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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * LED Flash class interface
4 *
5 * Copyright (C) 2015 Samsung Electronics Co., Ltd.
6 * Author: Jacek Anaszewski <[email protected]>
7 */
8
9#include <linux/device.h>
10#include <linux/init.h>
11#include <linux/led-class-flash.h>
12#include <linux/leds.h>
13#include <linux/module.h>
14#include <linux/slab.h>
15
16#define has_flash_op(fled_cdev, op) \
17 (fled_cdev && fled_cdev->ops->op)
18
19#define call_flash_op(fled_cdev, op, args...) \
20 ((has_flash_op(fled_cdev, op)) ? \
21 (fled_cdev->ops->op(fled_cdev, args)) : \
22 -EINVAL)
23
24static const char * const led_flash_fault_names[] = {
25 "led-over-voltage",
26 "flash-timeout-exceeded",
27 "controller-over-temperature",
28 "controller-short-circuit",
29 "led-power-supply-over-current",
30 "indicator-led-fault",
31 "led-under-voltage",
32 "controller-under-voltage",
33 "led-over-temperature",
34};
35
36static ssize_t flash_brightness_store(struct device *dev,
37 struct device_attribute *attr, const char *buf, size_t size)
38{
39 struct led_classdev *led_cdev = dev_get_drvdata(dev);
40 struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
41 unsigned long state;
42 ssize_t ret;
43
44 mutex_lock(&led_cdev->led_access);
45
46 if (led_sysfs_is_disabled(led_cdev)) {
47 ret = -EBUSY;
48 goto unlock;
49 }
50
51 ret = kstrtoul(buf, 10, &state);
52 if (ret)
53 goto unlock;
54
55 ret = led_set_flash_brightness(fled_cdev, state);
56 if (ret < 0)
57 goto unlock;
58
59 ret = size;
60unlock:
61 mutex_unlock(&led_cdev->led_access);
62 return ret;
63}
64
65static ssize_t flash_brightness_show(struct device *dev,
66 struct device_attribute *attr, char *buf)
67{
68 struct led_classdev *led_cdev = dev_get_drvdata(dev);
69 struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
70
71 /* no lock needed for this */
72 led_update_flash_brightness(fled_cdev);
73
74 return sprintf(buf, "%u\n", fled_cdev->brightness.val);
75}
76static DEVICE_ATTR_RW(flash_brightness);
77
78static ssize_t max_flash_brightness_show(struct device *dev,
79 struct device_attribute *attr, char *buf)
80{
81 struct led_classdev *led_cdev = dev_get_drvdata(dev);
82 struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
83
84 return sprintf(buf, "%u\n", fled_cdev->brightness.max);
85}
86static DEVICE_ATTR_RO(max_flash_brightness);
87
88static ssize_t flash_strobe_store(struct device *dev,
89 struct device_attribute *attr, const char *buf, size_t size)
90{
91 struct led_classdev *led_cdev = dev_get_drvdata(dev);
92 struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
93 unsigned long state;
94 ssize_t ret = -EBUSY;
95
96 mutex_lock(&led_cdev->led_access);
97
98 if (led_sysfs_is_disabled(led_cdev))
99 goto unlock;
100
101 ret = kstrtoul(buf, 10, &state);
102 if (ret)
103 goto unlock;
104
105 if (state > 1) {
106 ret = -EINVAL;
107 goto unlock;
108 }
109
110 ret = led_set_flash_strobe(fled_cdev, state);
111 if (ret < 0)
112 goto unlock;
113 ret = size;
114unlock:
115 mutex_unlock(&led_cdev->led_access);
116 return ret;
117}
118
119static ssize_t flash_strobe_show(struct device *dev,
120 struct device_attribute *attr, char *buf)
121{
122 struct led_classdev *led_cdev = dev_get_drvdata(dev);
123 struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
124 bool state;
125 int ret;
126
127 /* no lock needed for this */
128 ret = led_get_flash_strobe(fled_cdev, &state);
129 if (ret < 0)
130 return ret;
131
132 return sprintf(buf, "%u\n", state);
133}
134static DEVICE_ATTR_RW(flash_strobe);
135
136static ssize_t flash_timeout_store(struct device *dev,
137 struct device_attribute *attr, const char *buf, size_t size)
138{
139 struct led_classdev *led_cdev = dev_get_drvdata(dev);
140 struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
141 unsigned long flash_timeout;
142 ssize_t ret;
143
144 mutex_lock(&led_cdev->led_access);
145
146 if (led_sysfs_is_disabled(led_cdev)) {
147 ret = -EBUSY;
148 goto unlock;
149 }
150
151 ret = kstrtoul(buf, 10, &flash_timeout);
152 if (ret)
153 goto unlock;
154
155 ret = led_set_flash_timeout(fled_cdev, flash_timeout);
