1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * V4L2 flash LED sub-device registration helpers.
4  *
5  *	Copyright (C) 2015 Samsung Electronics Co., Ltd
6  *	Author: Jacek Anaszewski <j.anaszewski@samsung.com>
7  */
8 
9 #include <linux/led-class-flash.h>
10 #include <linux/module.h>
11 #include <linux/mutex.h>
12 #include <linux/property.h>
13 #include <linux/slab.h>
14 #include <linux/types.h>
15 #include <media/v4l2-flash-led-class.h>
16 
17 #define has_flash_op(v4l2_flash, op)				\
18 	(v4l2_flash && v4l2_flash->ops && v4l2_flash->ops->op)
19 
20 #define call_flash_op(v4l2_flash, op, arg)			\
21 		(has_flash_op(v4l2_flash, op) ?			\
22 			v4l2_flash->ops->op(v4l2_flash, arg) :	\
23 			-EINVAL)
24 
25 enum ctrl_init_data_id {
26 	LED_MODE,
27 	TORCH_INTENSITY,
28 	FLASH_INTENSITY,
29 	INDICATOR_INTENSITY,
30 	FLASH_TIMEOUT,
31 	STROBE_SOURCE,
32 	/*
33 	 * Only above values are applicable to
34 	 * the 'ctrls' array in the struct v4l2_flash.
35 	 */
36 	FLASH_STROBE,
37 	STROBE_STOP,
38 	STROBE_STATUS,
39 	FLASH_FAULT,
40 	NUM_FLASH_CTRLS,
41 };
42 
43 static enum led_brightness __intensity_to_led_brightness(
44 					struct v4l2_ctrl *ctrl, s32 intensity)
45 {
46 	intensity -= ctrl->minimum;
47 	intensity /= (u32) ctrl->step;
48 
49 	/*
50 	 * Indicator LEDs, unlike torch LEDs, are turned on/off basing on
51 	 * the state of V4L2_CID_FLASH_INDICATOR_INTENSITY control only.
52 	 * Therefore it must be possible to set it to 0 level which in
53 	 * the LED subsystem reflects LED_OFF state.
54 	 */
55 	if (ctrl->minimum)
56 		++intensity;
57 
58 	return intensity;
59 }
60 
61 static s32 __led_brightness_to_intensity(struct v4l2_ctrl *ctrl,
62 					 enum led_brightness brightness)
63 {
64 	/*
65 	 * Indicator LEDs, unlike torch LEDs, are turned on/off basing on
66 	 * the state of V4L2_CID_FLASH_INDICATOR_INTENSITY control only.
67 	 * Do not decrement brightness read from the LED subsystem for
68 	 * indicator LED as it may equal 0. For torch LEDs this function
69 	 * is called only when V4L2_FLASH_LED_MODE_TORCH is set and the
70 	 * brightness read is guaranteed to be greater than 0. In the mode
71 	 * V4L2_FLASH_LED_MODE_NONE the cached torch intensity value is used.
72 	 */
73 	if (ctrl->id != V4L2_CID_FLASH_INDICATOR_INTENSITY)
74 		--brightness;
75 
76 	return (brightness * ctrl->step) + ctrl->minimum;
77 }
78 
79 static int v4l2_flash_set_led_brightness(struct v4l2_flash *v4l2_flash,
80 					 struct v4l2_ctrl *ctrl)
81 {
82 	struct v4l2_ctrl **ctrls = v4l2_flash->ctrls;
83 	struct led_classdev *led_cdev;
84 	enum led_brightness brightness;
85 
86 	if (has_flash_op(v4l2_flash, intensity_to_led_brightness))
87 		brightness = call_flash_op(v4l2_flash,
88 					intensity_to_led_brightness,
89 					ctrl->val);
90 	else
91 		brightness = __intensity_to_led_brightness(ctrl, ctrl->val);
92 	/*
93 	 * In case a LED Flash class driver provides ops for custom
94 	 * brightness <-> intensity conversion, it also must have defined
95 	 * related v4l2 control step == 1. In such a case a backward conversion
96 	 * from led brightness to v4l2 intensity is required to find out the
97 	 * aligned intensity value.
