Merge tag 'trace-printf-v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/trace...
[drm/drm-misc.git] / drivers / media / mc / mc-entity.c
blob045590905582054c46656e20463271b1f93fa6b4
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Media entity
5 * Copyright (C) 2010 Nokia Corporation
7 * Contacts: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
8 * Sakari Ailus <sakari.ailus@iki.fi>
9 */
11 #include <linux/bitmap.h>
12 #include <linux/list.h>
13 #include <linux/property.h>
14 #include <linux/slab.h>
15 #include <media/media-entity.h>
16 #include <media/media-device.h>
18 static inline const char *intf_type(struct media_interface *intf)
20 switch (intf->type) {
21 case MEDIA_INTF_T_DVB_FE:
22 return "dvb-frontend";
23 case MEDIA_INTF_T_DVB_DEMUX:
24 return "dvb-demux";
25 case MEDIA_INTF_T_DVB_DVR:
26 return "dvb-dvr";
27 case MEDIA_INTF_T_DVB_CA:
28 return "dvb-ca";
29 case MEDIA_INTF_T_DVB_NET:
30 return "dvb-net";
31 case MEDIA_INTF_T_V4L_VIDEO:
32 return "v4l-video";
33 case MEDIA_INTF_T_V4L_VBI:
34 return "v4l-vbi";
35 case MEDIA_INTF_T_V4L_RADIO:
36 return "v4l-radio";
37 case MEDIA_INTF_T_V4L_SUBDEV:
38 return "v4l-subdev";
39 case MEDIA_INTF_T_V4L_SWRADIO:
40 return "v4l-swradio";
41 case MEDIA_INTF_T_V4L_TOUCH:
42 return "v4l-touch";
43 default:
44 return "unknown-intf";
48 static inline const char *link_type_name(struct media_link *link)
50 switch (link->flags & MEDIA_LNK_FL_LINK_TYPE) {
51 case MEDIA_LNK_FL_DATA_LINK:
52 return "data";
53 case MEDIA_LNK_FL_INTERFACE_LINK:
54 return "interface";
55 case MEDIA_LNK_FL_ANCILLARY_LINK:
56 return "ancillary";
57 default:
58 return "unknown";
62 __must_check int media_entity_enum_init(struct media_entity_enum *ent_enum,
63 struct media_device *mdev)
65 int idx_max;
67 idx_max = ALIGN(mdev->entity_internal_idx_max + 1, BITS_PER_LONG);
68 ent_enum->bmap = bitmap_zalloc(idx_max, GFP_KERNEL);
69 if (!ent_enum->bmap)
70 return -ENOMEM;
72 ent_enum->idx_max = idx_max;
74 return 0;
76 EXPORT_SYMBOL_GPL(media_entity_enum_init);
78 void media_entity_enum_cleanup(struct media_entity_enum *ent_enum)
80 bitmap_free(ent_enum->bmap);
82 EXPORT_SYMBOL_GPL(media_entity_enum_cleanup);
84 /**
85 * dev_dbg_obj - Prints in debug mode a change on some object
87 * @event_name: Name of the event to report. Could be __func__
88 * @gobj: Pointer to the object
90 * Enabled only if DEBUG or CONFIG_DYNAMIC_DEBUG. Otherwise, it
91 * won't produce any code.
93 static void dev_dbg_obj(const char *event_name, struct media_gobj *gobj)
95 #if defined(DEBUG) || defined (CONFIG_DYNAMIC_DEBUG)
96 switch (media_type(gobj)) {
97 case MEDIA_GRAPH_ENTITY:
98 dev_dbg(gobj->mdev->dev,
99 "%s id %u: entity '%s'\n",
100 event_name, media_id(gobj),
101 gobj_to_entity(gobj)->name);
102 break;
103 case MEDIA_GRAPH_LINK:
105 struct media_link *link = gobj_to_link(gobj);
107 dev_dbg(gobj->mdev->dev,
108 "%s id %u: %s link id %u ==> id %u\n",
109 event_name, media_id(gobj), link_type_name(link),
110 media_id(link->gobj0),
111 media_id(link->gobj1));
112 break;
114 case MEDIA_GRAPH_PAD:
116 struct media_pad *pad = gobj_to_pad(gobj);
118 dev_dbg(gobj->mdev->dev,
119 "%s id %u: %s%spad '%s':%d\n",
120 event_name, media_id(gobj),
121 pad->flags & MEDIA_PAD_FL_SINK ? "sink " : "",
122 pad->flags & MEDIA_PAD_FL_SOURCE ? "source " : "",
123 pad->entity->name, pad->index);
124 break;
126 case MEDIA_GRAPH_INTF_DEVNODE:
128 struct media_interface *intf = gobj_to_intf(gobj);
129 struct media_intf_devnode *devnode = intf_to_devnode(intf);
131 dev_dbg(gobj->mdev->dev,
132 "%s id %u: intf_devnode %s - major: %d, minor: %d\n",
133 event_name, media_id(gobj),
134 intf_type(intf),
135 devnode->major, devnode->minor);
136 break;
139 #endif
142 void media_gobj_create(struct media_device *mdev,
143 enum media_gobj_type type,
144 struct media_gobj *gobj)
146 BUG_ON(!mdev);
148 gobj->mdev = mdev;
150 /* Create a per-type unique object ID */
151 gobj->id = media_gobj_gen_id(type, ++mdev->id);
153 switch (type) {
154 case MEDIA_GRAPH_ENTITY:
155 list_add_tail(&gobj->list, &mdev->entities);
156 break;
157 case MEDIA_GRAPH_PAD:
158 list_add_tail(&gobj->list, &mdev->pads);
159 break;
160 case MEDIA_GRAPH_LINK:
161 list_add_tail(&gobj->list, &mdev->links);
162 break;
163 case MEDIA_GRAPH_INTF_DEVNODE:
164 list_add_tail(&gobj->list, &mdev->interfaces);
165 break;
168 mdev->topology_version++;
170 dev_dbg_obj(__func__, gobj);
173 void media_gobj_destroy(struct media_gobj *gobj)
175 /* Do nothing if the object is not linked. */
176 if (gobj->mdev == NULL)
177 return;
179 dev_dbg_obj(__func__, gobj);
181 gobj->mdev->topology_version++;
183 /* Remove the object from mdev list */
184 list_del(&gobj->list);
186 gobj->mdev = NULL;
190 * TODO: Get rid of this.
