xref: /linux/drivers/media/v4l2-core/v4l2-flash-led-class.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2  * V4L2 flash LED sub-device registration helpers.
3  *
4  *	Copyright (C) 2015 Samsung Electronics Co., Ltd
5  *	Author: Jacek Anaszewski <j.anaszewski@samsung.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 
12 #include <linux/led-class-flash.h>
13 #include <linux/module.h>
14 #include <linux/mutex.h>
15 #include <linux/of.h>
16 #include <linux/slab.h>
17 #include <linux/types.h>
18 #include <media/v4l2-flash-led-class.h>
19 
20 #define has_flash_op(v4l2_flash, op)				\
21 	(v4l2_flash && v4l2_flash->ops->op)
22 
23 #define call_flash_op(v4l2_flash, op, arg)			\
24 		(has_flash_op(v4l2_flash, op) ?			\
25 			v4l2_flash->ops->op(v4l2_flash, arg) :	\
26 			-EINVAL)
27 
28 enum ctrl_init_data_id {
29 	LED_MODE,
30 	TORCH_INTENSITY,
31 	FLASH_INTENSITY,
32 	INDICATOR_INTENSITY,
33 	FLASH_TIMEOUT,
34 	STROBE_SOURCE,
35 	/*
36 	 * Only above values are applicable to
37 	 * the 'ctrls' array in the struct v4l2_flash.
38 	 */
39 	FLASH_STROBE,
40 	STROBE_STOP,
41 	STROBE_STATUS,
42 	FLASH_FAULT,
43 	NUM_FLASH_CTRLS,
44 };
45 
46 static enum led_brightness __intensity_to_led_brightness(
47 					struct v4l2_ctrl *ctrl, s32 intensity)
48 {
49 	intensity -= ctrl->minimum;
50 	intensity /= (u32) ctrl->step;
51 
52 	/*
53 	 * Indicator LEDs, unlike torch LEDs, are turned on/off basing on
54 	 * the state of V4L2_CID_FLASH_INDICATOR_INTENSITY control only.
55 	 * Therefore it must be possible to set it to 0 level which in
56 	 * the LED subsystem reflects LED_OFF state.
57 	 */
58 	if (ctrl->minimum)
59 		++intensity;
60 
61 	return intensity;
62 }
63 
64 static s32 __led_brightness_to_intensity(struct v4l2_ctrl *ctrl,
65 					 enum led_brightness brightness)
66 {
67 	/*
68 	 * Indicator LEDs, unlike torch LEDs, are turned on/off basing on
69 	 * the state of V4L2_CID_FLASH_INDICATOR_INTENSITY control only.
70 	 * Do not decrement brightness read from the LED subsystem for
71 	 * indicator LED as it may equal 0. For torch LEDs this function
72 	 * is called only when V4L2_FLASH_LED_MODE_TORCH is set and the
73 	 * brightness read is guaranteed to be greater than 0. In the mode
74 	 * V4L2_FLASH_LED_MODE_NONE the cached torch intensity value is used.
75 	 */
76 	if (ctrl->id != V4L2_CID_FLASH_INDICATOR_INTENSITY)
77 		--brightness;
78 
79 	return (brightness * ctrl->step) + ctrl->minimum;
80 }
81 
82 static void v4l2_flash_set_led_brightness(struct v4l2_flash *v4l2_flash,
83 					struct v4l2_ctrl *ctrl)
84 {
85 	struct v4l2_ctrl **ctrls = v4l2_flash->ctrls;
86 	enum led_brightness brightness;
87 
88 	if (has_flash_op(v4l2_flash, intensity_to_led_brightness))
89 		brightness = call_flash_op(v4l2_flash,
90 					intensity_to_led_brightness,
91 					ctrl->val);
92 	else
93 		brightness = __intensity_to_led_brightness(ctrl, ctrl->val);
94 	/*
95 	 * In case a LED Flash class driver provides ops for custom
96 	 * brightness <-> intensity conversion, it also must have defined
97 	 * related v4l2 control step == 1. In such a case a backward conversion
98 	 * from led brightness to v4l2 intensity is required to find out the
99 	 * the aligned intensity value.
