[PATCH v4 8/9] media: v4l: subdev: Return NULL from pad access functions on error

[Sakari Ailus <sakari.ailus@linux.intel.com>]

Return NULL from sub-device pad state access functions
(v4l2_subdev_state_get_{format,crop,compose}) for non-existent pads. While
this behaviour differs from older set of pad state information access
functions, we've had a WARN_ON() there for a long time and callers also do
validate the pad index nowadays. Therefore problems are not expected.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
---
 drivers/media/v4l2-core/v4l2-subdev.c | 18 +++---------------
 1 file changed, 3 insertions(+), 15 deletions(-)

diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c
index 9d4ff9b4fcec..bd0d89c2996f 100644
--- a/drivers/media/v4l2-core/v4l2-subdev.c
+++ b/drivers/media/v4l2-core/v4l2-subdev.c
@@ -1684,12 +1684,8 @@ __v4l2_subdev_state_get_format_stream(struct v4l2_subdev_state *state,
 		if (stream)
 			return NULL;
 
-		/*
-		 * Set the pad to 0 on error as this is aligned with the
-		 * behaviour of the pad state information access functions.
-		 */
 		if (WARN_ON(pad >= state->sd->entity.num_pads))
-			pad = 0;
+			return NULL;
 
 		return &state->pads[pad].try_fmt;
 	}
@@ -1722,12 +1718,8 @@ __v4l2_subdev_state_get_crop_stream(struct v4l2_subdev_state *state,
 		if (stream)
 			return NULL;
 
-		/*
-		 * Set the pad to 0 on error as this is aligned with the
-		 * behaviour of the pad state information access functions.
-		 */
 		if (WARN_ON(pad >= state->sd->entity.num_pads))
-			pad = 0;
+			return NULL;
 
 		return &state->pads[pad].try_crop;
 	}
@@ -1760,12 +1752,8 @@ __v4l2_subdev_state_get_compose_stream(struct v4l2_subdev_state *state,
 		if (stream)
 			return NULL;
 
-		/*
-		 * Set the pad to 0 on error as this is aligned with the
-		 * behaviour of the pad state information access functions.
-		 */
 		if (WARN_ON(pad >= state->sd->entity.num_pads))
-			pad = 0;
+			return NULL;
 
 		return &state->pads[pad].try_compose;
 	}
-- 
2.39.2