Re: [PATCH v4 6/8] media: dt-bindings: Add bindings for JH7110 Camera Subsystem

[Laurent Pinchart]

Hi Jack,

On Thu, Apr 20, 2023 at 04:51:39PM +0800, Jack Zhu wrote:
> On 2023/4/19 14:15, Laurent Pinchart wrote:
> > On Thu, Apr 13, 2023 at 11:55:39AM +0800, Jack Zhu wrote:
> >> Add the bindings documentation for Starfive JH7110 Camera Subsystem
> >> which is used for handing image sensor data.
> >> 
> >> Signed-off-by: Jack Zhu <jack.zhu@xxxxxxxxxxxxxxxx>
> >> ---
> >>  .../bindings/media/starfive,jh7110-camss.yaml | 164 ++++++++++++++++++
> >>  MAINTAINERS                                   |   7 +
> >>  2 files changed, 171 insertions(+)
> >>  create mode 100644 Documentation/devicetree/bindings/media/starfive,jh7110-camss.yaml
> >> 
> >> diff --git a/Documentation/devicetree/bindings/media/starfive,jh7110-camss.yaml b/Documentation/devicetree/bindings/media/starfive,jh7110-camss.yaml
> >> new file mode 100644
> >> index 000000000000..4cd144f1b845
> >> --- /dev/null
> >> +++ b/Documentation/devicetree/bindings/media/starfive,jh7110-camss.yaml
> >> @@ -0,0 +1,164 @@
> >> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> >> +
> >> +%YAML 1.2
> >> +---
> >> +$id: http://devicetree.org/schemas/media/starfive,jh7110-camss.yaml#
> >> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> >> +
> >> +title: Starfive SoC CAMSS ISP
> >> +
> >> +maintainers:
> >> +  - Jack Zhu <jack.zhu@xxxxxxxxxxxxxxxx>
> >> +  - Changhuang Liang <changhuang.liang@xxxxxxxxxxxxxxxx>
> >> +
> >> +description:
> >> +  The Starfive CAMSS ISP is a Camera interface for Starfive JH7110 SoC. It
> >> +  consists of a VIN controller (Video In Controller, a top-level control until)
> >> +  and an ISP.
> >> +
> >> +properties:
> >> +  compatible:
> >> +    const: starfive,jh7110-camss
> >> +
> >> +  reg:
> >> +    maxItems: 2
> >> +
> >> +  reg-names:
> >> +    items:
> >> +      - const: syscon
> >> +      - const: isp
> >> +
> >> +  clocks:
> >> +    maxItems: 7
> >> +
> >> +  clock-names:
> >> +    items:
> >> +      - const: apb_func
> >> +      - const: wrapper_clk_c
> >> +      - const: dvp_inv
> >> +      - const: axiwr
> >> +      - const: mipi_rx0_pxl
> >> +      - const: ispcore_2x
> >> +      - const: isp_axi
> >> +
> >> +  resets:
> >> +    maxItems: 6
> >> +
> >> +  reset-names:
> >> +    items:
> >> +      - const: wrapper_p
> >> +      - const: wrapper_c
> >> +      - const: axird
> >> +      - const: axiwr
> >> +      - const: isp_top_n
> >> +      - const: isp_top_axi
> >> +
> >> +  power-domains:
> >> +    items:
> >> +      - description: JH7110 ISP Power Domain Switch Controller.
> >> +
> >> +  interrupts:
> >> +    maxItems: 4
> >> +
> >> +  ports:
> >> +    $ref: /schemas/graph.yaml#/properties/ports
> >> +
> >> +    properties:
> >> +      port@0:
> >> +        $ref: /schemas/graph.yaml#/$defs/port-base
> >> +        unevaluatedProperties: false
> >> +        description: Input port for receiving DVP data.
> >> +
> >> +        properties:
> >> +          endpoint:
> >> +            $ref: video-interfaces.yaml#
> >> +            unevaluatedProperties: false
> >> +
> >> +            properties:
> >> +              bus-width:
> >> +                const: 8
> >> +
> >> +              data-shift:
> >> +                const: 2
> > 
> > As far as I can tell, those two properties are not handled by the
> > driver. I assume this is because the driver doesn't support the DVP
> > input yet. That's fine, but it makes it a bit hard to review the device
> > tree. Could you provide some information about the DVP hardware
> > interface ? Does it support both BT.656 and sync signals, or just sync
> > signals ? Are the polarities of the clock and h/v sync controllable ?
> > Is the parallel input bus 8-bit wide or are other options supported ?
> > And finally, what are you modelling with data-shift: 2 ?
> 
> Hello Laurent,
> 
> The DVP hardware supports BT.656 and sync signals, can control the
> polarities of h/v sync, supports 8/10/12 bit wide, and data-shift: 2 is
> line 9-2.