100 	 */
101 	if (has_flash_op(v4l2_flash, led_brightness_to_intensity))
102 		ctrl->val = call_flash_op(v4l2_flash,
103 					led_brightness_to_intensity,
104 					brightness);
105 
106 	if (ctrl == ctrls[TORCH_INTENSITY]) {
107 		if (ctrls[LED_MODE]->val != V4L2_FLASH_LED_MODE_TORCH)
108 			return;
109 
110 		led_set_brightness(&v4l2_flash->fled_cdev->led_cdev,
111 					brightness);
112 	} else {
113 		led_set_brightness(&v4l2_flash->iled_cdev->led_cdev,
114 					brightness);
115 	}
116 }
117 
118 static int v4l2_flash_update_led_brightness(struct v4l2_flash *v4l2_flash,
119 					struct v4l2_ctrl *ctrl)
120 {
121 	struct v4l2_ctrl **ctrls = v4l2_flash->ctrls;
122 	struct led_classdev *led_cdev;
123 	int ret;
124 
125 	if (ctrl == ctrls[TORCH_INTENSITY]) {
126 		/*
127 		 * Update torch brightness only if in TORCH_MODE. In other modes
128 		 * torch led is turned off, which would spuriously inform the
129 		 * user space that V4L2_CID_FLASH_TORCH_INTENSITY control value
130 		 * has changed to 0.
131 		 */
132 		if (ctrls[LED_MODE]->val != V4L2_FLASH_LED_MODE_TORCH)
133 			return 0;
134 		led_cdev = &v4l2_flash->fled_cdev->led_cdev;
135 	} else {
136 		led_cdev = &v4l2_flash->iled_cdev->led_cdev;
137 	}
138 
139 	ret = led_update_brightness(led_cdev);
140 	if (ret < 0)
141 		return ret;
142 
143 	if (has_flash_op(v4l2_flash, led_brightness_to_intensity))
144 		ctrl->val = call_flash_op(v4l2_flash,
145 						led_brightness_to_intensity,
146 						led_cdev->brightness);
147 	else
148 		ctrl->val = __led_brightness_to_intensity(ctrl,
149 						led_cdev->brightness);
150 
151 	return 0;
152 }
153 
154 static int v4l2_flash_g_volatile_ctrl(struct v4l2_ctrl *c)
155 {
156 	struct v4l2_flash *v4l2_flash = v4l2_ctrl_to_v4l2_flash(c);
157 	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
158 	bool is_strobing;
159 	int ret;
160 
161 	switch (c->id) {
162 	case V4L2_CID_FLASH_TORCH_INTENSITY:
163 	case V4L2_CID_FLASH_INDICATOR_INTENSITY:
164 		return v4l2_flash_update_led_brightness(v4l2_flash, c);
165 	case V4L2_CID_FLASH_INTENSITY:
166 		ret = led_update_flash_brightness(fled_cdev);
167 		if (ret < 0)
168 			return ret;
169 		/*
170 		 * No conversion is needed as LED Flash class also uses
171 		 * microamperes for flash intensity units.
