Commit | Line | Data |
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53e269c1 LP |
1 | /* |
2 | * Media entity | |
3 | * | |
4 | * Copyright (C) 2010 Nokia Corporation | |
5 | * | |
6 | * Contacts: Laurent Pinchart <laurent.pinchart@ideasonboard.com> | |
7 | * Sakari Ailus <sakari.ailus@iki.fi> | |
8 | * | |
9 | * This program is free software; you can redistribute it and/or modify | |
10 | * it under the terms of the GNU General Public License version 2 as | |
11 | * published by the Free Software Foundation. | |
12 | * | |
13 | * This program is distributed in the hope that it will be useful, | |
14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | * GNU General Public License for more details. | |
17 | * | |
18 | * You should have received a copy of the GNU General Public License | |
19 | * along with this program; if not, write to the Free Software | |
20 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
21 | */ | |
22 | ||
5c7b25b9 | 23 | #include <linux/bitmap.h> |
53e269c1 LP |
24 | #include <linux/module.h> |
25 | #include <linux/slab.h> | |
26 | #include <media/media-entity.h> | |
503c3d82 | 27 | #include <media/media-device.h> |
53e269c1 LP |
28 | |
29 | /** | |
30 | * media_entity_init - Initialize a media entity | |
31 | * | |
32 | * @num_pads: Total number of sink and source pads. | |
33 | * @extra_links: Initial estimate of the number of extra links. | |
34 | * @pads: Array of 'num_pads' pads. | |
35 | * | |
36 | * The total number of pads is an intrinsic property of entities known by the | |
37 | * entity driver, while the total number of links depends on hardware design | |
38 | * and is an extrinsic property unknown to the entity driver. However, in most | |
39 | * use cases the entity driver can guess the number of links which can safely | |
40 | * be assumed to be equal to or larger than the number of pads. | |
41 | * | |
42 | * For those reasons the links array can be preallocated based on the entity | |
43 | * driver guess and will be reallocated later if extra links need to be | |
44 | * created. | |
45 | * | |
46 | * This function allocates a links array with enough space to hold at least | |
47 | * 'num_pads' + 'extra_links' elements. The media_entity::max_links field will | |
48 | * be set to the number of allocated elements. | |
49 | * | |
50 | * The pads array is managed by the entity driver and passed to | |
51 | * media_entity_init() where its pointer will be stored in the entity structure. | |
52 | */ | |
53 | int | |
54 | media_entity_init(struct media_entity *entity, u16 num_pads, | |
55 | struct media_pad *pads, u16 extra_links) | |
56 | { | |
57 | struct media_link *links; | |
58 | unsigned int max_links = num_pads + extra_links; | |
59 | unsigned int i; | |
60 | ||
61 | links = kzalloc(max_links * sizeof(links[0]), GFP_KERNEL); | |
62 | if (links == NULL) | |
63 | return -ENOMEM; | |
64 | ||
65 | entity->group_id = 0; | |
66 | entity->max_links = max_links; | |
67 | entity->num_links = 0; | |
68 | entity->num_backlinks = 0; | |
69 | entity->num_pads = num_pads; | |
70 | entity->pads = pads; | |
71 | entity->links = links; | |
72 | ||
73 | for (i = 0; i < num_pads; i++) { | |
74 | pads[i].entity = entity; | |
75 | pads[i].index = i; | |
76 | } | |
77 | ||
78 | return 0; | |
79 | } | |
80 | EXPORT_SYMBOL_GPL(media_entity_init); | |
81 | ||
82 | void | |
83 | media_entity_cleanup(struct media_entity *entity) | |
84 | { | |
85 | kfree(entity->links); | |
86 | } | |
87 | EXPORT_SYMBOL_GPL(media_entity_cleanup); | |
88 | ||
