Re: [PATCH 2/5] dt-bindings: media: add i.MX parallel csi support

[Frank Li]

On Tue, Jul 01, 2025 at 01:53:40AM +0300, Laurent Pinchart wrote:
> Hi Frank, Alice,
>
> Thank you for the patch.
>
> On Mon, Jun 30, 2025 at 06:28:18PM -0400, Frank Li wrote:
> > From: Alice Yuan <alice.yuan@xxxxxxx>
> >
> > Document the binding for parallel CSI controller found in i.MX8QXP, i.MX93
> > and i.MX91 SoCs.
> >
> > Signed-off-by: Alice Yuan <alice.yuan@xxxxxxx>
> > Signed-off-by: Frank Li <Frank.Li@xxxxxxx>
> > ---
> >  .../bindings/media/fsl,imx93-parallel-csi.yaml     | 108 +++++++++++++++++++++
> >  MAINTAINERS                                        |   1 +
> >  2 files changed, 109 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/media/fsl,imx93-parallel-csi.yaml b/Documentation/devicetree/bindings/media/fsl,imx93-parallel-csi.yaml
> > new file mode 100644
> > index 0000000000000..b4657c913adad
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/media/fsl,imx93-parallel-csi.yaml
> > @@ -0,0 +1,108 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/media/fsl,imx93-parallel-csi.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: i.MX8/9 Parallel Camera Interface
> > +
> > +maintainers:
> > +  - Frank Li <Frank.Li@xxxxxxx>
> > +
> > +description: |
> > +  This is device node for the Parallel Camera Interface which enables the
> > +  chip to connect directly to external Parallel CMOS image sensors.
> > +  Supports up to 80MHz input clock from sensor.
> > +  Supports the following input data formats
> > +    - 8-bit/10-bit Camera Sensor Interface (CSI)
> > +    - 8-bit data port for RGB, YCbCr, and YUV data input
> > +    - 8-bit/10-bit data ports for Bayer data input
> > +  Parallel Camera Interface is hooked to the Imaging subsystem via the
> > +  Pixel Link.
> > +
> > +properties:
> > +  compatible:
> > +    oneOf:
> > +      - const: fsl,imx8qxp-parallel-csi
>
> Is there any chance we could avoid calling this "csi", given that the
> whole block is called "Parallel Capture Interface" in the reference
> manual ? "CSI" is horribly confusing as it usually refers to MIPI CSI-2.
> I suppose calling it "PCI" for "Parallel Capture Interface" wouldn't
> help :-/

PCI is too famous for PCI(Peripheral Component Interconnec) bus. It will be
more confused.

Can we use pcam? fsl,imx8qxp-pcam

Frank

>
> > +      - items:
> > +          - enum:
> > +              - fsl,imx91-parallel-csi
> > +          - const: fsl,imx93-parallel-csi
> > +      - const: fsl,imx93-parallel-csi
> > +
> > +  reg:
> > +    maxItems: 1
> > +
> > +  clocks:
> > +    maxItems: 2
> > +
> > +  clock-names:
> > +    items:
> > +      - const: pixel
> > +      - const: ipg
> > +
> > +  power-domains:
> > +    maxItems: 1
> > +
> > +  ports:
> > +    $ref: /schemas/graph.yaml#/properties/ports
> > +
> > +    properties:
> > +      port@0:
> > +        $ref: /schemas/graph.yaml#/$defs/port-base
> > +        unevaluatedProperties: false
> > +        description:
> > +          Input port node.
> > +
> > +      port@1:
> > +        $ref: /schemas/graph.yaml#/$defs/port-base
> > +        unevaluatedProperties: false
> > +        description:
> > +          Output port node.
> > +
> > +required:
> > +  - compatible
> > +  - reg
> > +  - clocks
> > +  - clock-names
> > +  - ports
>
> Patch 4/5 lists a power domain, and so does the example below for
> i.MX93. Should the power-domains property be mandatory ?
>
> > +
> > +additionalProperties: false
> > +
> > +examples:
> > +  - |
> > +    #include <dt-bindings/clock/imx93-clock.h>
> > +    #include <dt-bindings/power/fsl,imx93-power.h>
> > +
> > +    parallel-csi@4ac10070 {
> > +        compatible = "fsl,imx93-parallel-csi";
> > +        reg = <0x4ac10070 0x10>;
>
> The i.MX93 reference manual doesn't document the register set for this
> block, so I have a hard time reviewing this. Is there a plan to publish
> a new version of the reference manual with the complete documentation
> for the parallel interface ?
>
> > +        clocks = <&clk IMX93_CLK_MIPI_CSI_GATE>,
> > +                 <&clk IMX93_CLK_MEDIA_APB>;
> > +        clock-names = "pixel", "ipg";
> > +        assigned-clocks = <&clk IMX93_CLK_CAM_PIX>;
> > +        assigned-clock-parents = <&clk IMX93_CLK_VIDEO_PLL>;
> > +        assigned-clock-rates = <140000000>;
> > +        power-domains = <&media_blk_ctrl IMX93_MEDIABLK_PD_MIPI_CSI>;
> > +
> > +        ports {
> > +            #address-cells = <1>;
> > +            #size-cells = <0>;
> > +
> > +            port@0 {
> > +                reg = <0>;
> > +
> > +                endpoint {
> > +                    remote-endpoint = <&mt9m114_ep>;
> > +                };
> > +            };
> > +
> > +            port@1 {
> > +                reg = <1>;
> > +                endpoint {
> > +                    remote-endpoint = <&isi_in>;
> > +                };
> > +            };
> > +        };
> > +    };
> > +...
> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index 8dc0f6609d1fe..3bd6772c11539 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -15107,6 +15107,7 @@ L:	linux-media@xxxxxxxxxxxxxxx
> >  S:	Maintained
> >  T:	git git://linuxtv.org/media.git
> >  F:	Documentation/admin-guide/media/imx7.rst
> > +F:	Documentation/devicetree/bindings/media/fsl,imx93-parallel-csi.yaml
> >  F:	Documentation/devicetree/bindings/media/nxp,imx-mipi-csi2.yaml
> >  F:	Documentation/devicetree/bindings/media/nxp,imx7-csi.yaml
> >  F:	Documentation/devicetree/bindings/media/nxp,imx8mq-mipi-csi2.yaml
>
> --
> Regards,
>
> Laurent Pinchart