192 #define MEDIA_ENTITY_MAX_PADS 512
194 int media_entity_pads_init(struct media_entity *entity, u16 num_pads,
195 struct media_pad *pads)
197 struct media_device *mdev = entity->graph_obj.mdev;
198 struct media_pad *iter;
199 unsigned int i = 0;
200 int ret = 0;
202 if (num_pads >= MEDIA_ENTITY_MAX_PADS)
203 return -E2BIG;
205 entity->num_pads = num_pads;
206 entity->pads = pads;
208 if (mdev)
209 mutex_lock(&mdev->graph_mutex);
211 media_entity_for_each_pad(entity, iter) {
212 iter->entity = entity;
213 iter->index = i++;
215 if (hweight32(iter->flags & (MEDIA_PAD_FL_SINK |
216 MEDIA_PAD_FL_SOURCE)) != 1) {
217 ret = -EINVAL;
218 break;
221 if (mdev)
222 media_gobj_create(mdev, MEDIA_GRAPH_PAD,
223 &iter->graph_obj);
226 if (ret && mdev) {
227 media_entity_for_each_pad(entity, iter)
228 media_gobj_destroy(&iter->graph_obj);
231 if (mdev)
232 mutex_unlock(&mdev->graph_mutex);
234 return ret;
236 EXPORT_SYMBOL_GPL(media_entity_pads_init);
238 /* -----------------------------------------------------------------------------
239 * Graph traversal
243 * media_entity_has_pad_interdep - Check interdependency between two pads
245 * @entity: The entity
246 * @pad0: The first pad index
247 * @pad1: The second pad index
249 * This function checks the interdependency inside the entity between @pad0
250 * and @pad1. If two pads are interdependent they are part of the same pipeline
251 * and enabling one of the pads means that the other pad will become "locked"
252 * and doesn't allow configuration changes.
254 * This function uses the &media_entity_operations.has_pad_interdep() operation
255 * to check the dependency inside the entity between @pad0 and @pad1. If the
256 * has_pad_interdep operation is not implemented, all pads of the entity are
257 * considered to be interdependent.
259 * One of @pad0 and @pad1 must be a sink pad and the other one a source pad.
260 * The function returns false if both pads are sinks or sources.
262 * The caller must hold entity->graph_obj.mdev->mutex.
264 * Return: true if the pads are connected internally and false otherwise.
266 static bool media_entity_has_pad_interdep(struct media_entity *entity,
267 unsigned int pad0, unsigned int pad1)
269 if (pad0 >= entity->num_pads || pad1 >= entity->num_pads)
270 return false;
272 if (entity->pads[pad0].flags & entity->pads[pad1].flags &
273 (MEDIA_PAD_FL_SINK | MEDIA_PAD_FL_SOURCE))
274 return false;
276 if (!entity->ops || !entity->ops->has_pad_interdep)
277 return true;
279 return entity->ops->has_pad_interdep(entity, pad0, pad1);
282 static struct media_entity *
283 media_entity_other(struct media_entity *entity, struct media_link *link)
285 if (link->source->entity == entity)
286 return link->sink->entity;
287 else
288 return link->source->entity;
291 /* push an entity to traversal stack */
292 static void stack_push(struct media_graph *graph,
293 struct media_entity *entity)
295 if (graph->top == MEDIA_ENTITY_ENUM_MAX_DEPTH - 1) {
296 WARN_ON(1);
297 return;
299 graph->top++;
300 graph->stack[graph->top].link = entity->links.next;
301 graph->stack[graph->top].entity = entity;
304 static struct media_entity *stack_pop(struct media_graph *graph)
306 struct media_entity *entity;
308 entity = graph->stack[graph->top].entity;
309 graph->top--;
311 return entity;
314 #define link_top(en) ((en)->stack[(en)->top].link)
315 #define stack_top(en) ((en)->stack[(en)->top].entity)
318 * media_graph_walk_init - Allocate resources for graph walk
319 * @graph: Media graph structure that will be used to walk the graph
320 * @mdev: Media device
322 * Reserve resources for graph walk in media device's current
323 * state. The memory must be released using
324 * media_graph_walk_cleanup().
326 * Returns error on failure, zero on success.
328 __must_check int media_graph_walk_init(
329 struct media_graph *graph, struct media_device *mdev)
331 return media_entity_enum_init(&graph->ent_enum, mdev);
333 EXPORT_SYMBOL_GPL(media_graph_walk_init);
336 * media_graph_walk_cleanup - Release resources related to graph walking
337 * @graph: Media graph structure that was used to walk the graph
339 void media_graph_walk_cleanup(struct media_graph *graph)
341 media_entity_enum_cleanup(&graph->ent_enum);
343 EXPORT_SYMBOL_GPL(media_graph_walk_cleanup);
345 void media_graph_walk_start(struct media_graph *graph,
346 struct media_entity *entity)
348 media_entity_enum_zero(&graph->ent_enum);
349 media_entity_enum_set(&graph->ent_enum, entity);
351 graph->top = 0;
352 graph->stack[graph->top].entity = NULL;
353 stack_push(graph, entity);
354 dev_dbg(entity->graph_obj.mdev->dev,
355 "begin graph walk at '%s'\n", entity->name);
357 EXPORT_SYMBOL_GPL(media_graph_walk_start);
359 static void media_graph_walk_iter(struct media_graph *graph)
361 struct media_entity *entity = stack_top(graph);
362 struct media_link *link;
363 struct media_entity *next;
365 link = list_entry(link_top(graph), typeof(*link), list);
367 /* If the link is not a data link, don't follow it */
368 if ((link->flags & MEDIA_LNK_FL_LINK_TYPE) != MEDIA_LNK_FL_DATA_LINK) {
369 link_top(graph) = link_top(graph)->next;
370 return;
373 /* The link is not enabled so we do not follow. */
374 if (!(link->flags & MEDIA_LNK_FL_ENABLED)) {
375 link_top(graph) = link_top(graph)->next;
376 dev_dbg(entity->graph_obj.mdev->dev,
377 "walk: skipping disabled link '%s':%u -> '%s':%u\n",
378 link->source->entity->name, link->source->index,
379 link->sink->entity->name, link->sink->index);
380 return;
383 /* Get the entity at the other end of the link. */
384 next = media_entity_other(entity, link);
386 /* Has the entity already been visited? */
387 if (media_entity_enum_test_and_set(&graph->ent_enum, next)) {
388 link_top(graph) = link_top(graph)->next;
389 dev_dbg(entity->graph_obj.mdev->dev,
390 "walk: skipping entity '%s' (already seen)\n",
391 next->name);
392 return;
395 /* Push the new entity to stack and start over. */
396 link_top(graph) = link_top(graph)->next;
397 stack_push(graph, next);
398 dev_dbg(entity->graph_obj.mdev->dev, "walk: pushing '%s' on stack\n",
399 next->name);
400 lockdep_assert_held(&entity->graph_obj.mdev->graph_mutex);
403 struct media_entity *media_graph_walk_next(struct media_graph *graph)
405 struct media_entity *entity;
407 if (stack_top(graph) == NULL)
408 return NULL;
411 * Depth first search. Push entity to stack and continue from
412 * top of the stack until no more entities on the level can be
413 * found.
