diff mbox series

[3/3] media: rcar-{csi2,vin}: Move to full Virtual Channel routing per CSI-2 IP

Message ID 20211020200225.1956048-4-niklas.soderlund+renesas@ragnatech.se (mailing list archive)
State New, archived
Headers show
Series media: rcar-{csi2,vin}: Move to full Virtual Channel routing per CSI-2 IP | expand

Commit Message

Niklas Söderlund Oct. 20, 2021, 8:02 p.m. UTC
When Gen3 support was first added to this R-Car VIN and CSI-2 driver the
routing was centred around the CHSEL register which multiplex the
different parallel buses that sits between the CSI-2 receivers source
side and the VIN dma engines. This was a bad design as the multiplexing
do allow for only a few combinations and do not play nice with many
video streams in the system.

For example it's only possible for CSI-2 Virtual Channels 0 and 1 of any
given CSI-2 receiver to be used together with the scaler.

Later datasheets have expanded the documentation and it is now possible
to improve on this design by allowing any Virtual Channel to be routed
to any R-Car VIN instance, provided that there exists a parallel bus
between them. This increases the flexibility as all Virtual Channels can
now be used together with the scaler for example.

The redesign is not however perfect. While the new design allows for
many more routes, two constrains limit a small portion of routes that
was possible in the old design but are no more.

- It is no longer possible to route the same CSI-2 and VC to more then
  one VIN at a time. This was theoretically possible before if the
  specific SoC allowed for the same CSI-2 and VC to be routed to two
  different VIN capture groups.

- It is no longer possible to simultaneously mix links from two CSI-2 IP
  blocks to the same VIN capture group.

  For example if VIN2 is capturing from CSI40 then VIN{0,1,3} must also
  capture from CSI40. While VIN{4,5,6,7} is still free to capture from
  any other CSI-2 IP in the system. Once all VIN{0,1,2,3} links to CSI40
  are disabled that VIN capture group is free again to capture from any
  other CSI-2 IP it is connected to.

At the core of the redesign is greater cooperator of the R-Car VIN and
CSI-2 drivers in configuring the routing. The VIN driver is after this
change only responsible to configure the full VIN capture groups
parallel buses to be to a particular CSI-2 IP. While the configuration
of which CSI-2 Virtual Channel is outputted on which of the R-Car CSI-2
IP output ports is handled by the CSI-2 driver.

Before this change the CSI-2 Virtual Channel to output port was static
in the CSI-2 driver and the different links only manipulated the VIN
capture groups CHSEL register. With this change both the CHSEl register
and the CSI-2 routing VCDT registers are modified for greater
flexibility.

This change touches both the R-Car VIN and R-Car CSI-2 drivers in the
same commit as both drivers cooperate closely and one change without the
other would more or less break video capture.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
---
 drivers/media/platform/rcar-vin/rcar-core.c | 318 +++++---------------
 drivers/media/platform/rcar-vin/rcar-csi2.c |  58 +++-
 drivers/media/platform/rcar-vin/rcar-dma.c  |   2 +-
 drivers/media/platform/rcar-vin/rcar-vin.h  |  18 +-
 4 files changed, 136 insertions(+), 260 deletions(-)

Comments

Jacopo Mondi Nov. 4, 2021, 5:29 p.m. UTC | #1
Hi Niklas,

On Wed, Oct 20, 2021 at 10:02:25PM +0200, Niklas Söderlund wrote:
> When Gen3 support was first added to this R-Car VIN and CSI-2 driver the
> routing was centred around the CHSEL register which multiplex the

multiplexes

> different parallel buses that sits between the CSI-2 receivers source

buses -> sit

> side and the VIN dma engines. This was a bad design as the multiplexing
> do allow for only a few combinations and do not play nice with many
> video streams in the system.
>
> For example it's only possible for CSI-2 Virtual Channels 0 and 1 of any
> given CSI-2 receiver to be used together with the scaler.
>
> Later datasheets have expanded the documentation and it is now possible
> to improve on this design by allowing any Virtual Channel to be routed
> to any R-Car VIN instance, provided that there exists a parallel bus
> between them. This increases the flexibility as all Virtual Channels can
> now be used together with the scaler for example.
>
> The redesign is not however perfect. While the new design allows for
> many more routes, two constrains limit a small portion of routes that
> was possible in the old design but are no more.
>
> - It is no longer possible to route the same CSI-2 and VC to more then
>   one VIN at a time. This was theoretically possible before if the
>   specific SoC allowed for the same CSI-2 and VC to be routed to two
>   different VIN capture groups.

I think that's acceptable

>
> - It is no longer possible to simultaneously mix links from two CSI-2 IP
>   blocks to the same VIN capture group.

This one is a little bit bothering but I don't see it as a huge blocker
personally.

>
>   For example if VIN2 is capturing from CSI40 then VIN{0,1,3} must also
>   capture from CSI40. While VIN{4,5,6,7} is still free to capture from
>   any other CSI-2 IP in the system. Once all VIN{0,1,2,3} links to CSI40
>   are disabled that VIN capture group is free again to capture from any
>   other CSI-2 IP it is connected to.
>
> At the core of the redesign is greater cooperator of the R-Car VIN and
> CSI-2 drivers in configuring the routing. The VIN driver is after this
> change only responsible to configure the full VIN capture groups
> parallel buses to be to a particular CSI-2 IP. While the configuration
> of which CSI-2 Virtual Channel is outputted on which of the R-Car CSI-2
> IP output ports is handled by the CSI-2 driver.
>
> Before this change the CSI-2 Virtual Channel to output port was static
> in the CSI-2 driver and the different links only manipulated the VIN
> capture groups CHSEL register. With this change both the CHSEl register
> and the CSI-2 routing VCDT registers are modified for greater
> flexibility.
>
> This change touches both the R-Car VIN and R-Car CSI-2 drivers in the
> same commit as both drivers cooperate closely and one change without the
> other would more or less break video capture.
>
> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> ---
>  drivers/media/platform/rcar-vin/rcar-core.c | 318 +++++---------------
>  drivers/media/platform/rcar-vin/rcar-csi2.c |  58 +++-
>  drivers/media/platform/rcar-vin/rcar-dma.c  |   2 +-
>  drivers/media/platform/rcar-vin/rcar-vin.h  |  18 +-
>  4 files changed, 136 insertions(+), 260 deletions(-)
>
> diff --git a/drivers/media/platform/rcar-vin/rcar-core.c b/drivers/media/platform/rcar-vin/rcar-core.c
> index 65ab66a072e9d635..6b05ad10e8aa66f9 100644
> --- a/drivers/media/platform/rcar-vin/rcar-core.c
> +++ b/drivers/media/platform/rcar-vin/rcar-core.c
> @@ -745,27 +745,6 @@ static int rvin_parallel_init(struct rvin_dev *vin)
>   * CSI-2
>   */
>
> -static unsigned int rvin_csi2_get_mask(struct rvin_dev *vin,
> -				       enum rvin_csi_id csi_id,
> -				       unsigned char channel)
> -{
> -	const struct rvin_group_route *route;
> -	unsigned int mask = 0;
> -
> -	for (route = vin->info->routes; route->mask; route++) {
> -		if (route->vin == vin->id &&
> -		    route->csi == csi_id &&
> -		    route->channel == channel) {
> -			vin_dbg(vin,
> -				"Adding route: vin: %d csi: %d channel: %d\n",
> -				route->vin, route->csi, route->channel);
> -			mask |= route->mask;
> -		}
> -	}
> -
> -	return mask;
> -}
> -
>  /*
>   * Link setup for the links between a VIN and a CSI-2 receiver is a bit
>   * complex. The reason for this is that the register controlling routing
> @@ -852,9 +831,9 @@ static int rvin_csi2_link_notify(struct media_link *link, u32 flags,
>  			link->source->entity->name);
>  		ret = -ENODEV;
>  	} else {
> -		unsigned int master_id, channel, mask_new;
> -		unsigned int mask = ~0;
> -		struct media_pad *csi_pad;
> +		const struct rvin_group_route *route;
> +		unsigned int chsel = -1;
> +		unsigned int master_id;
>
>  		master_id = rvin_group_id_to_master(vin->id);
>
> @@ -863,8 +842,10 @@ static int rvin_csi2_link_notify(struct media_link *link, u32 flags,
>  			goto out;
>  		}
>
> -		/* Build a mask for already enabled links. */
> +		/* Make sure group is connected to same CSI-2 */
>  		for (i = master_id; i < master_id + 4; i++) {
> +			struct media_pad *csi_pad;
> +
>  			if (!group->vin[i])
>  				continue;

Are you sure this checks for all VINs in the group to be connected to
the same CSI-2 receiver ? The loop goes one as

		/* Make sure group is connected to same CSI-2 */
		for (i = master_id; i < master_id + 4; i++) {
			struct media_pad *csi_pad;

			if (!group->vin[i])
				continue;

			/* Get remote CSI-2, if any. */
			csi_pad = media_entity_remote_pad(
					&group->vin[i]->vdev.entity.pads[0]);
			if (!csi_pad)
				continue;

			if (csi_pad->entity != link->source->entity) {
				vin_dbg(vin, "Already attached to %s\n",
					csi_pad->entity->name);
				ret = -EBUSY;
				goto out;
			}
		}

Which if I got it right verifies that entity at the other end of the
link is the same as the link's source entity, which seems to be a
tautology to me, am I wrong ?

Shouldn't you

        struct media_entity *csi2 = nullptr;
        for (i = master_id; i < master_id + 4; i++) {
                struct media_pad *csi_pad;

                if (!group->vin[i])
                        continue;

                csi_pad = media_entity_remote_pad(
                                &group->vin[i]->vdev.entity.pads[0]);

                if (!csi2) {
                        csi2 = csi_pad->entity;
                        continue;
                }

                if (csi2 != csi2_pad->entity)
                        return -EINVAL;