98 	 */
99 	if (has_flash_op(v4l2_flash, led_brightness_to_intensity))
100 		ctrl->val = call_flash_op(v4l2_flash,
101 					led_brightness_to_intensity,
102 					brightness);
103 
104 	if (ctrl == ctrls[TORCH_INTENSITY]) {
105 		if (ctrls[LED_MODE]->val != V4L2_FLASH_LED_MODE_TORCH)
106 			return 0;
107 
108 		if (WARN_ON_ONCE(!v4l2_flash->fled_cdev))
109 			return -EINVAL;
110 
111 		led_cdev = &v4l2_flash->fled_cdev->led_cdev;
112 	} else {
113 		if (WARN_ON_ONCE(!v4l2_flash->iled_cdev))
114 			return -EINVAL;
115 
116 		led_cdev = v4l2_flash->iled_cdev;
117 	}
118 
119 	return led_set_brightness_sync(led_cdev, brightness);
120 }
121 
122 static int v4l2_flash_update_led_brightness(struct v4l2_flash *v4l2_flash,
123 					struct v4l2_ctrl *ctrl)
124 {
125 	struct v4l2_ctrl **ctrls = v4l2_flash->ctrls;
126 	struct led_classdev *led_cdev;
127 	int ret;
128 
129 	if (ctrl == ctrls[TORCH_INTENSITY]) {
130 		/*
131 		 * Update torch brightness only if in TORCH_MODE. In other modes
132 		 * torch led is turned off, which would spuriously inform the
133 		 * user space that V4L2_CID_FLASH_TORCH_INTENSITY control value
134 		 * has changed to 0.
135 		 */
136 		if (ctrls[LED_MODE]->val != V4L2_FLASH_LED_MODE_TORCH)
137 			return 0;
138 
139 		if (WARN_ON_ONCE(!v4l2_flash->fled_cdev))
140 			return -EINVAL;
141 
142 		led_cdev = &v4l2_flash->fled_cdev->led_cdev;
143 	} else {
144 		if (WARN_ON_ONCE(!v4l2_flash->iled_cdev))
145 			return -EINVAL;
146 
147 		led_cdev = v4l2_flash->iled_cdev;
148 	}
149 
150 	ret = led_update_brightness(led_cdev);
151 	if (ret < 0)
152 		return ret;
153 
154 	if (has_flash_op(v4l2_flash, led_brightness_to_intensity))
155 		ctrl->val = call_flash_op(v4l2_flash,
156 						led_brightness_to_intensity,
157 						led_cdev->brightness);
158 	else
159 		ctrl->val = __led_brightness_to_intensity(ctrl,
160 						led_cdev->brightness);
161 
162 	return 0;
163 }
164 
165 static int v4l2_flash_g_volatile_ctrl(struct v4l2_ctrl *c)
166 {
167 	struct v4l2_flash *v4l2_flash = v4l2_ctrl_to_v4l2_flash(c);
168 	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
169 	bool is_strobing;
170 	int ret;
171 
172 	switch (c->id) {
173 	case V4L2_CID_FLASH_TORCH_INTENSITY:
174 	case V4L2_CID_FLASH_INDICATOR_INTENSITY:
175 		return v4l2_flash_update_led_brightness(v4l2_flash, c);
176 	}
177 
178 	if (!fled_cdev)
179 		return -EINVAL;
180 
181 	switch (c->id) {
182 	case V4L2_CID_FLASH_INTENSITY:
183 		ret = led_update_flash_brightness(fled_cdev);
184 		if (ret < 0)
185 			return ret;
186 		/*
187 		 * No conversion is needed as LED Flash class also uses
188 		 * microamperes for flash intensity units.
