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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/media/mc/mc-entity.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/media/mc/mc-entity.c')
-rw-r--r--drivers/media/mc/mc-entity.c1611
1 files changed, 1611 insertions, 0 deletions
diff --git a/drivers/media/mc/mc-entity.c b/drivers/media/mc/mc-entity.c
new file mode 100644
index 0000000000..83468d4a44
--- /dev/null
+++ b/drivers/media/mc/mc-entity.c
@@ -0,0 +1,1611 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Media entity
+ *
+ * Copyright (C) 2010 Nokia Corporation
+ *
+ * Contacts: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+ * Sakari Ailus <sakari.ailus@iki.fi>
+ */
+
+#include <linux/bitmap.h>
+#include <linux/list.h>
+#include <linux/property.h>
+#include <linux/slab.h>
+#include <media/media-entity.h>
+#include <media/media-device.h>
+
+static inline const char *intf_type(struct media_interface *intf)
+{
+ switch (intf->type) {
+ case MEDIA_INTF_T_DVB_FE:
+ return "dvb-frontend";
+ case MEDIA_INTF_T_DVB_DEMUX:
+ return "dvb-demux";
+ case MEDIA_INTF_T_DVB_DVR:
+ return "dvb-dvr";
+ case MEDIA_INTF_T_DVB_CA:
+ return "dvb-ca";
+ case MEDIA_INTF_T_DVB_NET:
+ return "dvb-net";
+ case MEDIA_INTF_T_V4L_VIDEO:
+ return "v4l-video";
+ case MEDIA_INTF_T_V4L_VBI:
+ return "v4l-vbi";
+ case MEDIA_INTF_T_V4L_RADIO:
+ return "v4l-radio";
+ case MEDIA_INTF_T_V4L_SUBDEV:
+ return "v4l-subdev";
+ case MEDIA_INTF_T_V4L_SWRADIO:
+ return "v4l-swradio";
+ case MEDIA_INTF_T_V4L_TOUCH:
+ return "v4l-touch";
+ default:
+ return "unknown-intf";
+ }
+};
+
+static inline const char *link_type_name(struct media_link *link)
+{
+ switch (link->flags & MEDIA_LNK_FL_LINK_TYPE) {
+ case MEDIA_LNK_FL_DATA_LINK:
+ return "data";
+ case MEDIA_LNK_FL_INTERFACE_LINK:
+ return "interface";
+ case MEDIA_LNK_FL_ANCILLARY_LINK:
+ return "ancillary";
+ default:
+ return "unknown";
+ }
+}
+
+__must_check int media_entity_enum_init(struct media_entity_enum *ent_enum,
+ struct media_device *mdev)
+{
+ int idx_max;
+
+ idx_max = ALIGN(mdev->entity_internal_idx_max + 1, BITS_PER_LONG);
+ ent_enum->bmap = bitmap_zalloc(idx_max, GFP_KERNEL);
+ if (!ent_enum->bmap)
+ return -ENOMEM;
+
+ ent_enum->idx_max = idx_max;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(media_entity_enum_init);
+
+void media_entity_enum_cleanup(struct media_entity_enum *ent_enum)
+{
+ bitmap_free(ent_enum->bmap);
+}
+EXPORT_SYMBOL_GPL(media_entity_enum_cleanup);
+
+/**
+ * dev_dbg_obj - Prints in debug mode a change on some object
+ *
+ * @event_name: Name of the event to report. Could be __func__
+ * @gobj: Pointer to the object
+ *
+ * Enabled only if DEBUG or CONFIG_DYNAMIC_DEBUG. Otherwise, it
+ * won't produce any code.
+ */
+static void dev_dbg_obj(const char *event_name, struct media_gobj *gobj)
+{
+#if defined(DEBUG) || defined (CONFIG_DYNAMIC_DEBUG)
+ switch (media_type(gobj)) {
+ case MEDIA_GRAPH_ENTITY:
+ dev_dbg(gobj->mdev->dev,
+ "%s id %u: entity '%s'\n",
+ event_name, media_id(gobj),
+ gobj_to_entity(gobj)->name);
+ break;
+ case MEDIA_GRAPH_LINK:
+ {
+ struct media_link *link = gobj_to_link(gobj);
+
+ dev_dbg(gobj->mdev->dev,
+ "%s id %u: %s link id %u ==> id %u\n",
+ event_name, media_id(gobj), link_type_name(link),
+ media_id(link->gobj0),
+ media_id(link->gobj1));
+ break;
+ }
+ case MEDIA_GRAPH_PAD:
+ {
+ struct media_pad *pad = gobj_to_pad(gobj);
+
+ dev_dbg(gobj->mdev->dev,
+ "%s id %u: %s%spad '%s':%d\n",
+ event_name, media_id(gobj),
+ pad->flags & MEDIA_PAD_FL_SINK ? "sink " : "",
+ pad->flags & MEDIA_PAD_FL_SOURCE ? "source " : "",
+ pad->entity->name, pad->index);
+ break;
+ }
+ case MEDIA_GRAPH_INTF_DEVNODE:
+ {
+ struct media_interface *intf = gobj_to_intf(gobj);
+ struct media_intf_devnode *devnode = intf_to_devnode(intf);
+
+ dev_dbg(gobj->mdev->dev,
+ "%s id %u: intf_devnode %s - major: %d, minor: %d\n",
+ event_name, media_id(gobj),
+ intf_type(intf),
+ devnode->major, devnode->minor);
+ break;
+ }
+ }
+#endif
+}
+
+void media_gobj_create(struct media_device *mdev,
+ enum media_gobj_type type,
+ struct media_gobj *gobj)
+{
+ BUG_ON(!mdev);
+
+ gobj->mdev = mdev;
+
+ /* Create a per-type unique object ID */
+ gobj->id = media_gobj_gen_id(type, ++mdev->id);
+
+ switch (type) {
+ case MEDIA_GRAPH_ENTITY:
+ list_add_tail(&gobj->list, &mdev->entities);
+ break;
+ case MEDIA_GRAPH_PAD:
+ list_add_tail(&gobj->list, &mdev->pads);
+ break;
+ case MEDIA_GRAPH_LINK:
+ list_add_tail(&gobj->list, &mdev->links);
+ break;
+ case MEDIA_GRAPH_INTF_DEVNODE:
+ list_add_tail(&gobj->list, &mdev->interfaces);
+ break;
+ }
+
+ mdev->topology_version++;
+
+ dev_dbg_obj(__func__, gobj);
+}
+
+void media_gobj_destroy(struct media_gobj *gobj)
+{
+ /* Do nothing if the object is not linked. */
+ if (gobj->mdev == NULL)
+ return;
+
+ dev_dbg_obj(__func__, gobj);
+
+ gobj->mdev->topology_version++;
+
+ /* Remove the object from mdev list */
+ list_del(&gobj->list);
+
+ gobj->mdev = NULL;
+}
+
+/*
+ * TODO: Get rid of this.