a5ccc48a SA |
89 | /* ----------------------------------------------------------------------------- |
90 | * Graph traversal | |
91 | */ | |
92 | ||
93 | static struct media_entity * | |
94 | media_entity_other(struct media_entity *entity, struct media_link *link) | |
95 | { | |
96 | if (link->source->entity == entity) | |
97 | return link->sink->entity; | |
98 | else | |
99 | return link->source->entity; | |
100 | } | |
101 | ||
102 | /* push an entity to traversal stack */ | |
103 | static void stack_push(struct media_entity_graph *graph, | |
104 | struct media_entity *entity) | |
105 | { | |
106 | if (graph->top == MEDIA_ENTITY_ENUM_MAX_DEPTH - 1) { | |
107 | WARN_ON(1); | |
108 | return; | |
109 | } | |
110 | graph->top++; | |
111 | graph->stack[graph->top].link = 0; | |
112 | graph->stack[graph->top].entity = entity; | |
113 | } | |
114 | ||
115 | static struct media_entity *stack_pop(struct media_entity_graph *graph) | |
116 | { | |
117 | struct media_entity *entity; | |
118 | ||
119 | entity = graph->stack[graph->top].entity; | |
120 | graph->top--; | |
121 | ||
122 | return entity; | |
123 | } | |
124 | ||
a5ccc48a SA |
125 | #define link_top(en) ((en)->stack[(en)->top].link) |
126 | #define stack_top(en) ((en)->stack[(en)->top].entity) | |
127 | ||
128 | /** | |
129 | * media_entity_graph_walk_start - Start walking the media graph at a given entity | |
130 | * @graph: Media graph structure that will be used to walk the graph | |
131 | * @entity: Starting entity | |
132 | * | |
133 | * This function initializes the graph traversal structure to walk the entities | |
134 | * graph starting at the given entity. The traversal structure must not be | |
135 | * modified by the caller during graph traversal. When done the structure can | |
136 | * safely be freed. | |
137 | */ | |
138 | void media_entity_graph_walk_start(struct media_entity_graph *graph, | |
139 | struct media_entity *entity) | |
140 | { | |
141 | graph->top = 0; | |
142 | graph->stack[graph->top].entity = NULL; | |
5c7b25b9 LP |
143 | bitmap_zero(graph->entities, MEDIA_ENTITY_ENUM_MAX_ID); |
144 | ||
145 | if (WARN_ON(entity->id >= MEDIA_ENTITY_ENUM_MAX_ID)) | |
146 | return; | |
147 | ||
148 | __set_bit(entity->id, graph->entities); | |
a5ccc48a SA |
149 | stack_push(graph, entity); |
150 | } | |
151 | EXPORT_SYMBOL_GPL(media_entity_graph_walk_start); | |
152 | ||
153 | /** | |
154 | * media_entity_graph_walk_next - Get the next entity in the graph | |
155 | * @graph: Media graph structure | |
156 | * | |
157 | * Perform a depth-first traversal of the given media entities graph. | |
158 | * | |
159 | * The graph structure must have been previously initialized with a call to | |
160 | * media_entity_graph_walk_start(). | |
161 | * | |
162 | * Return the next entity in the graph or NULL if the whole graph have been | |
163 | * traversed. | |
164 | */ | |
165 | struct media_entity * | |
166 | media_entity_graph_walk_next(struct media_entity_graph *graph) | |
167 | { | |
168 | if (stack_top(graph) == NULL) | |
169 | return NULL; | |
170 | ||
171 | /* | |
172 | * Depth first search. Push entity to stack and continue from | |
173 | * top of the stack until no more entities on the level can be | |
174 | * found. | |
175 | */ | |
176 | while (link_top(graph) < stack_top(graph)->num_links) { | |
177 | struct media_entity *entity = stack_top(graph); | |
178 | struct media_link *link = &entity->links[link_top(graph)]; | |
179 | struct media_entity *next; | |
180 | ||
181 | /* The link is not enabled so we do not follow. */ | |
