[PATCH 06/10] media: rcar-csi2: Add support for multiplexed streams

[Jacopo Mondi <jacopo+renesas@jmondi.org>]

Create and initialize the v4l2_subdev_state for the R-Car CSI-2 receiver
in order to prepare to support multiplexed transmitters.

Create the subdevice state with v4l2_subdev_init_finalize() and
implement the init_cfg() operation to guarantee the state is initialized
correctly with a set of default routes.

Signed-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
---
 drivers/media/platform/rcar-vin/rcar-csi2.c | 74 ++++++++++++++++++++-
 1 file changed, 72 insertions(+), 2 deletions(-)

diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c b/drivers/media/platform/rcar-vin/rcar-csi2.c
index b8c56d248454..e8a79a30cc49 100644
--- a/drivers/media/platform/rcar-vin/rcar-csi2.c
+++ b/drivers/media/platform/rcar-vin/rcar-csi2.c
@@ -875,11 +875,73 @@ static int rcsi2_get_pad_format(struct v4l2_subdev *sd,
 	return 0;
 }
 
+static int rcsi2_init_cfg(struct v4l2_subdev *sd,
+			  struct v4l2_subdev_state *state)
+{
+	/*
+	 * Routing is fixed for this device: which stream goes to the next
+	 * processing block (VIN) is controlled by link enablement between the
+	 * CSI-2 and the VIN itself.
+	 *
+	 * In example, to route VC 3 to VIN1, as an example: "csi2:3 -> vin1:0"
+	 *
+	 * The routing table is then fixed as streams transmitted on VC x will
+	 * be directed to csi:0/x and will be transmitted to VINs on media link
+	 * csi2:x->vin:0.
+	 */
+	struct v4l2_subdev_route routes[] = {
+		{
+			.sink_pad = RCAR_CSI2_SINK,
+			.sink_stream = 0,
+			.source_pad = RCAR_CSI2_SOURCE_VC0,
+			.source_stream = 0,
+			.flags = V4L2_SUBDEV_ROUTE_FL_ACTIVE,
+		},
+		{
+			.sink_pad = RCAR_CSI2_SINK,
+			.sink_stream = 1,
+			.source_pad = RCAR_CSI2_SOURCE_VC1,
+			.source_stream = 0,
+			.flags = V4L2_SUBDEV_ROUTE_FL_ACTIVE,
+		},
+		{
+			.sink_pad = RCAR_CSI2_SINK,
+			.sink_stream = 2,
+			.source_pad = RCAR_CSI2_SOURCE_VC2,
+			.source_stream = 0,
+			.flags = V4L2_SUBDEV_ROUTE_FL_ACTIVE,
+		},
+		{
+			.sink_pad = RCAR_CSI2_SINK,
+			.sink_stream = 3,
+			.source_pad = RCAR_CSI2_SOURCE_VC3,
+			.source_stream = 0,
+			.flags = V4L2_SUBDEV_ROUTE_FL_ACTIVE,
+		},
+	};
+
+	struct v4l2_subdev_krouting routing = {
+		.num_routes = ARRAY_SIZE(routes),
+		.routes = routes,
+	};
+
+	int ret = v4l2_subdev_routing_validate_1_to_1(&routing);
+	if (ret)
+		return ret;
+
+	v4l2_subdev_lock_state(state);
+	ret = v4l2_subdev_set_routing(sd, state, &routing);
+	v4l2_subdev_unlock_state(state);
+
+	return ret;
+}
+
 static const struct v4l2_subdev_video_ops rcar_csi2_video_ops = {
 	.s_stream = rcsi2_s_stream,
 };
 
 static const struct v4l2_subdev_pad_ops rcar_csi2_pad_ops = {
+	.init_cfg = rcsi2_init_cfg,
 	.set_fmt = rcsi2_set_pad_format,
 	.get_fmt = rcsi2_get_pad_format,
 };
@@ -1494,7 +1556,8 @@ static int rcsi2_probe(struct platform_device *pdev)
 	v4l2_set_subdevdata(&priv->subdev, &pdev->dev);
 	snprintf(priv->subdev.name, V4L2_SUBDEV_NAME_SIZE, "%s %s",
 		 KBUILD_MODNAME, dev_name(&pdev->dev));
-	priv->subdev.flags = V4L2_SUBDEV_FL_HAS_DEVNODE;
+	priv->subdev.flags = V4L2_SUBDEV_FL_HAS_DEVNODE |
+			     V4L2_SUBDEV_FL_MULTIPLEXED;
 
 	priv->subdev.entity.function = MEDIA_ENT_F_PROC_VIDEO_PIXEL_FORMATTER;
 	priv->subdev.entity.ops = &rcar_csi2_entity_ops;
@@ -1515,14 +1578,20 @@ static int rcsi2_probe(struct platform_device *pdev)
 
 	pm_runtime_enable(&pdev->dev);
 
+	ret = v4l2_subdev_init_finalize(&priv->subdev);
+	if (ret)
+		goto error_async;
+
 	ret = v4l2_async_register_subdev(&priv->subdev);
 	if (ret < 0)
-		goto error_async;
+		goto error_subdev;
 
 	dev_info(priv->dev, "%d lanes found\n", priv->lanes);
 
 	return 0;
 
+error_subdev:
+	v4l2_subdev_cleanup(&priv->subdev);
 error_async:
 	v4l2_async_nf_unregister(&priv->notifier);
 	v4l2_async_nf_cleanup(&priv->notifier);
@@ -1539,6 +1608,7 @@ static int rcsi2_remove(struct platform_device *pdev)
 	v4l2_async_nf_unregister(&priv->notifier);
 	v4l2_async_nf_cleanup(&priv->notifier);
 	v4l2_async_unregister_subdev(&priv->subdev);
+	v4l2_subdev_cleanup(&priv->subdev);
 
 	pm_runtime_disable(&pdev->dev);
 
-- 
2.35.0