Re: [PATCH v7 14/24] dt-bindings: media: i2c: add MAX9296A, MAX96716A, MAX96792A

[Sakari Ailus <sakari.ailus@linux.intel.com>]

Hi Cosmin,

On Fri, Jul 18, 2025 at 06:24:50PM +0300, Cosmin Tanislav wrote:
> The MAX9296A deserializer converts single or dual serial inputs to MIPI
> CSI-2 outputs. The GMSL2 links operate at a fixed rate of 3Gbps or 6Gbps
> in the forward direction and 187.5Mbps in the reverse direction.
> In GMSL1 mode, each serial link can be paired with 3.12Gbps or 1.5Gbps
> GMSL1 serializers or operate up to 4.5Gbps with GMSL2 serializers with
> GMSL1 backward compatibility. The MAX9296A supports mixed GMSL2 and
> GMSL1 links. The serial inputs operate independently, allowing videos
> with different timings and resolutions to be received on each input.

C-PHY or D-PHY? I'd assume the latter?

> 
> MAX96716A supports both tunnel and pixel mode.
> MAX96792A supports both tunnel and pixel mode, and has two GMSL3 links.
> 
> Signed-off-by: Cosmin Tanislav <demonsingur@gmail.com>
> Acked-by: Rob Herring (Arm) <robh@kernel.org>
> ---
>  .../bindings/media/i2c/maxim,max9296a.yaml    | 242 ++++++++++++++++++
>  MAINTAINERS                                   |   6 +
>  2 files changed, 248 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/media/i2c/maxim,max9296a.yaml
> 
> diff --git a/Documentation/devicetree/bindings/media/i2c/maxim,max9296a.yaml b/Documentation/devicetree/bindings/media/i2c/maxim,max9296a.yaml
> new file mode 100644
> index 0000000000000..4f2b3b5b69cf4
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/media/i2c/maxim,max9296a.yaml
> @@ -0,0 +1,242 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +# Copyright (C) 2024 Collabora Ltd.
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/media/i2c/maxim,max9296a.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Maxim MAX9296A GMSL2 to CSI-2 Deserializer
> +
> +maintainers:
> +  - Cosmin Tanislav <cosmin.tanislav@analog.com>
> +
> +description: >
> +  The MAX9296A deserializer converts single or dual serial inputs to
> +  MIPI CSI-2 outputs. The GMSL2 links operate at a fixed rate of 3Gbps
> +  or 6Gbps in the forward direction and 187.5Mbps in the reverse
> +  direction. In GMSL1 mode, each serial link can be paired with 3.12Gbps
> +  or 1.5Gbps GMSL1 serializers or operate up to 4.5Gbps with GMSL2
> +  serializers with GMSL1 backward compatibility. The MAX9296A supports
> +  mixed GMSL2 and GMSL1 links. The serial inputs operate independently,
> +  allowing videos with different timings and resolutions to be received
> +  on each input.
> +
> +  MAX96716A supports both tunnel and pixel mode.
> +
> +  MAX96792A supports both tunnel and pixel mode, and has two GMSL3 links.
> +
> +properties:
> +  compatible:
> +    enum:
> +      - maxim,max9296a
> +      - maxim,max96716a
> +      - maxim,max96792a
> +
> +  reg:
> +    maxItems: 1
> +
> +  powerdown-gpios:
> +    maxItems: 1
> +    description: Specifier for the GPIO connected to the PWDNB pin.
> +
> +  port0-poc-supply:
> +    description: Regulator providing Power over Coax for GMSL port 0
> +
> +  port1-poc-supply:
> +    description: Regulator providing Power over Coax for GMSL port 1
> +
> +  i2c-alias-pool:
> +    maxItems: 2
> +
> +  i2c-atr:
> +    type: object
> +    additionalProperties: false
> +
> +    properties:
> +      '#address-cells':
> +        const: 1
> +
> +      '#size-cells':
> +        const: 0
> +
> +    patternProperties:
> +      '^i2c@[0-1]$':
> +        $ref: /schemas/i2c/i2c-controller.yaml#
> +        unevaluatedProperties: false
> +        properties:
> +          reg:
> +            items:
> +              minimum: 0
> +              maximum: 1
> +
> +  ports:
> +    $ref: /schemas/graph.yaml#/properties/ports
> +
> +    patternProperties:
> +      '^port@[0-1]$':
> +        $ref: /schemas/graph.yaml#/properties/port
> +        description: GMSL Input ports 0-1
> +
> +      '^port@[2-3]$':
> +        $ref: /schemas/graph.yaml#/$defs/port-base
> +        unevaluatedProperties: false
> +        description: CSI-2 Output ports 0-1
> +        properties:
> +          endpoint:
> +            $ref: /schemas/media/video-interfaces.yaml#
> +            unevaluatedProperties: false
> +
> +            properties:
> +              data-lanes:
> +                minItems: 1
> +                maxItems: 4
> +
> +              lane-polarities:
> +                minItems: 1

With D-PHY, 2 is the minimum.

