media: subdev: add v4l2_subdev_has_pad_interdep()

Add a v4l2_subdev_has_pad_interdep() helper function which can be used
for media_entity_operations.has_pad_interdep op.

It considers two pads interdependent if there is an active route between
pad0 and pad1.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c
index 6cdb7a8..dd67b4a 100644 (file)
--- a/drivers/media/v4l2-core/v4l2-subdev.c
+++ b/drivers/media/v4l2-core/v4l2-subdev.c
@@ -1073,6 +1073,37 @@ int v4l2_subdev_link_validate(struct media_link *link)
 }
 EXPORT_SYMBOL_GPL(v4l2_subdev_link_validate);
 
+bool v4l2_subdev_has_pad_interdep(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;
+       struct v4l2_subdev_state *state;
+       unsigned int i;
+
+       state = v4l2_subdev_lock_and_get_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_pad_interdep);
+
 struct v4l2_subdev_state *
 __v4l2_subdev_state_alloc(struct v4l2_subdev *sd, const char *lock_name,
                          struct lock_class_key *lock_key)

diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
index 67e5575..0bd674a 100644 (file)
--- a/include/media/v4l2-subdev.h
+++ b/include/media/v4l2-subdev.h
@@ -1247,6 +1247,24 @@ int v4l2_subdev_link_validate_default(struct v4l2_subdev *sd,
 int v4l2_subdev_link_validate(struct media_link *link);
 
 /**
+ * v4l2_subdev_has_pad_interdep - MC has_pad_interdep 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 is an implementation of the
+ * media_entity_operations.has_pad_interdep operation for subdevs that
+ * implement the multiplexed streams API (as indicated by the
+ * V4L2_SUBDEV_FL_STREAMS subdev flag).
+ *
+ * It considers two pads interdependent if there is an active route between pad0
+ * and pad1.
+ */
+bool v4l2_subdev_has_pad_interdep(struct media_entity *entity,
+                                 unsigned int pad0, unsigned int pad1);
+
+/**
  * __v4l2_subdev_state_alloc - allocate v4l2_subdev_state
  *
  * @sd: pointer to &struct v4l2_subdev for which the state is being allocated.