[PATCH] media: rcar-vin: Clean up notifier on probe failure

[Myeonghun Pak <mhun512@gmail.com>]

rvin_group_notifier_init() initializes the group notifier before
parsing the graph and adding async connections. If parsing fails
after that point, the function returns without cleaning up the
notifier, leaving the async connections and their fwnode references
behind.

The Gen2/default probe path also fails to drop the group reference
when rvin_group_notifier_init() returns an error after
rvin_group_get() succeeded. Unlike a successful probe, .remove() is
not called for this path, so the probe error path must unwind it
directly.

Route notifier-init failures through a common cleanup path, clear
the cached async connection pointers after cleanup, and make the
default probe path mirror the CSI-2/ISP group unwind.

Fixes: 856b49c71ae5 ("media: rcar-vin: Merge all notifiers")
Co-developed-by: Ijae Kim <ae878000@gmail.com>
Signed-off-by: Ijae Kim <ae878000@gmail.com>
Signed-off-by: Myeonghun Pak <mhun512@gmail.com>
---
 .../media/platform/renesas/rcar-vin/rcar-core.c    | 32 ++++++++++++++++++----
 1 file changed, 26 insertions(+), 6 deletions(-)

diff --git a/drivers/media/platform/renesas/rcar-vin/rcar-core.c b/drivers/media/platform/renesas/rcar-vin/rcar-core.c
index c8d564aa1e..8ba8d49c3e 100644
--- a/drivers/media/platform/renesas/rcar-vin/rcar-core.c
+++ b/drivers/media/platform/renesas/rcar-vin/rcar-core.c
@@ -318,6 +318,20 @@ static const struct v4l2_async_notifier_operations rvin_group_notify_ops = {
 	.complete = rvin_group_notify_complete,
 };
 
+static void rvin_group_notifier_cleanup(struct rvin_group *group)
+{
+	v4l2_async_nf_cleanup(&group->notifier);
+
+	guard(mutex)(&group->lock);
+
+	for (unsigned int i = 0; i < RCAR_VIN_NUM; i++)
+		if (group->vin[i])
+			group->vin[i]->parallel.asc = NULL;
+
+	for (unsigned int i = 0; i < ARRAY_SIZE(group->remotes); i++)
+		group->remotes[i].asc = NULL;
+}
+
 static int rvin_group_parse_of(struct rvin_dev *vin, unsigned int port,
 			       unsigned int id)
 {
@@ -440,7 +454,7 @@ static int rvin_group_notifier_init(struct rvin_dev *vin, unsigned int port,
 		/* Parse local subdevice. */
 		ret = rvin_parallel_parse_of(vin->group->vin[i]);
 		if (ret)
-			return ret;
+			goto err_cleanup;
 
 		/* Parse shared subdevices. */
 		for (id = 0; id < max_id; id++) {
@@ -449,7 +463,7 @@ static int rvin_group_notifier_init(struct rvin_dev *vin, unsigned int port,
 
 			ret = rvin_group_parse_of(vin->group->vin[i], port, id);
 			if (ret)
-				return ret;
+				goto err_cleanup;
 		}
 	}
 
@@ -460,11 +474,14 @@ static int rvin_group_notifier_init(struct rvin_dev *vin, unsigned int port,
 	ret = v4l2_async_nf_register(&vin->group->notifier);
 	if (ret < 0) {
 		vin_err(vin, "Notifier registration failed\n");
-		v4l2_async_nf_cleanup(&vin->group->notifier);
-		return ret;
+		goto err_cleanup;
 	}
 
 	return 0;
+
+err_cleanup:
+	rvin_group_notifier_cleanup(vin->group);
+	return ret;
 }
 
 /* -----------------------------------------------------------------------------
@@ -1228,8 +1245,11 @@ static int rcar_vin_probe(struct platform_device *pdev)
 		break;
 	default:
 		ret = rvin_group_get(vin, rvin_parallel_setup_links, NULL);
-		if (!ret)
+		if (!ret) {
 			ret = rvin_group_notifier_init(vin, 0, 0);
+			if (ret)
+				rvin_group_put(vin);
+		}
 
 		if (vin->info->scaler)
 			vin->scaler = vin->info->scaler;
@@ -1264,7 +1284,7 @@ static void rcar_vin_remove(struct platform_device *pdev)
 
 	if (&vin->v4l2_dev == vin->group->notifier.v4l2_dev) {
 		v4l2_async_nf_unregister(&vin->group->notifier);
-		v4l2_async_nf_cleanup(&vin->group->notifier);
+		rvin_group_notifier_cleanup(vin->group);
 	}
 
 	rvin_group_put(vin);
-- 
2.49.0