        }

>
> @@ -874,26 +855,24 @@ static int rvin_csi2_link_notify(struct media_link *link, u32 flags,
>  			if (!csi_pad)
>  				continue;
>
> -			csi_id = rvin_group_entity_to_remote_id(group,
> -								csi_pad->entity);
> -			channel = rvin_group_csi_pad_to_channel(csi_pad->index);
> -
> -			mask &= rvin_csi2_get_mask(group->vin[i], csi_id, channel);
> +			if (csi_pad->entity != link->source->entity) {
> +				vin_dbg(vin, "Already attached to %s\n",
> +					csi_pad->entity->name);
> +				ret = -EBUSY;
> +				goto out;
> +			}
>  		}
>
> -		channel = rvin_group_csi_pad_to_channel(link->source->index);
> -		mask_new = mask & rvin_csi2_get_mask(vin, csi_id, channel);
> -		vin_dbg(vin, "Try link change mask: 0x%x new: 0x%x\n", mask,
> -			mask_new);
> -
> -		if (!mask_new) {
> -			ret = -EMLINK;
> -			goto out;
> +		for (route = vin->info->routes; route->chsel; route++) {
> +			if (route->master == master_id && route->csi == csi_id) {
> +				chsel = route->chsel;
> +				break;
> +			}
>  		}
>
> -		/* New valid CHSEL found, set the new value. */
> -		ret = rvin_set_channel_routing(group->vin[master_id],
> -					       __ffs(mask_new));
> +		BUG_ON(chsel < 0);
> +
> +		ret = rvin_set_channel_routing(group->vin[master_id], chsel);
>  		if (ret)
>  			goto out;
>
> @@ -909,46 +888,59 @@ static const struct media_device_ops rvin_csi2_media_ops = {
>  	.link_notify = rvin_csi2_link_notify,
>  };
>
> -static int rvin_csi2_add_route(struct rvin_group *group,
> -			       const struct rvin_group_route *route)
> +static int rvin_csi2_add_routes(struct rvin_group *group, unsigned int id,
> +				const struct rvin_group_route *route)
>
>  {
>  	struct media_entity *source = &group->remotes[route->csi].subdev->entity;
> -	unsigned int source_idx = rvin_group_csi_channel_to_pad(route->channel);
> -	struct media_entity *sink = &group->vin[route->vin]->vdev.entity;
> -	struct media_pad *source_pad = &source->pads[source_idx];
> +	struct media_entity *sink = &group->vin[id]->vdev.entity;
>  	struct media_pad *sink_pad = &sink->pads[0];
> +	unsigned int channel;
> +	int ret;
>
> -	if (media_entity_find_link(source_pad, sink_pad))
> -		return 0;
> +	for (channel = 0; channel < 4; channel++) {
> +		unsigned int source_idx = rvin_group_csi_channel_to_pad(channel);
> +		struct media_pad *source_pad = &source->pads[source_idx];
>
> -	return media_create_pad_link(source, source_idx, sink, 0, 0);
> +		if (media_entity_find_link(source_pad, sink_pad))
> +			continue;
> +
> +		ret = media_create_pad_link(source, source_idx, sink, 0, 0);
> +		if (ret)
> +			return ret;
> +	}
> +
> +	return 0;
>  }
>
>  static int rvin_csi2_setup_links(struct rvin_dev *vin)
>  {
>  	const struct rvin_group_route *route;
> +	unsigned int id;
>  	int ret = -EINVAL;
>
>  	/* Create all media device links between VINs and CSI-2's. */
>  	mutex_lock(&vin->group->lock);
> -	for (route = vin->info->routes; route->mask; route++) {
> -		/* Check that VIN is part of the group. */
> -		if (!vin->group->vin[route->vin])
> -			continue;
> -
> +	for (route = vin->info->routes; route->chsel; route++) {
>  		/* Check that VIN' master is part of the group. */
> -		if (!vin->group->vin[rvin_group_id_to_master(route->vin)])
> +		if (!vin->group->vin[route->master])
>  			continue;
>
>  		/* Check that CSI-2 is part of the group. */
>  		if (!vin->group->remotes[route->csi].subdev)
>  			continue;
>
> -		ret = rvin_csi2_add_route(vin->group, route);
> -		if (ret)
> -			break;
> +		for (id = route->master; id < route->master + 4; id++) {
> +			/* Check that VIN is part of the group. */
> +			if (!vin->group->vin[id])
> +				continue;
> +
> +			ret = rvin_csi2_add_routes(vin->group, id, route);
> +			if (ret)
> +				goto out;
> +		}
>  	}
> +out:
>  	mutex_unlock(&vin->group->lock);
>
>  	return ret;
> @@ -1158,30 +1150,9 @@ static const struct rvin_info rcar_info_gen2 = {
>  };
>
>  static const struct rvin_group_route rcar_info_r8a774e1_routes[] = {
> -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 0, .mask = BIT(0) | BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 0, .mask = BIT(1) | BIT(4) },
> -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 0, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 1, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 1, .mask = BIT(1) | BIT(3) },
> -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 1, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 1, .mask = BIT(4) },
> -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 2, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 2, .mask = BIT(1) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 2, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI40, .channel = 2, .vin = 2, .mask = BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 2, .vin = 2, .mask = BIT(4) },
> -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 3, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 3, .mask = BIT(1) | BIT(2) },
> -	{ .csi = RVIN_CSI40, .channel = 3, .vin = 3, .mask = BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 3, .vin = 3, .mask = BIT(4) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 4, .mask = BIT(1) | BIT(4) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 5, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 5, .mask = BIT(4) },
> -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 6, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 6, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI20, .channel = 2, .vin = 6, .mask = BIT(4) },
> -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 7, .mask = BIT(1) | BIT(2) },
> -	{ .csi = RVIN_CSI20, .channel = 3, .vin = 7, .mask = BIT(4) },
> +	{ .master = 0, .csi = RVIN_CSI20, .chsel = 0x04 },
> +	{ .master = 0, .csi = RVIN_CSI40, .chsel = 0x03 },
> +	{ .master = 4, .csi = RVIN_CSI20, .chsel = 0x04 },
>  	{ /* Sentinel */ }
>  };
>
> @@ -1194,38 +1165,10 @@ static const struct rvin_info rcar_info_r8a774e1 = {
>  };
>
>  static const struct rvin_group_route rcar_info_r8a7795_routes[] = {
> -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 0, .mask = BIT(0) | BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 0, .mask = BIT(1) | BIT(4) },
> -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 0, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 1, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 1, .mask = BIT(1) | BIT(3) },
> -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 1, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 1, .mask = BIT(4) },
> -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 2, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 2, .mask = BIT(1) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 2, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI40, .channel = 2, .vin = 2, .mask = BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 2, .vin = 2, .mask = BIT(4) },
> -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 3, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 3, .mask = BIT(1) | BIT(2) },
> -	{ .csi = RVIN_CSI40, .channel = 3, .vin = 3, .mask = BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 3, .vin = 3, .mask = BIT(4) },
> -	{ .csi = RVIN_CSI41, .channel = 0, .vin = 4, .mask = BIT(0) | BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 4, .mask = BIT(1) | BIT(4) },
> -	{ .csi = RVIN_CSI41, .channel = 1, .vin = 4, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 5, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI41, .channel = 1, .vin = 5, .mask = BIT(1) | BIT(3) },
> -	{ .csi = RVIN_CSI41, .channel = 0, .vin = 5, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 5, .mask = BIT(4) },
> -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 6, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI41, .channel = 0, .vin = 6, .mask = BIT(1) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 6, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI41, .channel = 2, .vin = 6, .mask = BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 2, .vin = 6, .mask = BIT(4) },
> -	{ .csi = RVIN_CSI41, .channel = 1, .vin = 7, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 7, .mask = BIT(1) | BIT(2) },
> -	{ .csi = RVIN_CSI41, .channel = 3, .vin = 7, .mask = BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 3, .vin = 7, .mask = BIT(4) },
> +	{ .master = 0, .csi = RVIN_CSI20, .chsel = 0x04 },
> +	{ .master = 0, .csi = RVIN_CSI40, .chsel = 0x03 },
> +	{ .master = 4, .csi = RVIN_CSI20, .chsel = 0x04 },
> +	{ .master = 4, .csi = RVIN_CSI41, .chsel = 0x03 },
>  	{ /* Sentinel */ }
>  };
>
> @@ -1239,48 +1182,12 @@ static const struct rvin_info rcar_info_r8a7795 = {
>  };
>
>  static const struct rvin_group_route rcar_info_r8a7795es1_routes[] = {
> -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 0, .mask = BIT(0) | BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 0, .mask = BIT(1) | BIT(4) },
> -	{ .csi = RVIN_CSI21, .channel = 0, .vin = 0, .mask = BIT(2) | BIT(5) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 1, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI21, .channel = 0, .vin = 1, .mask = BIT(1) },
> -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 1, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 1, .mask = BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 1, .mask = BIT(4) },
> -	{ .csi = RVIN_CSI21, .channel = 1, .vin = 1, .mask = BIT(5) },
> -	{ .csi = RVIN_CSI21, .channel = 0, .vin = 2, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 2, .mask = BIT(1) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 2, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI40, .channel = 2, .vin = 2, .mask = BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 2, .vin = 2, .mask = BIT(4) },
> -	{ .csi = RVIN_CSI21, .channel = 2, .vin = 2, .mask = BIT(5) },
> -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 3, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 3, .mask = BIT(1) },
> -	{ .csi = RVIN_CSI21, .channel = 1, .vin = 3, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI40, .channel = 3, .vin = 3, .mask = BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 3, .vin = 3, .mask = BIT(4) },
> -	{ .csi = RVIN_CSI21, .channel = 3, .vin = 3, .mask = BIT(5) },
> -	{ .csi = RVIN_CSI41, .channel = 0, .vin = 4, .mask = BIT(0) | BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 4, .mask = BIT(1) | BIT(4) },
> -	{ .csi = RVIN_CSI21, .channel = 0, .vin = 4, .mask = BIT(2) | BIT(5) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 5, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI21, .channel = 0, .vin = 5, .mask = BIT(1) },
> -	{ .csi = RVIN_CSI41, .channel = 0, .vin = 5, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI41, .channel = 1, .vin = 5, .mask = BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 5, .mask = BIT(4) },
> -	{ .csi = RVIN_CSI21, .channel = 1, .vin = 5, .mask = BIT(5) },
> -	{ .csi = RVIN_CSI21, .channel = 0, .vin = 6, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI41, .channel = 0, .vin = 6, .mask = BIT(1) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 6, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI41, .channel = 2, .vin = 6, .mask = BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 2, .vin = 6, .mask = BIT(4) },
> -	{ .csi = RVIN_CSI21, .channel = 2, .vin = 6, .mask = BIT(5) },
> -	{ .csi = RVIN_CSI41, .channel = 1, .vin = 7, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 7, .mask = BIT(1) },
> -	{ .csi = RVIN_CSI21, .channel = 1, .vin = 7, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI41, .channel = 3, .vin = 7, .mask = BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 3, .vin = 7, .mask = BIT(4) },
> -	{ .csi = RVIN_CSI21, .channel = 3, .vin = 7, .mask = BIT(5) },
> +	{ .master = 0, .csi = RVIN_CSI20, .chsel = 0x04 },
> +	{ .master = 0, .csi = RVIN_CSI20, .chsel = 0x05 },
> +	{ .master = 0, .csi = RVIN_CSI40, .chsel = 0x03 },
> +	{ .master = 4, .csi = RVIN_CSI20, .chsel = 0x04 },
> +	{ .master = 4, .csi = RVIN_CSI20, .chsel = 0x05 },
> +	{ .master = 4, .csi = RVIN_CSI40, .chsel = 0x03 },

This is really bothering, as otherwise in all other routes

        .csi == RVIN_CSI4x -> chsel = 0x03
        .csi == RVIN_CSI2x -> chsel = 0x04

>  	{ /* Sentinel */ }
>  };
>
> @@ -1293,34 +1200,10 @@ static const struct rvin_info rcar_info_r8a7795es1 = {
>  };
>
>  static const struct rvin_group_route rcar_info_r8a7796_routes[] = {
> -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 0, .mask = BIT(0) | BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 0, .mask = BIT(1) | BIT(4) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 1, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 1, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 1, .mask = BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 1, .mask = BIT(4) },
> -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 2, .mask = BIT(1) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 2, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI40, .channel = 2, .vin = 2, .mask = BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 2, .vin = 2, .mask = BIT(4) },
> -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 3, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 3, .mask = BIT(1) },
> -	{ .csi = RVIN_CSI40, .channel = 3, .vin = 3, .mask = BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 3, .vin = 3, .mask = BIT(4) },
> -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 4, .mask = BIT(0) | BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 4, .mask = BIT(1) | BIT(4) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 5, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 5, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 5, .mask = BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 5, .mask = BIT(4) },
> -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 6, .mask = BIT(1) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 6, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI40, .channel = 2, .vin = 6, .mask = BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 2, .vin = 6, .mask = BIT(4) },
> -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 7, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 7, .mask = BIT(1) },
> -	{ .csi = RVIN_CSI40, .channel = 3, .vin = 7, .mask = BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 3, .vin = 7, .mask = BIT(4) },
> +	{ .master = 0, .csi = RVIN_CSI20, .chsel = 0x04 },
> +	{ .master = 0, .csi = RVIN_CSI40, .chsel = 0x03 },
> +	{ .master = 4, .csi = RVIN_CSI20, .chsel = 0x04 },
> +	{ .master = 4, .csi = RVIN_CSI40, .chsel = 0x03 },
>  	{ /* Sentinel */ }
>  };
>
> @@ -1334,38 +1217,10 @@ static const struct rvin_info rcar_info_r8a7796 = {
>  };
>
>  static const struct rvin_group_route rcar_info_r8a77965_routes[] = {
> -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 0, .mask = BIT(0) | BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 0, .mask = BIT(1) | BIT(4) },
> -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 0, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 1, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 1, .mask = BIT(1) | BIT(3) },
> -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 1, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 1, .mask = BIT(4) },
> -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 2, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 2, .mask = BIT(1) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 2, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI40, .channel = 2, .vin = 2, .mask = BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 2, .vin = 2, .mask = BIT(4) },
> -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 3, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 3, .mask = BIT(1) | BIT(2) },
> -	{ .csi = RVIN_CSI40, .channel = 3, .vin = 3, .mask = BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 3, .vin = 3, .mask = BIT(4) },
> -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 4, .mask = BIT(0) | BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 4, .mask = BIT(1) | BIT(4) },
> -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 4, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 5, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 5, .mask = BIT(1) | BIT(3) },
> -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 5, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 5, .mask = BIT(4) },
> -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 6, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 6, .mask = BIT(1) },
> -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 6, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI40, .channel = 2, .vin = 6, .mask = BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 2, .vin = 6, .mask = BIT(4) },
> -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 7, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 7, .mask = BIT(1) | BIT(2) },
> -	{ .csi = RVIN_CSI40, .channel = 3, .vin = 7, .mask = BIT(3) },
> -	{ .csi = RVIN_CSI20, .channel = 3, .vin = 7, .mask = BIT(4) },
> +	{ .master = 0, .csi = RVIN_CSI20, .chsel = 0x04 },
> +	{ .master = 0, .csi = RVIN_CSI40, .chsel = 0x03 },
> +	{ .master = 4, .csi = RVIN_CSI20, .chsel = 0x04 },
> +	{ .master = 4, .csi = RVIN_CSI40, .chsel = 0x03 },
>  	{ /* Sentinel */ }
>  };
>
> @@ -1379,13 +1234,7 @@ static const struct rvin_info rcar_info_r8a77965 = {
>  };
>
>  static const struct rvin_group_route rcar_info_r8a77970_routes[] = {
> -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 0, .mask = BIT(0) | BIT(3) },
> -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 1, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 1, .mask = BIT(3) },
> -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 2, .mask = BIT(1) },
> -	{ .csi = RVIN_CSI40, .channel = 2, .vin = 2, .mask = BIT(3) },
> -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 3, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI40, .channel = 3, .vin = 3, .mask = BIT(3) },
> +	{ .master = 0, .csi = RVIN_CSI40, .chsel = 0x03 },
>  	{ /* Sentinel */ }
>  };
>
> @@ -1398,22 +1247,8 @@ static const struct rvin_info rcar_info_r8a77970 = {
>  };
>
>  static const struct rvin_group_route rcar_info_r8a77980_routes[] = {
> -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 0, .mask = BIT(0) | BIT(3) },
> -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 0, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 1, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 1, .mask = BIT(1) | BIT(3) },
> -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 2, .mask = BIT(1) },
> -	{ .csi = RVIN_CSI40, .channel = 2, .vin = 2, .mask = BIT(3) },
> -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 3, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI40, .channel = 3, .vin = 3, .mask = BIT(3) },
> -	{ .csi = RVIN_CSI41, .channel = 0, .vin = 4, .mask = BIT(0) | BIT(3) },
> -	{ .csi = RVIN_CSI41, .channel = 1, .vin = 4, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI41, .channel = 0, .vin = 5, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI41, .channel = 1, .vin = 5, .mask = BIT(1) | BIT(3) },
> -	{ .csi = RVIN_CSI41, .channel = 0, .vin = 6, .mask = BIT(1) },
> -	{ .csi = RVIN_CSI41, .channel = 2, .vin = 6, .mask = BIT(3) },
> -	{ .csi = RVIN_CSI41, .channel = 1, .vin = 7, .mask = BIT(0) },
> -	{ .csi = RVIN_CSI41, .channel = 3, .vin = 7, .mask = BIT(3) },
> +	{ .master = 0, .csi = RVIN_CSI40, .chsel = 0x03 },
> +	{ .master = 4, .csi = RVIN_CSI41, .chsel = 0x03 },
>  	{ /* Sentinel */ }
>  };
>
> @@ -1427,10 +1262,7 @@ static const struct rvin_info rcar_info_r8a77980 = {
>  };
>
>  static const struct rvin_group_route rcar_info_r8a77990_routes[] = {
> -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 4, .mask = BIT(0) | BIT(3) },
> -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 5, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 4, .mask = BIT(2) },
> -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 5, .mask = BIT(1) | BIT(3) },
> +	{ .master = 0, .csi = RVIN_CSI40, .chsel = 0x03 },
>  	{ /* Sentinel */ }
>  };
>
> diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c b/drivers/media/platform/rcar-vin/rcar-csi2.c
> index 11848d0c4a55cb4c..b8c56d248454efbf 100644
> --- a/drivers/media/platform/rcar-vin/rcar-csi2.c
> +++ b/drivers/media/platform/rcar-vin/rcar-csi2.c
> @@ -468,6 +468,8 @@ struct rcar_csi2 {
>  	struct v4l2_subdev *remote;
>  	unsigned int remote_pad;
>
> +	int channel_vc[4];
> +
>  	struct mutex lock; /* Protects mf and stream_count. */
>  	struct v4l2_mbus_framefmt mf;
>  	int stream_count;
> @@ -664,8 +666,11 @@ static int rcsi2_start_receiver(struct rcar_csi2 *priv)
>  	for (i = 0; i < priv->info->num_channels; i++) {
>  		u32 vcdt_part;
>
> -		vcdt_part = VCDT_SEL_VC(i) | VCDT_VCDTN_EN | VCDT_SEL_DTN_ON |
> -			VCDT_SEL_DT(format->datatype);
> +		if (priv->channel_vc[i] < 0)
> +			continue;
> +
> +		vcdt_part = VCDT_SEL_VC(priv->channel_vc[i]) | VCDT_VCDTN_EN |
> +			VCDT_SEL_DTN_ON | VCDT_SEL_DT(format->datatype);
>
>  		/* Store in correct reg and offset. */
>  		if (i < 2)
> @@ -1240,7 +1245,53 @@ static int rcsi2_init_phtw_v3u(struct rcar_csi2 *priv,
>   * Platform Device Driver.
>   */
>
> +static int rcsi2_link_setup(struct media_entity *entity,
> +			    const struct media_pad *local,
> +			    const struct media_pad *remote, u32 flags)
> +{
> +	struct v4l2_subdev *sd = media_entity_to_v4l2_subdev(entity);
> +	struct rcar_csi2 *priv = sd_to_csi2(sd);
> +	struct video_device *vdev;
> +	int channel, vc;
> +	u32 id;
> +
> +	if (!is_media_entity_v4l2_video_device(remote->entity)) {

