/* * Media entity * * Copyright (C) 2010 Nokia Corporation * * Contacts: Laurent Pinchart * Sakari Ailus * * 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. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include #include #include #include #include /** * 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 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 "frontend"; case MEDIA_INTF_T_DVB_DEMUX: return "demux"; case MEDIA_INTF_T_DVB_DVR: return "DVR"; case MEDIA_INTF_T_DVB_CA: return "CA"; case MEDIA_INTF_T_DVB_NET: return "dvbnet"; case MEDIA_INTF_T_V4L_VIDEO: return "video"; case MEDIA_INTF_T_V4L_VBI: return "vbi"; case MEDIA_INTF_T_V4L_RADIO: return "radio"; case MEDIA_INTF_T_V4L_SUBDEV: return "v4l2-subdev"; case MEDIA_INTF_T_V4L_SWRADIO: return "swradio"; default: return "unknown-intf"; } }; 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 0x%08x entity#%d: '%s'\n", event_name, gobj->id, media_localid(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 0x%08x link#%d: %s#%d ==> %s#%d\n", event_name, gobj->id, media_localid(gobj), gobj_type(media_type(link->gobj0)), media_localid(link->gobj0), gobj_type(media_type(link->gobj1)), media_localid(link->gobj1)); break; } case MEDIA_GRAPH_PAD: { struct media_pad *pad = gobj_to_pad(gobj); dev_dbg(gobj->mdev->dev, "%s: id 0x%08x %s%spad#%d: '%s':%d\n", event_name, gobj->id, pad->flags & MEDIA_PAD_FL_SINK ? " sink " : "", pad->flags & MEDIA_PAD_FL_SOURCE ? "source " : "", media_localid(gobj), 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 0x%08x intf_devnode#%d: %s - major: %d, minor: %d\n", event_name, gobj->id, media_localid(gobj), intf_type(intf), devnode->major, devnode->minor); break; } } #endif } /** * media_gobj_init - Initialize a graph object * * @mdev: Pointer to the media_device that contains the object * @type: Type of the object * @gobj: Pointer to the object * * This routine initializes the embedded struct media_gobj inside a * media graph object. It is called automatically if media_*_create() * calls are used. However, if the object (entity, link, pad, interface) * is embedded on some other object, this function should be called before * registering the object at the media controller. */ void media_gobj_init(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 */ switch (type) { case MEDIA_GRAPH_ENTITY: gobj->id = media_gobj_gen_id(type, ++mdev->entity_id); list_add_tail(&gobj->list, &mdev->entities); break; case MEDIA_GRAPH_PAD: gobj->id = media_gobj_gen_id(type, ++mdev->pad_id); list_add_tail(&gobj->list, &mdev->pads); break; case MEDIA_GRAPH_LINK: gobj->id = media_gobj_gen_id(type, ++mdev->link_id); list_add_tail(&gobj->list, &mdev->links); break; case MEDIA_GRAPH_INTF_DEVNODE: gobj->id = media_gobj_gen_id(type, ++mdev->intf_devnode_id); list_add_tail(&gobj->list, &mdev->interfaces); break; } mdev->topology_version++; dev_dbg_obj(__func__, gobj); } /** * media_gobj_remove - Stop using a graph object on a media device * * @graph_obj: Pointer to the object * * This should be called at media_device_unregister_*() routines */ void media_gobj_remove(struct media_gobj *gobj) { dev_dbg_obj(__func__, gobj); gobj->mdev->topology_version++; /* Remove the object from mdev list */ list_del(&gobj->list); } /** * media_entity_init - Initialize a media entity * * @num_pads: Total number of sink and source pads. * @pads: Array of 'num_pads' pads. * * The total number of pads is an intrinsic property of entities known by the * entity driver, while the total number of links depends on hardware design * and is an extrinsic property unknown to the entity driver. However, in most * use cases the number of links can safely be assumed to be equal to or * larger than the number of pads. * * For those reasons the links array can be preallocated based on the number * of pads and will be reallocated later if extra links need to be created. * * This function allocates a links array with enough space to hold at least * 'num_pads' elements. The media_entity::max_links field will be set to the * number of allocated elements. * * The pads array is managed by the entity driver and passed to * media_entity_init() where its pointer will be stored in the entity structure. */ int media_entity_init(struct media_entity *entity, u16 num_pads, struct media_pad *pads) { unsigned int i; entity->group_id = 0; entity->num_links = 0; entity->num_backlinks = 0; entity->num_pads = num_pads; entity->pads = pads; for (i = 0; i < num_pads; i++) { pads[i].entity = entity; pads[i].index = i; } return 0; } EXPORT_SYMBOL_GPL(media_entity_init); void media_entity_cleanup(struct media_entity *entity) { } EXPORT_SYMBOL_GPL(media_entity_cleanup); /* ----------------------------------------------------------------------------- * 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_entity_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_entity_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_entity_graph_walk_start - Start walking the media graph at a given entity * @graph: Media graph structure that will be used to walk the graph * @entity: Starting entity * * This function initializes the graph traversal structure to walk the entities * graph starting at the given entity. The traversal structure must not be * modified by the caller during graph traversal. When done the structure can * safely be freed. */ void media_entity_graph_walk_start(struct media_entity_graph *graph, struct media_entity *entity) { graph->top = 0; graph->stack[graph->top].entity = NULL; bitmap_zero(graph->entities, MEDIA_ENTITY_ENUM_MAX_ID); if (WARN_ON(media_entity_id(entity) >= MEDIA_ENTITY_ENUM_MAX_ID)) return; __set_bit(media_entity_id(entity), graph->entities); stack_push(graph, entity); } EXPORT_SYMBOL_GPL(media_entity_graph_walk_start); /** * media_entity_graph_walk_next - Get the next entity in the graph * @graph: Media graph structure * * Perform a depth-first traversal of the given media entities graph. * * The graph structure must have been previously initialized with a call to * media_entity_graph_walk_start(). * * Return the next entity in the graph or NULL if the whole graph have been * traversed. */ struct media_entity * media_entity_graph_walk_next(struct media_entity_graph *graph) { 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)) { 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; continue; } /* Get the entity in the other end of the link . */ next = media_entity_other(entity, link); if (WARN_ON(media_entity_id(next) >= MEDIA_ENTITY_ENUM_MAX_ID)) return NULL; /* Has the entity already been visited? */ if (__test_and_set_bit(media_entity_id(next), graph->entities)) { link_top(graph) = link_top(graph)->next; continue; } /* Push the new entity to stack and start over. */ link_top(graph) = link_top(graph)->next; stack_push(graph, next); } return stack_pop(graph); } EXPORT_SYMBOL_GPL(media_entity_graph_walk_next); /* ----------------------------------------------------------------------------- * Pipeline management */ /** * media_entity_pipeline_start - Mark a pipeline as streaming * @entity: Starting entity * @pipe: Media pipeline to be assigned to all entities in the pipeline. * * Mark all entities connected to a given entity through enabled links, either * directly or indirectly, as streaming. The given pipeline object is assigned to * every entity in the pipeline and stored in the media_entity pipe field. * * Calls to this function can be nested, in which case the same number of * media_entity_pipeline_stop() calls will be required to stop streaming. The * pipeline pointer must be identical for all nested calls to * media_entity_pipeline_start(). */ __must_check int media_entity_pipeline_start(struct media_entity *entity, struct media_pipeline *pipe) { struct media_device *mdev = entity->graph_obj.mdev; struct media_entity_graph graph; struct media_entity *entity_err = entity; struct media_link *link; int ret; mutex_lock(&mdev->graph_mutex); media_entity_graph_walk_start(&graph, entity); while ((entity = media_entity_graph_walk_next(&graph))) { DECLARE_BITMAP(active, MEDIA_ENTITY_MAX_PADS); DECLARE_BITMAP(has_no_links, MEDIA_ENTITY_MAX_PADS); entity->stream_count++; WARN_ON(entity->pipe && entity->pipe != pipe); 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 = -EPIPE; 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; } } mutex_unlock(&mdev->graph_mutex); return 0; error: /* * Link validation on graph failed. We revert what we did and * return the error. */ media_entity_graph_walk_start(&graph, entity_err); while ((entity_err = media_entity_graph_walk_next(&graph))) { 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; } mutex_unlock(&mdev->graph_mutex); return ret; } EXPORT_SYMBOL_GPL(media_entity_pipeline_start); /** * media_entity_pipeline_stop - Mark a pipeline as not streaming * @entity: Starting entity * * Mark all entities connected to a given entity through enabled links, either * directly or indirectly, as not streaming. The media_entity pipe field is * reset to NULL. * * If multiple calls to media_entity_pipeline_start() have been made, the same * number of calls to this function are required to mark the pipeline as not * streaming. */ void media_entity_pipeline_stop(struct media_entity *entity) { struct