Re: [RFC PATCH v2 11/16] dt-bindings: media: i2c: add MAX9296A, MAX96716A, MAX96792A

Cosmin Tanislav
2025-03-11T22:26:24Z

On 3/11/25 9:07 PM, Rob Herring wrote:
> On Sun, Mar 09, 2025 at 10:48:03AM +0200, 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.
>>
>> 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>
>> ---
>> .../bindings/media/i2c/maxim,max9296a.yaml | 281 ++++++++++++++++++
>> MAINTAINERS | 6 +
>> 2 files changed, 287 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 000000000000..97731549d161
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/media/i2c/maxim,max9296a.yaml
>> @@ -0,0 +1,281 @@
>> +# 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:
>
> Needs '>' token as you have paragraphs.
>
>> + 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-mux:
>> + $ref: /schemas/i2c/i2c-mux.yaml#
>> + unevaluatedProperties: false
>> + patternProperties:
>> + '^i2c@[0-1]$':
>> + $ref: /schemas/i2c/i2c-controller.yaml#
>> + unevaluatedProperties: false
>> + properties:
>> + reg:
>> + items:
>> + minimum: 0
>> + maximum: 1
>> +
>> + i2c-alias-pool:
>> + maxItems: 2
>> +
>> + i2c-atr:
>> + type: object
>> + additionalProperties: false
>> +
>> + properties:
>> + '#address-cells':
>> + const: 1
>> +
>> + '#size-cells':
>> + const: 0
>> +
>> + patternProperties:
>> + '^i2c@[0-1]$':
>> + $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
>> + unevaluatedProperties: false
>> + description: GMSL Input
>> + properties:
>> + endpoint:
>> + $ref: /schemas/media/video-interfaces.yaml#
>
> What properties are you using from here?
>
> None actually because /schemas/graph.yaml#/properties/port won't allow
> any.
>

So these lines should be removed.

unevaluatedProperties: false
properties:
endpoint:
$ref: /schemas/media/video-interfaces.yaml#
unevaluatedProperties: false
description:
Endpoint for GMSL2-Link port.

Should I submit patches to do the same for the maxim,max96714.yaml file?

I basically copied these bindings from there and adapted them, and those
bindings seem to have the same issue.

>
>> + unevaluatedProperties: false
>> + description: Endpoint for GMSL2-Link port.
>> +
>> + '^port@[2-3]$':
>> + $ref: /schemas/graph.yaml#/$defs/port-base
>> + unevaluatedProperties: false
>> + description: CSI-2 Output port
>> + properties:
>> + endpoint:
>> + $ref: /schemas/media/video-interfaces.yaml#
>> + unevaluatedProperties: false
>> +
>> + properties:
>> + data-lanes:
>> + minItems: 1
>> + maxItems: 4
>> +
>> + lane-polarities:
>> + minItems: 1
>> + 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#
>> +
>> + - if:
>> + properties:
>> + compatible:
>> + contains:
>> + enum:
>> + - maxim,max9296a
>> + - maxim,max96792a
>> + then:
>> + not:
>> + required: [i2c-mux]
>> +
>> + - if:
>> + properties:
>> + compatible:
>> + contains:
>> + enum:
>> + - maxim,max96716a
>> + then:
>> + not:
>> + required: [i2c-atr]
>> +
>> +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";
>> + 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";
>> + 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 abf3afc95fc9..c1e01668e81a 100644
>> --- a/MAINTAINERS
>> +++ b/MAINTAINERS
>> @@ -14220,6 +14220,12 @@ S: Maintained
>> F: Documentation/devicetree/bindings/iio/proximity/maxbotix,mb1232.yaml
>> F: drivers/iio/proximity/mb1232.c
>>
>> +MAXIM GMSL2 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
>> --
>> 2.48.1
>>