415 while (link_top(graph) != &stack_top(graph)->links)
416 media_graph_walk_iter(graph);
418 entity = stack_pop(graph);
419 dev_dbg(entity->graph_obj.mdev->dev,
420 "walk: returning entity '%s'\n", entity->name);
422 return entity;
424 EXPORT_SYMBOL_GPL(media_graph_walk_next);
426 /* -----------------------------------------------------------------------------
427 * Pipeline management
431 * The pipeline traversal stack stores pads that are reached during graph
432 * traversal, with a list of links to be visited to continue the traversal.
433 * When a new pad is reached, an entry is pushed on the top of the stack and
434 * points to the incoming pad and the first link of the entity.
436 * To find further pads in the pipeline, the traversal algorithm follows
437 * internal pad dependencies in the entity, and then links in the graph. It
438 * does so by iterating over all links of the entity, and following enabled
439 * links that originate from a pad that is internally connected to the incoming
440 * pad, as reported by the media_entity_has_pad_interdep() function.
444 * struct media_pipeline_walk_entry - Entry in the pipeline traversal stack
446 * @pad: The media pad being visited
447 * @links: Links left to be visited
449 struct media_pipeline_walk_entry {
450 struct media_pad *pad;
451 struct list_head *links;
455 * struct media_pipeline_walk - State used by the media pipeline traversal
456 * algorithm
458 * @mdev: The media device
459 * @stack: Depth-first search stack
460 * @stack.size: Number of allocated entries in @stack.entries
461 * @stack.top: Index of the top stack entry (-1 if the stack is empty)
462 * @stack.entries: Stack entries
464 struct media_pipeline_walk {
465 struct media_device *mdev;
467 struct {
468 unsigned int size;
469 int top;
470 struct media_pipeline_walk_entry *entries;
471 } stack;
474 #define MEDIA_PIPELINE_STACK_GROW_STEP 16
476 static struct media_pipeline_walk_entry *
477 media_pipeline_walk_top(struct media_pipeline_walk *walk)
479 return &walk->stack.entries[walk->stack.top];
482 static bool media_pipeline_walk_empty(struct media_pipeline_walk *walk)
484 return walk->stack.top == -1;
487 /* Increase the stack size by MEDIA_PIPELINE_STACK_GROW_STEP elements. */
488 static int media_pipeline_walk_resize(struct media_pipeline_walk *walk)
490 struct media_pipeline_walk_entry *entries;
491 unsigned int new_size;
493 /* Safety check, to avoid stack overflows in case of bugs. */
494 if (walk->stack.size >= 256)
495 return -E2BIG;
497 new_size = walk->stack.size + MEDIA_PIPELINE_STACK_GROW_STEP;
499 entries = krealloc(walk->stack.entries,
500 new_size * sizeof(*walk->stack.entries),
501 GFP_KERNEL);
502 if (!entries)
503 return -ENOMEM;
505 walk->stack.entries = entries;
506 walk->stack.size = new_size;
508 return 0;
511 /* Push a new entry on the stack. */
512 static int media_pipeline_walk_push(struct media_pipeline_walk *walk,
513 struct media_pad *pad)
515 struct media_pipeline_walk_entry *entry;
516 int ret;
518 if (walk->stack.top + 1 >= walk->stack.size) {
519 ret = media_pipeline_walk_resize(walk);
520 if (ret)
521 return ret;
524 walk->stack.top++;
525 entry = media_pipeline_walk_top(walk);
526 entry->pad = pad;
527 entry->links = pad->entity->links.next;
529 dev_dbg(walk->mdev->dev,
530 "media pipeline: pushed entry %u: '%s':%u\n",
531 walk->stack.top, pad->entity->name, pad->index);
533 return 0;
537 * Move the top entry link cursor to the next link. If all links of the entry
538 * have been visited, pop the entry itself. Return true if the entry has been
539 * popped.
541 static bool media_pipeline_walk_pop(struct media_pipeline_walk *walk)
543 struct media_pipeline_walk_entry *entry;
545 if (WARN_ON(walk->stack.top < 0))
546 return false;
548 entry = media_pipeline_walk_top(walk);
550 if (entry->links->next == &entry->pad->entity->links) {
551 dev_dbg(walk->mdev->dev,
552 "media pipeline: entry %u has no more links, popping\n",
553 walk->stack.top);
555 walk->stack.top--;
556 return true;
559 entry->links = entry->links->next;
561 dev_dbg(walk->mdev->dev,
562 "media pipeline: moved entry %u to next link\n",
563 walk->stack.top);
565 return false;
568 /* Free all memory allocated while walking the pipeline. */
569 static void media_pipeline_walk_destroy(struct media_pipeline_walk *walk)
571 kfree(walk->stack.entries);
574 /* Add a pad to the pipeline and push it to the stack. */
575 static int media_pipeline_add_pad(struct media_pipeline *pipe,
576 struct media_pipeline_walk *walk,
577 struct media_pad *pad)
579 struct media_pipeline_pad *ppad;
581 list_for_each_entry(ppad, &pipe->pads, list) {
582 if (ppad->pad == pad) {
583 dev_dbg(pad->graph_obj.mdev->dev,
584 "media pipeline: already contains pad '%s':%u\n",
585 pad->entity->name, pad->index);
586 return 0;
590 ppad = kzalloc(sizeof(*ppad), GFP_KERNEL);
591 if (!ppad)
592 return -ENOMEM;
594 ppad->pipe = pipe;
595 ppad->pad = pad;
597 list_add_tail(&ppad->list, &pipe->pads);
599 dev_dbg(pad->graph_obj.mdev->dev,
600 "media pipeline: added pad '%s':%u\n",
601 pad->entity->name, pad->index);
603 return media_pipeline_walk_push(walk, pad);
606 /* Explore the next link of the entity at the top of the stack. */
607 static int media_pipeline_explore_next_link(struct media_pipeline *pipe,
608 struct media_pipeline_walk *walk)
610 struct media_pipeline_walk_entry *entry = media_pipeline_walk_top(walk);
611 struct media_pad *origin;
612 struct media_link *link;
613 struct media_pad *local;
614 struct media_pad *remote;
615 bool last_link;
616 int ret;
618 origin = entry->pad;
619 link = list_entry(entry->links, typeof(*link), list);
620 last_link = media_pipeline_walk_pop(walk);
622 if ((link->flags & MEDIA_LNK_FL_LINK_TYPE) != MEDIA_LNK_FL_DATA_LINK) {
623 dev_dbg(walk->mdev->dev,
624 "media pipeline: skipping link (not data-link)\n");
625 return 0;
628 dev_dbg(walk->mdev->dev,
629 "media pipeline: exploring link '%s':%u -> '%s':%u\n",
630 link->source->entity->name, link->source->index,
631 link->sink->entity->name, link->sink->index);
633 /* Get the local pad and remote pad. */
634 if (link->source->entity == origin->entity) {
635 local = link->source;
636 remote = link->sink;
637 } else {
638 local = link->sink;
639 remote = link->source;
643 * Skip links that originate from a different pad than the incoming pad
644 * that is not connected internally in the entity to the incoming pad.
