[PATCH v8 29/36] media: subdev: add v4l2_subdev_has_route()

[Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>]

Add a v4l2_subdev_has_route() helper function which can be used for
media_entity_operations.has_route op.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
---
 drivers/media/v4l2-core/v4l2-subdev.c | 30 +++++++++++++++++++++++++++
 include/media/v4l2-subdev.h           | 16 ++++++++++++++
 2 files changed, 46 insertions(+)

diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c
index 0e1f325b3159..7497ad0f6024 100644
--- a/drivers/media/v4l2-core/v4l2-subdev.c
+++ b/drivers/media/v4l2-core/v4l2-subdev.c
@@ -999,6 +999,36 @@ int v4l2_subdev_link_validate(struct media_link *link)
 }
 EXPORT_SYMBOL_GPL(v4l2_subdev_link_validate);
 
+bool v4l2_subdev_has_route(struct media_entity *entity, unsigned int pad0, unsigned int pad1)
+{
+	struct v4l2_subdev *sd = media_entity_to_v4l2_subdev(entity);
+	struct v4l2_subdev_krouting *routing;
+	unsigned int i;
+	struct v4l2_subdev_state *state;
+
+	state = v4l2_subdev_lock_active_state(sd);
+
+	routing = &state->routing;
+
+	for (i = 0; i < routing->num_routes; ++i) {
+		struct v4l2_subdev_route *route = &routing->routes[i];
+
+		if (!(route->flags & V4L2_SUBDEV_ROUTE_FL_ACTIVE))
+			continue;
+
+		if ((route->sink_pad == pad0 && route->source_pad == pad1) ||
+		    (route->source_pad == pad0 && route->sink_pad == pad1)) {
+			v4l2_subdev_unlock_state(state);
+			return true;
+		}
+	}
+
+	v4l2_subdev_unlock_state(state);
+
+	return false;
+}
+EXPORT_SYMBOL_GPL(v4l2_subdev_has_route);
+
 struct v4l2_subdev_state *
 __v4l2_alloc_subdev_state(struct v4l2_subdev *sd,
 			  enum v4l2_subdev_format_whence which,
diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
index cd6aad21ae0c..858e18aa5b20 100644
--- a/include/media/v4l2-subdev.h
+++ b/include/media/v4l2-subdev.h
@@ -1213,6 +1213,22 @@ int v4l2_subdev_link_validate_default(struct v4l2_subdev *sd,
  */
 int v4l2_subdev_link_validate(struct media_link *link);
 
+/**
+ * v4l2_subdev_has_route - MC has_route implementation for subdevs
+ *
+ * @entity: pointer to &struct media_entity
+ * @pad0: pad number for the first pad
+ * @pad1: pad number for the second pad
+ *
+ * This function looks at the routing in subdev's active state and returns if
+ * there is a route connecting pad0 and pad1.
+ *
+ * This function can be used as implementation for
+ * media_entity_operations.has_route.
+ */
+bool v4l2_subdev_has_route(struct media_entity *entity, unsigned int pad0,
+			   unsigned int pad1);
+
 /**
  * v4l2_alloc_subdev_state - allocate v4l2_subdev_state
  *
-- 
2.25.1