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path: root/drivers/media/mc/mc-entity.c
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Diffstat (limited to 'drivers/media/mc/mc-entity.c')
-rw-r--r--drivers/media/mc/mc-entity.c1036
1 files changed, 1036 insertions, 0 deletions
diff --git a/drivers/media/mc/mc-entity.c b/drivers/media/mc/mc-entity.c
new file mode 100644
index 000000000000..a998a2e0ea1d
--- /dev/null
+++ b/drivers/media/mc/mc-entity.c
@@ -0,0 +1,1036 @@
+/*
+ * Media entity
+ *
+ * Copyright (C) 2010 Nokia Corporation
+ *
+ * Contacts: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+ * Sakari Ailus <sakari.ailus@iki.fi>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/bitmap.h>
+#include <linux/property.h>
+#include <linux/slab.h>
+#include <media/media-entity.h>
+#include <media/media-device.h>
+
+static inline const char *gobj_type(enum media_gobj_type type)
+{
+ switch (type) {
+ case MEDIA_GRAPH_ENTITY:
+ return "entity";
+ case MEDIA_GRAPH_PAD:
+ return "pad";
+ case MEDIA_GRAPH_LINK:
+ return "link";
+ case MEDIA_GRAPH_INTF_DEVNODE:
+ return "intf-devnode";
+ default:
+ return "unknown";
+ }
+}
+
+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";
+ }
+};
+
+__must_check int __media_entity_enum_init(struct media_entity_enum *ent_enum,
+ int idx_max)
+{
+ idx_max = ALIGN(idx_max, BITS_PER_LONG);
+ ent_enum->bmap = kcalloc(idx_max / BITS_PER_LONG, sizeof(long),
+ GFP_KERNEL);
+ if (!ent_enum->bmap)
+ return -ENOMEM;
+
+ bitmap_zero(ent_enum->bmap, idx_max);
+ 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)
+{
+ kfree(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),
+ media_type(link->gobj0) == MEDIA_GRAPH_PAD ?
+ "data" : "interface",
+ 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;
+ unsigned int i;
+
+ if (num_pads >= MEDIA_ENTITY_MAX_PADS)
+ return -E2BIG;
+
+ entity->num_pads = num_pads;
+ entity->pads = pads;
+
+ if (mdev)
+ mutex_lock(&mdev->graph_mutex);
+
+ for (i = 0; i < num_pads; i++) {
+ pads[i].entity = entity;
+ pads[i].index = i;
+ if (mdev)
+ media_gobj_create(mdev, MEDIA_GRAPH_PAD,
+ &entity->pads[i].graph_obj);
+ }
+
+ if (mdev)
+ mutex_unlock(&mdev->graph_mutex);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(media_entity_pads_init);
+
+/* -----------------------------------------------------------------------------
+ * Graph traversal
+ */
+
+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_free().
+ *
+ * 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);
+
+ /* 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 in 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);
+}
+
+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);
+
+int media_entity_get_fwnode_pad(struct media_entity *entity,
+ 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(&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);
+
+/* -----------------------------------------------------------------------------
+ * Pipeline management
+ */
+
+__must_check int __media_pipeline_start(struct media_entity *entity,
+ struct media_pipeline *pipe)
+{
+ struct media_device *mdev = entity->graph_obj.mdev;
+ struct media_graph *graph = &pipe->graph;
+ struct media_entity *entity_err = entity;
+ struct media_link *link;
+ int ret;
+
+ if (!pipe->streaming_count++) {
+ ret = media_graph_walk_init(&pipe->graph, mdev);
+ if (ret)
+ goto error_graph_walk_start;
+ }
+
+ media_graph_walk_start(&pipe->graph, entity);
+
+ while ((entity = media_graph_walk_next(graph))) {
+ DECLARE_BITMAP(active, MEDIA_ENTITY_MAX_PADS);
+ DECLARE_BITMAP(has_no_links, MEDIA_ENTITY_MAX_PADS);
+
+ entity->stream_count++;
+
+ if (entity->pipe && entity->pipe != pipe) {
+ pr_err("Pipe active for %s. Can't start for %s\n",
+ entity->name,
+ entity_err->name);
+ ret = -EBUSY;
+ goto error;
+ }
+
+ entity->pipe = pipe;
+
+ /* Already streaming --- no need to check. */
+ if (entity->stream_count > 1)
+ continue;
+
+ if (!entity->ops || !entity->ops->link_validate)
+ continue;
+
+ bitmap_zero(active, entity->num_pads);
+ bitmap_fill(has_no_links, entity->num_pads);
+
+ list_for_each_entry(link, &entity->links, list) {
+ struct media_pad *pad = link->sink->entity == entity
+ ? link->sink : link->source;
+
+ /* Mark that a pad is connected by a link. */
+ bitmap_clear(has_no_links, pad->index, 1);
+
+ /*
+ * Pads that either do not need to connect or
+ * are connected through an enabled link are
+ * fine.
