[PATCH v2] media: rp1-cfe: Use IS_ERR() check for media_entity_remote_source_pad_unique()

[Ingyu Jang]

media_entity_remote_source_pad_unique() returns either a valid struct
media_pad pointer or an error pointer (ERR_PTR(-ENOTUNIQ) or
ERR_PTR(-ENOLINK)); it never returns NULL. The current NULL check
therefore never triggers, and the "pad not connected" error path is
unreachable.

Replace the NULL check with an IS_ERR() check so the validation
actually detects malformed media graphs.

Fixes: 6edb685abb2a ("media: raspberrypi: Add support for RP1-CFE")
Cc: stable at vger.kernel.org
Signed-off-by: Ingyu Jang <ingyujang25 at korea.ac.kr>
Reviewed-by: Dave Stevenson <dave.stevenson at raspberrypi.com>
Reviewed-by: Jai Luthra <jai.luthra at ideasonboard.com>
---
Changes in v2:
- Add Fixes: and Cc: stable tags, as requested by Jai Luthra.
- Collect Reviewed-by tags from Dave Stevenson and Jai Luthra.
- Diff unchanged.

Link to v1: https://lore.kernel.org/all/20260514193148.2357371-1-ingyujang25@korea.ac.kr/

 drivers/media/platform/raspberrypi/rp1-cfe/cfe.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/media/platform/raspberrypi/rp1-cfe/cfe.c b/drivers/media/platform/raspberrypi/rp1-cfe/cfe.c
index 8375ed3e97b9f..91e9fa0341e06 100644
--- a/drivers/media/platform/raspberrypi/rp1-cfe/cfe.c
+++ b/drivers/media/platform/raspberrypi/rp1-cfe/cfe.c
@@ -1779,7 +1779,7 @@ static int cfe_video_link_validate(struct media_link *link)
 		link->source->entity->name, link->source->index,
 		link->sink->entity->name, link->sink->index);
 
-	if (!media_entity_remote_source_pad_unique(link->sink->entity)) {
+	if (IS_ERR(media_entity_remote_source_pad_unique(link->sink->entity))) {
 		cfe_err(cfe, "video node %s pad not connected\n", vd->name);
 		return -ENOTCONN;
 	}
-- 
2.34.1