172 		 */
173 		c->val = fled_cdev->brightness.val;
174 		return 0;
175 	case V4L2_CID_FLASH_STROBE_STATUS:
176 		ret = led_get_flash_strobe(fled_cdev, &is_strobing);
177 		if (ret < 0)
178 			return ret;
179 		c->val = is_strobing;
180 		return 0;
181 	case V4L2_CID_FLASH_FAULT:
182 		/* LED faults map directly to V4L2 flash faults */
183 		return led_get_flash_fault(fled_cdev, &c->val);
184 	default:
185 		return -EINVAL;
186 	}
187 }
188 
189 static bool __software_strobe_mode_inactive(struct v4l2_ctrl **ctrls)
190 {
191 	return ((ctrls[LED_MODE]->val != V4L2_FLASH_LED_MODE_FLASH) ||
192 		(ctrls[STROBE_SOURCE] && (ctrls[STROBE_SOURCE]->val !=
193 				V4L2_FLASH_STROBE_SOURCE_SOFTWARE)));
194 }
195 
196 static int v4l2_flash_s_ctrl(struct v4l2_ctrl *c)
197 {
198 	struct v4l2_flash *v4l2_flash = v4l2_ctrl_to_v4l2_flash(c);
199 	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
200 	struct led_classdev *led_cdev = &fled_cdev->led_cdev;
201 	struct v4l2_ctrl **ctrls = v4l2_flash->ctrls;
202 	bool external_strobe;
203 	int ret = 0;
204 
205 	switch (c->id) {
206 	case V4L2_CID_FLASH_LED_MODE:
207 		switch (c->val) {
208 		case V4L2_FLASH_LED_MODE_NONE:
209 			led_set_brightness(led_cdev, LED_OFF);
210 			return led_set_flash_strobe(fled_cdev, false);
211 		case V4L2_FLASH_LED_MODE_FLASH:
212 			/* Turn the torch LED off */
213 			led_set_brightness(led_cdev, LED_OFF);
214 			if (ctrls[STROBE_SOURCE]) {
215 				external_strobe = (ctrls[STROBE_SOURCE]->val ==
216 					V4L2_FLASH_STROBE_SOURCE_EXTERNAL);
217 
218 				ret = call_flash_op(v4l2_flash,
219 						external_strobe_set,
220 						external_strobe);
221 			}
222 			return ret;
223 		case V4L2_FLASH_LED_MODE_TORCH:
224 			if (ctrls[STROBE_SOURCE]) {
225 				ret = call_flash_op(v4l2_flash,
226 						external_strobe_set,
227 						false);
228 				if (ret < 0)
229 					return ret;
230 			}
231 			/* Stop flash strobing */
232 			ret = led_set_flash_strobe(fled_cdev, false);
233 			if (ret < 0)
234 				return ret;
235 
236 			v4l2_flash_set_led_brightness(v4l2_flash,
237 							ctrls[TORCH_INTENSITY]);
238 			return 0;
239 		}
240 		break;
241 	case V4L2_CID_FLASH_STROBE_SOURCE:
242 		external_strobe = (c->val == V4L2_FLASH_STROBE_SOURCE_EXTERNAL);
243 		/*
244 		 * For some hardware arrangements setting strobe source may
245 		 * affect torch mode. Therefore, if not in the flash mode,
246 		 * cache only this setting. It will be applied upon switching
247 		 * to flash mode.
248 		 */
249 		if (ctrls[LED_MODE]->val != V4L2_FLASH_LED_MODE_FLASH)
250 			return 0;
251 
252 		return call_flash_op(v4l2_flash, external_strobe_set,
253 					external_strobe);
254 	case V4L2_CID_FLASH_STROBE:
255 		if (__software_strobe_mode_inactive(ctrls))
256 			return -EBUSY;
257 		return led_set_flash_strobe(fled_cdev, true);
258 	case V4L2_CID_FLASH_STROBE_STOP:
259 		if (__software_strobe_mode_inactive(ctrls))
260 			return -EBUSY;
261 		return led_set_flash_strobe(fled_cdev, false);
262 	case V4L2_CID_FLASH_TIMEOUT:
263 		/*
264 		 * No conversion is needed as LED Flash class also uses
265 		 * microseconds for flash timeout units.
266 		 */
267 		return led_set_flash_timeout(fled_cdev, c->val);
268 	case V4L2_CID_FLASH_INTENSITY:
269 		/*
270 		 * No conversion is needed as LED Flash class also uses
271 		 * microamperes for flash intensity units.