182 | if (!(link->flags & MEDIA_LNK_FL_ENABLED)) { | |
183 | link_top(graph)++; | |
184 | continue; | |
185 | } | |
186 | ||
187 | /* Get the entity in the other end of the link . */ | |
188 | next = media_entity_other(entity, link); | |
5c7b25b9 LP |
189 | if (WARN_ON(next->id >= MEDIA_ENTITY_ENUM_MAX_ID)) |
190 | return NULL; | |
a5ccc48a | 191 | |
5c7b25b9 LP |
192 | /* Has the entity already been visited? */ |
193 | if (__test_and_set_bit(next->id, graph->entities)) { | |
a5ccc48a SA |
194 | link_top(graph)++; |
195 | continue; | |
196 | } | |
197 | ||
198 | /* Push the new entity to stack and start over. */ | |
199 | link_top(graph)++; | |
200 | stack_push(graph, next); | |
201 | } | |
202 | ||
203 | return stack_pop(graph); | |
204 | } | |
205 | EXPORT_SYMBOL_GPL(media_entity_graph_walk_next); | |
206 | ||
e02188c9 LP |
207 | /* ----------------------------------------------------------------------------- |
208 | * Pipeline management | |
209 | */ | |
210 | ||
211 | /** | |
212 | * media_entity_pipeline_start - Mark a pipeline as streaming | |
213 | * @entity: Starting entity | |
214 | * @pipe: Media pipeline to be assigned to all entities in the pipeline. | |
215 | * | |
216 | * Mark all entities connected to a given entity through enabled links, either | |
217 | * directly or indirectly, as streaming. The given pipeline object is assigned to | |
218 | * every entity in the pipeline and stored in the media_entity pipe field. | |
219 | * | |
220 | * Calls to this function can be nested, in which case the same number of | |
221 | * media_entity_pipeline_stop() calls will be required to stop streaming. The | |
222 | * pipeline pointer must be identical for all nested calls to | |
223 | * media_entity_pipeline_start(). | |
224 | */ | |
af88be38 SA |
225 | __must_check int media_entity_pipeline_start(struct media_entity *entity, |
226 | struct media_pipeline *pipe) | |
e02188c9 LP |
227 | { |
228 | struct media_device *mdev = entity->parent; | |
229 | struct media_entity_graph graph; | |
af88be38 SA |
230 | struct media_entity *entity_err = entity; |
231 | int ret; | |
e02188c9 LP |
232 | |
233 | mutex_lock(&mdev->graph_mutex); | |
234 | ||
235 | media_entity_graph_walk_start(&graph, entity); | |
236 | ||
237 | while ((entity = media_entity_graph_walk_next(&graph))) { | |
ef69ee1b MCC |
238 | DECLARE_BITMAP(active, MEDIA_ENTITY_MAX_PADS); |
239 | DECLARE_BITMAP(has_no_links, MEDIA_ENTITY_MAX_PADS); | |
af88be38 SA |
240 | unsigned int i; |
241 | ||
e02188c9 LP |
242 | entity->stream_count++; |
243 | WARN_ON(entity->pipe && entity->pipe != pipe); | |
244 | entity->pipe = pipe; | |
af88be38 SA |
245 | |
246 | /* Already streaming --- no need to check. */ | |
247 | if (entity->stream_count > 1) | |
248 | continue; | |
249 | ||
250 | if (!entity->ops || !entity->ops->link_validate) | |
251 | continue; | |
252 | ||
de49c285 SA |
253 | bitmap_zero(active, entity->num_pads); |
254 | bitmap_fill(has_no_links, entity->num_pads); | |
255 | ||
af88be38 SA |
256 | for (i = 0; i < entity->num_links; i++) { |
257 | struct media_link *link = &entity->links[i]; | |
de49c285 SA |
258 | struct media_pad *pad = link->sink->entity == entity |
259 | ? link->sink : link->source; | |
260 | ||
261 | /* Mark that a pad is connected by a link. */ | |
262 | bitmap_clear(has_no_links, pad->index, 1); | |
263 | ||
264 | /* | |
265 | * Pads that either do not need to connect or | |
266 | * are connected through an enabled link are | |
267 | * fine. | |
268 | */ | |