156 if (ret < 0)
157 goto unlock;
158
159 ret = size;
160unlock:
161 mutex_unlock(&led_cdev->led_access);
162 return ret;
163}
164
165static ssize_t flash_timeout_show(struct device *dev,
166 struct device_attribute *attr, char *buf)
167{
168 struct led_classdev *led_cdev = dev_get_drvdata(dev);
169 struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
170
171 return sprintf(buf, "%u\n", fled_cdev->timeout.val);
172}
173static DEVICE_ATTR_RW(flash_timeout);
174
175static ssize_t max_flash_timeout_show(struct device *dev,
176 struct device_attribute *attr, char *buf)
177{
178 struct led_classdev *led_cdev = dev_get_drvdata(dev);
179 struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
180
181 return sprintf(buf, "%u\n", fled_cdev->timeout.max);
182}
183static DEVICE_ATTR_RO(max_flash_timeout);
184
185static ssize_t flash_fault_show(struct device *dev,
186 struct device_attribute *attr, char *buf)
187{
188 struct led_classdev *led_cdev = dev_get_drvdata(dev);
189 struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
190 u32 fault, mask = 0x1;
191 char *pbuf = buf;
192 int i, ret, buf_len;
193
194 ret = led_get_flash_fault(fled_cdev, &fault);
195 if (ret < 0)
196 return -EINVAL;
197
198 *buf = '\0';
199
200 for (i = 0; i < LED_NUM_FLASH_FAULTS; ++i) {
201 if (fault & mask) {
202 buf_len = sprintf(pbuf, "%s ",
203 led_flash_fault_names[i]);
204 pbuf += buf_len;
205 }
206 mask <<= 1;
207 }
208
209 return strlen(strcat(buf, "\n"));
210}
211static DEVICE_ATTR_RO(flash_fault);
212
213static struct attribute *led_flash_strobe_attrs[] = {
214 &dev_attr_flash_strobe.attr,
215 NULL,
216};
217
218static struct attribute *led_flash_timeout_attrs[] = {
219 &dev_attr_flash_timeout.attr,
220 &dev_attr_max_flash_timeout.attr,
221 NULL,
222};
223
224static struct attribute *led_flash_brightness_attrs[] = {
225 &dev_attr_flash_brightness.attr,
226 &dev_attr_max_flash_brightness.attr,
227 NULL,
228};
229
230static struct attribute *led_flash_fault_attrs[] = {
231 &dev_attr_flash_fault.attr,
232 NULL,
233};
234
235static const struct attribute_group led_flash_strobe_group = {
236 .attrs = led_flash_strobe_attrs,
237};
238
239static const struct attribute_group led_flash_timeout_group = {
240 .attrs = led_flash_timeout_attrs,
241};
242
243static const struct attribute_group led_flash_brightness_group = {
244 .attrs = led_flash_brightness_attrs,
245};
246
247static const struct attribute_group led_flash_fault_group = {
248 .attrs = led_flash_fault_attrs,
249};
250
251static void led_flash_resume(struct led_classdev *led_cdev)
252{
253 struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
254
255 call_flash_op(fled_cdev, flash_brightness_set,
256 fled_cdev->brightness.val);
257 call_flash_op(fled_cdev, timeout_set, fled_cdev->timeout.val);
258}
259
260static void led_flash_init_sysfs_groups(struct led_classdev_flash *fled_cdev)
261{
262 struct led_classdev *led_cdev = &fled_cdev->led_cdev;
263 const struct led_flash_ops *ops = fled_cdev->ops;
264 const struct attribute_group **flash_groups = fled_cdev->sysfs_groups;
265
266 int num_sysfs_groups = 0;
267
268 flash_groups[num_sysfs_groups++] = &led_flash_strobe_group;
269
270 if (ops->flash_brightness_set)
271 flash_groups[num_sysfs_groups++] = &led_flash_brightness_group;
272
273 if (ops->timeout_set)
274 flash_groups[num_sysfs_groups++] = &led_flash_timeout_group;
275
276 if (ops->fault_get)
277 flash_groups[num_sysfs_groups++] = &led_flash_fault_group;
278
279 led_cdev->groups = flash_groups;
280}
281
282int led_classdev_flash_register_ext(struct device *parent,
283 struct led_classdev_flash *fled_cdev,
284 struct led_init_data *init_data)
285{
286 struct led_classdev *led_cdev;
287 const struct led_flash_ops *ops;
288 int ret;
289
290 if (!fled_cdev)
291 return -EINVAL;
292
293 led_cdev = &fled_cdev->led_cdev;
294
295 if (led_cdev->flags & LED_DEV_CAP_FLASH) {
296 if (!led_cdev->brightness_set_blocking)
297 return -EINVAL;
298
299 ops = fled_cdev->ops;
300 if (!ops || !ops->strobe_set)
301 return -EINVAL;
302
303 led_cdev->flash_resume = led_flash_resume;
304
305 /* Select the sysfs attributes to be created for the device */