646 if (origin != local &&
647 !media_entity_has_pad_interdep(origin->entity, origin->index,
648 local->index)) {
649 dev_dbg(walk->mdev->dev,
650 "media pipeline: skipping link (no route)\n");
651 goto done;
655 * Add the local pad of the link to the pipeline and push it to the
656 * stack, if not already present.
658 ret = media_pipeline_add_pad(pipe, walk, local);
659 if (ret)
660 return ret;
662 /* Similarly, add the remote pad, but only if the link is enabled. */
663 if (!(link->flags & MEDIA_LNK_FL_ENABLED)) {
664 dev_dbg(walk->mdev->dev,
665 "media pipeline: skipping link (disabled)\n");
666 goto done;
669 ret = media_pipeline_add_pad(pipe, walk, remote);
670 if (ret)
671 return ret;
673 done:
675 * If we're done iterating over links, iterate over pads of the entity.
676 * This is necessary to discover pads that are not connected with any
677 * link. Those are dead ends from a pipeline exploration point of view,
678 * but are still part of the pipeline and need to be added to enable
679 * proper validation.
681 if (!last_link)
682 return 0;
684 dev_dbg(walk->mdev->dev,
685 "media pipeline: adding unconnected pads of '%s'\n",
686 local->entity->name);
688 media_entity_for_each_pad(origin->entity, local) {
690 * Skip the origin pad (already handled), pad that have links
691 * (already discovered through iterating over links) and pads
692 * not internally connected.
694 if (origin == local || !local->num_links ||
695 !media_entity_has_pad_interdep(origin->entity, origin->index,
696 local->index))
697 continue;
699 ret = media_pipeline_add_pad(pipe, walk, local);
700 if (ret)
701 return ret;
704 return 0;
707 static void media_pipeline_cleanup(struct media_pipeline *pipe)
709 while (!list_empty(&pipe->pads)) {
710 struct media_pipeline_pad *ppad;
712 ppad = list_first_entry(&pipe->pads, typeof(*ppad), list);
713 list_del(&ppad->list);
714 kfree(ppad);
718 static int media_pipeline_populate(struct media_pipeline *pipe,
719 struct media_pad *pad)
721 struct media_pipeline_walk walk = { };
722 struct media_pipeline_pad *ppad;
723 int ret;
726 * Populate the media pipeline by walking the media graph, starting
727 * from @pad.
729 INIT_LIST_HEAD(&pipe->pads);
730 pipe->mdev = pad->graph_obj.mdev;
732 walk.mdev = pipe->mdev;
733 walk.stack.top = -1;
734 ret = media_pipeline_add_pad(pipe, &walk, pad);
735 if (ret)
736 goto done;
739 * Use a depth-first search algorithm: as long as the stack is not
740 * empty, explore the next link of the top entry. The
741 * media_pipeline_explore_next_link() function will either move to the
742 * next link, pop the entry if fully visited, or add new entries on
743 * top.
745 while (!media_pipeline_walk_empty(&walk)) {
746 ret = media_pipeline_explore_next_link(pipe, &walk);
747 if (ret)
748 goto done;
751 dev_dbg(pad->graph_obj.mdev->dev,
752 "media pipeline populated, found pads:\n");
754 list_for_each_entry(ppad, &pipe->pads, list)
755 dev_dbg(pad->graph_obj.mdev->dev, "- '%s':%u\n",
756 ppad->pad->entity->name, ppad->pad->index);
758 WARN_ON(walk.stack.top != -1);
760 ret = 0;
762 done:
763 media_pipeline_walk_destroy(&walk);
765 if (ret)
766 media_pipeline_cleanup(pipe);
768 return ret;
771 __must_check int __media_pipeline_start(struct media_pad *origin,
772 struct media_pipeline *pipe)
774 struct media_device *mdev = origin->graph_obj.mdev;
775 struct media_pipeline_pad *err_ppad;
776 struct media_pipeline_pad *ppad;
777 int ret;
779 lockdep_assert_held(&mdev->graph_mutex);
782 * If the pad is already part of a pipeline, that pipeline must be the
783 * same as the pipe given to media_pipeline_start().
785 if (WARN_ON(origin->pipe && origin->pipe != pipe))
786 return -EINVAL;
789 * If the pipeline has already been started, it is guaranteed to be
790 * valid, so just increase the start count.
792 if (pipe->start_count) {
793 pipe->start_count++;
794 return 0;
798 * Populate the pipeline. This populates the media_pipeline pads list
799 * with media_pipeline_pad instances for each pad found during graph
800 * walk.
802 ret = media_pipeline_populate(pipe, origin);
803 if (ret)
804 return ret;
807 * Now that all the pads in the pipeline have been gathered, perform
808 * the validation steps.
811 list_for_each_entry(ppad, &pipe->pads, list) {
812 struct media_pad *pad = ppad->pad;
813 struct media_entity *entity = pad->entity;
814 bool has_enabled_link = false;
815 struct media_link *link;
817 dev_dbg(mdev->dev, "Validating pad '%s':%u\n", pad->entity->name,
818 pad->index);
821 * 1. Ensure that the pad doesn't already belong to a different
822 * pipeline.
824 if (pad->pipe) {
825 dev_dbg(mdev->dev, "Failed to start pipeline: pad '%s':%u busy\n",
826 pad->entity->name, pad->index);
827 ret = -EBUSY;
828 goto error;
832 * 2. Validate all active links whose sink is the current pad.