269 | if (!(pad->flags & MEDIA_PAD_FL_MUST_CONNECT) || | |
270 | link->flags & MEDIA_LNK_FL_ENABLED) | |
271 | bitmap_set(active, pad->index, 1); | |
272 | ||
273 | /* | |
274 | * Link validation will only take place for | |
275 | * sink ends of the link that are enabled. | |
276 | */ | |
277 | if (link->sink != pad || | |
278 | !(link->flags & MEDIA_LNK_FL_ENABLED)) | |
af88be38 SA |
279 | continue; |
280 | ||
281 | ret = entity->ops->link_validate(link); | |
fab9d30b SA |
282 | if (ret < 0 && ret != -ENOIOCTLCMD) { |
283 | dev_dbg(entity->parent->dev, | |
284 | "link validation failed for \"%s\":%u -> \"%s\":%u, error %d\n", | |
823ea2a6 SA |
285 | link->source->entity->name, |
286 | link->source->index, | |
287 | entity->name, link->sink->index, ret); | |
af88be38 | 288 | goto error; |
fab9d30b | 289 | } |
af88be38 | 290 | } |
de49c285 SA |
291 | |
292 | /* Either no links or validated links are fine. */ | |
293 | bitmap_or(active, active, has_no_links, entity->num_pads); | |
294 | ||
295 | if (!bitmap_full(active, entity->num_pads)) { | |
296 | ret = -EPIPE; | |
fab9d30b SA |
297 | dev_dbg(entity->parent->dev, |
298 | "\"%s\":%u must be connected by an enabled link\n", | |
299 | entity->name, | |
094f1ca5 SA |
300 | (unsigned)find_first_zero_bit( |
301 | active, entity->num_pads)); | |
de49c285 SA |
302 | goto error; |
303 | } | |
e02188c9 LP |
304 | } |
305 | ||
306 | mutex_unlock(&mdev->graph_mutex); | |
af88be38 SA |
307 | |
308 | return 0; | |
309 | ||
310 | error: | |
311 | /* | |
312 | * Link validation on graph failed. We revert what we did and | |
313 | * return the error. | |
314 | */ | |
315 | media_entity_graph_walk_start(&graph, entity_err); | |
316 | ||
317 | while ((entity_err = media_entity_graph_walk_next(&graph))) { | |
318 | entity_err->stream_count--; | |
319 | if (entity_err->stream_count == 0) | |
320 | entity_err->pipe = NULL; | |
321 | ||
322 | /* | |
323 | * We haven't increased stream_count further than this | |
324 | * so we quit here. | |
325 | */ | |
326 | if (entity_err == entity) | |
327 | break; | |
328 | } | |
329 | ||
330 | mutex_unlock(&mdev->graph_mutex); | |
331 | ||
332 | return ret; | |
e02188c9 LP |
333 | } |
334 | EXPORT_SYMBOL_GPL(media_entity_pipeline_start); | |
335 | ||
336 | /** | |
337 | * media_entity_pipeline_stop - Mark a pipeline as not streaming | |
338 | * @entity: Starting entity | |
339 | * | |
340 | * Mark all entities connected to a given entity through enabled links, either | |
341 | * directly or indirectly, as not streaming. The media_entity pipe field is | |
342 | * reset to NULL. | |
343 | * | |
344 | * If multiple calls to media_entity_pipeline_start() have been made, the same | |
345 | * number of calls to this function are required to mark the pipeline as not | |
346 | * streaming. | |
347 | */ | |
348 | void media_entity_pipeline_stop(struct media_entity *entity) | |
349 | { | |
350 | struct media_device *mdev = entity->parent; | |
351 | struct media_entity_graph graph; | |
352 | ||
353 | mutex_lock(&mdev->graph_mutex); | |
354 | ||
355 | media_entity_graph_walk_start(&graph, entity); | |
356 | ||
357 | while ((entity = media_entity_graph_walk_next(&graph))) { | |
358 | entity->stream_count--; | |
359 | if (entity->stream_count == 0) | |
360 | entity->pipe = NULL; | |
361 | } | |
362 | ||
363 | mutex_unlock(&mdev->graph_mutex); | |
364 | } | |
365 | EXPORT_SYMBOL_GPL(media_entity_pipeline_stop); | |
366 | ||
503c3d82 LP |
367 | /* ----------------------------------------------------------------------------- |
368 | * Module use count | |