306 led_flash_init_sysfs_groups(fled_cdev);
307 }
308
309 /* Register led class device */
310 ret = led_classdev_register_ext(parent, led_cdev, init_data);
311 if (ret < 0)
312 return ret;
313
314 return 0;
315}
316EXPORT_SYMBOL_GPL(led_classdev_flash_register_ext);
317
318void led_classdev_flash_unregister(struct led_classdev_flash *fled_cdev)
319{
320 if (!fled_cdev)
321 return;
322
323 led_classdev_unregister(&fled_cdev->led_cdev);
324}
325EXPORT_SYMBOL_GPL(led_classdev_flash_unregister);
326
327static void devm_led_classdev_flash_release(struct device *dev, void *res)
328{
329 led_classdev_flash_unregister(*(struct led_classdev_flash **)res);
330}
331
332int devm_led_classdev_flash_register_ext(struct device *parent,
333 struct led_classdev_flash *fled_cdev,
334 struct led_init_data *init_data)
335{
336 struct led_classdev_flash **dr;
337 int ret;
338
339 dr = devres_alloc(devm_led_classdev_flash_release, sizeof(*dr),
340 GFP_KERNEL);
341 if (!dr)
342 return -ENOMEM;
343
344 ret = led_classdev_flash_register_ext(parent, fled_cdev, init_data);
345 if (ret) {
346 devres_free(dr);
347 return ret;
348 }
349
350 *dr = fled_cdev;
351 devres_add(parent, dr);
352
353 return 0;
354}
355EXPORT_SYMBOL_GPL(devm_led_classdev_flash_register_ext);
356
357static int devm_led_classdev_flash_match(struct device *dev,
358 void *res, void *data)
359{
360 struct led_classdev_flash **p = res;
361
362 if (WARN_ON(!p || !*p))
363 return 0;
364
365 return *p == data;
366}
367
368void devm_led_classdev_flash_unregister(struct device *dev,
369 struct led_classdev_flash *fled_cdev)
370{
371 WARN_ON(devres_release(dev,
372 devm_led_classdev_flash_release,
373 devm_led_classdev_flash_match, fled_cdev));
374}
375EXPORT_SYMBOL_GPL(devm_led_classdev_flash_unregister);
376
377static void led_clamp_align(struct led_flash_setting *s)
378{
379 u32 v, offset;
380
381 v = s->val + s->step / 2;
382 v = clamp(v, s->min, s->max);
383 offset = v - s->min;
384 offset = s->step * (offset / s->step);
385 s->val = s->min + offset;
386}
387
388int led_set_flash_timeout(struct led_classdev_flash *fled_cdev, u32 timeout)
389{
390 struct led_classdev *led_cdev = &fled_cdev->led_cdev;
391 struct led_flash_setting *s = &fled_cdev->timeout;
392
393 s->val = timeout;
394 led_clamp_align(s);
395
396 if (!(led_cdev->flags & LED_SUSPENDED))
397 return call_flash_op(fled_cdev, timeout_set, s->val);
398
399 return 0;
400}
401EXPORT_SYMBOL_GPL(led_set_flash_timeout);
402
403int led_get_flash_fault(struct led_classdev_flash *fled_cdev, u32 *fault)
404{
405 return call_flash_op(fled_cdev, fault_get, fault);
406}
407EXPORT_SYMBOL_GPL(led_get_flash_fault);
408
409int led_set_flash_brightness(struct led_classdev_flash *fled_cdev,
410 u32 brightness)
411{
412 struct led_classdev *led_cdev = &fled_cdev->led_cdev;
413 struct led_flash_setting *s = &fled_cdev->brightness;
414
415 s->val = brightness;
416 led_clamp_align(s);
417
418 if (!(led_cdev->flags & LED_SUSPENDED))
419 return call_flash_op(fled_cdev, flash_brightness_set, s->val);
420
421 return 0;
422}
423EXPORT_SYMBOL_GPL(led_set_flash_brightness);
424
425int led_update_flash_brightness(struct led_classdev_flash *fled_cdev)
426{
427 struct led_flash_setting *s = &fled_cdev->brightness;
428 u32 brightness;
429
430 if (has_flash_op(fled_cdev, flash_brightness_get)) {
431 int ret = call_flash_op(fled_cdev, flash_brightness_get,
432 &brightness);
433 if (ret < 0)
434 return ret;
435
436 s->val = brightness;
437 }
438
439 return 0;
440}
441EXPORT_SYMBOL_GPL(led_update_flash_brightness);
442
443int led_set_flash_duration(struct led_classdev_flash *fled_cdev, u32 duration)
444{
445 struct led_classdev *led_cdev = &fled_cdev->led_cdev;
446 struct led_flash_setting *s = &fled_cdev->duration;
447
448 s->val = duration;
449 led_clamp_align(s);
450
451 if (!(led_cdev->flags & LED_SUSPENDED))
452 return call_flash_op(fled_cdev, duration_set, s->val);
453
454 return 0;
455}
456EXPORT_SYMBOL_GPL(led_set_flash_duration);
457
458MODULE_AUTHOR("Jacek Anaszewski <[email protected]>");
459MODULE_DESCRIPTION("LED Flash class interface");
460MODULE_LICENSE("GPL v2");