d84d80f3
HK
132 if (ret < 0 &&
133 /* LED HW might have been unplugged, therefore don't warn */
134 !(ret == -ENODEV && (led_cdev->flags & LED_UNREGISTERING) &&
135 (led_cdev->flags & LED_HW_PLUGGABLE)))
1afcadfc
JA
136 dev_err(led_cdev->dev,
137 "Setting an LED's brightness failed (%d)\n", ret);
757b06ae
JA
138}
139
a403d930
BW
140static void led_set_software_blink(struct led_classdev *led_cdev,
141 unsigned long delay_on,
142 unsigned long delay_off)
143{
144 int current_brightness;
145
146 current_brightness = led_get_brightness(led_cdev);
147 if (current_brightness)
148 led_cdev->blink_brightness = current_brightness;
149 if (!led_cdev->blink_brightness)
150 led_cdev->blink_brightness = led_cdev->max_brightness;
151
a403d930
BW
152 led_cdev->blink_delay_on = delay_on;
153 led_cdev->blink_delay_off = delay_off;
154
8d82fef8
SS
155 /* never on - just set to off */
156 if (!delay_on) {
81fe8e5b 157 led_set_brightness_nosleep(led_cdev, LED_OFF);
a403d930 158 return;
8d82fef8 159 }
a403d930
BW
160
161 /* never off - just set to brightness */
162 if (!delay_off) {
81fe8e5b
JA
163 led_set_brightness_nosleep(led_cdev,
164 led_cdev->blink_brightness);
a403d930
BW
165 return;
166 }
167
a9c6ce57 168 set_bit(LED_BLINK_SW, &led_cdev->work_flags);
9067359f 169 mod_timer(&led_cdev->blink_timer, jiffies + 1);
a403d930
BW
170}
171
172
20c0e6b8 173static void led_blink_setup(struct led_classdev *led_cdev,
5bb629c5
FB
174 unsigned long *delay_on,
175 unsigned long *delay_off)
a403d930 176{
a9c6ce57 177 if (!test_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags) &&
5bb629c5 178 led_cdev->blink_set &&
a403d930
BW
179 !led_cdev->blink_set(led_cdev, delay_on, delay_off))
180 return;
181
182 /* blink with 1 Hz as default if nothing specified */
183 if (!*delay_on && !*delay_off)
184 *delay_on = *delay_off = 500;
185
186 led_set_software_blink(led_cdev, *delay_on, *delay_off);
187}
5bb629c5 188
757b06ae
JA
189void led_init_core(struct led_classdev *led_cdev)
190{
191 INIT_WORK(&led_cdev->set_brightness_work, set_brightness_delayed);
192
49404665 193 timer_setup(&led_cdev->blink_timer, led_timer_function, 0);
757b06ae
JA
194}
195EXPORT_SYMBOL_GPL(led_init_core);
196
5bb629c5
FB
197void led_blink_set(struct led_classdev *led_cdev,
198 unsigned long *delay_on,
199 unsigned long *delay_off)
200{
7b6af2c5 201 del_timer_sync(&led_cdev->blink_timer);
5bb629c5 202
7b6af2c5 203 clear_bit(LED_BLINK_SW, &led_cdev->work_flags);
a9c6ce57
HG
204 clear_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags);
205 clear_bit(LED_BLINK_ONESHOT_STOP, &led_cdev->work_flags);
5bb629c5
FB
206
207 led_blink_setup(led_cdev, delay_on, delay_off);
208}
2806e2ff 209EXPORT_SYMBOL_GPL(led_blink_set);
a403d930 210
5bb629c5
FB
211void led_blink_set_oneshot(struct led_classdev *led_cdev,
212 unsigned long *delay_on,
213 unsigned long *delay_off,
214 int invert)
215{
a9c6ce57 216 if (test_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags) &&
9067359f 217 timer_pending(&led_cdev->blink_timer))
5bb629c5
FB
218 return;
219
a9c6ce57
HG
220 set_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags);
221 clear_bit(LED_BLINK_ONESHOT_STOP, &led_cdev->work_flags);
5bb629c5
FB
222
223 if (invert)
a9c6ce57 224 set_bit(LED_BLINK_INVERT, &led_cdev->work_flags);
5bb629c5 225 else
a9c6ce57 226 clear_bit(LED_BLINK_INVERT, &led_cdev->work_flags);
5bb629c5
FB
227
228 led_blink_setup(led_cdev, delay_on, delay_off);
229}
2806e2ff 230EXPORT_SYMBOL_GPL(led_blink_set_oneshot);
5bb629c5 231
d23a22a7 232void led_stop_software_blink(struct led_classdev *led_cdev)
a403d930 233{
9067359f 234 del_timer_sync(&led_cdev->blink_timer);
43786482
FB
235 led_cdev->blink_delay_on = 0;
236 led_cdev->blink_delay_off = 0;
a9c6ce57 237 clear_bit(LED_BLINK_SW, &led_cdev->work_flags);
d23a22a7
FB
238}
239EXPORT_SYMBOL_GPL(led_stop_software_blink);
240
af0bfab9 241void led_set_brightness(struct led_classdev *led_cdev, unsigned int brightness)
d23a22a7 242{
f1e80c07 243 /*
7cfe749f 244 * If software blink is active, delay brightness setting
f1e80c07
JA
245 * until the next timer tick.