272 		 */
273 		return led_set_flash_brightness(fled_cdev, c->val);
274 	case V4L2_CID_FLASH_TORCH_INTENSITY:
275 	case V4L2_CID_FLASH_INDICATOR_INTENSITY:
276 		v4l2_flash_set_led_brightness(v4l2_flash, c);
277 		return 0;
278 	}
279 
280 	return -EINVAL;
281 }
282 
283 static const struct v4l2_ctrl_ops v4l2_flash_ctrl_ops = {
284 	.g_volatile_ctrl = v4l2_flash_g_volatile_ctrl,
285 	.s_ctrl = v4l2_flash_s_ctrl,
286 };
287 
288 static void __lfs_to_v4l2_ctrl_config(struct led_flash_setting *s,
289 				struct v4l2_ctrl_config *c)
290 {
291 	c->min = s->min;
292 	c->max = s->max;
293 	c->step = s->step;
294 	c->def = s->val;
295 }
296 
297 static void __fill_ctrl_init_data(struct v4l2_flash *v4l2_flash,
298 			  struct v4l2_flash_config *flash_cfg,
299 			  struct v4l2_flash_ctrl_data *ctrl_init_data)
300 {
301 	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
302 	const struct led_flash_ops *fled_cdev_ops = fled_cdev->ops;
303 	struct led_classdev *led_cdev = &fled_cdev->led_cdev;
304 	struct v4l2_ctrl_config *ctrl_cfg;
305 	u32 mask;
306 
307 	/* Init FLASH_FAULT ctrl data */
308 	if (flash_cfg->flash_faults) {
309 		ctrl_init_data[FLASH_FAULT].cid = V4L2_CID_FLASH_FAULT;
310 		ctrl_cfg = &ctrl_init_data[FLASH_FAULT].config;
311 		ctrl_cfg->id = V4L2_CID_FLASH_FAULT;
312 		ctrl_cfg->max = flash_cfg->flash_faults;
313 		ctrl_cfg->flags = V4L2_CTRL_FLAG_VOLATILE |
314 				  V4L2_CTRL_FLAG_READ_ONLY;
315 	}
316 
317 	/* Init FLASH_LED_MODE ctrl data */
318 	mask = 1 << V4L2_FLASH_LED_MODE_NONE |
319 	       1 << V4L2_FLASH_LED_MODE_TORCH;
320 	if (led_cdev->flags & LED_DEV_CAP_FLASH)
321 		mask |= 1 << V4L2_FLASH_LED_MODE_FLASH;
322 
323 	ctrl_init_data[LED_MODE].cid = V4L2_CID_FLASH_LED_MODE;
324 	ctrl_cfg = &ctrl_init_data[LED_MODE].config;
325 	ctrl_cfg->id = V4L2_CID_FLASH_LED_MODE;
326 	ctrl_cfg->max = V4L2_FLASH_LED_MODE_TORCH;
327 	ctrl_cfg->menu_skip_mask = ~mask;
328 	ctrl_cfg->def = V4L2_FLASH_LED_MODE_NONE;
329 	ctrl_cfg->flags = 0;
330 
331 	/* Init TORCH_INTENSITY ctrl data */
332 	ctrl_init_data[TORCH_INTENSITY].cid = V4L2_CID_FLASH_TORCH_INTENSITY;
333 	ctrl_cfg = &ctrl_init_data[TORCH_INTENSITY].config;
334 	__lfs_to_v4l2_ctrl_config(&flash_cfg->torch_intensity, ctrl_cfg);
335 	ctrl_cfg->id = V4L2_CID_FLASH_TORCH_INTENSITY;
336 	ctrl_cfg->flags = V4L2_CTRL_FLAG_VOLATILE |
337 			  V4L2_CTRL_FLAG_EXECUTE_ON_WRITE;
338 
339 	/* Init INDICATOR_INTENSITY ctrl data */
340 	if (v4l2_flash->iled_cdev) {
341 		ctrl_init_data[INDICATOR_INTENSITY].cid =
342 					V4L2_CID_FLASH_INDICATOR_INTENSITY;
343 		ctrl_cfg = &ctrl_init_data[INDICATOR_INTENSITY].config;
344 		__lfs_to_v4l2_ctrl_config(&flash_cfg->indicator_intensity,
345 					  ctrl_cfg);
346 		ctrl_cfg->id = V4L2_CID_FLASH_INDICATOR_INTENSITY;