833 * Validation of the source pads is performed in the context of
834 * the connected sink pad to avoid duplicating checks.
836 for_each_media_entity_data_link(entity, link) {
837 /* Skip links unrelated to the current pad. */
838 if (link->sink != pad && link->source != pad)
839 continue;
841 /* Record if the pad has links and enabled links. */
842 if (link->flags & MEDIA_LNK_FL_ENABLED)
843 has_enabled_link = true;
846 * Validate the link if it's enabled and has the
847 * current pad as its sink.
849 if (!(link->flags & MEDIA_LNK_FL_ENABLED))
850 continue;
852 if (link->sink != pad)
853 continue;
855 if (!entity->ops || !entity->ops->link_validate)
856 continue;
858 ret = entity->ops->link_validate(link);
859 if (ret) {
860 dev_dbg(mdev->dev,
861 "Link '%s':%u -> '%s':%u failed validation: %d\n",
862 link->source->entity->name,
863 link->source->index,
864 link->sink->entity->name,
865 link->sink->index, ret);
866 goto error;
869 dev_dbg(mdev->dev,
870 "Link '%s':%u -> '%s':%u is valid\n",
871 link->source->entity->name,
872 link->source->index,
873 link->sink->entity->name,
874 link->sink->index);
878 * 3. If the pad has the MEDIA_PAD_FL_MUST_CONNECT flag set,
879 * ensure that it has either no link or an enabled link.
881 if ((pad->flags & MEDIA_PAD_FL_MUST_CONNECT) &&
882 !has_enabled_link) {
883 dev_dbg(mdev->dev,
884 "Pad '%s':%u must be connected by an enabled link\n",
885 pad->entity->name, pad->index);
886 ret = -ENOLINK;
887 goto error;
890 /* Validation passed, store the pipe pointer in the pad. */
891 pad->pipe = pipe;
894 pipe->start_count++;
896 return 0;
898 error:
900 * Link validation on graph failed. We revert what we did and
901 * return the error.
904 list_for_each_entry(err_ppad, &pipe->pads, list) {
905 if (err_ppad == ppad)
906 break;
908 err_ppad->pad->pipe = NULL;
911 media_pipeline_cleanup(pipe);
913 return ret;
915 EXPORT_SYMBOL_GPL(__media_pipeline_start);
917 __must_check int media_pipeline_start(struct media_pad *origin,
918 struct media_pipeline *pipe)
920 struct media_device *mdev = origin->graph_obj.mdev;
921 int ret;
923 mutex_lock(&mdev->graph_mutex);
924 ret = __media_pipeline_start(origin, pipe);
925 mutex_unlock(&mdev->graph_mutex);
926 return ret;
928 EXPORT_SYMBOL_GPL(media_pipeline_start);
930 void __media_pipeline_stop(struct media_pad *pad)
932 struct media_pipeline *pipe = pad->pipe;
933 struct media_pipeline_pad *ppad;
936 * If the following check fails, the driver has performed an
937 * unbalanced call to media_pipeline_stop()
939 if (WARN_ON(!pipe))
940 return;
942 if (--pipe->start_count)
943 return;
945 list_for_each_entry(ppad, &pipe->pads, list)
946 ppad->pad->pipe = NULL;
948 media_pipeline_cleanup(pipe);
950 if (pipe->allocated)
951 kfree(pipe);
953 EXPORT_SYMBOL_GPL(__media_pipeline_stop);
955 void media_pipeline_stop(struct media_pad *pad)
957 struct media_device *mdev = pad->graph_obj.mdev;
959 mutex_lock(&mdev->graph_mutex);
960 __media_pipeline_stop(pad);
961 mutex_unlock(&mdev->graph_mutex);
963 EXPORT_SYMBOL_GPL(media_pipeline_stop);
965 __must_check int media_pipeline_alloc_start(struct media_pad *pad)
967 struct media_device *mdev = pad->graph_obj.mdev;
968 struct media_pipeline *new_pipe = NULL;
969 struct media_pipeline *pipe;
970 int ret;
972 mutex_lock(&mdev->graph_mutex);
975 * Is the pad already part of a pipeline? If not, we need to allocate
976 * a pipe.
978 pipe = media_pad_pipeline(pad);
979 if (!pipe) {
980 new_pipe = kzalloc(sizeof(*new_pipe), GFP_KERNEL);
981 if (!new_pipe) {
982 ret = -ENOMEM;
983 goto out;
986 pipe = new_pipe;
987 pipe->allocated = true;
990 ret = __media_pipeline_start(pad, pipe);
991 if (ret)
992 kfree(new_pipe);
994 out:
995 mutex_unlock(&mdev->graph_mutex);
997 return ret;
999 EXPORT_SYMBOL_GPL(media_pipeline_alloc_start);
1001 struct media_pad *
1002 __media_pipeline_pad_iter_next(struct media_pipeline *pipe,
1003 struct media_pipeline_pad_iter *iter,
1004 struct media_pad *pad)
1006 if (!pad)
1007 iter->cursor = pipe->pads.next;
1009 if (iter->cursor == &pipe->pads)
1010 return NULL;
1012 pad = list_entry(iter->cursor, struct media_pipeline_pad, list)->pad;
1013 iter->cursor = iter->cursor->next;
1015 return pad;
1017 EXPORT_SYMBOL_GPL(__media_pipeline_pad_iter_next);
1019 int media_pipeline_entity_iter_init(struct media_pipeline *pipe,
1020 struct media_pipeline_entity_iter *iter)
1022 return media_entity_enum_init(&iter->ent_enum, pipe->mdev);
1024 EXPORT_SYMBOL_GPL(media_pipeline_entity_iter_init);
1026 void media_pipeline_entity_iter_cleanup(struct media_pipeline_entity_iter *iter)
1028 media_entity_enum_cleanup(&iter->ent_enum);
1030 EXPORT_SYMBOL_GPL(media_pipeline_entity_iter_cleanup);
1032 struct media_entity *
1033 __media_pipeline_entity_iter_next(struct media_pipeline *pipe,
1034 struct media_pipeline_entity_iter *iter,
1035 struct media_entity *entity)
1037 if (!entity)
1038 iter->cursor = pipe->pads.next;
1040 while (iter->cursor != &pipe->pads) {
1041 struct media_pipeline_pad *ppad;
1042 struct media_entity *entity;
1044 ppad = list_entry(iter->cursor, struct media_pipeline_pad, list);
1045 entity = ppad->pad->entity;
1046 iter->cursor = iter->cursor->next;
1048 if (!media_entity_enum_test_and_set(&iter->ent_enum, entity))
