[PATCH v10 2/8] media: subdev: Split V4L2_SUBDEV_ROUTING_NO_STREAM_MIX

[Tomi Valkeinen]

V4L2_SUBDEV_ROUTING_NO_STREAM_MIX routing validation flag means that all
routes from a sink pad must go to the same source pad and all routes
going to the same source pad must originate from the same sink pad.

This does not cover all use cases. For example, if a device routes
all streams from a single sink pad to any of the source pads, but
streams from multiple sink pads can go to the same source pad, the
current flag is too restrictive.

Split the flag into two parts, V4L2_SUBDEV_ROUTING_NO_SINK_STREAM_MIX
and V4L2_SUBDEV_ROUTING_NO_SOURCE_STREAM_MIX, which add the restriction
only on one side of the device. Together they mean the same as
V4L2_SUBDEV_ROUTING_NO_STREAM_MIX.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@xxxxxxxxxxxxxxxx>
---
 drivers/media/v4l2-core/v4l2-subdev.c | 17 +++++++++++++----
 include/media/v4l2-subdev.h           | 16 +++++++++++++---
 2 files changed, 26 insertions(+), 7 deletions(-)

diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c
index 1bebcda2bd20..84ae656c770d 100644
--- a/drivers/media/v4l2-core/v4l2-subdev.c
+++ b/drivers/media/v4l2-core/v4l2-subdev.c
@@ -1678,10 +1678,11 @@ int v4l2_subdev_routing_validate(struct v4l2_subdev *sd,
 		}
 
 		/*
-		 * V4L2_SUBDEV_ROUTING_NO_STREAM_MIX: Streams on the same pad
-		 * may not be routed to streams on different pads.
+		 * V4L2_SUBDEV_ROUTING_NO_SINK_STREAM_MIX: Streams on the same
+		 * sink pad may not be routed to streams on different source
+		 * pads.
 		 */
-		if (disallow & V4L2_SUBDEV_ROUTING_NO_STREAM_MIX) {
+		if (disallow & V4L2_SUBDEV_ROUTING_NO_SINK_STREAM_MIX) {
 			if (remote_pads[route->sink_pad] != U32_MAX &&
 			    remote_pads[route->sink_pad] != route->source_pad) {
 				dev_dbg(sd->dev,
@@ -1690,6 +1691,15 @@ int v4l2_subdev_routing_validate(struct v4l2_subdev *sd,
 				goto out;
 			}
 
+			remote_pads[route->sink_pad] = route->source_pad;
+		}
+
+		/*
+		 * V4L2_SUBDEV_ROUTING_NO_SOURCE_STREAM_MIX: Streams on the same
+		 * source pad may not be routed to streams on different sink
+		 * pads.
+		 */
+		if (disallow & V4L2_SUBDEV_ROUTING_NO_SOURCE_STREAM_MIX) {
 			if (remote_pads[route->source_pad] != U32_MAX &&
 			    remote_pads[route->source_pad] != route->sink_pad) {
 				dev_dbg(sd->dev,
@@ -1698,7 +1708,6 @@ int v4l2_subdev_routing_validate(struct v4l2_subdev *sd,
 				goto out;
 			}
 
-			remote_pads[route->sink_pad] = route->source_pad;
 			remote_pads[route->source_pad] = route->sink_pad;
 		}
 
diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
index 17773be4a4ee..a4331e0a5aeb 100644
--- a/include/media/v4l2-subdev.h
+++ b/include/media/v4l2-subdev.h
@@ -1643,19 +1643,29 @@ u64 v4l2_subdev_state_xlate_streams(const struct v4l2_subdev_state *state,
  * @V4L2_SUBDEV_ROUTING_NO_N_TO_1:
  *	multiple input streams may not be routed to the same output stream
  *	(stream merging)
- * @V4L2_SUBDEV_ROUTING_NO_STREAM_MIX:
- *	streams on the same pad may not be routed to streams on different pads
+ * @V4L2_SUBDEV_ROUTING_NO_SINK_STREAM_MIX:
+ *	streams on the same sink pad may not be routed to streams on different
+ *	source pads
+ * @V4L2_SUBDEV_ROUTING_NO_SOURCE_STREAM_MIX:
+ *	streams on the same source pad may not be routed to streams on different
+ *	sink pads
  * @V4L2_SUBDEV_ROUTING_ONLY_1_TO_1:
  *	only non-overlapping 1-to-1 stream routing is allowed (a combination of
  *	@V4L2_SUBDEV_ROUTING_NO_1_TO_N and @V4L2_SUBDEV_ROUTING_NO_N_TO_1)
+ * @V4L2_SUBDEV_ROUTING_NO_STREAM_MIX:
+ *	streams on the same pad may not be routed to streams on different pads
  */
 enum v4l2_subdev_routing_restriction {
 	V4L2_SUBDEV_ROUTING_NO_1_TO_N = BIT(0),
 	V4L2_SUBDEV_ROUTING_NO_N_TO_1 = BIT(1),
-	V4L2_SUBDEV_ROUTING_NO_STREAM_MIX = BIT(2),
+	V4L2_SUBDEV_ROUTING_NO_SINK_STREAM_MIX = BIT(2),
+	V4L2_SUBDEV_ROUTING_NO_SOURCE_STREAM_MIX = BIT(3),
 	V4L2_SUBDEV_ROUTING_ONLY_1_TO_1 =
 		V4L2_SUBDEV_ROUTING_NO_1_TO_N |
 		V4L2_SUBDEV_ROUTING_NO_N_TO_1,
+	V4L2_SUBDEV_ROUTING_NO_STREAM_MIX =
+		V4L2_SUBDEV_ROUTING_NO_SINK_STREAM_MIX |
+		V4L2_SUBDEV_ROUTING_NO_SOURCE_STREAM_MIX,
 };
 
 /**
-- 
2.34.1