+ */
+#define MEDIA_ENTITY_MAX_PADS 512
+
+int media_entity_pads_init(struct media_entity *entity, u16 num_pads,
+ struct media_pad *pads)
+{
+ struct media_device *mdev = entity->graph_obj.mdev;
+ struct media_pad *iter;
+ unsigned int i = 0;
+
+ if (num_pads >= MEDIA_ENTITY_MAX_PADS)
+ return -E2BIG;
+
+ entity->num_pads = num_pads;
+ entity->pads = pads;
+
+ if (mdev)
+ mutex_lock(&mdev->graph_mutex);
+
+ media_entity_for_each_pad(entity, iter) {
+ iter->entity = entity;
+ iter->index = i++;
+ if (mdev)
+ media_gobj_create(mdev, MEDIA_GRAPH_PAD,
+ &iter->graph_obj);
+ }
+
+ if (mdev)
+ mutex_unlock(&mdev->graph_mutex);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(media_entity_pads_init);
+
+/* -----------------------------------------------------------------------------
+ * Graph traversal
+ */
+
+/**
+ * media_entity_has_pad_interdep - Check interdependency between two pads
+ *
+ * @entity: The entity
+ * @pad0: The first pad index
+ * @pad1: The second pad index
+ *
+ * This function checks the interdependency inside the entity between @pad0
+ * and @pad1. If two pads are interdependent they are part of the same pipeline
+ * and enabling one of the pads means that the other pad will become "locked"
+ * and doesn't allow configuration changes.
+ *
+ * This function uses the &media_entity_operations.has_pad_interdep() operation
+ * to check the dependency inside the entity between @pad0 and @pad1. If the
+ * has_pad_interdep operation is not implemented, all pads of the entity are
+ * considered to be interdependent.
+ *
+ * One of @pad0 and @pad1 must be a sink pad and the other one a source pad.
+ * The function returns false if both pads are sinks or sources.
+ *
+ * The caller must hold entity->graph_obj.mdev->mutex.
+ *
+ * Return: true if the pads are connected internally and false otherwise.
+ */
+static bool media_entity_has_pad_interdep(struct media_entity *entity,
+ unsigned int pad0, unsigned int pad1)
+{
+ if (pad0 >= entity->num_pads || pad1 >= entity->num_pads)
+ return false;
+
+ if (entity->pads[pad0].flags & entity->pads[pad1].flags &
+ (MEDIA_PAD_FL_SINK | MEDIA_PAD_FL_SOURCE))
+ return false;
+
+ if (!entity->ops || !entity->ops->has_pad_interdep)
+ return true;
+
+ return entity->ops->has_pad_interdep(entity, pad0, pad1);
+}
+
+static struct media_entity *
+media_entity_other(struct media_entity *entity, struct media_link *link)
+{
+ if (link->source->entity == entity)
+ return link->sink->entity;
+ else
+ return link->source->entity;
+}
+
+/* push an entity to traversal stack */
+static void stack_push(struct media_graph *graph,
+ struct media_entity *entity)
+{
+ if (graph->top == MEDIA_ENTITY_ENUM_MAX_DEPTH - 1) {
+ WARN_ON(1);
+ return;
+ }
+ graph->top++;
+ graph->stack[graph->top].link = entity->links.next;
+ graph->stack[graph->top].entity = entity;
+}
+
+static struct media_entity *stack_pop(struct media_graph *graph)
+{
+ struct media_entity *entity;
+
+ entity = graph->stack[graph->top].entity;
+ graph->top--;
+
+ return entity;
+}
+
+#define link_top(en) ((en)->stack[(en)->top].link)
+#define stack_top(en) ((en)->stack[(en)->top].entity)
+
+/**
+ * media_graph_walk_init - Allocate resources for graph walk
+ * @graph: Media graph structure that will be used to walk the graph
+ * @mdev: Media device
+ *
+ * Reserve resources for graph walk in media device's current
+ * state. The memory must be released using
+ * media_graph_walk_cleanup().
+ *
+ * Returns error on failure, zero on success.
+ */
+__must_check int media_graph_walk_init(
+ struct media_graph *graph, struct media_device *mdev)
+{
+ return media_entity_enum_init(&graph->ent_enum, mdev);
+}
+EXPORT_SYMBOL_GPL(media_graph_walk_init);
+
+/**
+ * media_graph_walk_cleanup - Release resources related to graph walking
+ * @graph: Media graph structure that was used to walk the graph
+ */
+void media_graph_walk_cleanup(struct media_graph *graph)
+{
+ media_entity_enum_cleanup(&graph->ent_enum);
+}
+EXPORT_SYMBOL_GPL(media_graph_walk_cleanup);
+
+void media_graph_walk_start(struct media_graph *graph,
+ struct media_entity *entity)
+{
+ media_entity_enum_zero(&graph->ent_enum);
+ media_entity_enum_set(&graph->ent_enum, entity);
+
+ graph->top = 0;
+ graph->stack[graph->top].entity = NULL;
+ stack_push(graph, entity);
+ dev_dbg(entity->graph_obj.mdev->dev,
+ "begin graph walk at '%s'\n", entity->name);
+}
+EXPORT_SYMBOL_GPL(media_graph_walk_start);
+
+static void media_graph_walk_iter(struct media_graph *graph)
+{
+ struct media_entity *entity = stack_top(graph);
+ struct media_link *link;
+ struct media_entity *next;
+
+ link = list_entry(link_top(graph), typeof(*link), list);
+
+ /* If the link is not a data link, don't follow it */
+ if ((link->flags & MEDIA_LNK_FL_LINK_TYPE) != MEDIA_LNK_FL_DATA_LINK) {
+ link_top(graph) = link_top(graph)->next;
+ return;
+ }
+
+ /* The link is not enabled so we do not follow. */
+ if (!(link->flags & MEDIA_LNK_FL_ENABLED)) {
+ link_top(graph) = link_top(graph)->next;
+ dev_dbg(entity->graph_obj.mdev->dev,
+ "walk: skipping disabled link '%s':%u -> '%s':%u\n",
+ link->source->entity->name, link->source->index,
+ link->sink->entity->name, link->sink->index);
+ return;
+ }
+
+ /* Get the entity at the other end of the link. */
+ next = media_entity_other(entity, link);
+
+ /* Has the entity already been visited? */
+ if (media_entity_enum_test_and_set(&graph->ent_enum, next)) {
+ link_top(graph) = link_top(graph)->next;
+ dev_dbg(entity->graph_obj.mdev->dev,
+ "walk: skipping entity '%s' (already seen)\n",
+ next->name);
+ return;
+ }
+
+ /* Push the new entity to stack and start over. */
+ link_top(graph) = link_top(graph)->next;
+ stack_push(graph, next);
+ dev_dbg(entity->graph_obj.mdev->dev, "walk: pushing '%s' on stack\n",
+ next->name);
+ lockdep_assert_held(&entity->graph_obj.mdev->graph_mutex);
+}
+
+struct media_entity *media_graph_walk_next(struct media_graph *graph)
+{
+ struct media_entity *entity;
+
+ if (stack_top(graph) == NULL)
+ return NULL;
+
+ /*
+ * Depth first search. Push entity to stack and continue from
+ * top of the stack until no more entities on the level can be
+ * found.