1049 return entity;
1052 return NULL;
1054 EXPORT_SYMBOL_GPL(__media_pipeline_entity_iter_next);
1056 /* -----------------------------------------------------------------------------
1057 * Links management
1060 static struct media_link *media_add_link(struct list_head *head)
1062 struct media_link *link;
1064 link = kzalloc(sizeof(*link), GFP_KERNEL);
1065 if (link == NULL)
1066 return NULL;
1068 list_add_tail(&link->list, head);
1070 return link;
1073 static void __media_entity_remove_link(struct media_entity *entity,
1074 struct media_link *link)
1076 struct media_link *rlink, *tmp;
1077 struct media_entity *remote;
1079 /* Remove the reverse links for a data link. */
1080 if ((link->flags & MEDIA_LNK_FL_LINK_TYPE) == MEDIA_LNK_FL_DATA_LINK) {
1081 link->source->num_links--;
1082 link->sink->num_links--;
1084 if (link->source->entity == entity)
1085 remote = link->sink->entity;
1086 else
1087 remote = link->source->entity;
1089 list_for_each_entry_safe(rlink, tmp, &remote->links, list) {
1090 if (rlink != link->reverse)
1091 continue;
1093 if (link->source->entity == entity)
1094 remote->num_backlinks--;
1096 /* Remove the remote link */
1097 list_del(&rlink->list);
1098 media_gobj_destroy(&rlink->graph_obj);
1099 kfree(rlink);
1101 if (--remote->num_links == 0)
1102 break;
1106 list_del(&link->list);
1107 media_gobj_destroy(&link->graph_obj);
1108 kfree(link);
1111 int media_get_pad_index(struct media_entity *entity, u32 pad_type,
1112 enum media_pad_signal_type sig_type)
1114 unsigned int i;
1116 if (!entity)
1117 return -EINVAL;
1119 for (i = 0; i < entity->num_pads; i++) {
1120 if ((entity->pads[i].flags &
1121 (MEDIA_PAD_FL_SINK | MEDIA_PAD_FL_SOURCE)) != pad_type)
1122 continue;
1124 if (entity->pads[i].sig_type == sig_type)
1125 return i;
1127 return -EINVAL;
1129 EXPORT_SYMBOL_GPL(media_get_pad_index);
1132 media_create_pad_link(struct media_entity *source, u16 source_pad,
1133 struct media_entity *sink, u16 sink_pad, u32 flags)
1135 struct media_link *link;
1136 struct media_link *backlink;
1138 if (flags & MEDIA_LNK_FL_LINK_TYPE)
1139 return -EINVAL;
1141 flags |= MEDIA_LNK_FL_DATA_LINK;
1143 if (WARN_ON(!source || !sink) ||
1144 WARN_ON(source_pad >= source->num_pads) ||
1145 WARN_ON(sink_pad >= sink->num_pads))
1146 return -EINVAL;
1147 if (WARN_ON(!(source->pads[source_pad].flags & MEDIA_PAD_FL_SOURCE)))
1148 return -EINVAL;
1149 if (WARN_ON(!(sink->pads[sink_pad].flags & MEDIA_PAD_FL_SINK)))
1150 return -EINVAL;
1152 link = media_add_link(&source->links);
1153 if (link == NULL)
1154 return -ENOMEM;
1156 link->source = &source->pads[source_pad];
1157 link->sink = &sink->pads[sink_pad];
1158 link->flags = flags;
1160 /* Initialize graph object embedded at the new link */
1161 media_gobj_create(source->graph_obj.mdev, MEDIA_GRAPH_LINK,
1162 &link->graph_obj);
1164 /* Create the backlink. Backlinks are used to help graph traversal and
1165 * are not reported to userspace.
1167 backlink = media_add_link(&sink->links);
1168 if (backlink == NULL) {
1169 __media_entity_remove_link(source, link);
1170 return -ENOMEM;
1173 backlink->source = &source->pads[source_pad];
1174 backlink->sink = &sink->pads[sink_pad];
1175 backlink->flags = flags;
1176 backlink->is_backlink = true;
1178 /* Initialize graph object embedded at the new link */
1179 media_gobj_create(sink->graph_obj.mdev, MEDIA_GRAPH_LINK,
1180 &backlink->graph_obj);
1182 link->reverse = backlink;
1183 backlink->reverse = link;
1185 sink->num_backlinks++;
1186 sink->num_links++;
1187 source->num_links++;
1189 link->source->num_links++;
1190 link->sink->num_links++;
1192 return 0;
1194 EXPORT_SYMBOL_GPL(media_create_pad_link);
1196 int media_create_pad_links(const struct media_device *mdev,
1197 const u32 source_function,
1198 struct media_entity *source,
1199 const u16 source_pad,
1200 const u32 sink_function,
1201 struct media_entity *sink,
1202 const u16 sink_pad,
1203 u32 flags,
1204 const bool allow_both_undefined)
1206 struct media_entity *entity;
1207 unsigned function;
1208 int ret;
1210 /* Trivial case: 1:1 relation */
1211 if (source && sink)
1212 return media_create_pad_link(source, source_pad,
1213 sink, sink_pad, flags);
1215 /* Worse case scenario: n:n relation */
1216 if (!source && !sink) {
1217 if (!allow_both_undefined)
1218 return 0;
1219 media_device_for_each_entity(source, mdev) {
1220 if (source->function != source_function)
1221 continue;
1222 media_device_for_each_entity(sink, mdev) {
1223 if (sink->function != sink_function)
1224 continue;
1225 ret = media_create_pad_link(source, source_pad,
1226 sink, sink_pad,
1227 flags);
1228 if (ret)
1229 return ret;
1230 flags &= ~(MEDIA_LNK_FL_ENABLED |
1231 MEDIA_LNK_FL_IMMUTABLE);
1234 return 0;
1237 /* Handle 1:n and n:1 cases */
1238 if (source)
1239 function = sink_function;
1240 else
1241 function = source_function;
1243 media_device_for_each_entity(entity, mdev) {
1244 if (entity->function != function)
1245 continue;
1247 if (source)
1248 ret = media_create_pad_link(source, source_pad,
1249 entity, sink_pad, flags);
1250 else
1251 ret = media_create_pad_link(entity, source_pad,
1252 sink, sink_pad, flags);
1253 if (ret)
1254 return ret;
