Re: [PATCH v2 1/9] dt-bindings: misc: Describe TI FPC202 dual port controller

[Rob Herring <robh@xxxxxxxxxx>]

On Mon, Nov 18, 2024 at 11:13:00AM +0100, Romain Gantois wrote:
> The FPC202 dual port controller serves as a low speed signal aggregator for
> common port types, notably SFP. It provides access to I2C and low-speed
> GPIO signals of a downstream device through a single upstream control
> interface.
> 
> Up to two logical I2C addresses can be accessed on each of the FPC202's
> ports. The port controller acts as an I2C translator (ATR). It converts
> addresses of incoming and outgoing I2C transactions. One use case of this
> is accessing two SFP modules at logical address 0x50 from the same upstream
> I2C controller, using two different client aliases.
> 
> Signed-off-by: Romain Gantois <romain.gantois@xxxxxxxxxxx>
> ---
>  .../devicetree/bindings/misc/ti,fpc202.yaml        | 83 ++++++++++++++++++++++
>  MAINTAINERS                                        |  6 ++
>  2 files changed, 89 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/misc/ti,fpc202.yaml b/Documentation/devicetree/bindings/misc/ti,fpc202.yaml
> new file mode 100644
> index 0000000000000000000000000000000000000000..1c7243f0325211d8cea3736cbe777c4318065b12
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/misc/ti,fpc202.yaml
> @@ -0,0 +1,83 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/misc/ti,fpc202.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: TI FPC202 dual port controller with expanded IOs
> +
> +maintainers:
> +  - Romain Gantois <romain.gantois@xxxxxxxxxxx>
> +
> +allOf:
> +  - $ref: /schemas/i2c/i2c-atr.yaml#
> +
> +properties:
> +  compatible:
> +    const: ti,fpc202
> +
> +  reg:
> +    maxItems: 1
> +
> +  gpio-controller: true
> +
> +  "#gpio-cells":
> +    const: 2
> +
> +  enable-gpios:
> +    description:
> +      Specifier for the GPIO connected to the EN pin.
> +    maxItems: 1
> +
> +  '#address-cells':
> +    const: 1
> +
> +  '#size-cells':
> +    const: 0
> +
> +patternProperties:
> +  "^i2c@[0-1]$":
> +    $ref: /schemas/i2c/i2c-controller.yaml
> +    description: Downstream device ports 0 and 1

'reg' is not covered by i2c-controller.yaml, so it needs to be 
documented here. Along with a 'unevaluatedProperties: false'.

> +
> +required:
> +  - compatible
> +  - gpio-controller
> +  - "#gpio-cells"
> +  - reg
> +  - "#address-cells"
> +  - "#size-cells"
> +  - i2c@0
> +  - i2c@1
> +
> +unevaluatedProperties: false
> +
> +examples:
> +  - |
> +    i2c {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        i2c-atr@f {
> +            compatible = "ti,fpc202";
> +            reg = <0xf>;
> +            #address-cells = <1>;
> +            #size-cells = <0>;
> +
> +            gpio-controller;
> +            #gpio-cells = <2>;
> +
> +            i2c@0 {
> +                #address-cells = <1>;
> +                #size-cells = <0>;
> +                reg = <0>;
> +            };
> +
> +            i2c@1 {
> +                #address-cells = <1>;
> +                #size-cells = <0>;
> +                reg = <1>;
> +            };
> +        };
> +    };
> +...
> diff --git a/MAINTAINERS b/MAINTAINERS
> index b878ddc99f94e7f6e8fa2c479c5a3f846c514730..8e702cefd2070790330eebf6d2a2b592cadb682d 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -23181,6 +23181,12 @@ F:	drivers/misc/tifm*
>  F:	drivers/mmc/host/tifm_sd.c
>  F:	include/linux/tifm.h
>  
> +TI FPC202 DUAL PORT CONTROLLER
> +M:	Romain Gantois <romain.gantois@xxxxxxxxxxx>
> +L:	linux-kernel@xxxxxxxxxxxxxxx
> +S:	Maintained
> +F:	Documentation/devicetree/bindings/misc/ti,fpc202.yaml
> +
>  TI FPD-LINK DRIVERS
>  M:	Tomi Valkeinen <tomi.valkeinen@xxxxxxxxxxxxxxxx>
>  L:	linux-media@xxxxxxxxxxxxxxx
> 
> -- 
> 2.47.0
>