Can this happen ?

> +		dev_err(priv->dev, "Remote is not a video device\n");
> +		return -EINVAL;
> +	}
> +
> +	vdev = media_entity_to_video_device(remote->entity);
> +
> +	if (of_property_read_u32(vdev->dev_parent->of_node, "renesas,id", &id)) {

Reading properties from a remote device node usually makes people
scream but I understand the purpose here and it doesn't sound -that-
bad

> +		dev_err(priv->dev, "No renesas,id, can't configure routing\n");
> +		return -EINVAL;
> +	}

Ouch, I take back my initial assumption that is harmless to not being
able anymore to capture the same VC from multiple VIN, in particular
in regards to embedded data.

CHSEL[3] allows to select if a specific VC or "CSI-2 embedded data
of Virtual Channel 0" has to be captured. This setup prevents to
output on two channels VC0 and filter out embedded data if I'm not
mistaken...

> +
> +	channel = id % 4;
> +
> +	if (flags & MEDIA_LNK_FL_ENABLED) {
> +		if (media_entity_remote_pad(local)) {
> +			dev_dbg(priv->dev,
> +				"Each VC can only be routed to one output channel\n");

Can this limitation be lifted to support capturing embedded data from
VC0 ? That would require mixing media links and formats though :(

> +			return -EINVAL;
> +		}
> +
> +		vc = local->index - 1;
> +
> +		dev_dbg(priv->dev, "Route VC%d to VIN%u on output channel %d\n",
> +			vc, id, channel);
> +	} else {
> +		vc = -1;
> +	}
> +
> +	priv->channel_vc[channel] = vc;
> +
> +	return 0;
> +}
> +
> +
>  static const struct media_entity_operations rcar_csi2_entity_ops = {
> +	.link_setup = rcsi2_link_setup,
>  	.link_validate = v4l2_subdev_link_validate,
>  };
>
> @@ -1459,6 +1510,9 @@ static int rcsi2_probe(struct platform_device *pdev)
>  	if (ret)
>  		goto error_async;
>
> +	for (i = 0; i < ARRAY_SIZE(priv->channel_vc); i++)
> +		priv->channel_vc[i] = -1;
> +
>  	pm_runtime_enable(&pdev->dev);
>
>  	ret = v4l2_async_register_subdev(&priv->subdev);
> diff --git a/drivers/media/platform/rcar-vin/rcar-dma.c b/drivers/media/platform/rcar-vin/rcar-dma.c
> index 25ead9333d0046e7..b72ae27a407dc96c 100644
> --- a/drivers/media/platform/rcar-vin/rcar-dma.c
> +++ b/drivers/media/platform/rcar-vin/rcar-dma.c
> @@ -1490,7 +1490,7 @@ int rvin_set_channel_routing(struct rvin_dev *vin, u8 chsel)
>  	 * register. IFMD_DES1 controls data expansion mode for CSI20/21,
>  	 * IFMD_DES0 controls data expansion mode for CSI40/41.
>  	 */
> -	for (route = vin->info->routes; route->mask; route++) {
> +	for (route = vin->info->routes; route->chsel; route++) {
>  		if (route->csi == RVIN_CSI20 || route->csi == RVIN_CSI21)
>  			ifmd |= VNCSI_IFMD_DES1;
>  		else
> diff --git a/drivers/media/platform/rcar-vin/rcar-vin.h b/drivers/media/platform/rcar-vin/rcar-vin.h
> index 6c06320174a2ed96..ddc1830be9a5d6c3 100644
> --- a/drivers/media/platform/rcar-vin/rcar-vin.h
> +++ b/drivers/media/platform/rcar-vin/rcar-vin.h
> @@ -128,11 +128,9 @@ struct rvin_parallel_entity {
>   * struct rvin_group_route - describes a route from a channel of a
>   *	CSI-2 receiver to a VIN
>   *
> + * @master:	VIN group master ID.
>   * @csi:	CSI-2 receiver ID.
> - * @channel:	Output channel of the CSI-2 receiver.
> - * @vin:	VIN ID.
> - * @mask:	Bitmask of the different CHSEL register values that
> - *		allow for a route from @csi + @chan to @vin.
> + * @chsel:	CHSEL register values that connects VIN group to CSI-2.
>   *
>   * .. note::
>   *	Each R-Car CSI-2 receiver has four output channels facing the VIN
> @@ -140,19 +138,11 @@ struct rvin_parallel_entity {
>   *	There is no correlation between channel number and CSI-2 VC. It's
>   *	up to the CSI-2 receiver driver to configure which VC is output
>   *	on which channel, the VIN devices only care about output channels.
> - *
> - *	There are in some cases multiple CHSEL register settings which would
> - *	allow for the same route from @csi + @channel to @vin. For example
> - *	on R-Car H3 both the CHSEL values 0 and 3 allow for a route from
> - *	CSI40/VC0 to VIN0. All possible CHSEL values for a route need to be
> - *	recorded as a bitmask in @mask, in this example bit 0 and 3 should
> - *	be set.
>   */
>  struct rvin_group_route {
> +	unsigned int master;
>  	enum rvin_csi_id csi;
> -	unsigned int channel;
> -	unsigned int vin;
> -	unsigned int mask;
> +	unsigned int chsel;
>  };
>
>  /**
> --
> 2.33.1
>
Niklas Söderlund Nov. 27, 2021, 4:15 p.m. UTC | #2
Hi Jacopo,

Thanks for your feedback.

On 2021-11-04 18:29:33 +0100, Jacopo Mondi wrote:
> Hi Niklas,
> 
> On Wed, Oct 20, 2021 at 10:02:25PM +0200, Niklas Söderlund wrote:
> > When Gen3 support was first added to this R-Car VIN and CSI-2 driver the
> > routing was centred around the CHSEL register which multiplex the
> 
> multiplexes
> 
> > different parallel buses that sits between the CSI-2 receivers source
> 
> buses -> sit
> 
> > side and the VIN dma engines. This was a bad design as the multiplexing
> > do allow for only a few combinations and do not play nice with many
> > video streams in the system.
> >
> > For example it's only possible for CSI-2 Virtual Channels 0 and 1 of any
> > given CSI-2 receiver to be used together with the scaler.
> >
> > Later datasheets have expanded the documentation and it is now possible
> > to improve on this design by allowing any Virtual Channel to be routed
> > to any R-Car VIN instance, provided that there exists a parallel bus
> > between them. This increases the flexibility as all Virtual Channels can
> > now be used together with the scaler for example.
> >
> > The redesign is not however perfect. While the new design allows for
> > many more routes, two constrains limit a small portion of routes that
> > was possible in the old design but are no more.
> >
> > - It is no longer possible to route the same CSI-2 and VC to more then
> >   one VIN at a time. This was theoretically possible before if the
> >   specific SoC allowed for the same CSI-2 and VC to be routed to two
> >   different VIN capture groups.
> 
> I think that's acceptable
> 
> >
> > - It is no longer possible to simultaneously mix links from two CSI-2 IP
> >   blocks to the same VIN capture group.
> 
> This one is a little bit bothering but I don't see it as a huge blocker
> personally.
> 
> >
> >   For example if VIN2 is capturing from CSI40 then VIN{0,1,3} must also
> >   capture from CSI40. While VIN{4,5,6,7} is still free to capture from
> >   any other CSI-2 IP in the system. Once all VIN{0,1,2,3} links to CSI40
> >   are disabled that VIN capture group is free again to capture from any
> >   other CSI-2 IP it is connected to.
> >
> > At the core of the redesign is greater cooperator of the R-Car VIN and
> > CSI-2 drivers in configuring the routing. The VIN driver is after this
> > change only responsible to configure the full VIN capture groups
> > parallel buses to be to a particular CSI-2 IP. While the configuration
> > of which CSI-2 Virtual Channel is outputted on which of the R-Car CSI-2
> > IP output ports is handled by the CSI-2 driver.
> >
> > Before this change the CSI-2 Virtual Channel to output port was static
> > in the CSI-2 driver and the different links only manipulated the VIN
> > capture groups CHSEL register. With this change both the CHSEl register
> > and the CSI-2 routing VCDT registers are modified for greater
> > flexibility.
> >
> > This change touches both the R-Car VIN and R-Car CSI-2 drivers in the
> > same commit as both drivers cooperate closely and one change without the
> > other would more or less break video capture.
> >
> > Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> > ---
> >  drivers/media/platform/rcar-vin/rcar-core.c | 318 +++++---------------
> >  drivers/media/platform/rcar-vin/rcar-csi2.c |  58 +++-
> >  drivers/media/platform/rcar-vin/rcar-dma.c  |   2 +-
> >  drivers/media/platform/rcar-vin/rcar-vin.h  |  18 +-
> >  4 files changed, 136 insertions(+), 260 deletions(-)
> >
> > diff --git a/drivers/media/platform/rcar-vin/rcar-core.c b/drivers/media/platform/rcar-vin/rcar-core.c
> > index 65ab66a072e9d635..6b05ad10e8aa66f9 100644
> > --- a/drivers/media/platform/rcar-vin/rcar-core.c
> > +++ b/drivers/media/platform/rcar-vin/rcar-core.c
> > @@ -745,27 +745,6 @@ static int rvin_parallel_init(struct rvin_dev *vin)
> >   * CSI-2
> >   */
> >
> > -static unsigned int rvin_csi2_get_mask(struct rvin_dev *vin,
> > -				       enum rvin_csi_id csi_id,
> > -				       unsigned char channel)
> > -{
> > -	const struct rvin_group_route *route;
> > -	unsigned int mask = 0;
> > -
> > -	for (route = vin->info->routes; route->mask; route++) {
> > -		if (route->vin == vin->id &&
> > -		    route->csi == csi_id &&
> > -		    route->channel == channel) {
> > -			vin_dbg(vin,
> > -				"Adding route: vin: %d csi: %d channel: %d\n",
> > -				route->vin, route->csi, route->channel);
> > -			mask |= route->mask;
> > -		}
> > -	}
> > -
> > -	return mask;
> > -}
> > -
> >  /*
> >   * Link setup for the links between a VIN and a CSI-2 receiver is a bit
> >   * complex. The reason for this is that the register controlling routing
> > @@ -852,9 +831,9 @@ static int rvin_csi2_link_notify(struct media_link *link, u32 flags,
> >  			link->source->entity->name);
> >  		ret = -ENODEV;
> >  	} else {
> > -		unsigned int master_id, channel, mask_new;
> > -		unsigned int mask = ~0;
> > -		struct media_pad *csi_pad;
> > +		const struct rvin_group_route *route;
> > +		unsigned int chsel = -1;
> > +		unsigned int master_id;
> >
> >  		master_id = rvin_group_id_to_master(vin->id);
> >
> > @@ -863,8 +842,10 @@ static int rvin_csi2_link_notify(struct media_link *link, u32 flags,
> >  			goto out;
> >  		}
> >
> > -		/* Build a mask for already enabled links. */
> > +		/* Make sure group is connected to same CSI-2 */
> >  		for (i = master_id; i < master_id + 4; i++) {
> > +			struct media_pad *csi_pad;
> > +
> >  			if (!group->vin[i])
> >  				continue;
> 
> Are you sure this checks for all VINs in the group to be connected to
> the same CSI-2 receiver ? The loop goes one as
> 
> 		/* Make sure group is connected to same CSI-2 */
> 		for (i = master_id; i < master_id + 4; i++) {
> 			struct media_pad *csi_pad;
> 
> 			if (!group->vin[i])
> 				continue;
> 
> 			/* Get remote CSI-2, if any. */
> 			csi_pad = media_entity_remote_pad(
> 					&group->vin[i]->vdev.entity.pads[0]);
> 			if (!csi_pad)
> 				continue;
> 
> 			if (csi_pad->entity != link->source->entity) {
> 				vin_dbg(vin, "Already attached to %s\n",
> 					csi_pad->entity->name);
> 				ret = -EBUSY;
> 				goto out;
> 			}
> 		}
> 
> Which if I got it right verifies that entity at the other end of the
> link is the same as the link's source entity, which seems to be a
> tautology to me, am I wrong ?