1255 flags &= ~(MEDIA_LNK_FL_ENABLED | MEDIA_LNK_FL_IMMUTABLE);
1257 return 0;
1259 EXPORT_SYMBOL_GPL(media_create_pad_links);
1261 void __media_entity_remove_links(struct media_entity *entity)
1263 struct media_link *link, *tmp;
1265 list_for_each_entry_safe(link, tmp, &entity->links, list)
1266 __media_entity_remove_link(entity, link);
1268 entity->num_links = 0;
1269 entity->num_backlinks = 0;
1271 EXPORT_SYMBOL_GPL(__media_entity_remove_links);
1273 void media_entity_remove_links(struct media_entity *entity)
1275 struct media_device *mdev = entity->graph_obj.mdev;
1277 /* Do nothing if the entity is not registered. */
1278 if (mdev == NULL)
1279 return;
1281 mutex_lock(&mdev->graph_mutex);
1282 __media_entity_remove_links(entity);
1283 mutex_unlock(&mdev->graph_mutex);
1285 EXPORT_SYMBOL_GPL(media_entity_remove_links);
1287 static int __media_entity_setup_link_notify(struct media_link *link, u32 flags)
1289 int ret;
1291 /* Notify both entities. */
1292 ret = media_entity_call(link->source->entity, link_setup,
1293 link->source, link->sink, flags);
1294 if (ret < 0 && ret != -ENOIOCTLCMD)
1295 return ret;
1297 ret = media_entity_call(link->sink->entity, link_setup,
1298 link->sink, link->source, flags);
1299 if (ret < 0 && ret != -ENOIOCTLCMD) {
1300 media_entity_call(link->source->entity, link_setup,
1301 link->source, link->sink, link->flags);
1302 return ret;
1305 link->flags = flags;
1306 link->reverse->flags = link->flags;
1308 return 0;
1311 int __media_entity_setup_link(struct media_link *link, u32 flags)
1313 const u32 mask = MEDIA_LNK_FL_ENABLED;
1314 struct media_device *mdev;
1315 struct media_pad *source, *sink;
1316 int ret = -EBUSY;
1318 if (link == NULL)
1319 return -EINVAL;
1321 /* The non-modifiable link flags must not be modified. */
1322 if ((link->flags & ~mask) != (flags & ~mask))
1323 return -EINVAL;
1325 if (link->flags & MEDIA_LNK_FL_IMMUTABLE)
1326 return link->flags == flags ? 0 : -EINVAL;
1328 if (link->flags == flags)
1329 return 0;
1331 source = link->source;
1332 sink = link->sink;
1334 if (!(link->flags & MEDIA_LNK_FL_DYNAMIC) &&
1335 (media_pad_is_streaming(source) || media_pad_is_streaming(sink)))
1336 return -EBUSY;
1338 mdev = source->graph_obj.mdev;
1340 if (mdev->ops && mdev->ops->link_notify) {
1341 ret = mdev->ops->link_notify(link, flags,
1342 MEDIA_DEV_NOTIFY_PRE_LINK_CH);
1343 if (ret < 0)
1344 return ret;
1347 ret = __media_entity_setup_link_notify(link, flags);
1349 if (mdev->ops && mdev->ops->link_notify)
1350 mdev->ops->link_notify(link, flags,
1351 MEDIA_DEV_NOTIFY_POST_LINK_CH);
1353 return ret;
1355 EXPORT_SYMBOL_GPL(__media_entity_setup_link);
1357 int media_entity_setup_link(struct media_link *link, u32 flags)
1359 int ret;
1361 mutex_lock(&link->graph_obj.mdev->graph_mutex);
1362 ret = __media_entity_setup_link(link, flags);
1363 mutex_unlock(&link->graph_obj.mdev->graph_mutex);
1365 return ret;
1367 EXPORT_SYMBOL_GPL(media_entity_setup_link);
1369 struct media_link *
1370 media_entity_find_link(struct media_pad *source, struct media_pad *sink)
1372 struct media_link *link;
1374 for_each_media_entity_data_link(source->entity, link) {
1375 if (link->source->entity == source->entity &&
1376 link->source->index == source->index &&
1377 link->sink->entity == sink->entity &&
1378 link->sink->index == sink->index)
1379 return link;
1382 return NULL;
1384 EXPORT_SYMBOL_GPL(media_entity_find_link);
1386 struct media_pad *media_pad_remote_pad_first(const struct media_pad *pad)
1388 struct media_link *link;
1390 for_each_media_entity_data_link(pad->entity, link) {
1391 if (!(link->flags & MEDIA_LNK_FL_ENABLED))
1392 continue;
1394 if (link->source == pad)
1395 return link->sink;
1397 if (link->sink == pad)
1398 return link->source;
1401 return NULL;
1404 EXPORT_SYMBOL_GPL(media_pad_remote_pad_first);
1406 struct media_pad *
1407 media_entity_remote_pad_unique(const struct media_entity *entity,
1408 unsigned int type)
1410 struct media_pad *pad = NULL;
1411 struct media_link *link;
1413 list_for_each_entry(link, &entity->links, list) {
1414 struct media_pad *local_pad;
1415 struct media_pad *remote_pad;
1417 if (((link->flags & MEDIA_LNK_FL_LINK_TYPE) !=
1418 MEDIA_LNK_FL_DATA_LINK) ||
1419 !(link->flags & MEDIA_LNK_FL_ENABLED))
1420 continue;
1422 if (type == MEDIA_PAD_FL_SOURCE) {
1423 local_pad = link->sink;
1424 remote_pad = link->source;
1425 } else {
1426 local_pad = link->source;
1427 remote_pad = link->sink;
1430 if (local_pad->entity == entity) {
1431 if (pad)
1432 return ERR_PTR(-ENOTUNIQ);
1434 pad = remote_pad;
1438 if (!pad)
1439 return ERR_PTR(-ENOLINK);
1441 return pad;
1443 EXPORT_SYMBOL_GPL(media_entity_remote_pad_unique);
1445 struct media_pad *media_pad_remote_pad_unique(const struct media_pad *pad)
1447 struct media_pad *found_pad = NULL;
1448 struct media_link *link;
1450 list_for_each_entry(link, &pad->entity->links, list) {
1451 struct media_pad *remote_pad;
1453 if (!(link->flags & MEDIA_LNK_FL_ENABLED))
1454 continue;
1456 if (link->sink == pad)
1457 remote_pad = link->source;
1458 else if (link->source == pad)
1459 remote_pad = link->sink;
1460 else
1461 continue;
1463 if (found_pad)
1464 return ERR_PTR(-ENOTUNIQ);
1466 found_pad = remote_pad;
1469 if (!found_pad)
