1 files changed, 69 insertions, 24 deletions

diff --git a/drivers/media/mc/mc-entity.c b/drivers/media/mc/mc-entity.c
index f268cf660..8919df09e 100644
--- a/drivers/media/mc/mc-entity.c
+++ b/drivers/media/mc/mc-entity.c
@@ -509,14 +509,15 @@ static int media_pipeline_walk_push(struct media_pipeline_walk *walk,
 
 /*
  * Move the top entry link cursor to the next link. If all links of the entry
- * have been visited, pop the entry itself.
+ * have been visited, pop the entry itself. Return true if the entry has been
+ * popped.
  */
-static void media_pipeline_walk_pop(struct media_pipeline_walk *walk)
+static bool media_pipeline_walk_pop(struct media_pipeline_walk *walk)
 {
 	struct media_pipeline_walk_entry *entry;
 
 	if (WARN_ON(walk->stack.top < 0))
-		return;
+		return false;
 
 	entry = media_pipeline_walk_top(walk);
 
@@ -526,7 +527,7 @@ static void media_pipeline_walk_pop(struct media_pipeline_walk *walk)
 			walk->stack.top);
 
 		walk->stack.top--;
-		return;
+		return true;
 	}
 
 	entry->links = entry->links->next;
@@ -534,6 +535,8 @@ static void media_pipeline_walk_pop(struct media_pipeline_walk *walk)
 	dev_dbg(walk->mdev->dev,
 		"media pipeline: moved entry %u to next link\n",
 		walk->stack.top);
+
+	return false;
 }
 
 /* Free all memory allocated while walking the pipeline. */
@@ -579,30 +582,24 @@ 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_pad *origin;
 	struct media_link *link;
 	struct media_pad *local;
 	struct media_pad *remote;
+	bool last_link;
 	int ret;
 
-	pad = entry->pad;
+	origin = entry->pad;
 	link = list_entry(entry->links, typeof(*link), list);
-	media_pipeline_walk_pop(walk);
+	last_link = 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) {
+	if (link->source->entity == origin->entity) {
 		local = link->source;
 		remote = link->sink;
 	} else {
@@ -614,25 +611,64 @@ static int media_pipeline_explore_next_link(struct media_pipeline *pipe,
 	 * 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)) {
+	if (origin != local &&
+	    !media_entity_has_pad_interdep(origin->entity, origin->index,
+					   local->index)) {
 		dev_dbg(walk->mdev->dev,
 			"media pipeline: skipping link (no route)\n");
-		return 0;
+		goto done;
 	}
 
 	/*
-	 * Add the local and remote pads of the link to the pipeline and push
-	 * them to the stack, if they're not already present.
+	 * Add the local pad of the link to the pipeline and push it to the
+	 * stack, if not already present.
 	 */
 	ret = media_pipeline_add_pad(pipe, walk, local);
 	if (ret)
 		return ret;
 
+	/* Similarly, add the remote pad, but only if the link is enabled. */
+	if (!(link->flags & MEDIA_LNK_FL_ENABLED)) {
+		dev_dbg(walk->mdev->dev,
+			"media pipeline: skipping link (disabled)\n");
+		goto done;
+	}
+
 	ret = media_pipeline_add_pad(pipe, walk, remote);
 	if (ret)
 		return ret;
 
+done:
+	/*
+	 * If we're done iterating over links, iterate over pads of the entity.
+	 * This is necessary to discover pads that are not connected with any
+	 * link. Those are dead ends from a pipeline exploration point of view,
+	 * but are still part of the pipeline and need to be added to enable
+	 * proper validation.
+	 */
+	if (!last_link)
+		return 0;
+
+	dev_dbg(walk->mdev->dev,
+		"media pipeline: adding unconnected pads of '%s'\n",
+		local->entity->name);
+
+	media_entity_for_each_pad(origin->entity, local) {
+		/*
+		 * Skip the origin pad (already handled), pad that have links
+		 * (already discovered through iterating over links) and pads
+		 * not internally connected.
+		 */
+		if (origin == local || !local->num_links ||
+		    !media_entity_has_pad_interdep(origin->entity, origin->index,
+						   local->index))
+			continue;
+
+		ret = media_pipeline_add_pad(pipe, walk, local);
+		if (ret)
+			return ret;
+	}
+
 	return 0;
 }
 
@@ -744,7 +780,6 @@ __must_check int __media_pipeline_start(struct media_pad *pad,
 		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,
@@ -774,7 +809,6 @@ __must_check int __media_pipeline_start(struct media_pad *pad,
 			/* 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
@@ -812,7 +846,7 @@ __must_check int __media_pipeline_start(struct media_pad *pad,
 		 * 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 &&
+		if ((pad->flags & MEDIA_PAD_FL_MUST_CONNECT) &&
 		    !has_enabled_link) {
 			dev_dbg(mdev->dev,
 				"Pad '%s':%u must be connected by an enabled link\n",
@@ -957,6 +991,9 @@ static void __media_entity_remove_link(struct media_entity *entity,
 
 	/* Remove the reverse links for a data link. */
 	if ((link->flags & MEDIA_LNK_FL_LINK_TYPE) == MEDIA_LNK_FL_DATA_LINK) {
+		link->source->num_links--;
+		link->sink->num_links--;
+
 		if (link->source->entity == entity)
 			remote = link->sink->entity;
 		else
@@ -1017,6 +1054,11 @@ media_create_pad_link(struct media_entity *source, u16 source_pad,
 	struct media_link *link;
 	struct media_link *backlink;
 
+	if (flags & MEDIA_LNK_FL_LINK_TYPE)
+		return -EINVAL;
+
+	flags |= MEDIA_LNK_FL_DATA_LINK;
+
 	if (WARN_ON(!source || !sink) ||
 	    WARN_ON(source_pad >= source->num_pads) ||
 	    WARN_ON(sink_pad >= sink->num_pads))
@@ -1032,7 +1074,7 @@ media_create_pad_link(struct media_entity *source, u16 source_pad,
 
 	link->source = &source->pads[source_pad];
 	link->sink = &sink->pads[sink_pad];
-	link->flags = flags & ~MEDIA_LNK_FL_INTERFACE_LINK;
+	link->flags = flags;
 
 	/* Initialize graph object embedded at the new link */
 	media_gobj_create(source->graph_obj.mdev, MEDIA_GRAPH_LINK,
@@ -1063,6 +1105,9 @@ media_create_pad_link(struct media_entity *source, u16 source_pad,
 	sink->num_links++;
 	source->num_links++;
 
+	link->source->num_links++;
+	link->sink->num_links++;
+
 	return 0;
 }
 EXPORT_SYMBOL_GPL(media_create_pad_link);