I had to lookup tautology in the dictionary to be able to understand 
your question ;-)

No this is not a pointless checkup as the link is static, as in the link 
that is about to be enabled if everything checks out. While the csi_pad 
is retrieved for each VIN in the group.

Put another way, loop over all VIN in the group and lookup if they have 
an active link. If they do retrieve that links entity and then make sure 
it is the same entity as the link that is about to be enabled. If it's 
not the same we error out.

> 
> Shouldn't you
> 
>         struct media_entity *csi2 = nullptr;
>         for (i = master_id; i < master_id + 4; i++) {
>                 struct media_pad *csi_pad;
> 
>                 if (!group->vin[i])
>                         continue;
> 
>                 csi_pad = media_entity_remote_pad(
>                                 &group->vin[i]->vdev.entity.pads[0]);
> 
>                 if (!csi2) {
>                         csi2 = csi_pad->entity;
>                         continue;
>                 }
> 
>                 if (csi2 != csi2_pad->entity)
>                         return -EINVAL;
> 
>         }
> 
> >
> > @@ -874,26 +855,24 @@ static int rvin_csi2_link_notify(struct media_link *link, u32 flags,
> >  			if (!csi_pad)
> >  				continue;
> >
> > -			csi_id = rvin_group_entity_to_remote_id(group,
> > -								csi_pad->entity);
> > -			channel = rvin_group_csi_pad_to_channel(csi_pad->index);
> > -
> > -			mask &= rvin_csi2_get_mask(group->vin[i], csi_id, channel);
> > +			if (csi_pad->entity != link->source->entity) {
> > +				vin_dbg(vin, "Already attached to %s\n",
> > +					csi_pad->entity->name);
> > +				ret = -EBUSY;
> > +				goto out;
> > +			}
> >  		}
> >
> > -		channel = rvin_group_csi_pad_to_channel(link->source->index);
> > -		mask_new = mask & rvin_csi2_get_mask(vin, csi_id, channel);
> > -		vin_dbg(vin, "Try link change mask: 0x%x new: 0x%x\n", mask,
> > -			mask_new);
> > -
> > -		if (!mask_new) {
> > -			ret = -EMLINK;
> > -			goto out;
> > +		for (route = vin->info->routes; route->chsel; route++) {
> > +			if (route->master == master_id && route->csi == csi_id) {
> > +				chsel = route->chsel;
> > +				break;
> > +			}
> >  		}
> >
> > -		/* New valid CHSEL found, set the new value. */
> > -		ret = rvin_set_channel_routing(group->vin[master_id],
> > -					       __ffs(mask_new));
> > +		BUG_ON(chsel < 0);
> > +
> > +		ret = rvin_set_channel_routing(group->vin[master_id], chsel);
> >  		if (ret)
> >  			goto out;
> >
> > @@ -909,46 +888,59 @@ static const struct media_device_ops rvin_csi2_media_ops = {
> >  	.link_notify = rvin_csi2_link_notify,
> >  };
> >
> > -static int rvin_csi2_add_route(struct rvin_group *group,
> > -			       const struct rvin_group_route *route)
> > +static int rvin_csi2_add_routes(struct rvin_group *group, unsigned int id,
> > +				const struct rvin_group_route *route)
> >
> >  {
> >  	struct media_entity *source = &group->remotes[route->csi].subdev->entity;
> > -	unsigned int source_idx = rvin_group_csi_channel_to_pad(route->channel);
> > -	struct media_entity *sink = &group->vin[route->vin]->vdev.entity;
> > -	struct media_pad *source_pad = &source->pads[source_idx];
> > +	struct media_entity *sink = &group->vin[id]->vdev.entity;
> >  	struct media_pad *sink_pad = &sink->pads[0];
> > +	unsigned int channel;
> > +	int ret;
> >
> > -	if (media_entity_find_link(source_pad, sink_pad))
> > -		return 0;
> > +	for (channel = 0; channel < 4; channel++) {
> > +		unsigned int source_idx = rvin_group_csi_channel_to_pad(channel);
> > +		struct media_pad *source_pad = &source->pads[source_idx];
> >
> > -	return media_create_pad_link(source, source_idx, sink, 0, 0);
> > +		if (media_entity_find_link(source_pad, sink_pad))
> > +			continue;
> > +
> > +		ret = media_create_pad_link(source, source_idx, sink, 0, 0);
> > +		if (ret)
> > +			return ret;
> > +	}
> > +
> > +	return 0;
> >  }
> >
> >  static int rvin_csi2_setup_links(struct rvin_dev *vin)
> >  {
> >  	const struct rvin_group_route *route;
> > +	unsigned int id;
> >  	int ret = -EINVAL;
> >
> >  	/* Create all media device links between VINs and CSI-2's. */
> >  	mutex_lock(&vin->group->lock);
> > -	for (route = vin->info->routes; route->mask; route++) {
> > -		/* Check that VIN is part of the group. */
> > -		if (!vin->group->vin[route->vin])
> > -			continue;
> > -
> > +	for (route = vin->info->routes; route->chsel; route++) {
> >  		/* Check that VIN' master is part of the group. */
> > -		if (!vin->group->vin[rvin_group_id_to_master(route->vin)])
> > +		if (!vin->group->vin[route->master])
> >  			continue;
> >
> >  		/* Check that CSI-2 is part of the group. */
> >  		if (!vin->group->remotes[route->csi].subdev)
> >  			continue;
> >
> > -		ret = rvin_csi2_add_route(vin->group, route);
> > -		if (ret)
> > -			break;
> > +		for (id = route->master; id < route->master + 4; id++) {
> > +			/* Check that VIN is part of the group. */
> > +			if (!vin->group->vin[id])
> > +				continue;
> > +
> > +			ret = rvin_csi2_add_routes(vin->group, id, route);
> > +			if (ret)
> > +				goto out;
> > +		}
> >  	}
> > +out:
> >  	mutex_unlock(&vin->group->lock);
> >
> >  	return ret;
> > @@ -1158,30 +1150,9 @@ static const struct rvin_info rcar_info_gen2 = {
> >  };
> >
> >  static const struct rvin_group_route rcar_info_r8a774e1_routes[] = {
> > -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 0, .mask = BIT(0) | BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 0, .mask = BIT(1) | BIT(4) },
> > -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 0, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 1, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 1, .mask = BIT(1) | BIT(3) },
> > -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 1, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 1, .mask = BIT(4) },
> > -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 2, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 2, .mask = BIT(1) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 2, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI40, .channel = 2, .vin = 2, .mask = BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 2, .vin = 2, .mask = BIT(4) },
> > -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 3, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 3, .mask = BIT(1) | BIT(2) },
> > -	{ .csi = RVIN_CSI40, .channel = 3, .vin = 3, .mask = BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 3, .vin = 3, .mask = BIT(4) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 4, .mask = BIT(1) | BIT(4) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 5, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 5, .mask = BIT(4) },
> > -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 6, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 6, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI20, .channel = 2, .vin = 6, .mask = BIT(4) },
> > -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 7, .mask = BIT(1) | BIT(2) },
> > -	{ .csi = RVIN_CSI20, .channel = 3, .vin = 7, .mask = BIT(4) },
> > +	{ .master = 0, .csi = RVIN_CSI20, .chsel = 0x04 },
> > +	{ .master = 0, .csi = RVIN_CSI40, .chsel = 0x03 },
> > +	{ .master = 4, .csi = RVIN_CSI20, .chsel = 0x04 },
> >  	{ /* Sentinel */ }
> >  };
> >
> > @@ -1194,38 +1165,10 @@ static const struct rvin_info rcar_info_r8a774e1 = {
> >  };
> >
> >  static const struct rvin_group_route rcar_info_r8a7795_routes[] = {
> > -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 0, .mask = BIT(0) | BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 0, .mask = BIT(1) | BIT(4) },
> > -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 0, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 1, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 1, .mask = BIT(1) | BIT(3) },
> > -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 1, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 1, .mask = BIT(4) },
> > -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 2, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 2, .mask = BIT(1) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 2, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI40, .channel = 2, .vin = 2, .mask = BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 2, .vin = 2, .mask = BIT(4) },
> > -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 3, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 3, .mask = BIT(1) | BIT(2) },
> > -	{ .csi = RVIN_CSI40, .channel = 3, .vin = 3, .mask = BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 3, .vin = 3, .mask = BIT(4) },
> > -	{ .csi = RVIN_CSI41, .channel = 0, .vin = 4, .mask = BIT(0) | BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 4, .mask = BIT(1) | BIT(4) },
> > -	{ .csi = RVIN_CSI41, .channel = 1, .vin = 4, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 5, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI41, .channel = 1, .vin = 5, .mask = BIT(1) | BIT(3) },
> > -	{ .csi = RVIN_CSI41, .channel = 0, .vin = 5, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 5, .mask = BIT(4) },
> > -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 6, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI41, .channel = 0, .vin = 6, .mask = BIT(1) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 6, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI41, .channel = 2, .vin = 6, .mask = BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 2, .vin = 6, .mask = BIT(4) },
> > -	{ .csi = RVIN_CSI41, .channel = 1, .vin = 7, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 7, .mask = BIT(1) | BIT(2) },
> > -	{ .csi = RVIN_CSI41, .channel = 3, .vin = 7, .mask = BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 3, .vin = 7, .mask = BIT(4) },
> > +	{ .master = 0, .csi = RVIN_CSI20, .chsel = 0x04 },
> > +	{ .master = 0, .csi = RVIN_CSI40, .chsel = 0x03 },
> > +	{ .master = 4, .csi = RVIN_CSI20, .chsel = 0x04 },
> > +	{ .master = 4, .csi = RVIN_CSI41, .chsel = 0x03 },
> >  	{ /* Sentinel */ }
> >  };
> >
> > @@ -1239,48 +1182,12 @@ static const struct rvin_info rcar_info_r8a7795 = {
> >  };
> >
> >  static const struct rvin_group_route rcar_info_r8a7795es1_routes[] = {
> > -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 0, .mask = BIT(0) | BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 0, .mask = BIT(1) | BIT(4) },
> > -	{ .csi = RVIN_CSI21, .channel = 0, .vin = 0, .mask = BIT(2) | BIT(5) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 1, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI21, .channel = 0, .vin = 1, .mask = BIT(1) },
> > -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 1, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 1, .mask = BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 1, .mask = BIT(4) },
> > -	{ .csi = RVIN_CSI21, .channel = 1, .vin = 1, .mask = BIT(5) },
> > -	{ .csi = RVIN_CSI21, .channel = 0, .vin = 2, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 2, .mask = BIT(1) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 2, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI40, .channel = 2, .vin = 2, .mask = BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 2, .vin = 2, .mask = BIT(4) },
> > -	{ .csi = RVIN_CSI21, .channel = 2, .vin = 2, .mask = BIT(5) },
> > -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 3, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 3, .mask = BIT(1) },
> > -	{ .csi = RVIN_CSI21, .channel = 1, .vin = 3, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI40, .channel = 3, .vin = 3, .mask = BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 3, .vin = 3, .mask = BIT(4) },
> > -	{ .csi = RVIN_CSI21, .channel = 3, .vin = 3, .mask = BIT(5) },
> > -	{ .csi = RVIN_CSI41, .channel = 0, .vin = 4, .mask = BIT(0) | BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 4, .mask = BIT(1) | BIT(4) },
> > -	{ .csi = RVIN_CSI21, .channel = 0, .vin = 4, .mask = BIT(2) | BIT(5) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 5, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI21, .channel = 0, .vin = 5, .mask = BIT(1) },
> > -	{ .csi = RVIN_CSI41, .channel = 0, .vin = 5, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI41, .channel = 1, .vin = 5, .mask = BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 5, .mask = BIT(4) },
> > -	{ .csi = RVIN_CSI21, .channel = 1, .vin = 5, .mask = BIT(5) },
> > -	{ .csi = RVIN_CSI21, .channel = 0, .vin = 6, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI41, .channel = 0, .vin = 6, .mask = BIT(1) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 6, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI41, .channel = 2, .vin = 6, .mask = BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 2, .vin = 6, .mask = BIT(4) },
> > -	{ .csi = RVIN_CSI21, .channel = 2, .vin = 6, .mask = BIT(5) },
> > -	{ .csi = RVIN_CSI41, .channel = 1, .vin = 7, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 7, .mask = BIT(1) },
> > -	{ .csi = RVIN_CSI21, .channel = 1, .vin = 7, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI41, .channel = 3, .vin = 7, .mask = BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 3, .vin = 7, .mask = BIT(4) },
> > -	{ .csi = RVIN_CSI21, .channel = 3, .vin = 7, .mask = BIT(5) },
> > +	{ .master = 0, .csi = RVIN_CSI20, .chsel = 0x04 },
> > +	{ .master = 0, .csi = RVIN_CSI20, .chsel = 0x05 },
> > +	{ .master = 0, .csi = RVIN_CSI40, .chsel = 0x03 },
> > +	{ .master = 4, .csi = RVIN_CSI20, .chsel = 0x04 },
> > +	{ .master = 4, .csi = RVIN_CSI20, .chsel = 0x05 },
> > +	{ .master = 4, .csi = RVIN_CSI40, .chsel = 0x03 },
> 
> This is really bothering, as otherwise in all other routes
> 
>         .csi == RVIN_CSI4x -> chsel = 0x03
>         .csi == RVIN_CSI2x -> chsel = 0x04