369 | */ | |
370 | ||
371 | /* | |
372 | * media_entity_get - Get a reference to the parent module | |
373 | * @entity: The entity | |
374 | * | |
375 | * Get a reference to the parent media device module. | |
376 | * | |
377 | * The function will return immediately if @entity is NULL. | |
378 | * | |
379 | * Return a pointer to the entity on success or NULL on failure. | |
380 | */ | |
381 | struct media_entity *media_entity_get(struct media_entity *entity) | |
382 | { | |
383 | if (entity == NULL) | |
384 | return NULL; | |
385 | ||
386 | if (entity->parent->dev && | |
387 | !try_module_get(entity->parent->dev->driver->owner)) | |
388 | return NULL; | |
389 | ||
390 | return entity; | |
391 | } | |
392 | EXPORT_SYMBOL_GPL(media_entity_get); | |
393 | ||
394 | /* | |
395 | * media_entity_put - Release the reference to the parent module | |
396 | * @entity: The entity | |
397 | * | |
398 | * Release the reference count acquired by media_entity_get(). | |
399 | * | |
400 | * The function will return immediately if @entity is NULL. | |
401 | */ | |
402 | void media_entity_put(struct media_entity *entity) | |
403 | { | |
404 | if (entity == NULL) | |
405 | return; | |
406 | ||
407 | if (entity->parent->dev) | |
408 | module_put(entity->parent->dev->driver->owner); | |
409 | } | |
410 | EXPORT_SYMBOL_GPL(media_entity_put); | |
411 | ||
a5ccc48a SA |
412 | /* ----------------------------------------------------------------------------- |
413 | * Links management | |
414 | */ | |
415 | ||
53e269c1 LP |
416 | static struct media_link *media_entity_add_link(struct media_entity *entity) |
417 | { | |
418 | if (entity->num_links >= entity->max_links) { | |
419 | struct media_link *links = entity->links; | |
420 | unsigned int max_links = entity->max_links + 2; | |
421 | unsigned int i; | |
422 | ||
423 | links = krealloc(links, max_links * sizeof(*links), GFP_KERNEL); | |
424 | if (links == NULL) | |
425 | return NULL; | |
426 | ||
427 | for (i = 0; i < entity->num_links; i++) | |
428 | links[i].reverse->reverse = &links[i]; | |
429 | ||
430 | entity->max_links = max_links; | |
431 | entity->links = links; | |
432 | } | |
433 | ||
434 | return &entity->links[entity->num_links++]; | |
435 | } | |
436 | ||
437 | int | |
438 | media_entity_create_link(struct media_entity *source, u16 source_pad, | |
439 | struct media_entity *sink, u16 sink_pad, u32 flags) | |
440 | { | |
441 | struct media_link *link; | |
442 | struct media_link *backlink; | |
443 | ||
444 | BUG_ON(source == NULL || sink == NULL); | |
445 | BUG_ON(source_pad >= source->num_pads); | |
446 | BUG_ON(sink_pad >= sink->num_pads); | |
447 | ||
448 | link = media_entity_add_link(source); | |
449 | if (link == NULL) | |
450 | return -ENOMEM; | |
451 | ||
452 | link->source = &source->pads[source_pad]; | |
453 | link->sink = &sink->pads[sink_pad]; | |
454 | link->flags = flags; | |
455 | ||
456 | /* Create the backlink. Backlinks are used to help graph traversal and | |
457 | * are not reported to userspace. | |
458 | */ | |
459 | backlink = media_entity_add_link(sink); | |
460 | if (backlink == NULL) { | |
461 | source->num_links--; | |
462 | return -ENOMEM; | |
463 | } | |
464 | ||
465 | backlink->source = &source->pads[source_pad]; | |
466 | backlink->sink = &sink->pads[sink_pad]; | |
467 | backlink->flags = flags; | |
468 | ||
469 | link->reverse = backlink; | |
470 | backlink->reverse = link; | |
471 | ||
472 | sink->num_backlinks++; | |
473 | ||
474 | return 0; | |
475 | } | |
476 | EXPORT_SYMBOL_GPL(media_entity_create_link); | |
