[PATCH/RFC v2 27/56] media: Gather link configuration into media request

[Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>]

From: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>

Add a list of struct media_link_request to media requests to gather link
setup operations.

Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
---
 drivers/media/media-device.c | 60 +++++++++++++++++++++++++++++++++++++++-----
 include/media/media-device.h |  3 +++
 include/media/media-entity.h | 12 +++++++++
 3 files changed, 69 insertions(+), 6 deletions(-)

diff --git a/drivers/media/media-device.c b/drivers/media/media-device.c
index 3850775cc127..686d4bc55a51 100644
--- a/drivers/media/media-device.c
+++ b/drivers/media/media-device.c
@@ -86,15 +86,20 @@ EXPORT_SYMBOL_GPL(media_device_request_get);
 
 static void media_device_request_release(struct kref *kref)
 {
-	struct media_entity_request_data *data, *next;
+	struct media_entity_request_data *data, *data_safe;
 	struct media_device_request *req =
 		container_of(kref, struct media_device_request, kref);
 	struct media_device *mdev = req->mdev;
+	struct media_request_link *rlnk, *rlnk_safe;
 
-	list_for_each_entry_safe(data, next, &req->data, list) {
+	list_for_each_entry_safe(data, data_safe, &req->data, list) {
 		list_del(&data->list);
 		data->release(data);
 	}
+	list_for_each_entry_safe(rlnk, rlnk_safe, &req->links, list) {
+		list_del(&rlnk->list);
+		kfree(rlnk);
+	}
 
 	mdev->ops->req_free(mdev, req);
 }
@@ -105,6 +110,19 @@ void media_device_request_put(struct media_device_request *req)
 }
 EXPORT_SYMBOL_GPL(media_device_request_put);
 
+struct media_request_link *media_device_request_link_find(
+	struct media_device_request *req, struct media_link *link)
+{
+	struct media_request_link *rlnk;
+
+	list_for_each_entry(rlnk, &req->links, list) {
+		if (rlnk->link == link)
+			return rlnk;
+	}
+
+	return NULL;
+}
+
 /**
  * media_device_request_get_entity_data - Get per-entity data
  * @req: The request
@@ -182,6 +200,7 @@ static int media_device_request_alloc(struct media_device *mdev,
 
 	req->mdev = mdev;
 	kref_init(&req->kref);
+	INIT_LIST_HEAD(&req->links);
 	INIT_LIST_HEAD(&req->data);
 
 	spin_lock_irqsave(&mdev->req_lock, flags);
@@ -463,6 +482,7 @@ static long media_device_setup_link(struct media_device *mdev,
 {
 	struct media_link *link = NULL;
 	struct media_link_desc ulink;
+	struct media_device_request *req = NULL;
 	struct media_entity *source;
 	struct media_entity *sink;
 	int ret = -EINVAL;
@@ -470,7 +490,13 @@ static long media_device_setup_link(struct media_device *mdev,
 	if (copy_from_user(&ulink, _ulink, sizeof(ulink)))
 		return -EFAULT;
 
-	mutex_lock(&dev->graph_mutex);
+	if (ulink.request) {
+		req = media_device_request_find(mdev, ulink.request);
+		if (!req)
+			return -ENOENT;
+	}
+
+	mutex_lock(&mdev->graph_mutex);
 
 	/* Find the source and sink entities and link.
 	 */
@@ -489,11 +515,33 @@ static long media_device_setup_link(struct media_device *mdev,
 	if (link == NULL)
 		goto out;
 
-	/* Setup the link on both entities. */
-	ret = __media_entity_setup_link(link, ulink.flags);
+	if (req) {
+		struct media_request_link *rlnk =
+			media_device_request_link_find(req, link);
+
+		if (rlnk) {
+			list_del(&rlnk->list);
+		} else {
+			rlnk = kmalloc(sizeof(*rlnk), GFP_KERNEL);
+			if (!rlnk) {
+				ret = -ENOMEM;
+				goto out;
+			}
+		}
+
+		rlnk->link = link;
+		rlnk->enabled = ulink.flags & MEDIA_LNK_FL_ENABLED;
+		list_add(&rlnk->list, &req->links);
+	} else {
+		/* Setup the link on both entities. */
+		ret = __media_entity_setup_link(link, ulink.flags);
+	}
 
 out:
-	mutex_unlock(&dev->graph_mutex);
+	mutex_unlock(&mdev->graph_mutex);
+
+	if (req)
+		media_device_request_put(req);
 
 	if (!ret && copy_to_user(_ulink, &ulink, sizeof(ulink)))
 		ret = -EFAULT;
diff --git a/include/media/media-device.h b/include/media/media-device.h
index 0a374328a135..3278c5db5a26 100644
--- a/include/media/media-device.h
+++ b/include/media/media-device.h
@@ -41,6 +41,8 @@ struct media_device;
  * @kref: Reference count
  * @list: List entry in the media device requests list
  * @fh_list: List entry in the media file handle requests list
+ * @links: List of links state changes included in the request
+ *	   (struct media_request_link)
  * @data: Per-entity data list
  */
 struct media_device_request {
@@ -49,6 +51,7 @@ struct media_device_request {
 	struct kref kref;
 	struct list_head list;
 	struct list_head fh_list;
+	struct list_head links;
 	struct list_head data;
 };
 
diff --git a/include/media/media-entity.h b/include/media/media-entity.h
index 36e2129e61c6..ee5bace06730 100644
--- a/include/media/media-entity.h
+++ b/include/media/media-entity.h
@@ -134,6 +134,18 @@ struct media_entity_graph {
 };
 
 /**
+ * struct media_request_link - Request link state changes
+ * @list: List head for the list in struct media_device_request.links
+ * @link: The link the state of which is to be changed
+ * @enabled: Whether the link is to be enabled or not
+ */
+struct media_request_link {
+	struct list_head list;
+	struct media_link *link;
+	bool enabled;
+};
+
+/**
  * struct media_entity_request_data - Per-entity request data
  * @entity: Entity this data belongs to
  * @release: Release operation to free the data
-- 
2.4.10