[v2,1/4] media: imx.rst: Fix the MIPI CSI-2 virtual channel

  The current instructions for imx6q-sabresd do not lead to functional
capture on OV5640 MIPI CSI-2.

The reason for this, as explained by Steve Longerbeam, is that OV5640 by
default transmits on virtual channel 0, not channel 1 as is given in the
instructions.

Adapt the instructions to use virtual channel 0 so that a working
camera setup can be achieved on imx6q-sabresd.

Also, since we are using an IC direct conversion pipeline, improve
the example by demonstrating colorspace and scaling.

Signed-off-by: Fabio Estevam <festevam@gmail.com>
---
Changes since v1:
- Demonstrate colorspace and scaling. (Steve)

 Documentation/media/v4l-drivers/imx.rst | 31 ++++++++++++-------------
 1 file changed, 15 insertions(+), 16 deletions(-)
  

On 4/9/20 9:29 AM, Fabio Estevam wrote:
> The current instructions for imx6q-sabresd do not lead to functional
> capture on OV5640 MIPI CSI-2.
>
> The reason for this, as explained by Steve Longerbeam, is that OV5640 by
> default transmits on virtual channel 0, not channel 1 as is given in the
> instructions.
>
> Adapt the instructions to use virtual channel 0 so that a working
> camera setup can be achieved on imx6q-sabresd.
>
> Also, since we are using an IC direct conversion pipeline, improve
> the example by demonstrating colorspace and scaling.
>
> Signed-off-by: Fabio Estevam <festevam@gmail.com>

Reviewed-by: Steve Longerbeam<slongerbeam@gmail.com>

> ---
> Changes since v1:
> - Demonstrate colorspace and scaling. (Steve)
>
>   Documentation/media/v4l-drivers/imx.rst | 31 ++++++++++++-------------
>   1 file changed, 15 insertions(+), 16 deletions(-)
>
> diff --git a/Documentation/media/v4l-drivers/imx.rst b/Documentation/media/v4l-drivers/imx.rst
> index 1246573c1019..b8df91f83f14 100644
> --- a/Documentation/media/v4l-drivers/imx.rst
> +++ b/Documentation/media/v4l-drivers/imx.rst
> @@ -645,30 +645,29 @@ The OV5640 module connects to MIPI connector J5 (sorry I don't have the
>   compatible module part number or URL).
>   
>   The following example configures a direct conversion pipeline to capture
> -from the OV5640, transmitting on MIPI CSI-2 virtual channel 1. $sensorfmt
> -can be any format supported by the OV5640. $sensordim is the frame
> -dimension part of $sensorfmt (minus the mbus pixel code). $outputfmt can
> -be any format supported by the ipu1_ic_prpenc entity at its output pad:
> +from the OV5640, transmitting on MIPI CSI-2 virtual channel 0. It also
> +shows colorspace conversion and scaling at IC output.
>   
>   .. code-block:: none
>   
>      # Setup links
>      media-ctl -l "'ov5640 1-003c':0 -> 'imx6-mipi-csi2':0[1]"
> -   media-ctl -l "'imx6-mipi-csi2':2 -> 'ipu1_csi1':0[1]"
> -   media-ctl -l "'ipu1_csi1':1 -> 'ipu1_ic_prp':0[1]"
> +   media-ctl -l "'imx6-mipi-csi2':1 -> 'ipu1_csi0_mux':0[1]"
> +   media-ctl -l "'ipu1_csi0_mux':2 -> 'ipu1_csi0':0[1]"
> +   media-ctl -l "'ipu1_csi0':1 -> 'ipu1_ic_prp':0[1]"
>      media-ctl -l "'ipu1_ic_prp':1 -> 'ipu1_ic_prpenc':0[1]"
>      media-ctl -l "'ipu1_ic_prpenc':1 -> 'ipu1_ic_prpenc capture':0[1]"
>      # Configure pads
> -   media-ctl -V "'ov5640 1-003c':0 [fmt:$sensorfmt field:none]"
> -   media-ctl -V "'imx6-mipi-csi2':2 [fmt:$sensorfmt field:none]"
> -   media-ctl -V "'ipu1_csi1':1 [fmt:AYUV32/$sensordim field:none]"
> -   media-ctl -V "'ipu1_ic_prp':1 [fmt:AYUV32/$sensordim field:none]"
> -   media-ctl -V "'ipu1_ic_prpenc':1 [fmt:$outputfmt field:none]"
> -
> -Streaming can then begin on "ipu1_ic_prpenc capture" node. The v4l2-ctl
> -tool can be used to select any supported YUV or RGB pixelformat on the
> -capture device node.
> -
> +   media-ctl -V "'ov5640 1-003c':0 [fmt:UYVY2X8/640x480]"
> +   media-ctl -V "'imx6-mipi-csi2':1 [fmt:UYVY2X8/640x480]"
> +   media-ctl -V "'ipu1_csi0_mux':2 [fmt:UYVY2X8/640x480]"
> +   media-ctl -V "'ipu1_csi0':1 [fmt:AYUV32/640x480]"
> +   media-ctl -V "'ipu1_ic_prp':1 [fmt:AYUV32/640x480]"
> +   media-ctl -V "'ipu1_ic_prpenc':1 [fmt:ARGB8888_1X32/800x600]"
> +   # Set a format at the capture interface
> +   v4l2-ctl -d /dev/video1 --set-fmt-video=pixelformat=RGB3
> +
> +Streaming can then begin on "ipu1_ic_prpenc capture" node.
>   
>   Known Issues
>   ------------