347 		ctrl_cfg->min = 0;
348 		ctrl_cfg->flags = V4L2_CTRL_FLAG_VOLATILE |
349 				  V4L2_CTRL_FLAG_EXECUTE_ON_WRITE;
350 	}
351 
352 	if (!(led_cdev->flags & LED_DEV_CAP_FLASH))
353 		return;
354 
355 	/* Init FLASH_STROBE ctrl data */
356 	ctrl_init_data[FLASH_STROBE].cid = V4L2_CID_FLASH_STROBE;
357 	ctrl_cfg = &ctrl_init_data[FLASH_STROBE].config;
358 	ctrl_cfg->id = V4L2_CID_FLASH_STROBE;
359 
360 	/* Init STROBE_STOP ctrl data */
361 	ctrl_init_data[STROBE_STOP].cid = V4L2_CID_FLASH_STROBE_STOP;
362 	ctrl_cfg = &ctrl_init_data[STROBE_STOP].config;
363 	ctrl_cfg->id = V4L2_CID_FLASH_STROBE_STOP;
364 
365 	/* Init FLASH_STROBE_SOURCE ctrl data */
366 	if (flash_cfg->has_external_strobe) {
367 		mask = (1 << V4L2_FLASH_STROBE_SOURCE_SOFTWARE) |
368 		       (1 << V4L2_FLASH_STROBE_SOURCE_EXTERNAL);
369 		ctrl_init_data[STROBE_SOURCE].cid =
370 					V4L2_CID_FLASH_STROBE_SOURCE;
371 		ctrl_cfg = &ctrl_init_data[STROBE_SOURCE].config;
372 		ctrl_cfg->id = V4L2_CID_FLASH_STROBE_SOURCE;
373 		ctrl_cfg->max = V4L2_FLASH_STROBE_SOURCE_EXTERNAL;
374 		ctrl_cfg->menu_skip_mask = ~mask;
375 		ctrl_cfg->def = V4L2_FLASH_STROBE_SOURCE_SOFTWARE;
376 	}
377 
378 	/* Init STROBE_STATUS ctrl data */
379 	if (fled_cdev_ops->strobe_get) {
380 		ctrl_init_data[STROBE_STATUS].cid =
381 					V4L2_CID_FLASH_STROBE_STATUS;
382 		ctrl_cfg = &ctrl_init_data[STROBE_STATUS].config;
383 		ctrl_cfg->id = V4L2_CID_FLASH_STROBE_STATUS;
384 		ctrl_cfg->flags = V4L2_CTRL_FLAG_VOLATILE |
385 				  V4L2_CTRL_FLAG_READ_ONLY;
386 	}
387 
388 	/* Init FLASH_TIMEOUT ctrl data */
389 	if (fled_cdev_ops->timeout_set) {
390 		ctrl_init_data[FLASH_TIMEOUT].cid = V4L2_CID_FLASH_TIMEOUT;
391 		ctrl_cfg = &ctrl_init_data[FLASH_TIMEOUT].config;
392 		__lfs_to_v4l2_ctrl_config(&fled_cdev->timeout, ctrl_cfg);
393 		ctrl_cfg->id = V4L2_CID_FLASH_TIMEOUT;
394 	}
395 
396 	/* Init FLASH_INTENSITY ctrl data */
397 	if (fled_cdev_ops->flash_brightness_set) {
398 		ctrl_init_data[FLASH_INTENSITY].cid = V4L2_CID_FLASH_INTENSITY;
399 		ctrl_cfg = &ctrl_init_data[FLASH_INTENSITY].config;
400 		__lfs_to_v4l2_ctrl_config(&fled_cdev->brightness, ctrl_cfg);
401 		ctrl_cfg->id = V4L2_CID_FLASH_INTENSITY;
402 		ctrl_cfg->flags = V4L2_CTRL_FLAG_VOLATILE |
403 				  V4L2_CTRL_FLAG_EXECUTE_ON_WRITE;
404 	}
405 }
406 
407 static int v4l2_flash_init_controls(struct v4l2_flash *v4l2_flash,
408 				struct v4l2_flash_config *flash_cfg)
409 
410 {
411 	struct v4l2_flash_ctrl_data *ctrl_init_data;
412 	struct v4l2_ctrl *ctrl;
413 	struct v4l2_ctrl_config *ctrl_cfg;
414 	int i, ret, num_ctrls = 0;
415 
416 	v4l2_flash->ctrls = devm_kzalloc(v4l2_flash->sd.dev,
417 					sizeof(*v4l2_flash->ctrls) *
418 					(STROBE_SOURCE + 1), GFP_KERNEL);