189 		 */
190 		c->val = fled_cdev->brightness.val;
191 		return 0;
192 	case V4L2_CID_FLASH_STROBE_STATUS:
193 		ret = led_get_flash_strobe(fled_cdev, &is_strobing);
194 		if (ret < 0)
195 			return ret;
196 		c->val = is_strobing;
197 		return 0;
198 	case V4L2_CID_FLASH_FAULT:
199 		/* LED faults map directly to V4L2 flash faults */
200 		return led_get_flash_fault(fled_cdev, &c->val);
201 	default:
202 		return -EINVAL;
203 	}
204 }
205 
206 static bool __software_strobe_mode_inactive(struct v4l2_ctrl **ctrls)
207 {
208 	return ((ctrls[LED_MODE]->val != V4L2_FLASH_LED_MODE_FLASH) ||
209 		(ctrls[STROBE_SOURCE] && (ctrls[STROBE_SOURCE]->val !=
210 				V4L2_FLASH_STROBE_SOURCE_SOFTWARE)));
211 }
212 
213 static int v4l2_flash_s_ctrl(struct v4l2_ctrl *c)
214 {
215 	struct v4l2_flash *v4l2_flash = v4l2_ctrl_to_v4l2_flash(c);
216 	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
217 	struct led_classdev *led_cdev;
218 	struct v4l2_ctrl **ctrls = v4l2_flash->ctrls;
219 	bool external_strobe;
220 	int ret = 0;
221 
222 	switch (c->id) {
223 	case V4L2_CID_FLASH_TORCH_INTENSITY:
224 	case V4L2_CID_FLASH_INDICATOR_INTENSITY:
225 		return v4l2_flash_set_led_brightness(v4l2_flash, c);
226 	}
227 
228 	if (!fled_cdev)
229 		return -EINVAL;
230 
231 	led_cdev = &fled_cdev->led_cdev;
232 
233 	switch (c->id) {
234 	case V4L2_CID_FLASH_LED_MODE:
235 		switch (c->val) {
236 		case V4L2_FLASH_LED_MODE_NONE:
237 			led_set_brightness_sync(led_cdev, LED_OFF);
238 			return led_set_flash_strobe(fled_cdev, false);
239 		case V4L2_FLASH_LED_MODE_FLASH:
240 			/* Turn the torch LED off */
241 			led_set_brightness_sync(led_cdev, LED_OFF);
242 			if (ctrls[STROBE_SOURCE]) {
243 				external_strobe = (ctrls[STROBE_SOURCE]->val ==
244 					V4L2_FLASH_STROBE_SOURCE_EXTERNAL);
245 
246 				ret = call_flash_op(v4l2_flash,
247 						external_strobe_set,
248 						external_strobe);
249 			}
250 			return ret;
251 		case V4L2_FLASH_LED_MODE_TORCH:
252 			if (ctrls[STROBE_SOURCE]) {
253 				ret = call_flash_op(v4l2_flash,
254 						external_strobe_set,
255 						false);
256 				if (ret < 0)
257 					return ret;
258 			}
259 			/* Stop flash strobing */
260 			ret = led_set_flash_strobe(fled_cdev, false);
261 			if (ret < 0)
262 				return ret;
263 
264 			return v4l2_flash_set_led_brightness(v4l2_flash,
265 							     ctrls[TORCH_INTENSITY]);
266 		}
267 		break;
268 	case V4L2_CID_FLASH_STROBE_SOURCE:
269 		external_strobe = (c->val == V4L2_FLASH_STROBE_SOURCE_EXTERNAL);
270 		/*
271 		 * For some hardware arrangements setting strobe source may
272 		 * affect torch mode. Therefore, if not in the flash mode,
273 		 * cache only this setting. It will be applied upon switching
274 		 * to flash mode.
275 		 */
276 		if (ctrls[LED_MODE]->val != V4L2_FLASH_LED_MODE_FLASH)
277 			return 0;
278 
279 		return call_flash_op(v4l2_flash, external_strobe_set,
280 					external_strobe);
281 	case V4L2_CID_FLASH_STROBE:
282 		if (__software_strobe_mode_inactive(ctrls))
283 			return -EBUSY;
284 		return led_set_flash_strobe(fled_cdev, true);
285 	case V4L2_CID_FLASH_STROBE_STOP:
286 		if (__software_strobe_mode_inactive(ctrls))
287 			return -EBUSY;
288 		return led_set_flash_strobe(fled_cdev, false);
289 	case V4L2_CID_FLASH_TIMEOUT:
290 		/*
291 		 * No conversion is needed as LED Flash class also uses
292 		 * microseconds for flash timeout units.
293 		 */
294 		return led_set_flash_timeout(fled_cdev, c->val);
295 	case V4L2_CID_FLASH_INTENSITY:
296 		/*
297 		 * No conversion is needed as LED Flash class also uses
298 		 * microamperes for flash intensity units.
