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authorLaurent Pinchart <laurent.pinchart@ideasonboard.com>2009-12-09 14:40:03 +0300
committerMauro Carvalho Chehab <mchehab@redhat.com>2011-03-22 10:53:16 +0300
commit97548ed4c4661502cdfd1aabd5d3876fa4f5cc2e (patch)
treec85b85954f53e3a97b6590de8d5d5396e7c43358 /drivers/media/media-entity.c
parent1651333b09743887bc2dd3d158a11853a2be3fe7 (diff)
downloadlinux-97548ed4c4661502cdfd1aabd5d3876fa4f5cc2e.tar.xz
[media] media: Links setup
Create the following ioctl and implement it at the media device level to setup links. - MEDIA_IOC_SETUP_LINK: Modify the properties of a given link The only property that can currently be modified is the ENABLED link flag to enable/disable a link. Links marked with the IMMUTABLE link flag can not be enabled or disabled. Enabling or disabling a link has effects on entities' use count. Those changes are automatically propagated through the graph. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Stanimir Varbanov <svarbanov@mm-sol.com> Signed-off-by: Sakari Ailus <sakari.ailus@iki.fi> Acked-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Diffstat (limited to 'drivers/media/media-entity.c')
-rw-r--r--drivers/media/media-entity.c155
1 files changed, 155 insertions, 0 deletions
diff --git a/drivers/media/media-entity.c b/drivers/media/media-entity.c
index 3e7e2d569cec..6795c920d460 100644
--- a/drivers/media/media-entity.c
+++ b/drivers/media/media-entity.c
@@ -306,3 +306,158 @@ media_entity_create_link(struct media_entity *source, u16 source_pad,
return 0;
}
EXPORT_SYMBOL_GPL(media_entity_create_link);
+
+static int __media_entity_setup_link_notify(struct media_link *link, u32 flags)
+{
+ const u32 mask = MEDIA_LNK_FL_ENABLED;
+ 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 = (link->flags & ~mask) | (flags & mask);
+ link->reverse->flags = link->flags;
+
+ return 0;
+}
+
+/**
+ * __media_entity_setup_link - Configure a media link
+ * @link: The link being configured
+ * @flags: Link configuration flags
+ *
+ * The bulk of link setup is handled by the two entities connected through the
+ * link. This function notifies both entities of the link configuration change.
+ *
+ * If the link is immutable or if the current and new configuration are
+ * identical, return immediately.
+ *
+ * The user is expected to hold link->source->parent->mutex. If not,
+ * media_entity_setup_link() should be used instead.
+ */
+int __media_entity_setup_link(struct media_link *link, u32 flags)
+{
+ struct media_device *mdev;
+ struct media_entity *source, *sink;
+ int ret = -EBUSY;
+
+ if (link == NULL)
+ 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;
+
+ mdev = source->parent;
+
+ if ((flags & MEDIA_LNK_FL_ENABLED) && mdev->link_notify) {
+ ret = mdev->link_notify(link->source, link->sink,
+ MEDIA_LNK_FL_ENABLED);
+ if (ret < 0)
+ return ret;
+ }
+
+ ret = __media_entity_setup_link_notify(link, flags);
+ if (ret < 0)
+ goto err;
+
+ if (!(flags & MEDIA_LNK_FL_ENABLED) && mdev->link_notify)
+ mdev->link_notify(link->source, link->sink, 0);
+
+ return 0;
+
+err:
+ if ((flags & MEDIA_LNK_FL_ENABLED) && mdev->link_notify)
+ mdev->link_notify(link->source, link->sink, 0);
+
+ return ret;
+}
+
+int media_entity_setup_link(struct media_link *link, u32 flags)
+{
+ int ret;
+
+ mutex_lock(&link->source->entity->parent->graph_mutex);
+ ret = __media_entity_setup_link(link, flags);
+ mutex_unlock(&link->source->entity->parent->graph_mutex);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(media_entity_setup_link);
+
+/**
+ * media_entity_find_link - Find a link between two pads
+ * @source: Source pad
+ * @sink: Sink pad
+ *
+ * Return a pointer to the link between the two entities. If no such link
+ * exists, return NULL.
+ */
+struct media_link *
+media_entity_find_link(struct media_pad *source, struct media_pad *sink)
+{
+ struct media_link *link;
+ unsigned int i;
+
+ for (i = 0; i < source->entity->num_links; ++i) {
+ link = &source->entity->links[i];
+
+ 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);
+
+/**
+ * media_entity_remote_source - Find the source pad at the remote end of a link
+ * @pad: Sink pad at the local end of the link
+ *
+ * Search for a remote source pad connected to the given sink pad by iterating
+ * over all links originating or terminating at that pad until an enabled link
+ * is found.
+ *
+ * Return a pointer to the pad at the remote end of the first found enabled
+ * link, or NULL if no enabled link has been found.
+ */
+struct media_pad *media_entity_remote_source(struct media_pad *pad)
+{
+ unsigned int i;
+
+ for (i = 0; i < pad->entity->num_links; i++) {
+ struct media_link *link = &pad->entity->links[i];
+
+ 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_source);