419 	if (!v4l2_flash->ctrls)
420 		return -ENOMEM;
421 
422 	/* allocate memory dynamically so as not to exceed stack frame size */
423 	ctrl_init_data = kcalloc(NUM_FLASH_CTRLS, sizeof(*ctrl_init_data),
424 					GFP_KERNEL);
425 	if (!ctrl_init_data)
426 		return -ENOMEM;
427 
428 	__fill_ctrl_init_data(v4l2_flash, flash_cfg, ctrl_init_data);
429 
430 	for (i = 0; i < NUM_FLASH_CTRLS; ++i)
431 		if (ctrl_init_data[i].cid)
432 			++num_ctrls;
433 
434 	v4l2_ctrl_handler_init(&v4l2_flash->hdl, num_ctrls);
435 
436 	for (i = 0; i < NUM_FLASH_CTRLS; ++i) {
437 		ctrl_cfg = &ctrl_init_data[i].config;
438 		if (!ctrl_init_data[i].cid)
439 			continue;
440 
441 		if (ctrl_cfg->id == V4L2_CID_FLASH_LED_MODE ||
442 		    ctrl_cfg->id == V4L2_CID_FLASH_STROBE_SOURCE)
443 			ctrl = v4l2_ctrl_new_std_menu(&v4l2_flash->hdl,
444 						&v4l2_flash_ctrl_ops,
445 						ctrl_cfg->id,
446 						ctrl_cfg->max,
447 						ctrl_cfg->menu_skip_mask,
448 						ctrl_cfg->def);
449 		else
450 			ctrl = v4l2_ctrl_new_std(&v4l2_flash->hdl,
451 						&v4l2_flash_ctrl_ops,
452 						ctrl_cfg->id,
453 						ctrl_cfg->min,
454 						ctrl_cfg->max,
455 						ctrl_cfg->step,
456 						ctrl_cfg->def);
457 
458 		if (ctrl)
459 			ctrl->flags |= ctrl_cfg->flags;
460 
461 		if (i <= STROBE_SOURCE)
462 			v4l2_flash->ctrls[i] = ctrl;
463 	}
464 
465 	kfree(ctrl_init_data);
466 
467 	if (v4l2_flash->hdl.error) {
468 		ret = v4l2_flash->hdl.error;
469 		goto error_free_handler;
470 	}
471 
472 	v4l2_ctrl_handler_setup(&v4l2_flash->hdl);
473 
474 	v4l2_flash->sd.ctrl_handler = &v4l2_flash->hdl;
475 
476 	return 0;
477 
478 error_free_handler:
479 	v4l2_ctrl_handler_free(&v4l2_flash->hdl);
480 	return ret;
481 }
482 
483 static int __sync_device_with_v4l2_controls(struct v4l2_flash *v4l2_flash)
484 {
485 	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
486 	struct v4l2_ctrl **ctrls = v4l2_flash->ctrls;
487 	int ret = 0;
488 
489 	v4l2_flash_set_led_brightness(v4l2_flash, ctrls[TORCH_INTENSITY]);
490 
491 	if (ctrls[INDICATOR_INTENSITY])
492 		v4l2_flash_set_led_brightness(v4l2_flash,
493 						ctrls[INDICATOR_INTENSITY]);
494 
495 	if (ctrls[FLASH_TIMEOUT]) {
496 		ret = led_set_flash_timeout(fled_cdev,
497 					ctrls[FLASH_TIMEOUT]->val);
498 		if (ret < 0)
499 			return ret;
500 	}
501 
502 	if (ctrls[FLASH_INTENSITY]) {
503 		ret = led_set_flash_brightness(fled_cdev,
504 					ctrls[FLASH_INTENSITY]->val);
505 		if (ret < 0)
506 			return ret;
507 	}
508 
509 	/*
510 	 * For some hardware arrangements setting strobe source may affect
511 	 * torch mode. Synchronize strobe source setting only if not in torch
512 	 * mode. For torch mode case it will get synchronized upon switching
513 	 * to flash mode.
