[PATCH RFC 17/21] SQUASH: media: cadence: csi2rx: Filter streams in get_frame_desc

[Jai Luthra]

With routing and stream-aware APIs support in place, make sure to
propagate frame descriptor information for only the subset of streams
that are routed to the particular source pad.

Signed-off-by: Jai Luthra <j-luthra@xxxxxx>
---
 drivers/media/platform/cadence/cdns-csi2rx.c | 50 +++++++++++++++++++++++++++-
 1 file changed, 49 insertions(+), 1 deletion(-)

diff --git a/drivers/media/platform/cadence/cdns-csi2rx.c b/drivers/media/platform/cadence/cdns-csi2rx.c
index f96638b9f252..a0ccdf72a3b2 100644
--- a/drivers/media/platform/cadence/cdns-csi2rx.c
+++ b/drivers/media/platform/cadence/cdns-csi2rx.c
@@ -670,8 +670,56 @@ static int csi2rx_get_frame_desc(struct v4l2_subdev *subdev, unsigned int pad,
 				 struct v4l2_mbus_frame_desc *fd)
 {
 	struct csi2rx_priv *csi2rx = v4l2_subdev_to_csi2rx(subdev);
+	struct v4l2_mbus_frame_desc source_fd = {0};
+	struct v4l2_subdev_route *route;
+	struct v4l2_subdev_state *state;
+	int ret;
+
+	ret = csi2rx_get_frame_desc_from_source(csi2rx, &source_fd);
+	if (ret)
+		return ret;
+
+	fd->type = V4L2_MBUS_FRAME_DESC_TYPE_CSI2;
+
+	state = v4l2_subdev_lock_and_get_active_state(subdev);
+
+	for_each_active_route(&state->routing, route) {
+		struct v4l2_mbus_frame_desc_entry *source_entry = NULL;
+		unsigned int i;
+
+		if (route->source_pad != pad)
+			continue;
+
+		for (i = 0; i < source_fd.num_entries; i++) {
+			if (source_fd.entry[i].stream == route->sink_stream) {
+				source_entry = &source_fd.entry[i];
+				break;
+			}
+		}
+
+		if (!source_entry) {
+			dev_err(csi2rx->dev,
+				"Failed to find stream from source frame desc\n");
+			ret = -EPIPE;
+			goto err_missing_stream;
+		}
 
-	return csi2rx_get_frame_desc_from_source(csi2rx, fd);
+		fd->entry[fd->num_entries].stream = route->source_stream;
+		fd->entry[fd->num_entries].flags = source_entry->flags;
+		fd->entry[fd->num_entries].length = source_entry->length;
+		fd->entry[fd->num_entries].pixelcode = source_entry->pixelcode;
+		fd->entry[fd->num_entries].bus.csi2.vc =
+			source_entry->bus.csi2.vc;
+		fd->entry[fd->num_entries].bus.csi2.dt =
+			source_entry->bus.csi2.dt;
+
+		fd->num_entries++;
+	}
+
+err_missing_stream:
+	v4l2_subdev_unlock_state(state);
+
+	return ret;
 }
 
 static const struct v4l2_subdev_pad_ops csi2rx_pad_ops = {

-- 
2.43.0