299 		 */
300 		return led_set_flash_brightness(fled_cdev, c->val);
301 	}
302 
303 	return -EINVAL;
304 }
305 
306 static const struct v4l2_ctrl_ops v4l2_flash_ctrl_ops = {
307 	.g_volatile_ctrl = v4l2_flash_g_volatile_ctrl,
308 	.s_ctrl = v4l2_flash_s_ctrl,
309 };
310 
311 static void __lfs_to_v4l2_ctrl_config(struct led_flash_setting *s,
312 				struct v4l2_ctrl_config *c)
313 {
314 	c->min = s->min;
315 	c->max = s->max;
316 	c->step = s->step;
317 	c->def = s->val;
318 }
319 
320 static void __fill_ctrl_init_data(struct v4l2_flash *v4l2_flash,
321 			  struct v4l2_flash_config *flash_cfg,
322 			  struct v4l2_flash_ctrl_data *ctrl_init_data)
323 {
324 	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
325 	struct led_classdev *led_cdev = fled_cdev ? &fled_cdev->led_cdev : NULL;
326 	struct v4l2_ctrl_config *ctrl_cfg;
327 	u32 mask;
328 
329 	/* Init INDICATOR_INTENSITY ctrl data */
330 	if (v4l2_flash->iled_cdev) {
331 		ctrl_init_data[INDICATOR_INTENSITY].cid =
332 					V4L2_CID_FLASH_INDICATOR_INTENSITY;
333 		ctrl_cfg = &ctrl_init_data[INDICATOR_INTENSITY].config;
334 		__lfs_to_v4l2_ctrl_config(&flash_cfg->intensity,
335 					  ctrl_cfg);
336 		ctrl_cfg->id = V4L2_CID_FLASH_INDICATOR_INTENSITY;
337 		ctrl_cfg->min = 0;
338 		ctrl_cfg->flags = V4L2_CTRL_FLAG_VOLATILE |
339 				  V4L2_CTRL_FLAG_EXECUTE_ON_WRITE;
340 	}
341 
342 	if (!led_cdev || WARN_ON(!(led_cdev->flags & LED_DEV_CAP_FLASH)))
343 		return;
344 
345 	/* Init FLASH_FAULT ctrl data */
346 	if (flash_cfg->flash_faults) {
347 		ctrl_init_data[FLASH_FAULT].cid = V4L2_CID_FLASH_FAULT;
348 		ctrl_cfg = &ctrl_init_data[FLASH_FAULT].config;
349 		ctrl_cfg->id = V4L2_CID_FLASH_FAULT;
350 		ctrl_cfg->max = flash_cfg->flash_faults;
351 		ctrl_cfg->flags = V4L2_CTRL_FLAG_VOLATILE |
352 				  V4L2_CTRL_FLAG_READ_ONLY;
353 	}
354 
355 	/* Init FLASH_LED_MODE ctrl data */
356 	mask = 1 << V4L2_FLASH_LED_MODE_NONE |
357 	       1 << V4L2_FLASH_LED_MODE_TORCH;
358 	if (led_cdev->flags & LED_DEV_CAP_FLASH)
359 		mask |= 1 << V4L2_FLASH_LED_MODE_FLASH;
360 
361 	ctrl_init_data[LED_MODE].cid = V4L2_CID_FLASH_LED_MODE;
362 	ctrl_cfg = &ctrl_init_data[LED_MODE].config;
363 	ctrl_cfg->id = V4L2_CID_FLASH_LED_MODE;
364 	ctrl_cfg->max = V4L2_FLASH_LED_MODE_TORCH;
365 	ctrl_cfg->menu_skip_mask = ~mask;
366 	ctrl_cfg->def = V4L2_FLASH_LED_MODE_NONE;
367 	ctrl_cfg->flags = 0;
368 
369 	/* Init TORCH_INTENSITY ctrl data */
370 	ctrl_init_data[TORCH_INTENSITY].cid = V4L2_CID_FLASH_TORCH_INTENSITY;
371 	ctrl_cfg = &ctrl_init_data[TORCH_INTENSITY].config;
372 	__lfs_to_v4l2_ctrl_config(&flash_cfg->intensity, ctrl_cfg);
373 	ctrl_cfg->id = V4L2_CID_FLASH_TORCH_INTENSITY;
374 	ctrl_cfg->flags = V4L2_CTRL_FLAG_VOLATILE |
375 			  V4L2_CTRL_FLAG_EXECUTE_ON_WRITE;
376 