97548ed4 | 477 | |
7349cec1 SN |
478 | void __media_entity_remove_links(struct media_entity *entity) |
479 | { | |
480 | unsigned int i; | |
481 | ||
482 | for (i = 0; i < entity->num_links; i++) { | |
483 | struct media_link *link = &entity->links[i]; | |
484 | struct media_entity *remote; | |
485 | unsigned int r = 0; | |
486 | ||
487 | if (link->source->entity == entity) | |
488 | remote = link->sink->entity; | |
489 | else | |
490 | remote = link->source->entity; | |
491 | ||
492 | while (r < remote->num_links) { | |
493 | struct media_link *rlink = &remote->links[r]; | |
494 | ||
495 | if (rlink != link->reverse) { | |
496 | r++; | |
497 | continue; | |
498 | } | |
499 | ||
500 | if (link->source->entity == entity) | |
501 | remote->num_backlinks--; | |
502 | ||
503 | if (--remote->num_links == 0) | |
504 | break; | |
505 | ||
506 | /* Insert last entry in place of the dropped link. */ | |
507 | *rlink = remote->links[remote->num_links]; | |
508 | } | |
509 | } | |
510 | ||
511 | entity->num_links = 0; | |
512 | entity->num_backlinks = 0; | |
513 | } | |
514 | EXPORT_SYMBOL_GPL(__media_entity_remove_links); | |
515 | ||
516 | void media_entity_remove_links(struct media_entity *entity) | |
517 | { | |
518 | /* Do nothing if the entity is not registered. */ | |
519 | if (entity->parent == NULL) | |
520 | return; | |
521 | ||
522 | mutex_lock(&entity->parent->graph_mutex); | |
523 | __media_entity_remove_links(entity); | |
524 | mutex_unlock(&entity->parent->graph_mutex); | |
525 | } | |
526 | EXPORT_SYMBOL_GPL(media_entity_remove_links); | |
527 | ||
97548ed4 LP |
528 | static int __media_entity_setup_link_notify(struct media_link *link, u32 flags) |
529 | { | |
97548ed4 LP |
530 | int ret; |
531 | ||
532 | /* Notify both entities. */ | |
533 | ret = media_entity_call(link->source->entity, link_setup, | |
534 | link->source, link->sink, flags); | |
535 | if (ret < 0 && ret != -ENOIOCTLCMD) | |
536 | return ret; | |
537 | ||
538 | ret = media_entity_call(link->sink->entity, link_setup, | |
539 | link->sink, link->source, flags); | |
540 | if (ret < 0 && ret != -ENOIOCTLCMD) { | |
541 | media_entity_call(link->source->entity, link_setup, | |
542 | link->source, link->sink, link->flags); | |
543 | return ret; | |
544 | } | |
545 | ||
7a6f0b22 | 546 | link->flags = flags; |
97548ed4 LP |
547 | link->reverse->flags = link->flags; |
548 | ||
549 | return 0; | |
550 | } | |
551 | ||
552 | /** | |
553 | * __media_entity_setup_link - Configure a media link | |
554 | * @link: The link being configured | |
555 | * @flags: Link configuration flags | |
556 | * | |
557 | * The bulk of link setup is handled by the two entities connected through the | |
558 | * link. This function notifies both entities of the link configuration change. | |
559 | * | |
560 | * If the link is immutable or if the current and new configuration are | |
561 | * identical, return immediately. | |
562 | * | |
563 | * The user is expected to hold link->source->parent->mutex. If not, | |
564 | * media_entity_setup_link() should be used instead. | |
565 | */ | |
566 | int __media_entity_setup_link(struct media_link *link, u32 flags) | |
567 | { | |
7a6f0b22 | 568 | const u32 mask = MEDIA_LNK_FL_ENABLED; |
97548ed4 LP |
569 | struct media_device *mdev; |
570 | struct media_entity *source, *sink; | |
571 | int ret = -EBUSY; | |
572 | ||
573 | if (link == NULL) | |
574 | return -EINVAL; | |
575 | ||
7a6f0b22 LP |
576 | /* The non-modifiable link flags must not be modified. */ |
