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[v10,24/38] media: subdev: increase V4L2_FRAME_DESC_ENTRY_MAX to 8

Message ID 20211130141536.891878-25-tomi.valkeinen@ideasonboard.com
State Superseded
Headers show
Series v4l: subdev internal routing and streams | expand

Commit Message

Tomi Valkeinen Nov. 30, 2021, 2:15 p.m. UTC
V4L2_FRAME_DESC_ENTRY_MAX is currently set to 4. In theory it's possible
to have an arbitrary amount of streams in a single pad, so preferably
there should be no hardcoded maximum number.

However, I believe a reasonable max is 8, which would cover a CSI-2 pad
with 4 streams of pixel data and 4 streams of metadata.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
---
 include/media/v4l2-subdev.h | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

Comments

Jacopo Mondi Dec. 14, 2021, 8:35 a.m. UTC | #1
Hi Tomi

On Tue, Nov 30, 2021 at 04:15:22PM +0200, Tomi Valkeinen wrote:
> V4L2_FRAME_DESC_ENTRY_MAX is currently set to 4. In theory it's possible
> to have an arbitrary amount of streams in a single pad, so preferably
> there should be no hardcoded maximum number.
>
> However, I believe a reasonable max is 8, which would cover a CSI-2 pad
> with 4 streams of pixel data and 4 streams of metadata.
>
> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> Reviewed-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

If I'm not mistaken C-PHY supports up to 32 virtual channels ?

Can be increased later...

Reviewed-by: Jacopo Mondi <jacopo+renesas@jmondi.org>

Thanks
  j

> ---
>  include/media/v4l2-subdev.h | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
> index 2921885eb390..a82fc74f4646 100644
> --- a/include/media/v4l2-subdev.h
> +++ b/include/media/v4l2-subdev.h
> @@ -360,7 +360,11 @@ struct v4l2_mbus_frame_desc_entry {
>  	} bus;
>  };
>
> -#define V4L2_FRAME_DESC_ENTRY_MAX	4
> + /*
> +  * FIXME: If this number is too small, it should be dropped altogether and the
> +  * API switched to a dynamic number of frame descriptor entries.
> +  */
> +#define V4L2_FRAME_DESC_ENTRY_MAX	8
>
>  /**
>   * enum v4l2_mbus_frame_desc_type - media bus frame description type
> --
> 2.25.1
>
diff mbox series

Patch

diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
index 2921885eb390..a82fc74f4646 100644
--- a/include/media/v4l2-subdev.h
+++ b/include/media/v4l2-subdev.h
@@ -360,7 +360,11 @@  struct v4l2_mbus_frame_desc_entry {
 	} bus;
 };
 
-#define V4L2_FRAME_DESC_ENTRY_MAX	4
+ /*
+  * FIXME: If this number is too small, it should be dropped altogether and the
+  * API switched to a dynamic number of frame descriptor entries.
+  */
+#define V4L2_FRAME_DESC_ENTRY_MAX	8
 
 /**
  * enum v4l2_mbus_frame_desc_type - media bus frame description type