377 	/* Init FLASH_STROBE ctrl data */
378 	ctrl_init_data[FLASH_STROBE].cid = V4L2_CID_FLASH_STROBE;
379 	ctrl_cfg = &ctrl_init_data[FLASH_STROBE].config;
380 	ctrl_cfg->id = V4L2_CID_FLASH_STROBE;
381 
382 	/* Init STROBE_STOP ctrl data */
383 	ctrl_init_data[STROBE_STOP].cid = V4L2_CID_FLASH_STROBE_STOP;
384 	ctrl_cfg = &ctrl_init_data[STROBE_STOP].config;
385 	ctrl_cfg->id = V4L2_CID_FLASH_STROBE_STOP;
386 
387 	/* Init FLASH_STROBE_SOURCE ctrl data */
388 	if (flash_cfg->has_external_strobe) {
389 		mask = (1 << V4L2_FLASH_STROBE_SOURCE_SOFTWARE) |
390 		       (1 << V4L2_FLASH_STROBE_SOURCE_EXTERNAL);
391 		ctrl_init_data[STROBE_SOURCE].cid =
392 					V4L2_CID_FLASH_STROBE_SOURCE;
393 		ctrl_cfg = &ctrl_init_data[STROBE_SOURCE].config;
394 		ctrl_cfg->id = V4L2_CID_FLASH_STROBE_SOURCE;
395 		ctrl_cfg->max = V4L2_FLASH_STROBE_SOURCE_EXTERNAL;
396 		ctrl_cfg->menu_skip_mask = ~mask;
397 		ctrl_cfg->def = V4L2_FLASH_STROBE_SOURCE_SOFTWARE;
398 	}
399 
400 	/* Init STROBE_STATUS ctrl data */
401 	if (has_flash_op(fled_cdev, strobe_get)) {
402 		ctrl_init_data[STROBE_STATUS].cid =
403 					V4L2_CID_FLASH_STROBE_STATUS;
404 		ctrl_cfg = &ctrl_init_data[STROBE_STATUS].config;
405 		ctrl_cfg->id = V4L2_CID_FLASH_STROBE_STATUS;
406 		ctrl_cfg->flags = V4L2_CTRL_FLAG_VOLATILE |
407 				  V4L2_CTRL_FLAG_READ_ONLY;
408 	}
409 
410 	/* Init FLASH_TIMEOUT ctrl data */
411 	if (has_flash_op(fled_cdev, timeout_set)) {
412 		ctrl_init_data[FLASH_TIMEOUT].cid = V4L2_CID_FLASH_TIMEOUT;
413 		ctrl_cfg = &ctrl_init_data[FLASH_TIMEOUT].config;
414 		__lfs_to_v4l2_ctrl_config(&fled_cdev->timeout, ctrl_cfg);
415 		ctrl_cfg->id = V4L2_CID_FLASH_TIMEOUT;
416 	}
417 
418 	/* Init FLASH_INTENSITY ctrl data */
419 	if (has_flash_op(fled_cdev, flash_brightness_set)) {
420 		ctrl_init_data[FLASH_INTENSITY].cid = V4L2_CID_FLASH_INTENSITY;
421 		ctrl_cfg = &ctrl_init_data[FLASH_INTENSITY].config;
422 		__lfs_to_v4l2_ctrl_config(&fled_cdev->brightness, ctrl_cfg);
423 		ctrl_cfg->id = V4L2_CID_FLASH_INTENSITY;
424 		ctrl_cfg->flags = V4L2_CTRL_FLAG_VOLATILE |
425 				  V4L2_CTRL_FLAG_EXECUTE_ON_WRITE;
426 	}
427 }
428 
429 static int v4l2_flash_init_controls(struct v4l2_flash *v4l2_flash,
430 				struct v4l2_flash_config *flash_cfg)
431 
432 {
433 	struct v4l2_flash_ctrl_data *ctrl_init_data;
434 	struct v4l2_ctrl *ctrl;
435 	struct v4l2_ctrl_config *ctrl_cfg;
436 	int i, ret, num_ctrls = 0;
437 
438 	v4l2_flash->ctrls = devm_kcalloc(v4l2_flash->sd.dev,
439 					STROBE_SOURCE + 1,
440 					sizeof(*v4l2_flash->ctrls),
441 					GFP_KERNEL);
442 	if (!v4l2_flash->ctrls)
443 		return -ENOMEM;
444 
445 	/* allocate memory dynamically so as not to exceed stack frame size */
446 	ctrl_init_data = kcalloc(NUM_FLASH_CTRLS, sizeof(*ctrl_init_data),
447 					GFP_KERNEL);