> +                maxItems: 5
> +
> +              link-frequencies:
> +                maxItems: 1
> +
> +            required:
> +              - data-lanes
> +
> +    anyOf:
> +      - required:
> +          - port@2
> +      - required:
> +          - port@3
> +
> +required:
> +  - compatible
> +  - reg
> +  - ports
> +
> +additionalProperties: false
> +
> +allOf:
> +  - $ref: /schemas/i2c/i2c-atr.yaml#
> +
> +dependentRequired:
> +  i2c-atr: [i2c-alias-pool]
> +  i2c-alias-pool: [i2c-atr]
> +
> +examples:
> +  - |
> +    #include <dt-bindings/gpio/gpio.h>
> +    #include <dt-bindings/media/video-interfaces.h>
> +
> +    i2c {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        deserializer@28 {
> +            compatible = "maxim,max9296a";
> +            reg = <0x28>;
> +            powerdown-gpios = <&main_gpio0 37 GPIO_ACTIVE_LOW>;
> +
> +            i2c-alias-pool = <0x40 0x41>;
> +
> +            ports {
> +                #address-cells = <1>;
> +                #size-cells = <0>;
> +
> +                port@0 {
> +                    reg = <0>;
> +                    des_gmsl_in_0: endpoint {
> +                        remote-endpoint = <&ser_0_gmsl_out>;
> +                    };
> +                };
> +
> +                port@1 {
> +                    reg = <1>;
> +                    des_gmsl_in_1: endpoint {
> +                        remote-endpoint = <&ser_1_gmsl_out>;
> +                    };
> +                };
> +
> +                port@2 {
> +                    reg = <2>;
> +                    des_csi_out: endpoint {
> +                        data-lanes = <1 2 3 4>;
> +                        link-frequencies = /bits/ 64 <400000000>;
> +                        remote-endpoint = <&csi_in>;
> +                    };
> +                };
> +            };
> +
> +            i2c-atr {
> +                #address-cells = <1>;
> +                #size-cells = <0>;
> +
> +                i2c@0 {
> +                    #address-cells = <1>;
> +                    #size-cells = <0>;
> +                    reg = <0>;
> +
> +                    serializer@40 {
> +                        compatible = "maxim,max96717", "maxim,max96717f";
> +                        reg = <0x40>;
> +                        gpio-controller;
> +                        #gpio-cells = <2>;
> +                        #clock-cells = <0>;
> +
> +                        ports {
> +                            #address-cells = <1>;
> +                            #size-cells = <0>;
> +
> +                            port@0 {
> +                                reg = <0>;
> +                                ser_0_csi_in: endpoint {
> +                                    data-lanes = <1 2>;
> +                                    remote-endpoint = <&sensor_0_out>;
> +                                };
> +                            };
> +
> +                            port@1 {
> +                                reg = <1>;
> +                                ser_0_gmsl_out: endpoint {
> +                                    remote-endpoint = <&des_gmsl_in_0>;
> +                                };
> +                            };
> +                        };
> +                    };
> +                };
> +
> +                i2c@1 {
> +                    #address-cells = <1>;
> +                    #size-cells = <0>;
> +                    reg = <1>;
> +
> +                    serializer@40 {
> +                        compatible = "maxim,max96717", "maxim,max96717f";
> +                        reg = <0x40>;
> +                        gpio-controller;
> +                        #gpio-cells = <2>;
> +                        #clock-cells = <0>;
> +
> +                        ports {
> +                            #address-cells = <1>;
> +                            #size-cells = <0>;
> +
> +                            port@0 {
> +                                reg = <0>;
> +                                ser_1_csi_in: endpoint {
> +                                    data-lanes = <1 2>;
> +                                    remote-endpoint = <&sensor_1_out>;
> +                                };
> +                            };
> +
> +                            port@1 {
> +                                reg = <1>;
> +                                ser_1_gmsl_out: endpoint {
> +                                    remote-endpoint = <&des_gmsl_in_1>;
> +                                };
> +                            };
> +                        };
> +                    };
> +                };
> +            };
> +        };
> +    };
> +...
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 93e22dfd61c17..0eb1729ae1647 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -14783,6 +14783,12 @@ S:	Maintained
>  F:	Documentation/devicetree/bindings/iio/proximity/maxbotix,mb1232.yaml
>  F:	drivers/iio/proximity/mb1232.c
>  
> +MAXIM GMSL2/3 SERIALIZERS AND DESERIALIZERS
> +M:	Cosmin Tanislav <cosmin.tanislav@analog.com>
> +L:	linux-media@vger.kernel.org
> +S:	Maintained
> +F:	Documentation/devicetree/bindings/media/i2c/maxim,max9296a.yaml
> +
>  MAXIM MAX11205 DRIVER
>  M:	Ramona Bolboaca <ramona.bolboaca@analog.com>
>  L:	linux-iio@vger.kernel.org

-- 
Kind regards,

Sakari Ailus