+ */
+ while (link_top(graph) != &stack_top(graph)->links)
+ media_graph_walk_iter(graph);
+
+ entity = stack_pop(graph);
+ dev_dbg(entity->graph_obj.mdev->dev,
+ "walk: returning entity '%s'\n", entity->name);
+
+ return entity;
+}
+EXPORT_SYMBOL_GPL(media_graph_walk_next);
+
+/* -----------------------------------------------------------------------------
+ * Pipeline management
+ */
+
+/*
+ * The pipeline traversal stack stores pads that are reached during graph
+ * traversal, with a list of links to be visited to continue the traversal.
+ * When a new pad is reached, an entry is pushed on the top of the stack and
+ * points to the incoming pad and the first link of the entity.
+ *
+ * To find further pads in the pipeline, the traversal algorithm follows
+ * internal pad dependencies in the entity, and then links in the graph. It
+ * does so by iterating over all links of the entity, and following enabled
+ * links that originate from a pad that is internally connected to the incoming
+ * pad, as reported by the media_entity_has_pad_interdep() function.
+ */
+
+/**
+ * struct media_pipeline_walk_entry - Entry in the pipeline traversal stack
+ *
+ * @pad: The media pad being visited
+ * @links: Links left to be visited
+ */
+struct media_pipeline_walk_entry {
+ struct media_pad *pad;
+ struct list_head *links;
+};
+
+/**
+ * struct media_pipeline_walk - State used by the media pipeline traversal
+ * algorithm
+ *
+ * @mdev: The media device
+ * @stack: Depth-first search stack
+ * @stack.size: Number of allocated entries in @stack.entries
+ * @stack.top: Index of the top stack entry (-1 if the stack is empty)
+ * @stack.entries: Stack entries
+ */
+struct media_pipeline_walk {
+ struct media_device *mdev;
+
+ struct {
+ unsigned int size;
+ int top;
+ struct media_pipeline_walk_entry *entries;
+ } stack;
+};
+
+#define MEDIA_PIPELINE_STACK_GROW_STEP 16
+
+static struct media_pipeline_walk_entry *
+media_pipeline_walk_top(struct media_pipeline_walk *walk)
+{
+ return &walk->stack.entries[walk->stack.top];
+}
+
+static bool media_pipeline_walk_empty(struct media_pipeline_walk *walk)
+{
+ return walk->stack.top == -1;
+}
+
+/* Increase the stack size by MEDIA_PIPELINE_STACK_GROW_STEP elements. */
+static int media_pipeline_walk_resize(struct media_pipeline_walk *walk)
+{
+ struct media_pipeline_walk_entry *entries;
+ unsigned int new_size;
+
+ /* Safety check, to avoid stack overflows in case of bugs. */
+ if (walk->stack.size >= 256)
+ return -E2BIG;
+
+ new_size = walk->stack.size + MEDIA_PIPELINE_STACK_GROW_STEP;
+
+ entries = krealloc(walk->stack.entries,
+ new_size * sizeof(*walk->stack.entries),
+ GFP_KERNEL);
+ if (!entries)
+ return -ENOMEM;
+
+ walk->stack.entries = entries;
+ walk->stack.size = new_size;
+
+ return 0;
+}
+
+/* Push a new entry on the stack. */
+static int media_pipeline_walk_push(struct media_pipeline_walk *walk,
+ struct media_pad *pad)
+{
+ struct media_pipeline_walk_entry *entry;
+ int ret;
+
+ if (walk->stack.top + 1 >= walk->stack.size) {
+ ret = media_pipeline_walk_resize(walk);
+ if (ret)
+ return ret;
+ }
+
+ walk->stack.top++;
+ entry = media_pipeline_walk_top(walk);
+ entry->pad = pad;
+ entry->links = pad->entity->links.next;
+
+ dev_dbg(walk->mdev->dev,
+ "media pipeline: pushed entry %u: '%s':%u\n",
+ walk->stack.top, pad->entity->name, pad->index);
+
+ return 0;
+}
+
+/*
+ * Move the top entry link cursor to the next link. If all links of the entry
+ * have been visited, pop the entry itself.