448 	if (!ctrl_init_data)
449 		return -ENOMEM;
450 
451 	__fill_ctrl_init_data(v4l2_flash, flash_cfg, ctrl_init_data);
452 
453 	for (i = 0; i < NUM_FLASH_CTRLS; ++i)
454 		if (ctrl_init_data[i].cid)
455 			++num_ctrls;
456 
457 	v4l2_ctrl_handler_init(&v4l2_flash->hdl, num_ctrls);
458 
459 	for (i = 0; i < NUM_FLASH_CTRLS; ++i) {
460 		ctrl_cfg = &ctrl_init_data[i].config;
461 		if (!ctrl_init_data[i].cid)
462 			continue;
463 
464 		if (ctrl_cfg->id == V4L2_CID_FLASH_LED_MODE ||
465 		    ctrl_cfg->id == V4L2_CID_FLASH_STROBE_SOURCE)
466 			ctrl = v4l2_ctrl_new_std_menu(&v4l2_flash->hdl,
467 						&v4l2_flash_ctrl_ops,
468 						ctrl_cfg->id,
469 						ctrl_cfg->max,
470 						ctrl_cfg->menu_skip_mask,
471 						ctrl_cfg->def);
472 		else
473 			ctrl = v4l2_ctrl_new_std(&v4l2_flash->hdl,
474 						&v4l2_flash_ctrl_ops,
475 						ctrl_cfg->id,
476 						ctrl_cfg->min,
477 						ctrl_cfg->max,
478 						ctrl_cfg->step,
479 						ctrl_cfg->def);
480 
481 		if (ctrl)
482 			ctrl->flags |= ctrl_cfg->flags;
483 
484 		if (i <= STROBE_SOURCE)
485 			v4l2_flash->ctrls[i] = ctrl;
486 	}
487 
488 	kfree(ctrl_init_data);
489 
490 	if (v4l2_flash->hdl.error) {
491 		ret = v4l2_flash->hdl.error;
492 		goto error_free_handler;
493 	}
494 
495 	v4l2_ctrl_handler_setup(&v4l2_flash->hdl);
496 
497 	v4l2_flash->sd.ctrl_handler = &v4l2_flash->hdl;
498 
499 	return 0;
500 
501 error_free_handler:
502 	v4l2_ctrl_handler_free(&v4l2_flash->hdl);
503 	return ret;
504 }
505 
506 static int __sync_device_with_v4l2_controls(struct v4l2_flash *v4l2_flash)
507 {
508 	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
509 	struct v4l2_ctrl **ctrls = v4l2_flash->ctrls;
510 	int ret = 0;
511 
512 	if (ctrls[TORCH_INTENSITY]) {
513 		ret = v4l2_flash_set_led_brightness(v4l2_flash,
514 						    ctrls[TORCH_INTENSITY]);
515 		if (ret < 0)
516 			return ret;
517 	}
518 
519 	if (ctrls[INDICATOR_INTENSITY]) {
520 		ret = v4l2_flash_set_led_brightness(v4l2_flash,
521 						    ctrls[INDICATOR_INTENSITY]);
522 		if (ret < 0)
523 			return ret;
524 	}
525 
526 	if (ctrls[FLASH_TIMEOUT]) {
527 		if (WARN_ON_ONCE(!fled_cdev))
528 			return -EINVAL;
529 
530 		ret = led_set_flash_timeout(fled_cdev,
531 					ctrls[FLASH_TIMEOUT]->val);
532 		if (ret < 0)
533 			return ret;
534 	}
535 
536 	if (ctrls[FLASH_INTENSITY]) {
537 		if (WARN_ON_ONCE(!fled_cdev))
538 			return -EINVAL;
539 
540 		ret = led_set_flash_brightness(fled_cdev,
541 					ctrls[FLASH_INTENSITY]->val);
542 		if (ret < 0)
543 			return ret;
544 	}
545 
546 	/*
547 	 * For some hardware arrangements setting strobe source may affect
548 	 * torch mode. Synchronize strobe source setting only if not in torch
549 	 * mode. For torch mode case it will get synchronized upon switching
550 	 * to flash mode.
