[2/4] media: camss: vfe: Reserve VFE lines on stream start and link to CSID

From: Milen Mitkov <quic_mmitkov@quicinc.com>

For multiple virtual channels support, each VFE line can be in either
ON, RESERVED or OFF states. This allows the starting and stopping
of a VFE line independently of other active VFE lines.

Also, link the CSID entity's source ports to corresponding VFE lines.

Signed-off-by: Milen Mitkov <quic_mmitkov@quicinc.com>
---
 drivers/media/platform/qcom/camss/camss-vfe.c | 7 +++++++
 drivers/media/platform/qcom/camss/camss.c     | 2 +-
 2 files changed, 8 insertions(+), 1 deletion(-)

On Mon, 26 Sept 2022 at 16:25, <quic_mmitkov@quicinc.com> wrote:
>
> From: Milen Mitkov <quic_mmitkov@quicinc.com>
>
> For multiple virtual channels support, each VFE line can be in either
> ON, RESERVED or OFF states. This allows the starting and stopping
> of a VFE line independently of other active VFE lines.
>
> Also, link the CSID entity's source ports to corresponding VFE lines.
>
> Signed-off-by: Milen Mitkov <quic_mmitkov@quicinc.com>
> ---
>  drivers/media/platform/qcom/camss/camss-vfe.c | 7 +++++++
>  drivers/media/platform/qcom/camss/camss.c     | 2 +-
>  2 files changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/media/platform/qcom/camss/camss-vfe.c b/drivers/media/platform/qcom/camss/camss-vfe.c
> index a26e4a5d87b6..cd8ac0478cf1 100644
> --- a/drivers/media/platform/qcom/camss/camss-vfe.c
> +++ b/drivers/media/platform/qcom/camss/camss-vfe.c
> @@ -738,8 +738,10 @@ static int vfe_set_stream(struct v4l2_subdev *sd, int enable)
>         struct vfe_line *line = v4l2_get_subdevdata(sd);
>         struct vfe_device *vfe = to_vfe(line);
>         int ret;
> +       int i;
>
>         if (enable) {
> +               line->output.state = VFE_OUTPUT_RESERVED;
>                 ret = vfe->ops->vfe_enable(line);
>                 if (ret < 0)
>                         dev_err(vfe->camss->dev,
> @@ -749,6 +751,11 @@ static int vfe_set_stream(struct v4l2_subdev *sd, int enable)
>                 if (ret < 0)
>                         dev_err(vfe->camss->dev,
>                                 "Failed to disable vfe outputs\n");
> +
> +               /* At least one VFE line remains, return -EBUSY to avoid premature pipeline stop */
> +               for (i = 0; i < vfe->line_num; i++)
> +                       if (vfe->line[i].output.state != VFE_OUTPUT_OFF)
> +                               return -EBUSY;
>         }
>
>         return ret;
> diff --git a/drivers/media/platform/qcom/camss/camss.c b/drivers/media/platform/qcom/camss/camss.c
> index 1118c40886d5..63653ac3e056 100644
> --- a/drivers/media/platform/qcom/camss/camss.c
> +++ b/drivers/media/platform/qcom/camss/camss.c
> @@ -1320,7 +1320,7 @@ static int camss_register_entities(struct camss *camss)
>                                         struct v4l2_subdev *vfe = &camss->vfe[k].line[j].subdev;
>
>                                         ret = media_create_pad_link(&csid->entity,
> -                                                                   MSM_CSID_PAD_SRC,
> +                                                                   MSM_CSID_PAD_FIRST_SRC + j,
>                                                                     &vfe->entity,
>                                                                     MSM_VFE_PAD_SINK,
>                                                                     0);
> --
> 2.37.3
>

Reviewed-by: Robert Foss <robert.foss@linaro.org>