577 | if ((link->flags & ~mask) != (flags & ~mask)) | |
578 | return -EINVAL; | |
579 | ||
97548ed4 LP |
580 | if (link->flags & MEDIA_LNK_FL_IMMUTABLE) |
581 | return link->flags == flags ? 0 : -EINVAL; | |
582 | ||
583 | if (link->flags == flags) | |
584 | return 0; | |
585 | ||
586 | source = link->source->entity; | |
587 | sink = link->sink->entity; | |
588 | ||
e02188c9 LP |
589 | if (!(link->flags & MEDIA_LNK_FL_DYNAMIC) && |
590 | (source->stream_count || sink->stream_count)) | |
591 | return -EBUSY; | |
592 | ||
97548ed4 LP |
593 | mdev = source->parent; |
594 | ||
813f5c0a SN |
595 | if (mdev->link_notify) { |
596 | ret = mdev->link_notify(link, flags, | |
597 | MEDIA_DEV_NOTIFY_PRE_LINK_CH); | |
97548ed4 LP |
598 | if (ret < 0) |
599 | return ret; | |
600 | } | |
601 | ||
602 | ret = __media_entity_setup_link_notify(link, flags); | |
97548ed4 | 603 | |
813f5c0a SN |
604 | if (mdev->link_notify) |
605 | mdev->link_notify(link, flags, MEDIA_DEV_NOTIFY_POST_LINK_CH); | |
97548ed4 LP |
606 | |
607 | return ret; | |
608 | } | |
609 | ||
610 | int media_entity_setup_link(struct media_link *link, u32 flags) | |
611 | { | |
612 | int ret; | |
613 | ||
614 | mutex_lock(&link->source->entity->parent->graph_mutex); | |
615 | ret = __media_entity_setup_link(link, flags); | |
616 | mutex_unlock(&link->source->entity->parent->graph_mutex); | |
617 | ||
618 | return ret; | |
619 | } | |
620 | EXPORT_SYMBOL_GPL(media_entity_setup_link); | |
621 | ||
622 | /** | |
623 | * media_entity_find_link - Find a link between two pads | |
624 | * @source: Source pad | |
625 | * @sink: Sink pad | |
626 | * | |
627 | * Return a pointer to the link between the two entities. If no such link | |
628 | * exists, return NULL. | |
629 | */ | |
630 | struct media_link * | |
631 | media_entity_find_link(struct media_pad *source, struct media_pad *sink) | |
632 | { | |
633 | struct media_link *link; | |
634 | unsigned int i; | |
635 | ||
636 | for (i = 0; i < source->entity->num_links; ++i) { | |
637 | link = &source->entity->links[i]; | |
638 | ||
639 | if (link->source->entity == source->entity && | |
640 | link->source->index == source->index && | |
641 | link->sink->entity == sink->entity && | |
642 | link->sink->index == sink->index) | |
643 | return link; | |
644 | } | |
645 | ||
646 | return NULL; | |
647 | } | |
648 | EXPORT_SYMBOL_GPL(media_entity_find_link); | |
649 | ||
650 | /** | |
1bddf1b3 AH |
651 | * media_entity_remote_pad - Find the pad at the remote end of a link |
652 | * @pad: Pad at the local end of the link | |
97548ed4 | 653 | * |
1bddf1b3 AH |
654 | * Search for a remote pad connected to the given pad by iterating over all |
655 | * links originating or terminating at that pad until an enabled link is found. | |
97548ed4 LP |
656 | * |
657 | * Return a pointer to the pad at the remote end of the first found enabled | |
658 | * link, or NULL if no enabled link has been found. | |
659 | */ | |
1bddf1b3 | 660 | struct media_pad *media_entity_remote_pad(struct media_pad *pad) |
97548ed4 LP |
661 | { |
662 | unsigned int i; | |
663 | ||
664 | for (i = 0; i < pad->entity->num_links; i++) { | |
665 | struct media_link *link = &pad->entity->links[i]; | |
666 | ||
667 | if (!(link->flags & MEDIA_LNK_FL_ENABLED)) | |
668 | continue; | |
669 | ||
670 | if (link->source == pad) | |
671 | return link->sink; | |
672 | ||
673 | if (link->sink == pad) | |
674 | return link->source; | |
675 | } | |
676 | ||
677 | return NULL; | |
678 | ||
679 | } | |
1bddf1b3 | 680 | EXPORT_SYMBOL_GPL(media_entity_remote_pad); |