1470 return ERR_PTR(-ENOLINK);
1472 return found_pad;
1474 EXPORT_SYMBOL_GPL(media_pad_remote_pad_unique);
1476 int media_entity_get_fwnode_pad(struct media_entity *entity,
1477 const struct fwnode_handle *fwnode,
1478 unsigned long direction_flags)
1480 struct fwnode_endpoint endpoint;
1481 unsigned int i;
1482 int ret;
1484 if (!entity->ops || !entity->ops->get_fwnode_pad) {
1485 for (i = 0; i < entity->num_pads; i++) {
1486 if (entity->pads[i].flags & direction_flags)
1487 return i;
1490 return -ENXIO;
1493 ret = fwnode_graph_parse_endpoint(fwnode, &endpoint);
1494 if (ret)
1495 return ret;
1497 ret = entity->ops->get_fwnode_pad(entity, &endpoint);
1498 if (ret < 0)
1499 return ret;
1501 if (ret >= entity->num_pads)
1502 return -ENXIO;
1504 if (!(entity->pads[ret].flags & direction_flags))
1505 return -ENXIO;
1507 return ret;
1509 EXPORT_SYMBOL_GPL(media_entity_get_fwnode_pad);
1511 struct media_pipeline *media_entity_pipeline(struct media_entity *entity)
1513 struct media_pad *pad;
1515 media_entity_for_each_pad(entity, pad) {
1516 if (pad->pipe)
1517 return pad->pipe;
1520 return NULL;
1522 EXPORT_SYMBOL_GPL(media_entity_pipeline);
1524 struct media_pipeline *media_pad_pipeline(struct media_pad *pad)
1526 return pad->pipe;
1528 EXPORT_SYMBOL_GPL(media_pad_pipeline);
1530 static void media_interface_init(struct media_device *mdev,
1531 struct media_interface *intf,
1532 u32 gobj_type,
1533 u32 intf_type, u32 flags)
1535 intf->type = intf_type;
1536 intf->flags = flags;
1537 INIT_LIST_HEAD(&intf->links);
1539 media_gobj_create(mdev, gobj_type, &intf->graph_obj);
1542 /* Functions related to the media interface via device nodes */
1544 struct media_intf_devnode *media_devnode_create(struct media_device *mdev,
1545 u32 type, u32 flags,
1546 u32 major, u32 minor)
1548 struct media_intf_devnode *devnode;
1550 devnode = kzalloc(sizeof(*devnode), GFP_KERNEL);
1551 if (!devnode)
1552 return NULL;
1554 devnode->major = major;
1555 devnode->minor = minor;
1557 media_interface_init(mdev, &devnode->intf, MEDIA_GRAPH_INTF_DEVNODE,
1558 type, flags);
1560 return devnode;
1562 EXPORT_SYMBOL_GPL(media_devnode_create);
1564 void media_devnode_remove(struct media_intf_devnode *devnode)
1566 media_remove_intf_links(&devnode->intf);
1567 media_gobj_destroy(&devnode->intf.graph_obj);
1568 kfree(devnode);
1570 EXPORT_SYMBOL_GPL(media_devnode_remove);
1572 struct media_link *media_create_intf_link(struct media_entity *entity,
1573 struct media_interface *intf,
1574 u32 flags)
1576 struct media_link *link;
1578 link = media_add_link(&intf->links);
1579 if (link == NULL)
1580 return NULL;
1582 link->intf = intf;
1583 link->entity = entity;
1584 link->flags = flags | MEDIA_LNK_FL_INTERFACE_LINK;
1586 /* Initialize graph object embedded at the new link */
1587 media_gobj_create(intf->graph_obj.mdev, MEDIA_GRAPH_LINK,
1588 &link->graph_obj);
1590 return link;
1592 EXPORT_SYMBOL_GPL(media_create_intf_link);
1594 void __media_remove_intf_link(struct media_link *link)
1596 list_del(&link->list);
1597 media_gobj_destroy(&link->graph_obj);
1598 kfree(link);
1600 EXPORT_SYMBOL_GPL(__media_remove_intf_link);
1602 void media_remove_intf_link(struct media_link *link)
1604 struct media_device *mdev = link->graph_obj.mdev;
1606 /* Do nothing if the intf is not registered. */
1607 if (mdev == NULL)
1608 return;
1610 mutex_lock(&mdev->graph_mutex);
1611 __media_remove_intf_link(link);
1612 mutex_unlock(&mdev->graph_mutex);
1614 EXPORT_SYMBOL_GPL(media_remove_intf_link);
1616 void __media_remove_intf_links(struct media_interface *intf)
1618 struct media_link *link, *tmp;
1620 list_for_each_entry_safe(link, tmp, &intf->links, list)
1621 __media_remove_intf_link(link);
1624 EXPORT_SYMBOL_GPL(__media_remove_intf_links);
1626 void media_remove_intf_links(struct media_interface *intf)
1628 struct media_device *mdev = intf->graph_obj.mdev;
1630 /* Do nothing if the intf is not registered. */
1631 if (mdev == NULL)
1632 return;
1634 mutex_lock(&mdev->graph_mutex);
1635 __media_remove_intf_links(intf);
1636 mutex_unlock(&mdev->graph_mutex);
1638 EXPORT_SYMBOL_GPL(media_remove_intf_links);
1640 struct media_link *media_create_ancillary_link(struct media_entity *primary,
1641 struct media_entity *ancillary)
1643 struct media_link *link;
1645 link = media_add_link(&primary->links);
1646 if (!link)
1647 return ERR_PTR(-ENOMEM);
1649 link->gobj0 = &primary->graph_obj;
1650 link->gobj1 = &ancillary->graph_obj;
1651 link->flags = MEDIA_LNK_FL_IMMUTABLE | MEDIA_LNK_FL_ENABLED |
1652 MEDIA_LNK_FL_ANCILLARY_LINK;
1654 /* Initialize graph object embedded in the new link */
1655 media_gobj_create(primary->graph_obj.mdev, MEDIA_GRAPH_LINK,
1656 &link->graph_obj);
1658 return link;
1660 EXPORT_SYMBOL_GPL(media_create_ancillary_link);
1662 struct media_link *__media_entity_next_link(struct media_entity *entity,
1663 struct media_link *link,
1664 unsigned long link_type)
1666 link = link ? list_next_entry(link, list)
1667 : list_first_entry(&entity->links, typeof(*link), list);
1669 list_for_each_entry_from(link, &entity->links, list)
1670 if ((link->flags & MEDIA_LNK_FL_LINK_TYPE) == link_type)
1671 return link;
1673 return NULL;
1675 EXPORT_SYMBOL_GPL(__media_entity_next_link);