From 97548ed4c4661502cdfd1aabd5d3876fa4f5cc2e Mon Sep 17 00:00:00 2001 From: Laurent Pinchart Date: Wed, 9 Dec 2009 08:40:03 -0300 Subject: [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 Signed-off-by: Stanimir Varbanov Signed-off-by: Sakari Ailus Acked-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- drivers/media/media-entity.c | 155 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 155 insertions(+) (limited to 'drivers/media/media-entity.c') 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); -- cgit v1.2.3