Hi Niklas,
On Wed, Oct 20, 2021 at 10:02:23PM +0200, Niklas Söderlund wrote:
> The code have grown organically and a lot of checks are preformed for
code -> has
preformed -> performed
> the CSI-2 use-case even if the link notify is for a subdevice connected
> to the parallel interface.
>
> Before reworking the CSI-2 routing logic split the CSI-2 and parallel
> link notify code in two separate blocks to make it clearer. There is no
> functional change.
>
> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx>
> ---
> drivers/media/platform/rcar-vin/rcar-core.c | 87 +++++++++++----------
> 1 file changed, 45 insertions(+), 42 deletions(-)
>
> diff --git a/drivers/media/platform/rcar-vin/rcar-core.c b/drivers/media/platform/rcar-vin/rcar-core.c
> index 1d92cc8ede8f8a3e..bd960c348ba5228c 100644
> --- a/drivers/media/platform/rcar-vin/rcar-core.c
> +++ b/drivers/media/platform/rcar-vin/rcar-core.c
> @@ -795,12 +795,10 @@ static int rvin_csi2_link_notify(struct media_link *link, u32 flags,
> {
> struct rvin_group *group = container_of(link->graph_obj.mdev,
> struct rvin_group, mdev);
> - unsigned int master_id, channel, mask_new, i;
> - unsigned int mask = ~0;
> struct media_entity *entity;
> struct video_device *vdev;
> - struct media_pad *csi_pad;
> - struct rvin_dev *vin = NULL;
> + struct rvin_dev *vin;
> + unsigned int i;
> int csi_id, ret;
>
> ret = v4l2_pipeline_link_notify(link, flags, notification);
> @@ -826,33 +824,9 @@ static int rvin_csi2_link_notify(struct media_link *link, u32 flags,
> /* Find the master VIN that controls the routes. */
> vdev = media_entity_to_video_device(link->sink->entity);
> vin = container_of(vdev, struct rvin_dev, vdev);
> - master_id = rvin_group_id_to_master(vin->id);
>
> - if (WARN_ON(!group->vin[master_id])) {
> - ret = -ENODEV;
> - goto out;
> - }
>
> - /* Build a mask for already enabled links. */
> - for (i = master_id; i < master_id + 4; i++) {
> - 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;
> -
> - 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);
> - }
> -
There are now two empty lines here
> - /* Add the new link to the existing mask and check if it works. */
> csi_id = rvin_group_entity_to_remote_id(group, link->source->entity);
> -
> if (csi_id == -ENODEV) {
> struct v4l2_subdev *sd;
>
> @@ -877,25 +851,54 @@ static int rvin_csi2_link_notify(struct media_link *link, u32 flags,
> vin_err(vin, "Subdevice %s not registered to any VIN\n",
> link->source->entity->name);
> ret = -ENODEV;
> - goto out;
> - }
> + } else {
I wonder if the group mutex should be locked in the else branch only
and simplify the whole thing as:
if (csi_id == -ENODEV) {
/* subdev is parallel. */
for () {
return 0;
}
return -ENODEV;
}
/* subdev is CSI-2 */
mutex_lock(group->mutex);
...
mutex_unlock(group->mutex);
Even if I see above:
/*
* Don't allow link changes if any stream in the graph is active as
* modifying the CHSEL register fields can disrupt running streams.
*/
media_device_for_each_entity(entity, &group->mdev) {
struct media_pad *iter;
media_entity_for_each_pad(entity, iter) {
if (iter->stream_count)
return -EBUSY;
}
}
Being run out of the critical session, but that was already the case.
> + unsigned int master_id, channel, mask_new;
> + unsigned int mask = ~0;
> + struct media_pad *csi_pad;
>
> - 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);
> + master_id = rvin_group_id_to_master(vin->id);
>
> - if (!mask_new) {
> - ret = -EMLINK;
> - goto out;
> - }
> + if (WARN_ON(!group->vin[master_id])) {
> + ret = -ENODEV;
> + goto out;
> + }
> +
> + /* Build a mask for already enabled links. */
> + for (i = master_id; i < master_id + 4; i++) {
> + 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;
>
> - /* New valid CHSEL found, set the new value. */
> - ret = rvin_set_channel_routing(group->vin[master_id], __ffs(mask_new));
> - if (ret)
> - goto out;
> + csi_id = rvin_group_entity_to_remote_id(group,
> + csi_pad->entity);
> + channel = rvin_group_csi_pad_to_channel(csi_pad->index);
>
> - vin->is_csi = true;
> + mask &= rvin_csi2_get_mask(group->vin[i], csi_id, channel);
> + }
>
> + 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;
> + }
> +
> + /* New valid CHSEL found, set the new value. */
> + ret = rvin_set_channel_routing(group->vin[master_id],
> + __ffs(mask_new));
> + if (ret)
> + goto out;
> +
> + vin->is_csi = true;
> + }
> out:
> mutex_unlock(&group->lock);
>
> --
> 2.33.1
>