551 	 */
552 	if (ctrls[STROBE_SOURCE] &&
553 	    ctrls[LED_MODE]->val != V4L2_FLASH_LED_MODE_TORCH)
554 		ret = call_flash_op(v4l2_flash, external_strobe_set,
555 					ctrls[STROBE_SOURCE]->val);
556 
557 	return ret;
558 }
559 
560 /*
561  * V4L2 subdev internal operations
562  */
563 
564 static int v4l2_flash_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
565 {
566 	struct v4l2_flash *v4l2_flash = v4l2_subdev_to_v4l2_flash(sd);
567 	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
568 	struct led_classdev *led_cdev = fled_cdev ? &fled_cdev->led_cdev : NULL;
569 	struct led_classdev *led_cdev_ind = v4l2_flash->iled_cdev;
570 	int ret = 0;
571 
572 	if (!v4l2_fh_is_singular(&fh->vfh))
573 		return 0;
574 
575 	if (led_cdev) {
576 		mutex_lock(&led_cdev->led_access);
577 
578 		led_sysfs_disable(led_cdev);
579 		led_trigger_remove(led_cdev);
580 
581 		mutex_unlock(&led_cdev->led_access);
582 	}
583 
584 	if (led_cdev_ind) {
585 		mutex_lock(&led_cdev_ind->led_access);
586 
587 		led_sysfs_disable(led_cdev_ind);
588 		led_trigger_remove(led_cdev_ind);
589 
590 		mutex_unlock(&led_cdev_ind->led_access);
591 	}
592 
593 	ret = __sync_device_with_v4l2_controls(v4l2_flash);
594 	if (ret < 0)
595 		goto out_sync_device;
596 
597 	return 0;
598 out_sync_device:
599 	if (led_cdev) {
600 		mutex_lock(&led_cdev->led_access);
601 		led_sysfs_enable(led_cdev);
602 		mutex_unlock(&led_cdev->led_access);
603 	}
604 
605 	if (led_cdev_ind) {
606 		mutex_lock(&led_cdev_ind->led_access);
607 		led_sysfs_enable(led_cdev_ind);
608 		mutex_unlock(&led_cdev_ind->led_access);
609 	}
610 
611 	return ret;
612 }
613 
614 static int v4l2_flash_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
615 {
616 	struct v4l2_flash *v4l2_flash = v4l2_subdev_to_v4l2_flash(sd);
617 	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
618 	struct led_classdev *led_cdev = fled_cdev ? &fled_cdev->led_cdev : NULL;
619 	struct led_classdev *led_cdev_ind = v4l2_flash->iled_cdev;
620 	int ret = 0;
621 
622 	if (!v4l2_fh_is_singular(&fh->vfh))
623 		return 0;
624 
625 	if (led_cdev) {
626 		mutex_lock(&led_cdev->led_access);
627 
628 		if (v4l2_flash->ctrls[STROBE_SOURCE])
629 			ret = v4l2_ctrl_s_ctrl(
630 				v4l2_flash->ctrls[STROBE_SOURCE],
631 				V4L2_FLASH_STROBE_SOURCE_SOFTWARE);
632 		led_sysfs_enable(led_cdev);
633 
634 		mutex_unlock(&led_cdev->led_access);
635 	}
636 
637 	if (led_cdev_ind) {
638 		mutex_lock(&led_cdev_ind->led_access);
639 		led_sysfs_enable(led_cdev_ind);
640 		mutex_unlock(&led_cdev_ind->led_access);
641 	}
642 
643 	return ret;
644 }
645 
646 static const struct v4l2_subdev_internal_ops v4l2_flash_subdev_internal_ops = {
647 	.open = v4l2_flash_open,
648 	.close = v4l2_flash_close,
649 };
650 
651 static const struct v4l2_subdev_ops v4l2_flash_subdev_ops;
652 