246 */
a9c6ce57 247 if (test_bit(LED_BLINK_SW, &led_cdev->work_flags)) {
f1e80c07
JA
248 /*
249 * If we need to disable soft blinking delegate this to the
250 * work queue task to avoid problems in case we are called
251 * from hard irq context.
252 */
af0bfab9 253 if (!brightness) {
a9c6ce57 254 set_bit(LED_BLINK_DISABLE, &led_cdev->work_flags);
76931edd 255 schedule_work(&led_cdev->set_brightness_work);
f1e80c07 256 } else {
a9c6ce57
HG
257 set_bit(LED_BLINK_BRIGHTNESS_CHANGE,
258 &led_cdev->work_flags);
eb1610b4 259 led_cdev->new_blink_brightness = brightness;
f1e80c07 260 }
d23a22a7
FB
261 return;
262 }
43786482 263
13ae79bb 264 led_set_brightness_nosleep(led_cdev, brightness);
a403d930 265}
2806e2ff 266EXPORT_SYMBOL_GPL(led_set_brightness);
3ef7de53 267
af0bfab9 268void led_set_brightness_nopm(struct led_classdev *led_cdev, unsigned int value)
81fe8e5b
JA
269{
270 /* Use brightness_set op if available, it is guaranteed not to sleep */
d4887af9 271 if (!__led_set_brightness(led_cdev, value))
81fe8e5b 272 return;
81fe8e5b
JA
273
274 /* If brightness setting can sleep, delegate it to a work queue task */
275 led_cdev->delayed_set_value = value;
276 schedule_work(&led_cdev->set_brightness_work);
277}
278EXPORT_SYMBOL_GPL(led_set_brightness_nopm);
279
af0bfab9 280void led_set_brightness_nosleep(struct led_classdev *led_cdev, unsigned int value)
81fe8e5b
JA
281{
282 led_cdev->brightness = min(value, led_cdev->max_brightness);
283
284 if (led_cdev->flags & LED_SUSPENDED)
285 return;
286
287 led_set_brightness_nopm(led_cdev, led_cdev->brightness);
288}
289EXPORT_SYMBOL_GPL(led_set_brightness_nosleep);
290
af0bfab9 291int led_set_brightness_sync(struct led_classdev *led_cdev, unsigned int value)
13ae79bb
JA
292{
293 if (led_cdev->blink_delay_on || led_cdev->blink_delay_off)
294 return -EBUSY;
295
296 led_cdev->brightness = min(value, led_cdev->max_brightness);
297
298 if (led_cdev->flags & LED_SUSPENDED)
299 return 0;
300
d4887af9 301 return __led_set_brightness_blocking(led_cdev, led_cdev->brightness);
13ae79bb
JA
302}
303EXPORT_SYMBOL_GPL(led_set_brightness_sync);
304
3ef7de53
JA
305int led_update_brightness(struct led_classdev *led_cdev)
306{
307 int ret = 0;
308
309 if (led_cdev->brightness_get) {
310 ret = led_cdev->brightness_get(led_cdev);
311 if (ret >= 0) {
312 led_cdev->brightness = ret;
313 return 0;
314 }
315 }
316
317 return ret;
318}
2806e2ff 319EXPORT_SYMBOL_GPL(led_update_brightness);
acd899e4 320
8e1f4561
KK
321u32 *led_get_default_pattern(struct led_classdev *led_cdev, unsigned int *size)
322{
fd81d7e9 323 struct fwnode_handle *fwnode = led_cdev->dev->fwnode;
8e1f4561
KK
324 u32 *pattern;
325 int count;
326
fd81d7e9 327 count = fwnode_property_count_u32(fwnode, "led-pattern");
8e1f4561
KK
328 if (count < 0)
329 return NULL;
330
331 pattern = kcalloc(count, sizeof(*pattern), GFP_KERNEL);
332 if (!pattern)
333 return NULL;
334
fd81d7e9 335 if (fwnode_property_read_u32_array(fwnode, "led-pattern", pattern, count)) {
8e1f4561
KK
336 kfree(pattern);
337 return NULL;
338 }
339
340 *size = count;
341
342 return pattern;
343}
344EXPORT_SYMBOL_GPL(led_get_default_pattern);
345
acd899e4
JA
346/* Caller must ensure led_cdev->led_access held */
347void led_sysfs_disable(struct led_classdev *led_cdev)
348{
349 lockdep_assert_held(&led_cdev->led_access);
350
351 led_cdev->flags |= LED_SYSFS_DISABLE;
352}
353EXPORT_SYMBOL_GPL(led_sysfs_disable);
354
355/* Caller must ensure led_cdev->led_access held */
356void led_sysfs_enable(struct led_classdev *led_cdev)
357{
358 lockdep_assert_held(&led_cdev->led_access);
359
360 led_cdev->flags &= ~LED_SYSFS_DISABLE;
361}
362EXPORT_SYMBOL_GPL(led_sysfs_enable);
bb4e9af0
JA
363
364static void led_parse_fwnode_props(struct device *dev,
365 struct fwnode_handle *fwnode,
