[media] media: Change media device link_notify behaviour

Currently the media device link_notify callback is invoked before the
actual change of state of a link when the link is being enabled, and
after the actual change of state when the link is being disabled.
This doesn't allow a media device driver to perform any operations
on a full graph before a link is disabled, as well as performing
any tasks on a modified graph right after a link's state is changed.
This patch modifies signature of the link_notify callback. This
callback is now called always before and after a link's state change.
To distinguish the notifications a 'notification' argument is added
to the link_notify callback: MEDIA_DEV_NOTIFY_PRE_LINK_CH indicates
notification before link's state change and
MEDIA_DEV_NOTIFY_POST_LINK_CH corresponds to a notification after
link flags change.

[mchehab@redhat.com: whitespace cleanups]
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Sakari Ailus <sakari.ailus@iki.fi>

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 10 insertions, 8 deletions

diff --git a/drivers/media/platform/exynos4-is/media-dev.c b/drivers/media/platform/exynos4-is/media-dev.c
index b5624931d16..5298dd6680a 100644
--- a/drivers/media/platform/exynos4-is/media-dev.c
+++ b/drivers/media/platform/exynos4-is/media-dev.c
@@ -1287,34 +1287,36 @@ int fimc_md_set_camclk(struct v4l2_subdev *sd, bool on)
 	return __fimc_md_set_camclk(fmd, si, on);
 }
 
-static int fimc_md_link_notify(struct media_pad *source,
-			       struct media_pad *sink, u32 flags)
+static int fimc_md_link_notify(struct media_link *link, u32 flags,
+						unsigned int notification)
 {
+	struct media_entity *sink = link->sink->entity;
 	struct exynos_video_entity *ve;
 	struct video_device *vdev;
 	struct fimc_pipeline *pipeline;
 	int i, ret = 0;
 
-	if (media_entity_type(sink->entity) != MEDIA_ENT_T_DEVNODE_V4L)
+	if (media_entity_type(sink) != MEDIA_ENT_T_DEVNODE_V4L ||
+	    notification == MEDIA_DEV_NOTIFY_PRE_LINK_CH)
 		return 0;
 
-	vdev = media_entity_to_video_device(sink->entity);
+	vdev = media_entity_to_video_device(sink);
 	ve = vdev_to_exynos_video_entity(vdev);
 	pipeline = to_fimc_pipeline(ve->pipe);
 
-	if (!(flags & MEDIA_LNK_FL_ENABLED) && pipeline->subdevs[IDX_SENSOR]) {
-		if (sink->entity->use_count > 0)
+	if (!(link->flags & MEDIA_LNK_FL_ENABLED) && pipeline->subdevs[IDX_SENSOR]) {
+		if (sink->use_count > 0)
 			ret = __fimc_pipeline_close(ve->pipe);
 
 		for (i = 0; i < IDX_MAX; i++)
 			pipeline->subdevs[i] = NULL;
-	} else if (sink->entity->use_count > 0) {
+	} else if (sink->use_count > 0) {
 		/*
 		 * Link activation. Enable power of pipeline elements only if
 		 * the pipeline is already in use, i.e. its video node is open.
 		 * Recreate the controls destroyed during the link deactivation.
 		 */
-		ret = __fimc_pipeline_open(ve->pipe, sink->entity, true);
+		ret = __fimc_pipeline_open(ve->pipe, sink, true);
 	}
 
 	return ret ? -EPIPE : ret;