+ */
+static void media_pipeline_walk_pop(struct media_pipeline_walk *walk)
+{
+ struct media_pipeline_walk_entry *entry;
+
+ if (WARN_ON(walk->stack.top < 0))
+ return;
+
+ entry = media_pipeline_walk_top(walk);
+
+ if (entry->links->next == &entry->pad->entity->links) {
+ dev_dbg(walk->mdev->dev,
+ "media pipeline: entry %u has no more links, popping\n",
+ walk->stack.top);
+
+ walk->stack.top--;
+ return;
+ }
+
+ entry->links = entry->links->next;
+
+ dev_dbg(walk->mdev->dev,
+ "media pipeline: moved entry %u to next link\n",
+ walk->stack.top);
+}
+
+/* Free all memory allocated while walking the pipeline. */
+static void media_pipeline_walk_destroy(struct media_pipeline_walk *walk)
+{
+ kfree(walk->stack.entries);
+}
+
+/* Add a pad to the pipeline and push it to the stack. */
+static int media_pipeline_add_pad(struct media_pipeline *pipe,
+ struct media_pipeline_walk *walk,
+ struct media_pad *pad)
+{
+ struct media_pipeline_pad *ppad;
+
+ list_for_each_entry(ppad, &pipe->pads, list) {
+ if (ppad->pad == pad) {
+ dev_dbg(pad->graph_obj.mdev->dev,
+ "media pipeline: already contains pad '%s':%u\n",
+ pad->entity->name, pad->index);
+ return 0;
+ }
+ }
+
+ ppad = kzalloc(sizeof(*ppad), GFP_KERNEL);
+ if (!ppad)
+ return -ENOMEM;
+
+ ppad->pipe = pipe;
+ ppad->pad = pad;
+
+ list_add_tail(&ppad->list, &pipe->pads);
+
+ dev_dbg(pad->graph_obj.mdev->dev,
+ "media pipeline: added pad '%s':%u\n",
+ pad->entity->name, pad->index);
+
+ return media_pipeline_walk_push(walk, pad);
+}
+
+/* Explore the next link of the entity at the top of the stack. */
+static int media_pipeline_explore_next_link(struct media_pipeline *pipe,
+ struct media_pipeline_walk *walk)
+{
+ struct media_pipeline_walk_entry *entry = media_pipeline_walk_top(walk);
+ struct media_pad *pad;
+ struct media_link *link;
+ struct media_pad *local;
+ struct media_pad *remote;
+ int ret;
+
+ pad = entry->pad;
+ link = list_entry(entry->links, typeof(*link), list);
+ media_pipeline_walk_pop(walk);
+
+ dev_dbg(walk->mdev->dev,
+ "media pipeline: exploring link '%s':%u -> '%s':%u\n",
+ link->source->entity->name, link->source->index,
+ link->sink->entity->name, link->sink->index);
+
+ /* Skip links that are not enabled. */
+ if (!(link->flags & MEDIA_LNK_FL_ENABLED)) {
+ dev_dbg(walk->mdev->dev,
+ "media pipeline: skipping link (disabled)\n");
+ return 0;
+ }
+
+ /* Get the local pad and remote pad. */
+ if (link->source->entity == pad->entity) {
+ local = link->source;
+ remote = link->sink;
+ } else {
+ local = link->sink;
+ remote = link->source;
+ }
+
+ /*
+ * Skip links that originate from a different pad than the incoming pad
+ * that is not connected internally in the entity to the incoming pad.
+ */
+ if (pad != local &&
+ !media_entity_has_pad_interdep(pad->entity, pad->index, local->index)) {
+ dev_dbg(walk->mdev->dev,
+ "media pipeline: skipping link (no route)\n");
+ return 0;
+ }
+
+ /*
+ * Add the local and remote pads of the link to the pipeline and push
+ * them to the stack, if they're not already present.
+ */
+ ret = media_pipeline_add_pad(pipe, walk, local);
+ if (ret)
+ return ret;
+
+ ret = media_pipeline_add_pad(pipe, walk, remote);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static void media_pipeline_cleanup(struct media_pipeline *pipe)
+{
+ while (!list_empty(&pipe->pads)) {
+ struct media_pipeline_pad *ppad;
+
+ ppad = list_first_entry(&pipe->pads, typeof(*ppad), list);
+ list_del(&ppad->list);
+ kfree(ppad);
+ }
+}
+
+static int media_pipeline_populate(struct media_pipeline *pipe,
+ struct media_pad *pad)
+{
+ struct media_pipeline_walk walk = { };
+ struct media_pipeline_pad *ppad;
+ int ret;
+
+ /*
+ * Populate the media pipeline by walking the media graph, starting
+ * from @pad.
+ */
+ INIT_LIST_HEAD(&pipe->pads);
+ pipe->mdev = pad->graph_obj.mdev;
+
+ walk.mdev = pipe->mdev;
+ walk.stack.top = -1;
+ ret = media_pipeline_add_pad(pipe, &walk, pad);
+ if (ret)
+ goto done;
+
+ /*
+ * Use a depth-first search algorithm: as long as the stack is not
+ * empty, explore the next link of the top entry. The
+ * media_pipeline_explore_next_link() function will either move to the
+ * next link, pop the entry if fully visited, or add new entries on
+ * top.
+ */
+ while (!media_pipeline_walk_empty(&walk)) {
+ ret = media_pipeline_explore_next_link(pipe, &walk);
+ if (ret)
+ goto done;
+ }
+
+ dev_dbg(pad->graph_obj.mdev->dev,
+ "media pipeline populated, found pads:\n");
+
+ list_for_each_entry(ppad, &pipe->pads, list)
+ dev_dbg(pad->graph_obj.mdev->dev, "- '%s':%u\n",
+ ppad->pad->entity->name, ppad->pad->index);
+
+ WARN_ON(walk.stack.top != -1);
+
+ ret = 0;
+
+done:
+ media_pipeline_walk_destroy(&walk);
+
+ if (ret)
+ media_pipeline_cleanup(pipe);
+
+ return ret;
+}
+
+__must_check int __media_pipeline_start(struct media_pad *pad,
+ struct media_pipeline *pipe)
+{
+ struct media_device *mdev = pad->graph_obj.mdev;
+ struct media_pipeline_pad *err_ppad;
+ struct media_pipeline_pad *ppad;
+ int ret;
+
+ lockdep_assert_held(&mdev->graph_mutex);
+
+ /*
+ * If the pad is already part of a pipeline, that pipeline must be the
+ * same as the pipe given to media_pipeline_start().
+ */
+ if (WARN_ON(pad->pipe && pad->pipe != pipe))
+ return -EINVAL;
+
+ /*
+ * If the pipeline has already been started, it is guaranteed to be
+ * valid, so just increase the start count.
+ */
+ if (pipe->start_count) {
+ pipe->start_count++;
+ return 0;
+ }
+
+ /*
+ * Populate the pipeline. This populates the media_pipeline pads list
+ * with media_pipeline_pad instances for each pad found during graph
+ * walk.
+ */
+ ret = media_pipeline_populate(pipe, pad);
+ if (ret)
+ return ret;
+
+ /*
+ * Now that all the pads in the pipeline have been gathered, perform
+ * the validation steps.
+ */
+
+ list_for_each_entry(ppad, &pipe->pads, list) {
+ struct media_pad *pad = ppad->pad;
+ struct media_entity *entity = pad->entity;
+ bool has_enabled_link = false;
+ bool has_link = false;
+ struct media_link *link;
+
+ dev_dbg(mdev->dev, "Validating pad '%s':%u\n", pad->entity->name,
+ pad->index);
+
+ /*
+ * 1. Ensure that the pad doesn't already belong to a different
+ * pipeline.