366 struct led_properties *props)
367{
368 int ret;
369
370 if (!fwnode)
371 return;
372
373 if (fwnode_property_present(fwnode, "label")) {
374 ret = fwnode_property_read_string(fwnode, "label", &props->label);
375 if (ret)
376 dev_err(dev, "Error parsing 'label' property (%d)\n", ret);
377 return;
378 }
379
380 if (fwnode_property_present(fwnode, "color")) {
381 ret = fwnode_property_read_u32(fwnode, "color", &props->color);
382 if (ret)
383 dev_err(dev, "Error parsing 'color' property (%d)\n", ret);
384 else if (props->color >= LED_COLOR_ID_MAX)
385 dev_err(dev, "LED color identifier out of range\n");
386 else
387 props->color_present = true;
388 }
389
390
391 if (!fwnode_property_present(fwnode, "function"))
392 return;
393
394 ret = fwnode_property_read_string(fwnode, "function", &props->function);
395 if (ret) {
396 dev_err(dev,
397 "Error parsing 'function' property (%d)\n",
398 ret);
399 }
400
401 if (!fwnode_property_present(fwnode, "function-enumerator"))
402 return;
403
404 ret = fwnode_property_read_u32(fwnode, "function-enumerator",
405 &props->func_enum);
406 if (ret) {
407 dev_err(dev,
408 "Error parsing 'function-enumerator' property (%d)\n",
409 ret);
410 } else {
411 props->func_enum_present = true;
412 }
413}
414
415int led_compose_name(struct device *dev, struct led_init_data *init_data,
416 char *led_classdev_name)
417{
418 struct led_properties props = {};
419 struct fwnode_handle *fwnode = init_data->fwnode;
420 const char *devicename = init_data->devicename;
421
77dce3a2
PM
422 /* We want to label LEDs that can produce full range of colors
423 * as RGB, not multicolor */
424 BUG_ON(props.color == LED_COLOR_ID_MULTI);
425
bb4e9af0
JA
426 if (!led_classdev_name)
427 return -EINVAL;
428
429 led_parse_fwnode_props(dev, fwnode, &props);
430
431 if (props.label) {
432 /*
433 * If init_data.devicename is NULL, then it indicates that
434 * DT label should be used as-is for LED class device name.
435 * Otherwise the label is prepended with devicename to compose
436 * the final LED class device name.
437 */
438 if (!devicename) {
439 strscpy(led_classdev_name, props.label,
440 LED_MAX_NAME_SIZE);
441 } else {
442 snprintf(led_classdev_name, LED_MAX_NAME_SIZE, "%s:%s",
443 devicename, props.label);
444 }
445 } else if (props.function || props.color_present) {
446 char tmp_buf[LED_MAX_NAME_SIZE];
447
448 if (props.func_enum_present) {
449 snprintf(tmp_buf, LED_MAX_NAME_SIZE, "%s:%s-%d",
450 props.color_present ? led_colors[props.color] : "",
451 props.function ?: "", props.func_enum);
452 } else {
453 snprintf(tmp_buf, LED_MAX_NAME_SIZE, "%s:%s",
454 props.color_present ? led_colors[props.color] : "",
455 props.function ?: "");
456 }
457 if (init_data->devname_mandatory) {
458 snprintf(led_classdev_name, LED_MAX_NAME_SIZE, "%s:%s",
459 devicename, tmp_buf);
460 } else {
461 strscpy(led_classdev_name, tmp_buf, LED_MAX_NAME_SIZE);
462
463 }
464 } else if (init_data->default_label) {
465 if (!devicename) {
466 dev_err(dev, "Legacy LED naming requires devicename segment");
467 return -EINVAL;
468 }
469 snprintf(led_classdev_name, LED_MAX_NAME_SIZE, "%s:%s",
470 devicename, init_data->default_label);
471 } else if (is_of_node(fwnode)) {
472 strscpy(led_classdev_name, to_of_node(fwnode)->name,
473 LED_MAX_NAME_SIZE);
474 } else
475 return -EINVAL;
476
477 return 0;
478}
479EXPORT_SYMBOL_GPL(led_compose_name);
791bc411
DOH
480
481enum led_default_state led_init_default_state_get(struct fwnode_handle *fwnode)
482{
483 const char *state = NULL;
484
485 if (!fwnode_property_read_string(fwnode, "default-state", &state)) {
486 if (!strcmp(state, "keep"))
487 return LEDS_DEFSTATE_KEEP;
488 if (!strcmp(state, "on"))
489 return LEDS_DEFSTATE_ON;
490 }
491
492 return LEDS_DEFSTATE_OFF;
493}
494EXPORT_SYMBOL_GPL(led_init_default_state_get);