514 	 */
515 	if (ctrls[STROBE_SOURCE] &&
516 	    ctrls[LED_MODE]->val != V4L2_FLASH_LED_MODE_TORCH)
517 		ret = call_flash_op(v4l2_flash, external_strobe_set,
518 					ctrls[STROBE_SOURCE]->val);
519 
520 	return ret;
521 }
522 
523 /*
524  * V4L2 subdev internal operations
525  */
526 
527 static int v4l2_flash_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
528 {
529 	struct v4l2_flash *v4l2_flash = v4l2_subdev_to_v4l2_flash(sd);
530 	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
531 	struct led_classdev *led_cdev = &fled_cdev->led_cdev;
532 	struct led_classdev_flash *iled_cdev = v4l2_flash->iled_cdev;
533 	struct led_classdev *led_cdev_ind = NULL;
534 	int ret = 0;
535 
536 	if (!v4l2_fh_is_singular(&fh->vfh))
537 		return 0;
538 
539 	mutex_lock(&led_cdev->led_access);
540 
541 	led_sysfs_disable(led_cdev);
542 	led_trigger_remove(led_cdev);
543 
544 	mutex_unlock(&led_cdev->led_access);
545 
546 	if (iled_cdev) {
547 		led_cdev_ind = &iled_cdev->led_cdev;
548 
549 		mutex_lock(&led_cdev_ind->led_access);
550 
551 		led_sysfs_disable(led_cdev_ind);
552 		led_trigger_remove(led_cdev_ind);
553 
554 		mutex_unlock(&led_cdev_ind->led_access);
555 	}
556 
557 	ret = __sync_device_with_v4l2_controls(v4l2_flash);
558 	if (ret < 0)
559 		goto out_sync_device;
560 
561 	return 0;
562 out_sync_device:
563 	mutex_lock(&led_cdev->led_access);
564 	led_sysfs_enable(led_cdev);
565 	mutex_unlock(&led_cdev->led_access);
566 
567 	if (led_cdev_ind) {
568 		mutex_lock(&led_cdev_ind->led_access);
569 		led_sysfs_enable(led_cdev_ind);
570 		mutex_unlock(&led_cdev_ind->led_access);
571 	}
572 
573 	return ret;
574 }
575 
576 static int v4l2_flash_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
577 {
578 	struct v4l2_flash *v4l2_flash = v4l2_subdev_to_v4l2_flash(sd);
579 	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
580 	struct led_classdev *led_cdev = &fled_cdev->led_cdev;
581 	struct led_classdev_flash *iled_cdev = v4l2_flash->iled_cdev;
582 	int ret = 0;
583 
584 	if (!v4l2_fh_is_singular(&fh->vfh))
585 		return 0;
586 
587 	mutex_lock(&led_cdev->led_access);
588 
589 	if (v4l2_flash->ctrls[STROBE_SOURCE])
590 		ret = v4l2_ctrl_s_ctrl(v4l2_flash->ctrls[STROBE_SOURCE],
591 				V4L2_FLASH_STROBE_SOURCE_SOFTWARE);
592 	led_sysfs_enable(led_cdev);
593 
594 	mutex_unlock(&led_cdev->led_access);
595 
596 	if (iled_cdev) {
597 		struct led_classdev *led_cdev_ind = &iled_cdev->led_cdev;
598 
599 		mutex_lock(&led_cdev_ind->led_access);
600 		led_sysfs_enable(led_cdev_ind);
601 		mutex_unlock(&led_cdev_ind->led_access);
602 	}
603 
604 	return ret;
605 }
606 
607 static const struct v4l2_subdev_internal_ops v4l2_flash_subdev_internal_ops = {
608 	.open = v4l2_flash_open,
609 	.close = v4l2_flash_close,
610 };
611 
612 static const struct v4l2_subdev_core_ops v4l2_flash_core_ops = {