It is also a very good review spot as the table is wrong, it also do not 
consider CSI21 at all after the change, the correct table is,

    static const struct rvin_group_route rcar_info_r8a7795es1_routes[] = 
    {
            { .master = 0, .csi = RVIN_CSI20, .chsel = 0x04 },
            { .master = 0, .csi = RVIN_CSI21, .chsel = 0x05 },
            { .master = 0, .csi = RVIN_CSI40, .chsel = 0x03 },
            { .master = 4, .csi = RVIN_CSI20, .chsel = 0x04 },
            { .master = 4, .csi = RVIN_CSI21, .chsel = 0x05 },
            { .master = 4, .csi = RVIN_CSI41, .chsel = 0x03 },
            { /* Sentinel */ }
    };

Thanks for spotting this!

> 
> >  	{ /* Sentinel */ }
> >  };
> >
> > @@ -1293,34 +1200,10 @@ static const struct rvin_info rcar_info_r8a7795es1 = {
> >  };
> >
> >  static const struct rvin_group_route rcar_info_r8a7796_routes[] = {
> > -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 0, .mask = BIT(0) | BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 0, .mask = BIT(1) | BIT(4) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 1, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 1, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 1, .mask = BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 1, .mask = BIT(4) },
> > -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 2, .mask = BIT(1) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 2, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI40, .channel = 2, .vin = 2, .mask = BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 2, .vin = 2, .mask = BIT(4) },
> > -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 3, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 3, .mask = BIT(1) },
> > -	{ .csi = RVIN_CSI40, .channel = 3, .vin = 3, .mask = BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 3, .vin = 3, .mask = BIT(4) },
> > -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 4, .mask = BIT(0) | BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 4, .mask = BIT(1) | BIT(4) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 5, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 5, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 5, .mask = BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 5, .mask = BIT(4) },
> > -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 6, .mask = BIT(1) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 6, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI40, .channel = 2, .vin = 6, .mask = BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 2, .vin = 6, .mask = BIT(4) },
> > -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 7, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 7, .mask = BIT(1) },
> > -	{ .csi = RVIN_CSI40, .channel = 3, .vin = 7, .mask = BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 3, .vin = 7, .mask = BIT(4) },
> > +	{ .master = 0, .csi = RVIN_CSI20, .chsel = 0x04 },
> > +	{ .master = 0, .csi = RVIN_CSI40, .chsel = 0x03 },
> > +	{ .master = 4, .csi = RVIN_CSI20, .chsel = 0x04 },
> > +	{ .master = 4, .csi = RVIN_CSI40, .chsel = 0x03 },
> >  	{ /* Sentinel */ }
> >  };
> >
> > @@ -1334,38 +1217,10 @@ static const struct rvin_info rcar_info_r8a7796 = {
> >  };
> >
> >  static const struct rvin_group_route rcar_info_r8a77965_routes[] = {
> > -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 0, .mask = BIT(0) | BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 0, .mask = BIT(1) | BIT(4) },
> > -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 0, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 1, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 1, .mask = BIT(1) | BIT(3) },
> > -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 1, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 1, .mask = BIT(4) },
> > -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 2, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 2, .mask = BIT(1) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 2, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI40, .channel = 2, .vin = 2, .mask = BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 2, .vin = 2, .mask = BIT(4) },
> > -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 3, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 3, .mask = BIT(1) | BIT(2) },
> > -	{ .csi = RVIN_CSI40, .channel = 3, .vin = 3, .mask = BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 3, .vin = 3, .mask = BIT(4) },
> > -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 4, .mask = BIT(0) | BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 4, .mask = BIT(1) | BIT(4) },
> > -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 4, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 5, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 5, .mask = BIT(1) | BIT(3) },
> > -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 5, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 5, .mask = BIT(4) },
> > -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 6, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 6, .mask = BIT(1) },
> > -	{ .csi = RVIN_CSI20, .channel = 0, .vin = 6, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI40, .channel = 2, .vin = 6, .mask = BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 2, .vin = 6, .mask = BIT(4) },
> > -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 7, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI20, .channel = 1, .vin = 7, .mask = BIT(1) | BIT(2) },
> > -	{ .csi = RVIN_CSI40, .channel = 3, .vin = 7, .mask = BIT(3) },
> > -	{ .csi = RVIN_CSI20, .channel = 3, .vin = 7, .mask = BIT(4) },
> > +	{ .master = 0, .csi = RVIN_CSI20, .chsel = 0x04 },
> > +	{ .master = 0, .csi = RVIN_CSI40, .chsel = 0x03 },
> > +	{ .master = 4, .csi = RVIN_CSI20, .chsel = 0x04 },
> > +	{ .master = 4, .csi = RVIN_CSI40, .chsel = 0x03 },
> >  	{ /* Sentinel */ }
> >  };
> >
> > @@ -1379,13 +1234,7 @@ static const struct rvin_info rcar_info_r8a77965 = {
> >  };
> >
> >  static const struct rvin_group_route rcar_info_r8a77970_routes[] = {
> > -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 0, .mask = BIT(0) | BIT(3) },
> > -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 1, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 1, .mask = BIT(3) },
> > -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 2, .mask = BIT(1) },
> > -	{ .csi = RVIN_CSI40, .channel = 2, .vin = 2, .mask = BIT(3) },
> > -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 3, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI40, .channel = 3, .vin = 3, .mask = BIT(3) },
> > +	{ .master = 0, .csi = RVIN_CSI40, .chsel = 0x03 },
> >  	{ /* Sentinel */ }
> >  };
> >
> > @@ -1398,22 +1247,8 @@ static const struct rvin_info rcar_info_r8a77970 = {
> >  };
> >
> >  static const struct rvin_group_route rcar_info_r8a77980_routes[] = {
> > -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 0, .mask = BIT(0) | BIT(3) },
> > -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 0, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 1, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 1, .mask = BIT(1) | BIT(3) },
> > -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 2, .mask = BIT(1) },
> > -	{ .csi = RVIN_CSI40, .channel = 2, .vin = 2, .mask = BIT(3) },
> > -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 3, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI40, .channel = 3, .vin = 3, .mask = BIT(3) },
> > -	{ .csi = RVIN_CSI41, .channel = 0, .vin = 4, .mask = BIT(0) | BIT(3) },
> > -	{ .csi = RVIN_CSI41, .channel = 1, .vin = 4, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI41, .channel = 0, .vin = 5, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI41, .channel = 1, .vin = 5, .mask = BIT(1) | BIT(3) },
> > -	{ .csi = RVIN_CSI41, .channel = 0, .vin = 6, .mask = BIT(1) },
> > -	{ .csi = RVIN_CSI41, .channel = 2, .vin = 6, .mask = BIT(3) },
> > -	{ .csi = RVIN_CSI41, .channel = 1, .vin = 7, .mask = BIT(0) },
> > -	{ .csi = RVIN_CSI41, .channel = 3, .vin = 7, .mask = BIT(3) },
> > +	{ .master = 0, .csi = RVIN_CSI40, .chsel = 0x03 },
> > +	{ .master = 4, .csi = RVIN_CSI41, .chsel = 0x03 },
> >  	{ /* Sentinel */ }
> >  };
> >
> > @@ -1427,10 +1262,7 @@ static const struct rvin_info rcar_info_r8a77980 = {
> >  };
> >
> >  static const struct rvin_group_route rcar_info_r8a77990_routes[] = {
> > -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 4, .mask = BIT(0) | BIT(3) },
> > -	{ .csi = RVIN_CSI40, .channel = 0, .vin = 5, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 4, .mask = BIT(2) },
> > -	{ .csi = RVIN_CSI40, .channel = 1, .vin = 5, .mask = BIT(1) | BIT(3) },
> > +	{ .master = 0, .csi = RVIN_CSI40, .chsel = 0x03 },
> >  	{ /* Sentinel */ }
> >  };
> >
> > diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c b/drivers/media/platform/rcar-vin/rcar-csi2.c
> > index 11848d0c4a55cb4c..b8c56d248454efbf 100644
> > --- a/drivers/media/platform/rcar-vin/rcar-csi2.c
> > +++ b/drivers/media/platform/rcar-vin/rcar-csi2.c
> > @@ -468,6 +468,8 @@ struct rcar_csi2 {
> >  	struct v4l2_subdev *remote;
> >  	unsigned int remote_pad;
> >
> > +	int channel_vc[4];
> > +
> >  	struct mutex lock; /* Protects mf and stream_count. */
> >  	struct v4l2_mbus_framefmt mf;
> >  	int stream_count;
> > @@ -664,8 +666,11 @@ static int rcsi2_start_receiver(struct rcar_csi2 *priv)
> >  	for (i = 0; i < priv->info->num_channels; i++) {
> >  		u32 vcdt_part;
> >
> > -		vcdt_part = VCDT_SEL_VC(i) | VCDT_VCDTN_EN | VCDT_SEL_DTN_ON |
> > -			VCDT_SEL_DT(format->datatype);
> > +		if (priv->channel_vc[i] < 0)
> > +			continue;
> > +
> > +		vcdt_part = VCDT_SEL_VC(priv->channel_vc[i]) | VCDT_VCDTN_EN |
> > +			VCDT_SEL_DTN_ON | VCDT_SEL_DT(format->datatype);
> >
> >  		/* Store in correct reg and offset. */
> >  		if (i < 2)
> > @@ -1240,7 +1245,53 @@ static int rcsi2_init_phtw_v3u(struct rcar_csi2 *priv,
> >   * Platform Device Driver.
> >   */
> >
> > +static int rcsi2_link_setup(struct media_entity *entity,
> > +			    const struct media_pad *local,
> > +			    const struct media_pad *remote, u32 flags)
> > +{
> > +	struct v4l2_subdev *sd = media_entity_to_v4l2_subdev(entity);
> > +	struct rcar_csi2 *priv = sd_to_csi2(sd);
> > +	struct video_device *vdev;
> > +	int channel, vc;
> > +	u32 id;
> > +
> > +	if (!is_media_entity_v4l2_video_device(remote->entity)) {
> 
> Can this happen ?

It *should* not happen, but better safe then sorry :-)

> 
> > +		dev_err(priv->dev, "Remote is not a video device\n");
> > +		return -EINVAL;
> > +	}
> > +
> > +	vdev = media_entity_to_video_device(remote->entity);
> > +
> > +	if (of_property_read_u32(vdev->dev_parent->of_node, "renesas,id", &id)) {
> 
> Reading properties from a remote device node usually makes people
> scream but I understand the purpose here and it doesn't sound -that-
> bad
> 
> > +		dev_err(priv->dev, "No renesas,id, can't configure routing\n");
> > +		return -EINVAL;
> > +	}
> 
> Ouch, I take back my initial assumption that is harmless to not being
> able anymore to capture the same VC from multiple VIN, in particular
> in regards to embedded data.