+ */
+ if (pad->pipe) {
+ dev_dbg(mdev->dev, "Failed to start pipeline: pad '%s':%u busy\n",
+ pad->entity->name, pad->index);
+ ret = -EBUSY;
+ goto error;
+ }
+
+ /*
+ * 2. Validate all active links whose sink is the current pad.
+ * Validation of the source pads is performed in the context of
+ * the connected sink pad to avoid duplicating checks.
+ */
+ for_each_media_entity_data_link(entity, link) {
+ /* Skip links unrelated to the current pad. */
+ if (link->sink != pad && link->source != pad)
+ continue;
+
+ /* Record if the pad has links and enabled links. */
+ if (link->flags & MEDIA_LNK_FL_ENABLED)
+ has_enabled_link = true;
+ has_link = true;
+
+ /*
+ * Validate the link if it's enabled and has the
+ * current pad as its sink.
+ */
+ if (!(link->flags & MEDIA_LNK_FL_ENABLED))
+ continue;
+
+ if (link->sink != pad)
+ continue;
+
+ if (!entity->ops || !entity->ops->link_validate)
+ continue;
+
+ ret = entity->ops->link_validate(link);
+ if (ret) {
+ dev_dbg(mdev->dev,
+ "Link '%s':%u -> '%s':%u failed validation: %d\n",
+ link->source->entity->name,
+ link->source->index,
+ link->sink->entity->name,
+ link->sink->index, ret);
+ goto error;
+ }
+
+ dev_dbg(mdev->dev,
+ "Link '%s':%u -> '%s':%u is valid\n",
+ link->source->entity->name,
+ link->source->index,
+ link->sink->entity->name,
+ link->sink->index);
+ }
+
+ /*
+ * 3. If the pad has the MEDIA_PAD_FL_MUST_CONNECT flag set,
+ * ensure that it has either no link or an enabled link.
+ */
+ if ((pad->flags & MEDIA_PAD_FL_MUST_CONNECT) && has_link &&
+ !has_enabled_link) {
+ dev_dbg(mdev->dev,
+ "Pad '%s':%u must be connected by an enabled link\n",
+ pad->entity->name, pad->index);
+ ret = -ENOLINK;
+ goto error;
+ }
+
+ /* Validation passed, store the pipe pointer in the pad. */
+ pad->pipe = pipe;
+ }
+
+ pipe->start_count++;
+
+ return 0;
+
+error:
+ /*
+ * Link validation on graph failed. We revert what we did and
+ * return the error.
+ */
+
+ list_for_each_entry(err_ppad, &pipe->pads, list) {
+ if (err_ppad == ppad)
+ break;
+
+ err_ppad->pad->pipe = NULL;
+ }
+
+ media_pipeline_cleanup(pipe);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(__media_pipeline_start);
+
+__must_check int media_pipeline_start(struct media_pad *pad,
+ struct media_pipeline *pipe)
+{
+ struct media_device *mdev = pad->graph_obj.mdev;
+ int ret;
+
+ mutex_lock(&mdev->graph_mutex);
+ ret = __media_pipeline_start(pad, pipe);
+ mutex_unlock(&mdev->graph_mutex);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(media_pipeline_start);
+
+void __media_pipeline_stop(struct media_pad *pad)
+{
+ struct media_pipeline *pipe = pad->pipe;
+ struct media_pipeline_pad *ppad;
+
+ /*
+ * If the following check fails, the driver has performed an
+ * unbalanced call to media_pipeline_stop()
+ */
+ if (WARN_ON(!pipe))
+ return;
+
+ if (--pipe->start_count)
+ return;
+
+ list_for_each_entry(ppad, &pipe->pads, list)
+ ppad->pad->pipe = NULL;
+
+ media_pipeline_cleanup(pipe);
+
+ if (pipe->allocated)
+ kfree(pipe);
+}
+EXPORT_SYMBOL_GPL(__media_pipeline_stop);
+
+void media_pipeline_stop(struct media_pad *pad)
+{
+ struct media_device *mdev = pad->graph_obj.mdev;
+
+ mutex_lock(&mdev->graph_mutex);
+ __media_pipeline_stop(pad);
+ mutex_unlock(&mdev->graph_mutex);
+}
+EXPORT_SYMBOL_GPL(media_pipeline_stop);
+
+__must_check int media_pipeline_alloc_start(struct media_pad *pad)
+{
+ struct media_device *mdev = pad->graph_obj.mdev;
+ struct media_pipeline *new_pipe = NULL;
+ struct media_pipeline *pipe;
+ int ret;
+
+ mutex_lock(&mdev->graph_mutex);
+
+ /*
+ * Is the pad already part of a pipeline? If not, we need to allocate
+ * a pipe.