613 	.queryctrl = v4l2_subdev_queryctrl,
614 	.querymenu = v4l2_subdev_querymenu,
615 };
616 
617 static const struct v4l2_subdev_ops v4l2_flash_subdev_ops = {
618 	.core = &v4l2_flash_core_ops,
619 };
620 
621 struct v4l2_flash *v4l2_flash_init(
622 	struct device *dev, struct device_node *of_node,
623 	struct led_classdev_flash *fled_cdev,
624 	struct led_classdev_flash *iled_cdev,
625 	const struct v4l2_flash_ops *ops,
626 	struct v4l2_flash_config *config)
627 {
628 	struct v4l2_flash *v4l2_flash;
629 	struct led_classdev *led_cdev;
630 	struct v4l2_subdev *sd;
631 	int ret;
632 
633 	if (!fled_cdev || !ops || !config)
634 		return ERR_PTR(-EINVAL);
635 
636 	led_cdev = &fled_cdev->led_cdev;
637 
638 	v4l2_flash = devm_kzalloc(led_cdev->dev, sizeof(*v4l2_flash),
639 					GFP_KERNEL);
640 	if (!v4l2_flash)
641 		return ERR_PTR(-ENOMEM);
642 
643 	sd = &v4l2_flash->sd;
644 	v4l2_flash->fled_cdev = fled_cdev;
645 	v4l2_flash->iled_cdev = iled_cdev;
646 	v4l2_flash->ops = ops;
647 	sd->dev = dev;
648 	sd->of_node = of_node;
649 	v4l2_subdev_init(sd, &v4l2_flash_subdev_ops);
650 	sd->internal_ops = &v4l2_flash_subdev_internal_ops;
651 	sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
652 	strlcpy(sd->name, config->dev_name, sizeof(sd->name));
653 
654 	ret = media_entity_init(&sd->entity, 0, NULL, 0);
655 	if (ret < 0)
656 		return ERR_PTR(ret);
657 
658 	sd->entity.type = MEDIA_ENT_T_V4L2_SUBDEV_FLASH;
659 
660 	ret = v4l2_flash_init_controls(v4l2_flash, config);
661 	if (ret < 0)
662 		goto err_init_controls;
663 
664 	if (sd->of_node)
665 		of_node_get(sd->of_node);
666 	else
667 		of_node_get(led_cdev->dev->of_node);
668 
669 	ret = v4l2_async_register_subdev(sd);
670 	if (ret < 0)
671 		goto err_async_register_sd;
672 
673 	return v4l2_flash;
674 
675 err_async_register_sd:
676 	of_node_put(led_cdev->dev->of_node);
677 	v4l2_ctrl_handler_free(sd->ctrl_handler);
678 err_init_controls:
679 	media_entity_cleanup(&sd->entity);
680 
681 	return ERR_PTR(ret);
682 }
683 EXPORT_SYMBOL_GPL(v4l2_flash_init);
684 
685 void v4l2_flash_release(struct v4l2_flash *v4l2_flash)
686 {
687 	struct v4l2_subdev *sd;
688 	struct led_classdev *led_cdev;
689 
690 	if (IS_ERR_OR_NULL(v4l2_flash))
691 		return;
692 
693 	sd = &v4l2_flash->sd;
694 	led_cdev = &v4l2_flash->fled_cdev->led_cdev;
695 
696 	v4l2_async_unregister_subdev(sd);
697 
698 	if (sd->of_node)
699 		of_node_put(sd->of_node);
700 	else
701 		of_node_put(led_cdev->dev->of_node);
702 
703 	v4l2_ctrl_handler_free(sd->ctrl_handler);
704 	media_entity_cleanup(&sd->entity);
705 }
706 EXPORT_SYMBOL_GPL(v4l2_flash_release);
707 
708 MODULE_AUTHOR("Jacek Anaszewski <j.anaszewski@samsung.com>");
709 MODULE_DESCRIPTION("V4L2 Flash sub-device helpers");
710 MODULE_LICENSE("GPL v2");
711