Thank you for the information. Endpoints for port@0 should then require
bus-type. The hsync-active and vsync-active should be listed with
default values and be optional. bus-width should have 8, 10 and 12 as
supported values, and be required, or have a default (I think making it
required is best). data-shift should list supported values too,
including 0, and be optional with a default of 0.

> >> +
> >> +      port@1:
> >> +        $ref: /schemas/graph.yaml#/properties/port
> >> +        description: Input port for receiving CSI data.
> >> +
> >> +    required:
> >> +      - port@0
> >> +      - port@1
> >> +
> >> +required:
> >> +  - compatible
> >> +  - reg
> >> +  - reg-names
> >> +  - clocks
> >> +  - clock-names
> >> +  - resets
> >> +  - reset-names
> >> +  - power-domains
> >> +  - interrupts
> >> +  - ports
> >> +
> >> +additionalProperties: false
> >> +
> >> +examples:
> >> +  - |
> >> +    isp@19840000 {
> >> +        compatible = "starfive,jh7110-camss";
> >> +        reg = <0x19840000 0x10000>,
> >> +              <0x19870000 0x30000>;
> >> +        reg-names = "syscon", "isp";
> >> +        clocks = <&ispcrg 0>,
> >> +                 <&ispcrg 13>,
> >> +                 <&ispcrg 2>,
> >> +                 <&ispcrg 12>,
> >> +                 <&ispcrg 1>,
> >> +                 <&syscrg 51>,
> >> +                 <&syscrg 52>;
> >> +        clock-names = "apb_func",
> >> +                      "wrapper_clk_c",
> >> +                      "dvp_inv",
> >> +                      "axiwr",
> >> +                      "mipi_rx0_pxl",
> >> +                      "ispcore_2x",
> >> +                      "isp_axi";
> >> +        resets = <&ispcrg 0>,
> >> +                 <&ispcrg 1>,
> >> +                 <&ispcrg 10>,
> >> +                 <&ispcrg 11>,
> >> +                 <&syscrg 41>,
> >> +                 <&syscrg 42>;
> >> +        reset-names = "wrapper_p",
> >> +                      "wrapper_c",
> >> +                      "axird",
> >> +                      "axiwr",
> >> +                      "isp_top_n",
> >> +                      "isp_top_axi";
> >> +        power-domains = <&pwrc 5>;
> >> +        interrupts = <92>, <87>, <88>, <90>;
> >> +
> >> +        ports {
> >> +            #address-cells = <1>;
> >> +            #size-cells = <0>;
> >> +            port@0 {
> >> +                reg = <0>;
> >> +                vin_from_sc2235: endpoint {
> >> +                    remote-endpoint = <&sc2235_to_vin>;
> >> +                    bus-width = <8>;
> >> +                    data-shift = <2>;
> >> +                    hsync-active = <1>;
> >> +                    vsync-active = <0>;
> >> +                    pclk-sample = <1>;
> >> +                };
> >> +            };
> >> +
> >> +            port@1 {
> >> +                reg = <1>;
> >> +                vin_from_csi2rx: endpoint {
> >> +                    remote-endpoint = <&csi2rx_to_vin>;
> >> +                };
> >> +            };
> >> +        };
> >> +    };
> >> diff --git a/MAINTAINERS b/MAINTAINERS
> >> index bbb8b5c0187b..b8c76b0d7eb3 100644
> >> --- a/MAINTAINERS
> >> +++ b/MAINTAINERS
> >> @@ -19909,6 +19909,13 @@ M:	Ion Badulescu <ionut@xxxxxxxxxx>
> >>  S:	Odd Fixes
> >>  F:	drivers/net/ethernet/adaptec/starfire*
> >>  
> >> +STARFIVE CAMERA SUBSYSTEM DRIVER
> >> +M:	Jack Zhu <jack.zhu@xxxxxxxxxxxxxxxx>
> >> +M:	Changhuang Liang <changhuang.liang@xxxxxxxxxxxxxxxx>
> >> +L:	linux-media@xxxxxxxxxxxxxxx
> >> +S:	Maintained
> >> +F:	Documentation/devicetree/bindings/media/starfive,jh7110-camss.yaml
> >> +
> >>  STARFIVE DEVICETREES
> >>  M:	Emil Renner Berthing <kernel@xxxxxxxx>
> >>  S:	Maintained

-- 
Regards,

Laurent Pinchart