The limitation of not being able to capture the same VC on multiple is 
set by the hardware and not by the driver itself. It's just that before 
this change the link setup allowed for this situation while after this 
change it is not.

> 
> CHSEL[3] allows to select if a specific VC or "CSI-2 embedded data
> of Virtual Channel 0" has to be captured. This setup prevents to
> output on two channels VC0 and filter out embedded data if I'm not
> mistaken...

Well, we don't support capturing embedded data before this change so I'm 
not worried about that. However this takes the drivers a step closer to 
enabling it.

From the R-Car CSI-2 point of view (it's the component limiting that we 
can only route one VC to one VIN) the embedded data is a separate 
channel so we do not limit anything here, we just need to extend the 
driver CSI-2 and VIN driver to support embedded data. But for that we 
need a setup that generates embedded data to test on.

> 
> > +
> > +	channel = id % 4;
> > +
> > +	if (flags & MEDIA_LNK_FL_ENABLED) {
> > +		if (media_entity_remote_pad(local)) {
> > +			dev_dbg(priv->dev,
> > +				"Each VC can only be routed to one output channel\n");
> 
> Can this limitation be lifted to support capturing embedded data from
> VC0 ? That would require mixing media links and formats though :(

The idea is to add a new pad on the R-Car CSI-2 subdevice to output the 
embedded data. That way we will pretend it's just another virtual 
channel and the logic will be the same as for a channel carrying pixel 
data.

> 
> > +			return -EINVAL;
> > +		}
> > +
> > +		vc = local->index - 1;
> > +
> > +		dev_dbg(priv->dev, "Route VC%d to VIN%u on output channel %d\n",
> > +			vc, id, channel);
> > +	} else {
> > +		vc = -1;
> > +	}
> > +
> > +	priv->channel_vc[channel] = vc;
> > +
> > +	return 0;
> > +}
> > +
> > +
> >  static const struct media_entity_operations rcar_csi2_entity_ops = {
> > +	.link_setup = rcsi2_link_setup,
> >  	.link_validate = v4l2_subdev_link_validate,
> >  };
> >
> > @@ -1459,6 +1510,9 @@ static int rcsi2_probe(struct platform_device *pdev)
> >  	if (ret)
> >  		goto error_async;
> >
> > +	for (i = 0; i < ARRAY_SIZE(priv->channel_vc); i++)
> > +		priv->channel_vc[i] = -1;
> > +
> >  	pm_runtime_enable(&pdev->dev);
> >
> >  	ret = v4l2_async_register_subdev(&priv->subdev);
> > diff --git a/drivers/media/platform/rcar-vin/rcar-dma.c b/drivers/media/platform/rcar-vin/rcar-dma.c
> > index 25ead9333d0046e7..b72ae27a407dc96c 100644
> > --- a/drivers/media/platform/rcar-vin/rcar-dma.c
> > +++ b/drivers/media/platform/rcar-vin/rcar-dma.c
> > @@ -1490,7 +1490,7 @@ int rvin_set_channel_routing(struct rvin_dev *vin, u8 chsel)
> >  	 * register. IFMD_DES1 controls data expansion mode for CSI20/21,
> >  	 * IFMD_DES0 controls data expansion mode for CSI40/41.
> >  	 */
> > -	for (route = vin->info->routes; route->mask; route++) {
> > +	for (route = vin->info->routes; route->chsel; route++) {
> >  		if (route->csi == RVIN_CSI20 || route->csi == RVIN_CSI21)
> >  			ifmd |= VNCSI_IFMD_DES1;
> >  		else
> > diff --git a/drivers/media/platform/rcar-vin/rcar-vin.h b/drivers/media/platform/rcar-vin/rcar-vin.h
> > index 6c06320174a2ed96..ddc1830be9a5d6c3 100644
> > --- a/drivers/media/platform/rcar-vin/rcar-vin.h
> > +++ b/drivers/media/platform/rcar-vin/rcar-vin.h
> > @@ -128,11 +128,9 @@ struct rvin_parallel_entity {
> >   * struct rvin_group_route - describes a route from a channel of a
> >   *	CSI-2 receiver to a VIN
> >   *
> > + * @master:	VIN group master ID.
> >   * @csi:	CSI-2 receiver ID.
> > - * @channel:	Output channel of the CSI-2 receiver.
> > - * @vin:	VIN ID.
> > - * @mask:	Bitmask of the different CHSEL register values that
> > - *		allow for a route from @csi + @chan to @vin.
> > + * @chsel:	CHSEL register values that connects VIN group to CSI-2.
> >   *
> >   * .. note::
> >   *	Each R-Car CSI-2 receiver has four output channels facing the VIN
> > @@ -140,19 +138,11 @@ struct rvin_parallel_entity {
> >   *	There is no correlation between channel number and CSI-2 VC. It's
> >   *	up to the CSI-2 receiver driver to configure which VC is output
> >   *	on which channel, the VIN devices only care about output channels.
> > - *
> > - *	There are in some cases multiple CHSEL register settings which would
> > - *	allow for the same route from @csi + @channel to @vin. For example
> > - *	on R-Car H3 both the CHSEL values 0 and 3 allow for a route from
> > - *	CSI40/VC0 to VIN0. All possible CHSEL values for a route need to be
> > - *	recorded as a bitmask in @mask, in this example bit 0 and 3 should
> > - *	be set.
> >   */
> >  struct rvin_group_route {
> > +	unsigned int master;
> >  	enum rvin_csi_id csi;
> > -	unsigned int channel;
> > -	unsigned int vin;
> > -	unsigned int mask;
> > +	unsigned int chsel;
> >  };
> >
> >  /**
> > --
> > 2.33.1
> >
diff mbox series

Patch

diff --git a/drivers/media/platform/rcar-vin/rcar-core.c b/drivers/media/platform/rcar-vin/rcar-core.c
index 65ab66a072e9d635..6b05ad10e8aa66f9 100644
--- a/drivers/media/platform/rcar-vin/rcar-core.c
+++ b/drivers/media/platform/rcar-vin/rcar-core.c
@@ -745,27 +745,6 @@  static int rvin_parallel_init(struct rvin_dev *vin)
  * CSI-2
  */
 
-static unsigned int rvin_csi2_get_mask(struct rvin_dev *vin,
-				       enum rvin_csi_id csi_id,
-				       unsigned char channel)
-{
-	const struct rvin_group_route *route;
-	unsigned int mask = 0;
-
-	for (route = vin->info->routes; route->mask; route++) {
-		if (route->vin == vin->id &&
-		    route->csi == csi_id &&
-		    route->channel == channel) {
-			vin_dbg(vin,
-				"Adding route: vin: %d csi: %d channel: %d\n",
-				route->vin, route->csi, route->channel);
-			mask |= route->mask;
-		}
-	}
-
-	return mask;
-}
-
 /*
  * Link setup for the links between a VIN and a CSI-2 receiver is a bit
  * complex. The reason for this is that the register controlling routing
@@ -852,9 +831,9 @@  static int rvin_csi2_link_notify(struct media_link *link, u32 flags,
 			link->source->entity->name);
 		ret = -ENODEV;
 	} else {
-		unsigned int master_id, channel, mask_new;
-		unsigned int mask = ~0;
-		struct media_pad *csi_pad;
+		const struct rvin_group_route *route;
+		unsigned int chsel = -1;
+		unsigned int master_id;
 
 		master_id = rvin_group_id_to_master(vin->id);
 
@@ -863,8 +842,10 @@  static int rvin_csi2_link_notify(struct media_link *link, u32 flags,
 			goto out;
 		}
 
-		/* Build a mask for already enabled links. */
+		/* Make sure group is connected to same CSI-2 */
 		for (i = master_id; i < master_id + 4; i++) {
+			struct media_pad *csi_pad;
+
 			if (!group->vin[i])
 				continue;
 
@@ -874,26 +855,24 @@  static int rvin_csi2_link_notify(struct media_link *link, u32 flags,
 			if (!csi_pad)
 				continue;
 
-			csi_id = rvin_group_entity_to_remote_id(group,
-								csi_pad->entity);
-			channel = rvin_group_csi_pad_to_channel(csi_pad->index);
-
-			mask &= rvin_csi2_get_mask(group->vin[i], csi_id, channel);
+			if (csi_pad->entity != link->source->entity) {
+				vin_dbg(vin, "Already attached to %s\n",
+					csi_pad->entity->name);
+				ret = -EBUSY;
+				goto out;
+			}
 		}
 
-		channel = rvin_group_csi_pad_to_channel(link->source->index);
-		mask_new = mask & rvin_csi2_get_mask(vin, csi_id, channel);
-		vin_dbg(vin, "Try link change mask: 0x%x new: 0x%x\n", mask,
-			mask_new);
-
-		if (!mask_new) {
-			ret = -EMLINK;
-			goto out;
+		for (route = vin->info->routes; route->chsel; route++) {
+			if (route->master == master_id && route->csi == csi_id) {
+				chsel = route->chsel;
+				break;
+			}
 		}
 
-		/* New valid CHSEL found, set the new value. */
-		ret = rvin_set_channel_routing(group->vin[master_id],
-					       __ffs(mask_new));
+		BUG_ON(chsel < 0);
+
+		ret = rvin_set_channel_routing(group->vin[master_id], chsel);
 		if (ret)
 			goto out;
 
@@ -909,46 +888,59 @@  static const struct media_device_ops rvin_csi2_media_ops = {
 	.link_notify = rvin_csi2_link_notify,
 };
 
-static int rvin_csi2_add_route(struct rvin_group *group,
-			       const struct rvin_group_route *route)
+static int rvin_csi2_add_routes(struct rvin_group *group, unsigned int id,
+				const struct rvin_group_route *route)
 
 {
 	struct media_entity *source = &group->remotes[route->csi].subdev->entity;
-	unsigned int source_idx = rvin_group_csi_channel_to_pad(route->channel);
-	struct media_entity *sink = &group->vin[route->vin]->vdev.entity;
-	struct media_pad *source_pad = &source->pads[source_idx];
+	struct media_entity *sink = &group->vin[id]->vdev.entity;
 	struct media_pad *sink_pad = &sink->pads[0];
+	unsigned int channel;
+	int ret;
 
-	if (media_entity_find_link(source_pad, sink_pad))
-		return 0;
+	for (channel = 0; channel < 4; channel++) {
+		unsigned int source_idx = rvin_group_csi_channel_to_pad(channel);
+		struct media_pad *source_pad = &source->pads[source_idx];
 
-	return media_create_pad_link(source, source_idx, sink, 0, 0);
+		if (media_entity_find_link(source_pad, sink_pad))
+			continue;
+
+		ret = media_create_pad_link(source, source_idx, sink, 0, 0);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
 }
 
 static int rvin_csi2_setup_links(struct rvin_dev *vin)
 {
 	const struct rvin_group_route *route;
+	unsigned int id;
 	int ret = -EINVAL;
 
 	/* Create all media device links between VINs and CSI-2's. */
 	mutex_lock(&vin->group->lock);
-	for (route = vin->info->routes; route->mask; route++) {
-		/* Check that VIN is part of the group. */
-		if (!vin->group->vin[route->vin])
-			continue;
-
+	for (route = vin->info->routes; route->chsel; route++) {
 		/* Check that VIN' master is part of the group. */
-		if (!vin->group->vin[rvin_group_id_to_master(route->vin)])
+		if (!vin->group->vin[route->master])
 			continue;
 
 		/* Check that CSI-2 is part of the group. */
 		if (!vin->group->remotes[route->csi].subdev)
 			continue;
 