media_device *mdev = entity->graph_obj.mdev; struct media_entity_graph graph; mutex_lock(&mdev->graph_mutex); media_entity_graph_walk_start(&graph, entity); while ((entity = media_entity_graph_walk_next(&graph))) { entity->stream_count--; if (entity->stream_count == 0) entity->pipe = NULL; } mutex_unlock(&mdev->graph_mutex); } EXPORT_SYMBOL_GPL(media_entity_pipeline_stop); /* ----------------------------------------------------------------------------- * Module use count */ /* * media_entity_get - Get a reference to the parent module * @entity: The entity * * Get a reference to the parent media device module. * * The function will return immediately if @entity is NULL. * * Return a pointer to the entity on success or NULL on failure. */ struct media_entity *media_entity_get(struct media_entity *entity) { if (entity == NULL) return NULL; if (entity->graph_obj.mdev->dev && !try_module_get(entity->graph_obj.mdev->dev->driver->owner)) return NULL; return entity; } EXPORT_SYMBOL_GPL(media_entity_get); /* * media_entity_put - Release the reference to the parent module * @entity: The entity * * Release the reference count acquired by media_entity_get(). * * The function will return immediately if @entity is NULL. */ void media_entity_put(struct media_entity *entity) { if (entity == NULL) return; if (entity->graph_obj.mdev->dev) module_put(entity->graph_obj.mdev->dev->driver->owner); } EXPORT_SYMBOL_GPL(media_entity_put); /* ----------------------------------------------------------------------------- * 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); 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; /* Initialize graph object embedded at the new link */ media_gobj_init(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; /* Initialize graph object embedded at the new link */ media_gobj_init(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); static void __media_entity_remove_link(struct media_entity *entity, struct media_link *link) { struct media_link *rlink, *tmp; struct media_entity *remote; unsigned int r = 0; 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) { r++; continue; } if (link->source->entity == entity) remote->num_backlinks--; /* Remove the remote link */ list_del(&rlink->list); media_gobj_remove(&rlink->graph_obj); kfree(rlink); if (--remote->num_links == 0) break; } list_del(&link->list); media_gobj_remove(&link->graph_obj); kfree(link); } 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) { /* Do nothing if the entity is not registered. */ if (entity->graph_obj.mdev == NULL) return; spin_lock(&entity->graph_obj.mdev->lock); __media_entity_remove_links(entity); spin_unlock(&entity->graph_obj.mdev->lock); } 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; } /** * __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) { 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->link_notify) { ret = mdev->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->link_notify) mdev->link_notify(link, flags, MEDIA_DEV_NOTIFY_POST_LINK_CH); return ret; } int media_entity_setup_link(struct media_link *link, u32 flags) { int ret; spin_lock(&link->source->entity->graph_obj.mdev->lock); ret = __media_entity_setup_link(link, flags); spin_unlock(&link->source->entity->graph_obj.mdev->lock); 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; 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); /** * media_entity_remote_pad - Find the pad at the remote end of a link * @pad: Pad at the local end of the link * * Search for a remote pad connected to the given 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_pad(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_init(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, gfp_t gfp_flags) { struct media_intf_devnode *devnode; devnode = kzalloc(sizeof(*devnode), gfp_flags); 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_remove(&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; /* Initialize graph object embedded at the new link */ media_gobj_init(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_remove(&link->graph_obj); kfree(link); } EXPORT_SYMBOL_GPL(__media_remove_intf_link); void media_remove_intf_link(struct media_link *link) { spin_lock(&link->graph_obj.mdev->lock); __media_remove_intf_link(link); spin_unlock(&link->graph_obj.mdev->lock); } 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) { /* Do nothing if the intf is not registered. */ if (intf->graph_obj.mdev == NULL) return; spin_lock(&intf->graph_obj.mdev->lock); __media_remove_intf_links(intf); spin_unlock(&intf->graph_obj.mdev->lock); } EXPORT_SYMBOL_GPL(media_remove_intf_links);