+ */
+ pipe = media_pad_pipeline(pad);
+ if (!pipe) {
+ new_pipe = kzalloc(sizeof(*new_pipe), GFP_KERNEL);
+ if (!new_pipe) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ pipe = new_pipe;
+ pipe->allocated = true;
+ }
+
+ ret = __media_pipeline_start(pad, pipe);
+ if (ret)
+ kfree(new_pipe);
+
+out:
+ mutex_unlock(&mdev->graph_mutex);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(media_pipeline_alloc_start);
+
+struct media_pad *
+__media_pipeline_pad_iter_next(struct media_pipeline *pipe,
+ struct media_pipeline_pad_iter *iter,
+ struct media_pad *pad)
+{
+ if (!pad)
+ iter->cursor = pipe->pads.next;
+
+ if (iter->cursor == &pipe->pads)
+ return NULL;
+
+ pad = list_entry(iter->cursor, struct media_pipeline_pad, list)->pad;
+ iter->cursor = iter->cursor->next;
+
+ return pad;
+}
+EXPORT_SYMBOL_GPL(__media_pipeline_pad_iter_next);
+
+int media_pipeline_entity_iter_init(struct media_pipeline *pipe,
+ struct media_pipeline_entity_iter *iter)
+{
+ return media_entity_enum_init(&iter->ent_enum, pipe->mdev);
+}
+EXPORT_SYMBOL_GPL(media_pipeline_entity_iter_init);
+
+void media_pipeline_entity_iter_cleanup(struct media_pipeline_entity_iter *iter)
+{
+ media_entity_enum_cleanup(&iter->ent_enum);
+}
+EXPORT_SYMBOL_GPL(media_pipeline_entity_iter_cleanup);
+
+struct media_entity *
+__media_pipeline_entity_iter_next(struct media_pipeline *pipe,
+ struct media_pipeline_entity_iter *iter,
+ struct media_entity *entity)
+{
+ if (!entity)
+ iter->cursor = pipe->pads.next;
+
+ while (iter->cursor != &pipe->pads) {
+ struct media_pipeline_pad *ppad;
+ struct media_entity *entity;
+
+ ppad = list_entry(iter->cursor, struct media_pipeline_pad, list);
+ entity = ppad->pad->entity;
+ iter->cursor = iter->cursor->next;
+
+ if (!media_entity_enum_test_and_set(&iter->ent_enum, entity))
+ return entity;
+ }
+
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(__media_pipeline_entity_iter_next);
+
+/* -----------------------------------------------------------------------------
+ * Links management
+ */
+
+static struct media_link *media_add_link(struct list_head *head)
+{
+ struct media_link *link;
+
+ link = kzalloc(sizeof(*link), GFP_KERNEL);
+ if (link == NULL)
+ return NULL;
+
+ list_add_tail(&link->list, head);
+
+ return link;
+}
+
+static void __media_entity_remove_link(struct media_entity *entity,
+ struct media_link *link)
+{
+ struct media_link *rlink, *tmp;
+ struct media_entity *remote;
+
+ /* Remove the reverse links for a data link. */
+ if ((link->flags & MEDIA_LNK_FL_LINK_TYPE) == MEDIA_LNK_FL_DATA_LINK) {
+ if (link->source->entity == entity)
+ remote = link->sink->entity;
+ else
+ remote = link->source->entity;
+
+ list_for_each_entry_safe(rlink, tmp, &remote->links, list) {
+ if (rlink != link->reverse)
+ continue;
+
+ if (link->source->entity == entity)
+ remote->num_backlinks--;
+
+ /* Remove the remote link */
+ list_del(&rlink->list);
+ media_gobj_destroy(&rlink->graph_obj);
+ kfree(rlink);
+
+ if (--remote->num_links == 0)
+ break;
+ }
+ }
+
+ list_del(&link->list);
+ media_gobj_destroy(&link->graph_obj);
+ kfree(link);
+}
+
+int media_get_pad_index(struct media_entity *entity, u32 pad_type,
+ enum media_pad_signal_type sig_type)
+{
+ unsigned int i;
+
+ if (!entity)
+ return -EINVAL;
+
+ for (i = 0; i < entity->num_pads; i++) {
+ if ((entity->pads[i].flags &
+ (MEDIA_PAD_FL_SINK | MEDIA_PAD_FL_SOURCE)) != pad_type)
+ continue;
+
+ if (entity->pads[i].sig_type == sig_type)
+ return i;
+ }
+ return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(media_get_pad_index);
+
+int
+media_create_pad_link(struct media_entity *source, u16 source_pad,
+ struct media_entity *sink, u16 sink_pad, u32 flags)
+{
+ struct media_link *link;
+ struct media_link *backlink;
+
+ if (WARN_ON(!source || !sink) ||
+ WARN_ON(source_pad >= source->num_pads) ||
+ WARN_ON(sink_pad >= sink->num_pads))
+ return -EINVAL;
+ if (WARN_ON(!(source->pads[source_pad].flags & MEDIA_PAD_FL_SOURCE)))
+ return -EINVAL;
+ if (WARN_ON(!(sink->pads[sink_pad].flags & MEDIA_PAD_FL_SINK)))
+ return -EINVAL;
+
+ link = media_add_link(&source->links);
+ if (link == NULL)
+ return -ENOMEM;
+
+ link->source = &source->pads[source_pad];
+ link->sink = &sink->pads[sink_pad];
+ link->flags = flags & ~MEDIA_LNK_FL_INTERFACE_LINK;
+
+ /* Initialize graph object embedded at the new link */
+ media_gobj_create(source->graph_obj.mdev, MEDIA_GRAPH_LINK,
+ &link->graph_obj);
+
+ /* Create the backlink. Backlinks are used to help graph traversal and
+ * are not reported to userspace.
+ */
+ backlink = media_add_link(&sink->links);
+ if (backlink == NULL) {
+ __media_entity_remove_link(source, link);
+ return -ENOMEM;
+ }
+
+ backlink->source = &source->pads[source_pad];
+ backlink->sink = &sink->pads[sink_pad];
+ backlink->flags = flags;
+ backlink->is_backlink = true;
+
+ /* Initialize graph object embedded at the new link */
+ media_gobj_create(sink->graph_obj.mdev, MEDIA_GRAPH_LINK,
+ &backlink->graph_obj);
+
+ link->reverse = backlink;
+ backlink->reverse = link;
+
+ sink->num_backlinks++;
+ sink->num_links++;
+ source->num_links++;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(media_create_pad_link);
+
+int media_create_pad_links(const struct media_device *mdev,
+ const u32 source_function,
+ struct media_entity *source,
+ const u16 source_pad,
+ const u32 sink_function,
+ struct media_entity *sink,
+ const u16 sink_pad,
+ u32 flags,
+ const bool allow_both_undefined)
+{
+ struct media_entity *entity;
+ unsigned function;
+ int ret;
+
+ /* Trivial case: 1:1 relation */
