[PATCH v2 04/17] media: v4l2-subdev: Allow releasing frame descriptors on return

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

Use DEFINE_FREE() to allow using __free() to release frame descriptors
using v4l2_subdev_free_frame_desc().

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
---
 include/media/v4l2-subdev.h | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
index e7127953ac22..c10ca3f5d979 100644
--- a/include/media/v4l2-subdev.h
+++ b/include/media/v4l2-subdev.h
@@ -1798,6 +1798,11 @@ int v4l2_subdev_get_frame_desc_passthrough(struct v4l2_subdev *sd,
  * for each frame descriptor obtained by calling this function using
  * v4l2_subdev_free_frame_desc().
  *
+ * Use __free() to release the frame descriptor automatically::
+ *
+ *    struct v4l2_mbus_frame_desc *desc __free(v4l2_subdev_free_frame_desc) =
+ *            v4l2_subdev_get_frame_desc(sd, pad, desc);
+ *
  * Return: The frame descriptor on success or a negative error code on failure.
  */
 struct v4l2_mbus_frame_desc *
@@ -1812,6 +1817,10 @@ v4l2_subdev_get_frame_desc(struct v4l2_subdev *sd, unsigned int pad,
  */
 void v4l2_subdev_free_frame_desc(struct v4l2_mbus_frame_desc *desc);
 
+DEFINE_FREE(v4l2_subdev_free_frame_desc, struct v4l2_mbus_frame_desc *, \
+	    if (!IS_ERR_OR_NULL(_T))					\
+		    v4l2_subdev_free_frame_desc(_T))
+
 #endif /* CONFIG_VIDEO_V4L2_SUBDEV_API */
 
 #endif /* CONFIG_MEDIA_CONTROLLER */
-- 
2.47.3