+ */
+ if (!(pad->flags & MEDIA_PAD_FL_MUST_CONNECT) ||
+ link->flags & MEDIA_LNK_FL_ENABLED)
+ bitmap_set(active, pad->index, 1);
+
+ /*
+ * Link validation will only take place for
+ * sink ends of the link that are enabled.
+ */
+ if (link->sink != pad ||
+ !(link->flags & MEDIA_LNK_FL_ENABLED))
+ continue;
+
+ ret = entity->ops->link_validate(link);
+ if (ret < 0 && ret != -ENOIOCTLCMD) {
+ dev_dbg(entity->graph_obj.mdev->dev,
+ "link validation failed for '%s':%u -> '%s':%u, error %d\n",
+ link->source->entity->name,
+ link->source->index,
+ entity->name, link->sink->index, ret);
+ goto error;
+ }
+ }
+
+ /* Either no links or validated links are fine. */
+ bitmap_or(active, active, has_no_links, entity->num_pads);
+
+ if (!bitmap_full(active, entity->num_pads)) {
+ ret = -ENOLINK;
+ dev_dbg(entity->graph_obj.mdev->dev,
+ "'%s':%u must be connected by an enabled link\n",
+ entity->name,
+ (unsigned)find_first_zero_bit(
+ active, entity->num_pads));
+ goto error;
+ }
+ }
+
+ return 0;
+
+error:
+ /*
+ * Link validation on graph failed. We revert what we did and
+ * return the error.
+ */
+ media_graph_walk_start(graph, entity_err);
+
+ while ((entity_err = media_graph_walk_next(graph))) {
+ /* Sanity check for negative stream_count */
+ if (!WARN_ON_ONCE(entity_err->stream_count <= 0)) {
+ entity_err->stream_count--;
+ if (entity_err->stream_count == 0)
+ entity_err->pipe = NULL;
+ }
+
+ /*
+ * We haven't increased stream_count further than this
+ * so we quit here.
+ */
+ if (entity_err == entity)
+ break;
+ }
+
+error_graph_walk_start:
+ if (!--pipe->streaming_count)
+ media_graph_walk_cleanup(graph);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(__media_pipeline_start);
+
+__must_check int media_pipeline_start(struct media_entity *entity,
+ struct media_pipeline *pipe)
+{
+ struct media_device *mdev = entity->graph_obj.mdev;
+ int ret;
+
+ mutex_lock(&mdev->graph_mutex);
+ ret = __media_pipeline_start(entity, pipe);
+ mutex_unlock(&mdev->graph_mutex);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(media_pipeline_start);
+
+void __media_pipeline_stop(struct media_entity *entity)
+{
+ struct media_graph *graph = &entity->pipe->graph;
+ struct media_pipeline *pipe = entity->pipe;
+
+ /*
+ * If the following check fails, the driver has performed an
+ * unbalanced call to media_pipeline_stop()
+ */
+ if (WARN_ON(!pipe))
+ return;
+
+ media_graph_walk_start(graph, entity);
+
+ while ((entity = media_graph_walk_next(graph))) {
+ /* Sanity check for negative stream_count */
+ if (!WARN_ON_ONCE(entity->stream_count <= 0)) {
+ entity->stream_count--;
+ if (entity->stream_count == 0)
+ entity->pipe = NULL;
+ }
+ }
+
+ if (!--pipe->streaming_count)
+ media_graph_walk_cleanup(graph);
+
+}
+EXPORT_SYMBOL_GPL(__media_pipeline_stop);
+
+void media_pipeline_stop(struct media_entity *entity)
+{
+ struct media_device *mdev = entity->graph_obj.mdev;
+
+ mutex_lock(&mdev->graph_mutex);
+ __media_pipeline_stop(entity);
+ mutex_unlock(&mdev->graph_mutex);
+}
+EXPORT_SYMBOL_GPL(media_pipeline_stop);
+
+/* -----------------------------------------------------------------------------
+ * 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;
+
+ 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, bool is_sink,
+ enum media_pad_signal_type sig_type)
+{
+ int i;
+ bool pad_is_sink;
+
+ if (!entity)
+ return -EINVAL;
+
+ for (i = 0; i < entity->num_pads; i++) {
+ if (entity->pads[i].flags == MEDIA_PAD_FL_SINK)
+ pad_is_sink = true;
+ else if (entity->pads[i].flags == MEDIA_PAD_FL_SOURCE)
+ pad_is_sink = false;
+ else
+ continue; /* This is an error! */
+
+ if (pad_is_sink != is_sink)
+ 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;
+
+ BUG_ON(source == NULL || sink == NULL);
+ BUG_ON(source_pad >= source->num_pads);
+ BUG_ON(sink_pad >= sink->num_pads);
+
+ 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_entity *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->entity;
+ sink = link->sink->entity;
+
+ if (!(link->flags & MEDIA_LNK_FL_DYNAMIC) &&
+ (source->stream_count || sink->stream_count))
+ 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;
+
+ list_for_each_entry(link, &source->entity->links, list) {
+ 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_entity_remote_pad(const struct media_pad *pad)
+{
+ struct media_link *link;
+
+ list_for_each_entry(link, &pad->entity->links, list) {
+ 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_entity_remote_pad);
+
+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);