[v2,03/23] media: videobuf2-v4l2: Warn on holding buffers without support

Message ID 20220331193726.289559-4-nicolas.dufresne@collabora.com (mailing list archive)
State Superseded
Delegated to: Hans Verkuil
Headers
Series [v2,01/23] media: doc: Document dual use of H.264 pic_num/frame_num |

Commit Message

Nicolas Dufresne March 31, 2022, 7:37 p.m. UTC
  From: Sebastian Fricke <sebastian.fricke@collabora.com>

Using V4L2_BUF_FLAG_M2M_HOLD_CAPTURE_BUF flag without specifying the
subsystem flag VB2_V4L2_FL_SUPPORTS_M2M_HOLD_CAPTURE_BUF, results in
silently ignoring it.
Warn the user via a debug print when the flag is requested but ignored
by the videobuf2 framework.

Signed-off-by: Sebastian Fricke <sebastian.fricke@collabora.com>
Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
---
 drivers/media/common/videobuf2/videobuf2-v4l2.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)
  

Comments

Ezequiel Garcia April 2, 2022, 10:52 a.m. UTC | #1
On Thu, Mar 31, 2022 at 03:37:05PM -0400, Nicolas Dufresne wrote:
> From: Sebastian Fricke <sebastian.fricke@collabora.com>
> 
> Using V4L2_BUF_FLAG_M2M_HOLD_CAPTURE_BUF flag without specifying the
> subsystem flag VB2_V4L2_FL_SUPPORTS_M2M_HOLD_CAPTURE_BUF, results in
> silently ignoring it.
> Warn the user via a debug print when the flag is requested but ignored
> by the videobuf2 framework.
> 
> Signed-off-by: Sebastian Fricke <sebastian.fricke@collabora.com>
> Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>

Reviewed-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>

> ---
>  drivers/media/common/videobuf2/videobuf2-v4l2.c | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c
> index 6edf4508c636..812c8d1962e0 100644
> --- a/drivers/media/common/videobuf2/videobuf2-v4l2.c
> +++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c
> @@ -329,8 +329,13 @@ static int vb2_fill_vb2_v4l2_buffer(struct vb2_buffer *vb, struct v4l2_buffer *b
>  		 */
>  		vbuf->flags &= ~V4L2_BUF_FLAG_TIMECODE;
>  		vbuf->field = b->field;
> -		if (!(q->subsystem_flags & VB2_V4L2_FL_SUPPORTS_M2M_HOLD_CAPTURE_BUF))
> +		if (!(q->subsystem_flags & VB2_V4L2_FL_SUPPORTS_M2M_HOLD_CAPTURE_BUF)) {
> +			if (vbuf->flags & V4L2_BUF_FLAG_M2M_HOLD_CAPTURE_BUF)
> +				dprintk(q, 1,
> +					"Request holding buffer (%d), unsupported on output queue\n",
> +					b->index);
>  			vbuf->flags &= ~V4L2_BUF_FLAG_M2M_HOLD_CAPTURE_BUF;
> +		}
>  	} else {
>  		/* Zero any output buffer flags as this is a capture buffer */
>  		vbuf->flags &= ~V4L2_BUFFER_OUT_FLAGS;
> -- 
> 2.34.1
>
  

Patch

diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c
index 6edf4508c636..812c8d1962e0 100644
--- a/drivers/media/common/videobuf2/videobuf2-v4l2.c
+++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c
@@ -329,8 +329,13 @@  static int vb2_fill_vb2_v4l2_buffer(struct vb2_buffer *vb, struct v4l2_buffer *b
 		 */
 		vbuf->flags &= ~V4L2_BUF_FLAG_TIMECODE;
 		vbuf->field = b->field;
-		if (!(q->subsystem_flags & VB2_V4L2_FL_SUPPORTS_M2M_HOLD_CAPTURE_BUF))
+		if (!(q->subsystem_flags & VB2_V4L2_FL_SUPPORTS_M2M_HOLD_CAPTURE_BUF)) {
+			if (vbuf->flags & V4L2_BUF_FLAG_M2M_HOLD_CAPTURE_BUF)
+				dprintk(q, 1,
+					"Request holding buffer (%d), unsupported on output queue\n",
+					b->index);
 			vbuf->flags &= ~V4L2_BUF_FLAG_M2M_HOLD_CAPTURE_BUF;
+		}
 	} else {
 		/* Zero any output buffer flags as this is a capture buffer */
 		vbuf->flags &= ~V4L2_BUFFER_OUT_FLAGS;