Hi Tomi
On Tue, Feb 28, 2023 at 11:23:46AM +0200, Tomi Valkeinen wrote:
> A common case with subdev routing is that on the subdevice just before
> the DMA engines (video nodes), no multiplexing is allowed on the source
> pads, as the DMA engine can only handle a single stream.
>
> In some other situations one might also want to do the same check on the
> sink side.
>
> Add new routing validation flags to check these:
> V4L2_SUBDEV_ROUTING_NO_SINK_MULTIPLEXING and
> V4L2_SUBDEV_ROUTING_NO_SOURCE_MULTIPLEXING.
>
> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@xxxxxxxxxxxxxxxx>
> ---
> drivers/media/v4l2-core/v4l2-subdev.c | 36 ++++++++++++++++++++++++---
> include/media/v4l2-subdev.h | 9 +++++++
> 2 files changed, 42 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c
> index bc3678337048..ae74a48dd2ba 100644
> --- a/drivers/media/v4l2-core/v4l2-subdev.c
> +++ b/drivers/media/v4l2-core/v4l2-subdev.c
> @@ -1664,7 +1664,8 @@ int v4l2_subdev_routing_validate(struct v4l2_subdev *sd,
> unsigned int i, j;
> int ret = -EINVAL;
>
> - if (disallow & V4L2_SUBDEV_ROUTING_NO_STREAM_MIX) {
> + if (disallow & (V4L2_SUBDEV_ROUTING_NO_STREAM_MIX |
> + V4L2_SUBDEV_ROUTING_NO_MULTIPLEXING)) {
> remote_pads = kcalloc(sd->entity.num_pads, sizeof(*remote_pads),
I wonder if we shoulnd't simply allocate the remote pads array and be
done with it.
Do we have maximum number of routes ? Can we even allocate statically ?
not strictly related to this patch though
> GFP_KERNEL);
> if (!remote_pads)
> @@ -1705,8 +1706,6 @@ int v4l2_subdev_routing_validate(struct v4l2_subdev *sd,
> i, "sink");
> goto out;
> }
> -
> - remote_pads[route->sink_pad] = route->source_pad;
> }
>
> /*
> @@ -1722,7 +1721,38 @@ int v4l2_subdev_routing_validate(struct v4l2_subdev *sd,
> i, "source");
> goto out;
> }
> + }
> +
> + /*
> + * V4L2_SUBDEV_ROUTING_NO_SINK_MULTIPLEXING: Pads on the sink
> + * side can not do stream multiplexing, i.e. there can be only
> + * a single stream in a sink pad.
> + */
> + if (disallow & V4L2_SUBDEV_ROUTING_NO_SINK_MULTIPLEXING) {
> + if (remote_pads[route->sink_pad] != U32_MAX) {
> + dev_dbg(sd->dev,
> + "route %u attempts to multiplex on %s pad %u\n",
> + i, "sink", route->sink_pad);
nit: in all this dev_dbg() there's no really need to specify "sink" or
"source" as arguments.
> + goto out;
> + }
> + }
>
> + /*
> + * V4L2_SUBDEV_ROUTING_NO_SOURCE_MULTIPLEXING: Pads on the
> + * source side can not do stream multiplexing, i.e. there can
> + * be only a single stream in a source pad.
> + */
> + if (disallow & V4L2_SUBDEV_ROUTING_NO_SOURCE_MULTIPLEXING) {
> + if (remote_pads[route->source_pad] != U32_MAX) {
> + dev_dbg(sd->dev,
> + "route %u attempts to multiplex on %s pad %u\n",
> + i, "source", route->source_pad);
> + goto out;
> + }
> + }
> +
> + if (remote_pads) {
> + remote_pads[route->sink_pad] = route->source_pad;
> remote_pads[route->source_pad] = route->sink_pad;
> }
>
> diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
> index a4331e0a5aeb..4a8d45e2c804 100644
> --- a/include/media/v4l2-subdev.h
> +++ b/include/media/v4l2-subdev.h
> @@ -1649,6 +1649,10 @@ u64 v4l2_subdev_state_xlate_streams(const struct v4l2_subdev_state *state,
> * @V4L2_SUBDEV_ROUTING_NO_SOURCE_STREAM_MIX:
> * streams on the same source pad may not be routed to streams on different
> * sink pads
> + * @V4L2_SUBDEV_ROUTING_NO_SOURCE_MULTIPLEXING:
> + * source pads may not contain multiplexed streams
> + * @V4L2_SUBDEV_ROUTING_NO_SINK_MULTIPLEXING:
> + * sink pads may not contain multiplexed streams
Again as a suggestion
* @V4L2_SUBDEV_ROUTING_NO_SOURCE_MULTIPLEXING:
* a single stream shall be routed to source pads
* @V4L2_SUBDEV_ROUTING_NO_SINK_MULTIPLEXING:
* a single stream shall originate from sink pads
> * @V4L2_SUBDEV_ROUTING_ONLY_1_TO_1:
> * only non-overlapping 1-to-1 stream routing is allowed (a combination of
> * @V4L2_SUBDEV_ROUTING_NO_1_TO_N and @V4L2_SUBDEV_ROUTING_NO_N_TO_1)
> @@ -1660,12 +1664,17 @@ enum v4l2_subdev_routing_restriction {
> V4L2_SUBDEV_ROUTING_NO_N_TO_1 = BIT(1),
> V4L2_SUBDEV_ROUTING_NO_SINK_STREAM_MIX = BIT(2),
> V4L2_SUBDEV_ROUTING_NO_SOURCE_STREAM_MIX = BIT(3),
> + V4L2_SUBDEV_ROUTING_NO_SINK_MULTIPLEXING = BIT(4),
> + V4L2_SUBDEV_ROUTING_NO_SOURCE_MULTIPLEXING = BIT(5),
> V4L2_SUBDEV_ROUTING_ONLY_1_TO_1 =
> V4L2_SUBDEV_ROUTING_NO_1_TO_N |
> V4L2_SUBDEV_ROUTING_NO_N_TO_1,
> V4L2_SUBDEV_ROUTING_NO_STREAM_MIX =
> V4L2_SUBDEV_ROUTING_NO_SINK_STREAM_MIX |
> V4L2_SUBDEV_ROUTING_NO_SOURCE_STREAM_MIX,
> + V4L2_SUBDEV_ROUTING_NO_MULTIPLEXING =
> + V4L2_SUBDEV_ROUTING_NO_SINK_MULTIPLEXING |
> + V4L2_SUBDEV_ROUTING_NO_SOURCE_MULTIPLEXING,
As you noticed alreayd this is missing doc
All nits/suggestions
Reviewed-by: Jacopo Mondi <jacopo.mondi@xxxxxxxxxxxxxxxx>
> };
>
> /**
> --
> 2.34.1
>