+ if (source && sink)
+ return media_create_pad_link(source, source_pad,
+ sink, sink_pad, flags);
+
+ /* Worse case scenario: n:n relation */
+ if (!source && !sink) {
+ if (!allow_both_undefined)
+ return 0;
+ media_device_for_each_entity(source, mdev) {
+ if (source->function != source_function)
+ continue;
+ media_device_for_each_entity(sink, mdev) {
+ if (sink->function != sink_function)
+ continue;
+ ret = media_create_pad_link(source, source_pad,
+ sink, sink_pad,
+ flags);
+ if (ret)
+ return ret;
+ flags &= ~(MEDIA_LNK_FL_ENABLED |
+ MEDIA_LNK_FL_IMMUTABLE);
+ }
+ }
+ return 0;
+ }
+
+ /* Handle 1:n and n:1 cases */
+ if (source)
+ function = sink_function;
+ else
+ function = source_function;
+
+ media_device_for_each_entity(entity, mdev) {
+ if (entity->function != function)
+ continue;
+
+ if (source)
+ ret = media_create_pad_link(source, source_pad,
+ entity, sink_pad, flags);
+ else
+ ret = media_create_pad_link(entity, source_pad,
+ sink, sink_pad, flags);
+ if (ret)
+ return ret;
+ flags &= ~(MEDIA_LNK_FL_ENABLED | MEDIA_LNK_FL_IMMUTABLE);
+ }
+ return 0;
+}
+EXPORT_SYMBOL_GPL(media_create_pad_links);
+
+void __media_entity_remove_links(struct media_entity *entity)
+{
+ struct media_link *link, *tmp;
+
+ list_for_each_entry_safe(link, tmp, &entity->links, list)
+ __media_entity_remove_link(entity, link);
+
+ entity->num_links = 0;
+ entity->num_backlinks = 0;
+}
+EXPORT_SYMBOL_GPL(__media_entity_remove_links);
+
+void media_entity_remove_links(struct media_entity *entity)
+{
+ struct media_device *mdev = entity->graph_obj.mdev;
+
+ /* Do nothing if the entity is not registered. */
+ if (mdev == NULL)
+ return;
+
+ mutex_lock(&mdev->graph_mutex);
+ __media_entity_remove_links(entity);
+ mutex_unlock(&mdev->graph_mutex);
+}
+EXPORT_SYMBOL_GPL(media_entity_remove_links);
+
+static int __media_entity_setup_link_notify(struct media_link *link, u32 flags)
+{
+ int ret;
+
+ /* Notify both entities. */
+ ret = media_entity_call(link->source->entity, link_setup,
+ link->source, link->sink, flags);
+ if (ret < 0 && ret != -ENOIOCTLCMD)
+ return ret;
+
+ ret = media_entity_call(link->sink->entity, link_setup,
+ link->sink, link->source, flags);
+ if (ret < 0 && ret != -ENOIOCTLCMD) {
+ media_entity_call(link->source->entity, link_setup,
+ link->source, link->sink, link->flags);
+ return ret;
+ }
+
+ link->flags = flags;
+ link->reverse->flags = link->flags;
+
+ return 0;
+}
+
+int __media_entity_setup_link(struct media_link *link, u32 flags)
+{
+ const u32 mask = MEDIA_LNK_FL_ENABLED;
+ struct media_device *mdev;
+ struct media_pad *source, *sink;
+ int ret = -EBUSY;
+
+ if (link == NULL)
+ return -EINVAL;
+
+ /* The non-modifiable link flags must not be modified. */
+ if ((link->flags & ~mask) != (flags & ~mask))
+ return -EINVAL;
+
+ if (link->flags & MEDIA_LNK_FL_IMMUTABLE)
+ return link->flags == flags ? 0 : -EINVAL;
+
+ if (link->flags == flags)
+ return 0;
+
+ source = link->source;
+ sink = link->sink;
+
+ if (!(link->flags & MEDIA_LNK_FL_DYNAMIC) &&
+ (media_pad_is_streaming(source) || media_pad_is_streaming(sink)))
+ return -EBUSY;
+
+ mdev = source->graph_obj.mdev;
+
+ if (mdev->ops && mdev->ops->link_notify) {
+ ret = mdev->ops->link_notify(link, flags,
+ MEDIA_DEV_NOTIFY_PRE_LINK_CH);
+ if (ret < 0)
+ return ret;
+ }
+
+ ret = __media_entity_setup_link_notify(link, flags);
+
+ if (mdev->ops && mdev->ops->link_notify)
+ mdev->ops->link_notify(link, flags,
+ MEDIA_DEV_NOTIFY_POST_LINK_CH);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(__media_entity_setup_link);
+
+int media_entity_setup_link(struct media_link *link, u32 flags)
+{
+ int ret;
+
+ mutex_lock(&link->graph_obj.mdev->graph_mutex);
+ ret = __media_entity_setup_link(link, flags);
+ mutex_unlock(&link->graph_obj.mdev->graph_mutex);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(media_entity_setup_link);
+
+struct media_link *
+media_entity_find_link(struct media_pad *source, struct media_pad *sink)
+{
+ struct media_link *link;
+
+ for_each_media_entity_data_link(source->entity, link) {
+ if (link->source->entity == source->entity &&
+ link->source->index == source->index &&
+ link->sink->entity == sink->entity &&
+ link->sink->index == sink->index)
+ return link;
+ }
+
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(media_entity_find_link);
+
+struct media_pad *media_pad_remote_pad_first(const struct media_pad *pad)
+{
+ struct media_link *link;
+
+ for_each_media_entity_data_link(pad->entity, link) {
+ if (!(link->flags & MEDIA_LNK_FL_ENABLED))
+ continue;
+
+ if (link->source == pad)
+ return link->sink;
+
+ if (link->sink == pad)
+ return link->source;
+ }
+
+ return NULL;
+
+}
+EXPORT_SYMBOL_GPL(media_pad_remote_pad_first);
+
+struct media_pad *
+media_entity_remote_pad_unique(const struct media_entity *entity,
+ unsigned int type)
+{
+ struct media_pad *pad = NULL;
+ struct media_link *link;
+
+ list_for_each_entry(link, &entity->links, list) {
+ struct media_pad *local_pad;
+ struct media_pad *remote_pad;
+
+ if (((link->flags & MEDIA_LNK_FL_LINK_TYPE) !=
+ MEDIA_LNK_FL_DATA_LINK) ||
+ !(link->flags & MEDIA_LNK_FL_ENABLED))
+ continue;
+
+ if (type == MEDIA_PAD_FL_SOURCE) {
+ local_pad = link->sink;
+ remote_pad = link->source;
+ } else {
+ local_pad = link->source;
+ remote_pad = link->sink;
+ }
+
+ if (local_pad->entity == entity) {
+ if (pad)
+ return ERR_PTR(-ENOTUNIQ);
+
+ pad = remote_pad;
+ }
+ }
+
+ if (!pad)
+ return ERR_PTR(-ENOLINK);
+
+ return pad;
+}
+EXPORT_SYMBOL_GPL(media_entity_remote_pad_unique);
+