-		ret = rvin_csi2_add_route(vin->group, route);
-		if (ret)
-			break;
+		for (id = route->master; id < route->master + 4; id++) {
+			/* Check that VIN is part of the group. */
+			if (!vin->group->vin[id])
+				continue;
+
+			ret = rvin_csi2_add_routes(vin->group, id, route);
+			if (ret)
+				goto out;
+		}
 	}
+out:
 	mutex_unlock(&vin->group->lock);
 
 	return ret;
@@ -1158,30 +1150,9 @@  static const struct rvin_info rcar_info_gen2 = {
 };
 
 static const struct rvin_group_route rcar_info_r8a774e1_routes[] = {
-	{ .csi = RVIN_CSI40, .channel = 0, .vin = 0, .mask = BIT(0) | BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 0, .mask = BIT(1) | BIT(4) },
-	{ .csi = RVIN_CSI40, .channel = 1, .vin = 0, .mask = BIT(2) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 1, .mask = BIT(0) },
-	{ .csi = RVIN_CSI40, .channel = 1, .vin = 1, .mask = BIT(1) | BIT(3) },
-	{ .csi = RVIN_CSI40, .channel = 0, .vin = 1, .mask = BIT(2) },
-	{ .csi = RVIN_CSI20, .channel = 1, .vin = 1, .mask = BIT(4) },
-	{ .csi = RVIN_CSI20, .channel = 1, .vin = 2, .mask = BIT(0) },
-	{ .csi = RVIN_CSI40, .channel = 0, .vin = 2, .mask = BIT(1) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 2, .mask = BIT(2) },
-	{ .csi = RVIN_CSI40, .channel = 2, .vin = 2, .mask = BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 2, .vin = 2, .mask = BIT(4) },
-	{ .csi = RVIN_CSI40, .channel = 1, .vin = 3, .mask = BIT(0) },
-	{ .csi = RVIN_CSI20, .channel = 1, .vin = 3, .mask = BIT(1) | BIT(2) },
-	{ .csi = RVIN_CSI40, .channel = 3, .vin = 3, .mask = BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 3, .vin = 3, .mask = BIT(4) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 4, .mask = BIT(1) | BIT(4) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 5, .mask = BIT(0) },
-	{ .csi = RVIN_CSI20, .channel = 1, .vin = 5, .mask = BIT(4) },
-	{ .csi = RVIN_CSI20, .channel = 1, .vin = 6, .mask = BIT(0) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 6, .mask = BIT(2) },
-	{ .csi = RVIN_CSI20, .channel = 2, .vin = 6, .mask = BIT(4) },
-	{ .csi = RVIN_CSI20, .channel = 1, .vin = 7, .mask = BIT(1) | BIT(2) },
-	{ .csi = RVIN_CSI20, .channel = 3, .vin = 7, .mask = BIT(4) },
+	{ .master = 0, .csi = RVIN_CSI20, .chsel = 0x04 },
+	{ .master = 0, .csi = RVIN_CSI40, .chsel = 0x03 },
+	{ .master = 4, .csi = RVIN_CSI20, .chsel = 0x04 },
 	{ /* Sentinel */ }
 };
 
@@ -1194,38 +1165,10 @@  static const struct rvin_info rcar_info_r8a774e1 = {
 };
 
 static const struct rvin_group_route rcar_info_r8a7795_routes[] = {
-	{ .csi = RVIN_CSI40, .channel = 0, .vin = 0, .mask = BIT(0) | BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 0, .mask = BIT(1) | BIT(4) },
-	{ .csi = RVIN_CSI40, .channel = 1, .vin = 0, .mask = BIT(2) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 1, .mask = BIT(0) },
-	{ .csi = RVIN_CSI40, .channel = 1, .vin = 1, .mask = BIT(1) | BIT(3) },
-	{ .csi = RVIN_CSI40, .channel = 0, .vin = 1, .mask = BIT(2) },
-	{ .csi = RVIN_CSI20, .channel = 1, .vin = 1, .mask = BIT(4) },
-	{ .csi = RVIN_CSI20, .channel = 1, .vin = 2, .mask = BIT(0) },
-	{ .csi = RVIN_CSI40, .channel = 0, .vin = 2, .mask = BIT(1) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 2, .mask = BIT(2) },
-	{ .csi = RVIN_CSI40, .channel = 2, .vin = 2, .mask = BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 2, .vin = 2, .mask = BIT(4) },
-	{ .csi = RVIN_CSI40, .channel = 1, .vin = 3, .mask = BIT(0) },
-	{ .csi = RVIN_CSI20, .channel = 1, .vin = 3, .mask = BIT(1) | BIT(2) },
-	{ .csi = RVIN_CSI40, .channel = 3, .vin = 3, .mask = BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 3, .vin = 3, .mask = BIT(4) },
-	{ .csi = RVIN_CSI41, .channel = 0, .vin = 4, .mask = BIT(0) | BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 4, .mask = BIT(1) | BIT(4) },
-	{ .csi = RVIN_CSI41, .channel = 1, .vin = 4, .mask = BIT(2) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 5, .mask = BIT(0) },
-	{ .csi = RVIN_CSI41, .channel = 1, .vin = 5, .mask = BIT(1) | BIT(3) },
-	{ .csi = RVIN_CSI41, .channel = 0, .vin = 5, .mask = BIT(2) },
-	{ .csi = RVIN_CSI20, .channel = 1, .vin = 5, .mask = BIT(4) },
-	{ .csi = RVIN_CSI20, .channel = 1, .vin = 6, .mask = BIT(0) },
-	{ .csi = RVIN_CSI41, .channel = 0, .vin = 6, .mask = BIT(1) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 6, .mask = BIT(2) },
-	{ .csi = RVIN_CSI41, .channel = 2, .vin = 6, .mask = BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 2, .vin = 6, .mask = BIT(4) },
-	{ .csi = RVIN_CSI41, .channel = 1, .vin = 7, .mask = BIT(0) },
-	{ .csi = RVIN_CSI20, .channel = 1, .vin = 7, .mask = BIT(1) | BIT(2) },
-	{ .csi = RVIN_CSI41, .channel = 3, .vin = 7, .mask = BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 3, .vin = 7, .mask = BIT(4) },
+	{ .master = 0, .csi = RVIN_CSI20, .chsel = 0x04 },
+	{ .master = 0, .csi = RVIN_CSI40, .chsel = 0x03 },
+	{ .master = 4, .csi = RVIN_CSI20, .chsel = 0x04 },
+	{ .master = 4, .csi = RVIN_CSI41, .chsel = 0x03 },
 	{ /* Sentinel */ }
 };
 
@@ -1239,48 +1182,12 @@  static const struct rvin_info rcar_info_r8a7795 = {
 };
 
 static const struct rvin_group_route rcar_info_r8a7795es1_routes[] = {
-	{ .csi = RVIN_CSI40, .channel = 0, .vin = 0, .mask = BIT(0) | BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 0, .mask = BIT(1) | BIT(4) },
-	{ .csi = RVIN_CSI21, .channel = 0, .vin = 0, .mask = BIT(2) | BIT(5) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 1, .mask = BIT(0) },
-	{ .csi = RVIN_CSI21, .channel = 0, .vin = 1, .mask = BIT(1) },
-	{ .csi = RVIN_CSI40, .channel = 0, .vin = 1, .mask = BIT(2) },
-	{ .csi = RVIN_CSI40, .channel = 1, .vin = 1, .mask = BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 1, .vin = 1, .mask = BIT(4) },
-	{ .csi = RVIN_CSI21, .channel = 1, .vin = 1, .mask = BIT(5) },
-	{ .csi = RVIN_CSI21, .channel = 0, .vin = 2, .mask = BIT(0) },
-	{ .csi = RVIN_CSI40, .channel = 0, .vin = 2, .mask = BIT(1) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 2, .mask = BIT(2) },
-	{ .csi = RVIN_CSI40, .channel = 2, .vin = 2, .mask = BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 2, .vin = 2, .mask = BIT(4) },
-	{ .csi = RVIN_CSI21, .channel = 2, .vin = 2, .mask = BIT(5) },
-	{ .csi = RVIN_CSI40, .channel = 1, .vin = 3, .mask = BIT(0) },
-	{ .csi = RVIN_CSI20, .channel = 1, .vin = 3, .mask = BIT(1) },
-	{ .csi = RVIN_CSI21, .channel = 1, .vin = 3, .mask = BIT(2) },
-	{ .csi = RVIN_CSI40, .channel = 3, .vin = 3, .mask = BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 3, .vin = 3, .mask = BIT(4) },
-	{ .csi = RVIN_CSI21, .channel = 3, .vin = 3, .mask = BIT(5) },
-	{ .csi = RVIN_CSI41, .channel = 0, .vin = 4, .mask = BIT(0) | BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 4, .mask = BIT(1) | BIT(4) },
-	{ .csi = RVIN_CSI21, .channel = 0, .vin = 4, .mask = BIT(2) | BIT(5) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 5, .mask = BIT(0) },
-	{ .csi = RVIN_CSI21, .channel = 0, .vin = 5, .mask = BIT(1) },
-	{ .csi = RVIN_CSI41, .channel = 0, .vin = 5, .mask = BIT(2) },
-	{ .csi = RVIN_CSI41, .channel = 1, .vin = 5, .mask = BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 1, .vin = 5, .mask = BIT(4) },
-	{ .csi = RVIN_CSI21, .channel = 1, .vin = 5, .mask = BIT(5) },
-	{ .csi = RVIN_CSI21, .channel = 0, .vin = 6, .mask = BIT(0) },
-	{ .csi = RVIN_CSI41, .channel = 0, .vin = 6, .mask = BIT(1) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 6, .mask = BIT(2) },
-	{ .csi = RVIN_CSI41, .channel = 2, .vin = 6, .mask = BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 2, .vin = 6, .mask = BIT(4) },
-	{ .csi = RVIN_CSI21, .channel = 2, .vin = 6, .mask = BIT(5) },
-	{ .csi = RVIN_CSI41, .channel = 1, .vin = 7, .mask = BIT(0) },
-	{ .csi = RVIN_CSI20, .channel = 1, .vin = 7, .mask = BIT(1) },
-	{ .csi = RVIN_CSI21, .channel = 1, .vin = 7, .mask = BIT(2) },
-	{ .csi = RVIN_CSI41, .channel = 3, .vin = 7, .mask = BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 3, .vin = 7, .mask = BIT(4) },
-	{ .csi = RVIN_CSI21, .channel = 3, .vin = 7, .mask = BIT(5) },
+	{ .master = 0, .csi = RVIN_CSI20, .chsel = 0x04 },
+	{ .master = 0, .csi = RVIN_CSI20, .chsel = 0x05 },
+	{ .master = 0, .csi = RVIN_CSI40, .chsel = 0x03 },
+	{ .master = 4, .csi = RVIN_CSI20, .chsel = 0x04 },
+	{ .master = 4, .csi = RVIN_CSI20, .chsel = 0x05 },
+	{ .master = 4, .csi = RVIN_CSI40, .chsel = 0x03 },
 	{ /* Sentinel */ }
 };
 
@@ -1293,34 +1200,10 @@  static const struct rvin_info rcar_info_r8a7795es1 = {
 };
 
 static const struct rvin_group_route rcar_info_r8a7796_routes[] = {
-	{ .csi = RVIN_CSI40, .channel = 0, .vin = 0, .mask = BIT(0) | BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 0, .mask = BIT(1) | BIT(4) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 1, .mask = BIT(0) },
-	{ .csi = RVIN_CSI40, .channel = 0, .vin = 1, .mask = BIT(2) },
-	{ .csi = RVIN_CSI40, .channel = 1, .vin = 1, .mask = BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 1, .vin = 1, .mask = BIT(4) },
-	{ .csi = RVIN_CSI40, .channel = 0, .vin = 2, .mask = BIT(1) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 2, .mask = BIT(2) },
-	{ .csi = RVIN_CSI40, .channel = 2, .vin = 2, .mask = BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 2, .vin = 2, .mask = BIT(4) },
-	{ .csi = RVIN_CSI40, .channel = 1, .vin = 3, .mask = BIT(0) },
-	{ .csi = RVIN_CSI20, .channel = 1, .vin = 3, .mask = BIT(1) },
-	{ .csi = RVIN_CSI40, .channel = 3, .vin = 3, .mask = BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 3, .vin = 3, .mask = BIT(4) },
-	{ .csi = RVIN_CSI40, .channel = 0, .vin = 4, .mask = BIT(0) | BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 4, .mask = BIT(1) | BIT(4) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 5, .mask = BIT(0) },
-	{ .csi = RVIN_CSI40, .channel = 0, .vin = 5, .mask = BIT(2) },
-	{ .csi = RVIN_CSI40, .channel = 1, .vin = 5, .mask = BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 1, .vin = 5, .mask = BIT(4) },
-	{ .csi = RVIN_CSI40, .channel = 0, .vin = 6, .mask = BIT(1) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 6, .mask = BIT(2) },
-	{ .csi = RVIN_CSI40, .channel = 2, .vin = 6, .mask = BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 2, .vin = 6, .mask = BIT(4) },
-	{ .csi = RVIN_CSI40, .channel = 1, .vin = 7, .mask = BIT(0) },
-	{ .csi = RVIN_CSI20, .channel = 1, .vin = 7, .mask = BIT(1) },
-	{ .csi = RVIN_CSI40, .channel = 3, .vin = 7, .mask = BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 3, .vin = 7, .mask = BIT(4) },
+	{ .master = 0, .csi = RVIN_CSI20, .chsel = 0x04 },
+	{ .master = 0, .csi = RVIN_CSI40, .chsel = 0x03 },
+	{ .master = 4, .csi = RVIN_CSI20, .chsel = 0x04 },
+	{ .master = 4, .csi = RVIN_CSI40, .chsel = 0x03 },
 	{ /* Sentinel */ }
 };
 
