media: mc: entity: Add media_entity_pipeline() to access the media pipeline

Replace direct access to the pipe field in drivers with a new helper
function. This will allow easier refactoring of media pipeline handling
in the MC core behind the scenes without affecting drivers.

Signed-off-by: Laurent Pinchart <[e-mail]>
Signed-off-by: Tomi Valkeinen <[e-mail]>
Signed-off-by: Sakari Ailus <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

drivers/media/mc/mc-entity.c

···
 }
 EXPORT_SYMBOL_GPL(media_entity_get_fwnode_pad);
 
+struct media_pipeline *media_entity_pipeline(struct media_entity *entity)
+{
+	return entity->pipe;
+}
+EXPORT_SYMBOL_GPL(media_entity_pipeline);
+
 static void media_interface_init(struct media_device *mdev,
 				 struct media_interface *intf,
 				 u32 gobj_type,

drivers/media/platform/renesas/rcar-vin/rcar-core.c

···
 		return 0;
 
 	/*
-	 * Don't allow link changes if any entity in the graph is
-	 * streaming, modifying the CHSEL register fields can disrupt
-	 * running streams.
+	 * Don't allow link changes if any stream in the graph is active as
+	 * modifying the CHSEL register fields can disrupt running streams.
 	 */
 	media_device_for_each_entity(entity, &group->mdev)
 		if (media_entity_is_streaming(entity))

drivers/media/platform/renesas/rcar-vin/rcar-dma.c

···
 	 */
 	mdev = vin->vdev.entity.graph_obj.mdev;
 	mutex_lock(&mdev->graph_mutex);
-	pipe = sd->entity.pipe ? sd->entity.pipe : &vin->vdev.pipe;
+	pipe = media_entity_pipeline(&sd->entity) ? : &vin->vdev.pipe;
 	ret = __media_pipeline_start(&vin->vdev.entity, pipe);
 	mutex_unlock(&mdev->graph_mutex);
 	if (ret)

drivers/media/platform/ti/omap3isp/isp.c

···
 	struct isp_pipeline *pipe;
 	struct media_pad *pad;
 
-	if (!me->pipe)
-		return 0;
 	pipe = to_isp_pipeline(me);
-	if (pipe->stream_state == ISP_PIPELINE_STREAM_STOPPED)
+	if (!pipe || pipe->stream_state == ISP_PIPELINE_STREAM_STOPPED)
 		return 0;
 	pad = media_pad_remote_pad_first(&pipe->output->pad);
 	return pad->entity == me;

drivers/media/platform/ti/omap3isp/ispvideo.c

···
 	/* Start streaming on the pipeline. No link touching an entity in the
 	 * pipeline can be activated or deactivated once streaming is started.
 	 */
-	pipe = video->video.entity.pipe
-	     ? to_isp_pipeline(&video->video.entity) : &video->pipe;
+	pipe = to_isp_pipeline(&video->video.entity) ? : &video->pipe;
 
 	ret = media_entity_enum_init(&pipe->ent_enum, &video->isp->media_dev);
 	if (ret)

drivers/media/platform/ti/omap3isp/ispvideo.h

···
 	unsigned int external_width;
 };
 
-#define to_isp_pipeline(__e) \
-	container_of((__e)->pipe, struct isp_pipeline, pipe)
+static inline struct isp_pipeline *to_isp_pipeline(struct media_entity *entity)
+{
+	struct media_pipeline *pipe = media_entity_pipeline(entity);
+
+	if (!pipe)
+		return NULL;
+
+	return container_of(pipe, struct isp_pipeline, pipe);
+}
 
 static inline int isp_pipeline_ready(struct isp_pipeline *pipe)
 {

drivers/media/platform/xilinx/xilinx-dma.c

···
 	 * Use the pipeline object embedded in the first DMA object that starts
 	 * streaming.
 	 */
-	pipe = dma->video.entity.pipe
-	     ? to_xvip_pipeline(&dma->video.entity) : &dma->pipe;
+	pipe = to_xvip_pipeline(&dma->video.entity) ? : &dma->pipe;
 
 	ret = media_pipeline_start(&dma->video.entity, &pipe->pipe);
 	if (ret < 0)

drivers/media/platform/xilinx/xilinx-dma.h

···
 
 static inline struct xvip_pipeline *to_xvip_pipeline(struct media_entity *e)
 {
-	return container_of(e->pipe, struct xvip_pipeline, pipe);
+	struct media_pipeline *pipe = media_entity_pipeline(e);
+
+	if (!pipe)
+		return NULL;
+
+	return container_of(pipe, struct xvip_pipeline, pipe);
 }
 
 /**

drivers/staging/media/imx/imx-media-utils.c

···
 			__media_pipeline_stop(entity);
 	} else {
 		v4l2_subdev_call(sd, video, s_stream, 0);
-		if (entity->pipe)
+		if (media_entity_pipeline(entity))
 			__media_pipeline_stop(entity);
 	}
 

drivers/staging/media/omap4iss/iss.c

···
 	struct iss_pipeline *pipe;
 	struct media_pad *pad;
 
-	if (!me->pipe)
-		return 0;
 	pipe = to_iss_pipeline(me);
-	if (pipe->stream_state == ISS_PIPELINE_STREAM_STOPPED)
+	if (!pipe || pipe->stream_state == ISS_PIPELINE_STREAM_STOPPED)
 		return 0;
 	pad = media_pad_remote_pad_first(&pipe->output->pad);
 	return pad->entity == me;

drivers/staging/media/omap4iss/iss_video.c

···
 	 * Start streaming on the pipeline. No link touching an entity in the
 	 * pipeline can be activated or deactivated once streaming is started.
 	 */
-	pipe = entity->pipe
-	     ? to_iss_pipeline(entity) : &video->pipe;
+	pipe = to_iss_pipeline(&video->video.entity) ? : &video->pipe;
 	pipe->external = NULL;
 	pipe->external_rate = 0;
 	pipe->external_bpp = 0;

drivers/staging/media/omap4iss/iss_video.h

···
 	int external_bpp;
 };
 
-#define to_iss_pipeline(__e) \
-	container_of((__e)->pipe, struct iss_pipeline, pipe)
+static inline struct iss_pipeline *to_iss_pipeline(struct media_entity *entity)
+{
+	struct media_pipeline *pipe = media_entity_pipeline(entity);
+
+	if (!pipe)
+		return NULL;
+
+	return container_of(pipe, struct iss_pipeline, pipe);
+}
 
 static inline int iss_pipeline_ready(struct iss_pipeline *pipe)
 {

include/media/media-entity.h

···
 }
 
 /**
+ * media_entity_pipeline - Get the media pipeline an entity is part of
+ * @entity: The entity
+ *
+ * This function returns the media pipeline that an entity has been associated
+ * with when constructing the pipeline with media_pipeline_start(). The pointer
+ * remains valid until media_pipeline_stop() is called.
+ *
+ * In general, entities can be part of multiple pipelines, when carrying
+ * multiple streams (either on different pads, or on the same pad using
+ * multiplexed streams). This function is to be used only for entities that
+ * do not support multiple pipelines.
+ *
+ * Return: The media_pipeline the entity is part of, or NULL if the entity is
+ * not part of any pipeline.
+ */
+struct media_pipeline *media_entity_pipeline(struct media_entity *entity);
+
+/**
  * media_entity_get_fwnode_pad - Get pad number from fwnode
  *
  * @entity: The entity