653 static struct v4l2_flash *__v4l2_flash_init(
654 	struct device *dev, struct fwnode_handle *fwn,
655 	struct led_classdev_flash *fled_cdev, struct led_classdev *iled_cdev,
656 	const struct v4l2_flash_ops *ops, struct v4l2_flash_config *config)
657 {
658 	struct v4l2_flash *v4l2_flash;
659 	struct v4l2_subdev *sd;
660 	int ret;
661 
662 	if (!config)
663 		return ERR_PTR(-EINVAL);
664 
665 	v4l2_flash = devm_kzalloc(dev, sizeof(*v4l2_flash), GFP_KERNEL);
666 	if (!v4l2_flash)
667 		return ERR_PTR(-ENOMEM);
668 
669 	sd = &v4l2_flash->sd;
670 	v4l2_flash->fled_cdev = fled_cdev;
671 	v4l2_flash->iled_cdev = iled_cdev;
672 	v4l2_flash->ops = ops;
673 	sd->dev = dev;
674 	sd->fwnode = fwn ? fwn : dev_fwnode(dev);
675 	v4l2_subdev_init(sd, &v4l2_flash_subdev_ops);
676 	sd->internal_ops = &v4l2_flash_subdev_internal_ops;
677 	sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
678 	strscpy(sd->name, config->dev_name, sizeof(sd->name));
679 
680 	ret = media_entity_pads_init(&sd->entity, 0, NULL);
681 	if (ret < 0)
682 		return ERR_PTR(ret);
683 
684 	sd->entity.function = MEDIA_ENT_F_FLASH;
685 
686 	ret = v4l2_flash_init_controls(v4l2_flash, config);
687 	if (ret < 0)
688 		goto err_init_controls;
689 
690 	fwnode_handle_get(sd->fwnode);
691 
692 	ret = v4l2_async_register_subdev(sd);
693 	if (ret < 0)
694 		goto err_async_register_sd;
695 
696 	return v4l2_flash;
697 
698 err_async_register_sd:
699 	fwnode_handle_put(sd->fwnode);
700 	v4l2_ctrl_handler_free(sd->ctrl_handler);
701 err_init_controls:
702 	media_entity_cleanup(&sd->entity);
703 
704 	return ERR_PTR(ret);
705 }
706 
707 struct v4l2_flash *v4l2_flash_init(
708 	struct device *dev, struct fwnode_handle *fwn,
709 	struct led_classdev_flash *fled_cdev,
710 	const struct v4l2_flash_ops *ops,
711 	struct v4l2_flash_config *config)
712 {
713 	return __v4l2_flash_init(dev, fwn, fled_cdev, NULL, ops, config);
714 }
715 EXPORT_SYMBOL_GPL(v4l2_flash_init);
716 
717 struct v4l2_flash *v4l2_flash_indicator_init(
718 	struct device *dev, struct fwnode_handle *fwn,
719 	struct led_classdev *iled_cdev,
720 	struct v4l2_flash_config *config)
721 {
722 	return __v4l2_flash_init(dev, fwn, NULL, iled_cdev, NULL, config);
723 }
724 EXPORT_SYMBOL_GPL(v4l2_flash_indicator_init);
725 
726 void v4l2_flash_release(struct v4l2_flash *v4l2_flash)
727 {
728 	struct v4l2_subdev *sd;
729 
730 	if (IS_ERR_OR_NULL(v4l2_flash))
731 		return;
732 
733 	sd = &v4l2_flash->sd;
734 
735 	v4l2_async_unregister_subdev(sd);
736 
737 	fwnode_handle_put(sd->fwnode);
738 
739 	v4l2_ctrl_handler_free(sd->ctrl_handler);
740 	media_entity_cleanup(&sd->entity);
741 }
742 EXPORT_SYMBOL_GPL(v4l2_flash_release);
743 
744 MODULE_AUTHOR("Jacek Anaszewski <j.anaszewski@samsung.com>");
745 MODULE_DESCRIPTION("V4L2 Flash sub-device helpers");
746 MODULE_LICENSE("GPL v2");
747