+struct media_pad *media_pad_remote_pad_unique(const struct media_pad *pad)
+{
+ struct media_pad *found_pad = NULL;
+ struct media_link *link;
+
+ list_for_each_entry(link, &pad->entity->links, list) {
+ struct media_pad *remote_pad;
+
+ if (!(link->flags & MEDIA_LNK_FL_ENABLED))
+ continue;
+
+ if (link->sink == pad)
+ remote_pad = link->source;
+ else if (link->source == pad)
+ remote_pad = link->sink;
+ else
+ continue;
+
+ if (found_pad)
+ return ERR_PTR(-ENOTUNIQ);
+
+ found_pad = remote_pad;
+ }
+
+ if (!found_pad)
+ return ERR_PTR(-ENOLINK);
+
+ return found_pad;
+}
+EXPORT_SYMBOL_GPL(media_pad_remote_pad_unique);
+
+int media_entity_get_fwnode_pad(struct media_entity *entity,
+ const struct fwnode_handle *fwnode,
+ unsigned long direction_flags)
+{
+ struct fwnode_endpoint endpoint;
+ unsigned int i;
+ int ret;
+
+ if (!entity->ops || !entity->ops->get_fwnode_pad) {
+ for (i = 0; i < entity->num_pads; i++) {
+ if (entity->pads[i].flags & direction_flags)
+ return i;
+ }
+
+ return -ENXIO;
+ }
+
+ ret = fwnode_graph_parse_endpoint(fwnode, &endpoint);
+ if (ret)
+ return ret;
+
+ ret = entity->ops->get_fwnode_pad(entity, &endpoint);
+ if (ret < 0)
+ return ret;
+
+ if (ret >= entity->num_pads)
+ return -ENXIO;
+
+ if (!(entity->pads[ret].flags & direction_flags))
+ return -ENXIO;
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(media_entity_get_fwnode_pad);
+
+struct media_pipeline *media_entity_pipeline(struct media_entity *entity)
+{
+ struct media_pad *pad;
+
+ media_entity_for_each_pad(entity, pad) {
+ if (pad->pipe)
+ return pad->pipe;
+ }
+
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(media_entity_pipeline);
+
+struct media_pipeline *media_pad_pipeline(struct media_pad *pad)
+{
+ return pad->pipe;
+}
+EXPORT_SYMBOL_GPL(media_pad_pipeline);
+
+static void media_interface_init(struct media_device *mdev,
+ struct media_interface *intf,
+ u32 gobj_type,
+ u32 intf_type, u32 flags)
+{
+ intf->type = intf_type;
+ intf->flags = flags;
+ INIT_LIST_HEAD(&intf->links);
+
+ media_gobj_create(mdev, gobj_type, &intf->graph_obj);
+}
+
+/* Functions related to the media interface via device nodes */
+
+struct media_intf_devnode *media_devnode_create(struct media_device *mdev,
+ u32 type, u32 flags,
+ u32 major, u32 minor)
+{
+ struct media_intf_devnode *devnode;
+
+ devnode = kzalloc(sizeof(*devnode), GFP_KERNEL);
+ if (!devnode)
+ return NULL;
+
+ devnode->major = major;
+ devnode->minor = minor;
+
+ media_interface_init(mdev, &devnode->intf, MEDIA_GRAPH_INTF_DEVNODE,
+ type, flags);
+
+ return devnode;
+}
+EXPORT_SYMBOL_GPL(media_devnode_create);
+
+void media_devnode_remove(struct media_intf_devnode *devnode)
+{
+ media_remove_intf_links(&devnode->intf);
+ media_gobj_destroy(&devnode->intf.graph_obj);
+ kfree(devnode);
+}
+EXPORT_SYMBOL_GPL(media_devnode_remove);
+
+struct media_link *media_create_intf_link(struct media_entity *entity,
+ struct media_interface *intf,
+ u32 flags)
+{
+ struct media_link *link;
+
+ link = media_add_link(&intf->links);
+ if (link == NULL)
+ return NULL;
+
+ link->intf = intf;
+ link->entity = entity;
+ link->flags = flags | MEDIA_LNK_FL_INTERFACE_LINK;
+
+ /* Initialize graph object embedded at the new link */
+ media_gobj_create(intf->graph_obj.mdev, MEDIA_GRAPH_LINK,
+ &link->graph_obj);
+
+ return link;
+}
+EXPORT_SYMBOL_GPL(media_create_intf_link);
+
+void __media_remove_intf_link(struct media_link *link)
+{
+ list_del(&link->list);
+ media_gobj_destroy(&link->graph_obj);
+ kfree(link);
+}
+EXPORT_SYMBOL_GPL(__media_remove_intf_link);
+
+void media_remove_intf_link(struct media_link *link)
+{
+ struct media_device *mdev = link->graph_obj.mdev;
+
+ /* Do nothing if the intf is not registered. */
+ if (mdev == NULL)
+ return;
+
+ mutex_lock(&mdev->graph_mutex);
+ __media_remove_intf_link(link);
+ mutex_unlock(&mdev->graph_mutex);
+}
+EXPORT_SYMBOL_GPL(media_remove_intf_link);
+
+void __media_remove_intf_links(struct media_interface *intf)
+{
+ struct media_link *link, *tmp;
+
+ list_for_each_entry_safe(link, tmp, &intf->links, list)
+ __media_remove_intf_link(link);
+
+}
+EXPORT_SYMBOL_GPL(__media_remove_intf_links);
+
+void media_remove_intf_links(struct media_interface *intf)
+{
+ struct media_device *mdev = intf->graph_obj.mdev;
+
+ /* Do nothing if the intf is not registered. */
+ if (mdev == NULL)
+ return;
+
+ mutex_lock(&mdev->graph_mutex);
+ __media_remove_intf_links(intf);
+ mutex_unlock(&mdev->graph_mutex);
+}
+EXPORT_SYMBOL_GPL(media_remove_intf_links);
+
+struct media_link *media_create_ancillary_link(struct media_entity *primary,
+ struct media_entity *ancillary)
+{
+ struct media_link *link;
+
+ link = media_add_link(&primary->links);
+ if (!link)
+ return ERR_PTR(-ENOMEM);
+
+ link->gobj0 = &primary->graph_obj;
+ link->gobj1 = &ancillary->graph_obj;
+ link->flags = MEDIA_LNK_FL_IMMUTABLE | MEDIA_LNK_FL_ENABLED |
+ MEDIA_LNK_FL_ANCILLARY_LINK;
+
+ /* Initialize graph object embedded in the new link */
+ media_gobj_create(primary->graph_obj.mdev, MEDIA_GRAPH_LINK,
+ &link->graph_obj);
+
+ return link;
+}
+EXPORT_SYMBOL_GPL(media_create_ancillary_link);
+
+struct media_link *__media_entity_next_link(struct media_entity *entity,
+ struct media_link *link,
+ unsigned long link_type)
+{
+ link = link ? list_next_entry(link, list)
+ : list_first_entry(&entity->links, typeof(*link), list);
+
+ list_for_each_entry_from(link, &entity->links, list)
+ if ((link->flags & MEDIA_LNK_FL_LINK_TYPE) == link_type)
+ return link;
+
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(__media_entity_next_link);