@@ -1334,38 +1217,10 @@  static const struct rvin_info rcar_info_r8a7796 = {
 };
 
 static const struct rvin_group_route rcar_info_r8a77965_routes[] = {
-	{ .csi = RVIN_CSI40, .channel = 0, .vin = 0, .mask = BIT(0) | BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 0, .mask = BIT(1) | BIT(4) },
-	{ .csi = RVIN_CSI40, .channel = 1, .vin = 0, .mask = BIT(2) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 1, .mask = BIT(0) },
-	{ .csi = RVIN_CSI40, .channel = 1, .vin = 1, .mask = BIT(1) | BIT(3) },
-	{ .csi = RVIN_CSI40, .channel = 0, .vin = 1, .mask = BIT(2) },
-	{ .csi = RVIN_CSI20, .channel = 1, .vin = 1, .mask = BIT(4) },
-	{ .csi = RVIN_CSI20, .channel = 1, .vin = 2, .mask = BIT(0) },
-	{ .csi = RVIN_CSI40, .channel = 0, .vin = 2, .mask = BIT(1) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 2, .mask = BIT(2) },
-	{ .csi = RVIN_CSI40, .channel = 2, .vin = 2, .mask = BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 2, .vin = 2, .mask = BIT(4) },
-	{ .csi = RVIN_CSI40, .channel = 1, .vin = 3, .mask = BIT(0) },
-	{ .csi = RVIN_CSI20, .channel = 1, .vin = 3, .mask = BIT(1) | BIT(2) },
-	{ .csi = RVIN_CSI40, .channel = 3, .vin = 3, .mask = BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 3, .vin = 3, .mask = BIT(4) },
-	{ .csi = RVIN_CSI40, .channel = 0, .vin = 4, .mask = BIT(0) | BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 4, .mask = BIT(1) | BIT(4) },
-	{ .csi = RVIN_CSI40, .channel = 1, .vin = 4, .mask = BIT(2) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 5, .mask = BIT(0) },
-	{ .csi = RVIN_CSI40, .channel = 1, .vin = 5, .mask = BIT(1) | BIT(3) },
-	{ .csi = RVIN_CSI40, .channel = 0, .vin = 5, .mask = BIT(2) },
-	{ .csi = RVIN_CSI20, .channel = 1, .vin = 5, .mask = BIT(4) },
-	{ .csi = RVIN_CSI20, .channel = 1, .vin = 6, .mask = BIT(0) },
-	{ .csi = RVIN_CSI40, .channel = 0, .vin = 6, .mask = BIT(1) },
-	{ .csi = RVIN_CSI20, .channel = 0, .vin = 6, .mask = BIT(2) },
-	{ .csi = RVIN_CSI40, .channel = 2, .vin = 6, .mask = BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 2, .vin = 6, .mask = BIT(4) },
-	{ .csi = RVIN_CSI40, .channel = 1, .vin = 7, .mask = BIT(0) },
-	{ .csi = RVIN_CSI20, .channel = 1, .vin = 7, .mask = BIT(1) | BIT(2) },
-	{ .csi = RVIN_CSI40, .channel = 3, .vin = 7, .mask = BIT(3) },
-	{ .csi = RVIN_CSI20, .channel = 3, .vin = 7, .mask = BIT(4) },
+	{ .master = 0, .csi = RVIN_CSI20, .chsel = 0x04 },
+	{ .master = 0, .csi = RVIN_CSI40, .chsel = 0x03 },
+	{ .master = 4, .csi = RVIN_CSI20, .chsel = 0x04 },
+	{ .master = 4, .csi = RVIN_CSI40, .chsel = 0x03 },
 	{ /* Sentinel */ }
 };
 
@@ -1379,13 +1234,7 @@  static const struct rvin_info rcar_info_r8a77965 = {
 };
 
 static const struct rvin_group_route rcar_info_r8a77970_routes[] = {
-	{ .csi = RVIN_CSI40, .channel = 0, .vin = 0, .mask = BIT(0) | BIT(3) },
-	{ .csi = RVIN_CSI40, .channel = 0, .vin = 1, .mask = BIT(2) },
-	{ .csi = RVIN_CSI40, .channel = 1, .vin = 1, .mask = BIT(3) },
-	{ .csi = RVIN_CSI40, .channel = 0, .vin = 2, .mask = BIT(1) },
-	{ .csi = RVIN_CSI40, .channel = 2, .vin = 2, .mask = BIT(3) },
-	{ .csi = RVIN_CSI40, .channel = 1, .vin = 3, .mask = BIT(0) },
-	{ .csi = RVIN_CSI40, .channel = 3, .vin = 3, .mask = BIT(3) },
+	{ .master = 0, .csi = RVIN_CSI40, .chsel = 0x03 },
 	{ /* Sentinel */ }
 };
 
@@ -1398,22 +1247,8 @@  static const struct rvin_info rcar_info_r8a77970 = {
 };
 
 static const struct rvin_group_route rcar_info_r8a77980_routes[] = {
-	{ .csi = RVIN_CSI40, .channel = 0, .vin = 0, .mask = BIT(0) | BIT(3) },
-	{ .csi = RVIN_CSI40, .channel = 1, .vin = 0, .mask = BIT(2) },
-	{ .csi = RVIN_CSI40, .channel = 0, .vin = 1, .mask = BIT(2) },
-	{ .csi = RVIN_CSI40, .channel = 1, .vin = 1, .mask = BIT(1) | BIT(3) },
-	{ .csi = RVIN_CSI40, .channel = 0, .vin = 2, .mask = BIT(1) },
-	{ .csi = RVIN_CSI40, .channel = 2, .vin = 2, .mask = BIT(3) },
-	{ .csi = RVIN_CSI40, .channel = 1, .vin = 3, .mask = BIT(0) },
-	{ .csi = RVIN_CSI40, .channel = 3, .vin = 3, .mask = BIT(3) },
-	{ .csi = RVIN_CSI41, .channel = 0, .vin = 4, .mask = BIT(0) | BIT(3) },
-	{ .csi = RVIN_CSI41, .channel = 1, .vin = 4, .mask = BIT(2) },
-	{ .csi = RVIN_CSI41, .channel = 0, .vin = 5, .mask = BIT(2) },
-	{ .csi = RVIN_CSI41, .channel = 1, .vin = 5, .mask = BIT(1) | BIT(3) },
-	{ .csi = RVIN_CSI41, .channel = 0, .vin = 6, .mask = BIT(1) },
-	{ .csi = RVIN_CSI41, .channel = 2, .vin = 6, .mask = BIT(3) },
-	{ .csi = RVIN_CSI41, .channel = 1, .vin = 7, .mask = BIT(0) },
-	{ .csi = RVIN_CSI41, .channel = 3, .vin = 7, .mask = BIT(3) },
+	{ .master = 0, .csi = RVIN_CSI40, .chsel = 0x03 },
+	{ .master = 4, .csi = RVIN_CSI41, .chsel = 0x03 },
 	{ /* Sentinel */ }
 };
 
@@ -1427,10 +1262,7 @@  static const struct rvin_info rcar_info_r8a77980 = {
 };
 
 static const struct rvin_group_route rcar_info_r8a77990_routes[] = {
-	{ .csi = RVIN_CSI40, .channel = 0, .vin = 4, .mask = BIT(0) | BIT(3) },
-	{ .csi = RVIN_CSI40, .channel = 0, .vin = 5, .mask = BIT(2) },
-	{ .csi = RVIN_CSI40, .channel = 1, .vin = 4, .mask = BIT(2) },
-	{ .csi = RVIN_CSI40, .channel = 1, .vin = 5, .mask = BIT(1) | BIT(3) },
+	{ .master = 0, .csi = RVIN_CSI40, .chsel = 0x03 },
 	{ /* Sentinel */ }
 };
 
diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c b/drivers/media/platform/rcar-vin/rcar-csi2.c
index 11848d0c4a55cb4c..b8c56d248454efbf 100644
--- a/drivers/media/platform/rcar-vin/rcar-csi2.c
+++ b/drivers/media/platform/rcar-vin/rcar-csi2.c
@@ -468,6 +468,8 @@  struct rcar_csi2 {
 	struct v4l2_subdev *remote;
 	unsigned int remote_pad;
 
+	int channel_vc[4];
+
 	struct mutex lock; /* Protects mf and stream_count. */
 	struct v4l2_mbus_framefmt mf;
 	int stream_count;
@@ -664,8 +666,11 @@  static int rcsi2_start_receiver(struct rcar_csi2 *priv)
 	for (i = 0; i < priv->info->num_channels; i++) {
 		u32 vcdt_part;
 
-		vcdt_part = VCDT_SEL_VC(i) | VCDT_VCDTN_EN | VCDT_SEL_DTN_ON |
-			VCDT_SEL_DT(format->datatype);
+		if (priv->channel_vc[i] < 0)
+			continue;
+
+		vcdt_part = VCDT_SEL_VC(priv->channel_vc[i]) | VCDT_VCDTN_EN |
+			VCDT_SEL_DTN_ON | VCDT_SEL_DT(format->datatype);
 
 		/* Store in correct reg and offset. */
 		if (i < 2)
@@ -1240,7 +1245,53 @@  static int rcsi2_init_phtw_v3u(struct rcar_csi2 *priv,
  * Platform Device Driver.
  */
 
+static int rcsi2_link_setup(struct media_entity *entity,
+			    const struct media_pad *local,
+			    const struct media_pad *remote, u32 flags)
+{
+	struct v4l2_subdev *sd = media_entity_to_v4l2_subdev(entity);
+	struct rcar_csi2 *priv = sd_to_csi2(sd);
+	struct video_device *vdev;
+	int channel, vc;
+	u32 id;
+
+	if (!is_media_entity_v4l2_video_device(remote->entity)) {
+		dev_err(priv->dev, "Remote is not a video device\n");
+		return -EINVAL;
+	}
+
+	vdev = media_entity_to_video_device(remote->entity);
+
+	if (of_property_read_u32(vdev->dev_parent->of_node, "renesas,id", &id)) {
+		dev_err(priv->dev, "No renesas,id, can't configure routing\n");
+		return -EINVAL;
+	}
+
+	channel = id % 4;
+
+	if (flags & MEDIA_LNK_FL_ENABLED) {
+		if (media_entity_remote_pad(local)) {
+			dev_dbg(priv->dev,
+				"Each VC can only be routed to one output channel\n");
+			return -EINVAL;
+		}
+
+		vc = local->index - 1;
+
+		dev_dbg(priv->dev, "Route VC%d to VIN%u on output channel %d\n",
+			vc, id, channel);
+	} else {
+		vc = -1;
+	}
+
+	priv->channel_vc[channel] = vc;
+
+	return 0;
+}
+
+
 static const struct media_entity_operations rcar_csi2_entity_ops = {
+	.link_setup = rcsi2_link_setup,
 	.link_validate = v4l2_subdev_link_validate,
 };
 
@@ -1459,6 +1510,9 @@  static int rcsi2_probe(struct platform_device *pdev)
 	if (ret)
 		goto error_async;
 
+	for (i = 0; i < ARRAY_SIZE(priv->channel_vc); i++)
+		priv->channel_vc[i] = -1;
+
 	pm_runtime_enable(&pdev->dev);
 
 	ret = v4l2_async_register_subdev(&priv->subdev);
diff --git a/drivers/media/platform/rcar-vin/rcar-dma.c b/drivers/media/platform/rcar-vin/rcar-dma.c
index 25ead9333d0046e7..b72ae27a407dc96c 100644
--- a/drivers/media/platform/rcar-vin/rcar-dma.c
+++ b/drivers/media/platform/rcar-vin/rcar-dma.c
@@ -1490,7 +1490,7 @@  int rvin_set_channel_routing(struct rvin_dev *vin, u8 chsel)
 	 * register. IFMD_DES1 controls data expansion mode for CSI20/21,
 	 * IFMD_DES0 controls data expansion mode for CSI40/41.
 	 */
-	for (route = vin->info->routes; route->mask; route++) {
+	for (route = vin->info->routes; route->chsel; route++) {
 		if (route->csi == RVIN_CSI20 || route->csi == RVIN_CSI21)
 			ifmd |= VNCSI_IFMD_DES1;
 		else
diff --git a/drivers/media/platform/rcar-vin/rcar-vin.h b/drivers/media/platform/rcar-vin/rcar-vin.h
index 6c06320174a2ed96..ddc1830be9a5d6c3 100644
--- a/drivers/media/platform/rcar-vin/rcar-vin.h
+++ b/drivers/media/platform/rcar-vin/rcar-vin.h
@@ -128,11 +128,9 @@  struct rvin_parallel_entity {
  * struct rvin_group_route - describes a route from a channel of a
  *	CSI-2 receiver to a VIN
  *
+ * @master:	VIN group master ID.
  * @csi:	CSI-2 receiver ID.
- * @channel:	Output channel of the CSI-2 receiver.
- * @vin:	VIN ID.
- * @mask:	Bitmask of the different CHSEL register values that
- *		allow for a route from @csi + @chan to @vin.
+ * @chsel:	CHSEL register values that connects VIN group to CSI-2.
  *
  * .. note::
  *	Each R-Car CSI-2 receiver has four output channels facing the VIN
@@ -140,19 +138,11 @@  struct rvin_parallel_entity {
  *	There is no correlation between channel number and CSI-2 VC. It's
  *	up to the CSI-2 receiver driver to configure which VC is output
  *	on which channel, the VIN devices only care about output channels.
- *
- *	There are in some cases multiple CHSEL register settings which would
- *	allow for the same route from @csi + @channel to @vin. For example
- *	on R-Car H3 both the CHSEL values 0 and 3 allow for a route from
- *	CSI40/VC0 to VIN0. All possible CHSEL values for a route need to be
- *	recorded as a bitmask in @mask, in this example bit 0 and 3 should
- *	be set.
  */
 struct rvin_group_route {
+	unsigned int master;
 	enum rvin_csi_id csi;
-	unsigned int channel;
-	unsigned int vin;
-	unsigned int mask;
+	unsigned int chsel;
 };
 
 /**