Re: [PATCH v6 3/7] dt-bindings: i3c: Add NXP P3H2x4x i3c-hub support

Krzysztof Kozlowski
2026-03-11T06:13:58Z

On Tue, Mar 10, 2026 at 12:27:23PM +0530, Lakshay Piplani wrote:
> From: Aman Kumar Pandey <aman.kumarpandey@nxp.com>
>
> Add bindings for the NXP P3H2x4x (P3H2440/P3H2441/P3H2840/P3H2841)
> multiport I3C hub family. These devices connect to a host via
> I3C/I2C/SMBus and allow communication with multiple downstream
> peripherals.
>
> Signed-off-by: Aman Kumar Pandey <aman.kumarpandey@nxp.com>
> Signed-off-by: Vikash Bansal <vikash.bansal@nxp.com>
>
> ---
> Changes in v6:
> - Use a vendor prefix for the attributes

Where is cover letter with links to previous versions?

>
> Changes in v5:
> - Removed SW properties: cp0-ldo-microvolt,cp1-ldo-microvolt,
> tp0145-ldo-microvolt, tp2367-ldo-microvolt
> - Changed supply entries and its descriptions
>
> Changes in v4:
> - Fixed DT binding check warning
> - Removed SW properties: ibi-enable, local-dev, and always-enable
>
> Changes in v3:
> - Added MFD (Multi-Function Device) support for I3C hub and on-die regulator
> - Added Regulator supply node
>
> Changes in v2:
> - Fixed DT binding check warning
> - Revised logic for parsing DTS nodes
> ---
> ---
> .../devicetree/bindings/i3c/nxp,p3h2840.yaml | 209 ++++++++++++++++++
> MAINTAINERS | 8 +
> 2 files changed, 217 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/i3c/nxp,p3h2840.yaml
>
> diff --git a/Documentation/devicetree/bindings/i3c/nxp,p3h2840.yaml b/Documentation/devicetree/bindings/i3c/nxp,p3h2840.yaml
> new file mode 100644
> index 000000000000..e592952e8164
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/i3c/nxp,p3h2840.yaml
> @@ -0,0 +1,209 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +# Copyright 2025 NXP
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/i3c/nxp,p3h2840.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: NXP P3H2X4X I3C HUB
> +
> +maintainers:
> + - Aman Kumar Pandey <aman.kumarpandey@nxp.com>
> + - Vikash Bansal <vikash.bansal@nxp.com>
> +
> +description: |
> + P3H2x4x (P3H2440/P3H2441/P3H2840/P3H2841) is a family of multiport I3C
> + hub devices that connect to:-
> + 1. A host CPU via I3C/I2C/SMBus bus on upstream side and connect to multiple
> + peripheral devices on the downstream side.
> + 2. Have two Controller Ports which can support either
> + I2C/SMBus or I3C buses and connect to a CPU, BMC or SOC.
> + 3. P3H2840/ P3H2841 are 8 port I3C hub with eight I3C/I2C Target Port.
> + 4. P3H2440/ P3H2441 are 4 port I3C hub with four I3C/I2C Target Port.
> + Target ports can be configured as I2C/SMBus, I3C or GPIO and connect to
> + peripherals.
> +
> +allOf:
> + - $ref: /schemas/i3c/i3c.yaml#
> +
> +properties:
> + compatible:
> + const: nxp,p3h2840
> +
> + nxp,tp0145-pullup-ohms:
> + description:
> + Selects the pull up resistance for target Port 0/1/4/5, in ohms.
> + enum: [250, 500, 1000, 2000]
> + default: 500
> +
> + nxp,tp2367-pullup-ohms:
> + description:
> + Selects the pull up resistance for target Port 2/3/6/7, in ohms.
> + enum: [250, 500, 1000, 2000]
> + default: 500
> +
> + nxp,cp0-io-strength-ohms:
> + description:
> + Selects the IO drive strength for controller Port 0, in ohms.
> + enum: [20, 30, 40, 50]
> + default: 20
> +
> + nxp,cp1-io-strength-ohms:
> + description:
> + Selects the IO drive strength for controller Port 1, in ohms.
> + enum: [20, 30, 40, 50]
> + default: 20
> +
> + nxp,tp0145-io-strength-ohms:
> + description:
> + Selects the IO drive strength for target port 0/1/4/5, in ohms.
> + enum: [20, 30, 40, 50]
> + default: 20
> +
> + nxp,tp2367-io-strength-ohms:
> + description:
> + Selects the IO drive strength for target port 2/3/6/7, in ohms.
> + enum: [20, 30, 40, 50]
> + default: 20
> +
> + vcc1-supply:
> + description: Controller port 0 power supply.
> +
> + vcc2-supply:
> + description: Controller port 1 power supply.
> +
> + vcc3-supply:
> + description: Target port 0/1/4/5 power supply.
> +
> + vcc4-supply:
> + description: Target port 2/3/6/7 power supply.
> +
> + regulators:
> + type: object
> + additionalProperties: false
> +
> + properties:
> + ldo-cp0:
> + type: object
> + $ref: /schemas/regulator/regulator.yaml#
> + unevaluatedProperties: false
> +
> + ldo-cp1:
> + type: object
> + $ref: /schemas/regulator/regulator.yaml#
> + unevaluatedProperties: false
> +
> + ldo-tpg0:
> + type: object
> + $ref: /schemas/regulator/regulator.yaml#
> + unevaluatedProperties: false
> +
> + ldo-tpg1:
> + type: object
> + $ref: /schemas/regulator/regulator.yaml#
> + unevaluatedProperties: false
> +
> +patternProperties:
> + "^i3c@[0-7]$":
> + type: object
> + $ref: /schemas/i3c/i3c.yaml#
> + unevaluatedProperties: false
> +
> + properties:
> + reg:
> + description:
> + The I3C HUB Target Port number.
> + maximum: 7
> +
> + nxp,pullup-enable:
> + type: boolean
> + description:
> + Enables the on-die pull-up for Target Port.
> +
> + "^(i2c|smbus)@[0-7]$":
> + type: object
> + $ref: /schemas/i2c/i2c-controller.yaml#
> + unevaluatedProperties: false
> +
> + properties:
> + reg:
> + description:
> + The I3C HUB Target Port number.
> + maximum: 7
> +
> + nxp,pullup-enable:
> + type: boolean
> + description:
> + Enables the on-die pull-up for Target Port.
> +
> +unevaluatedProperties: false
> +
> +examples:
> + - |
> + i3c {
> + #address-cells = <3>;
> + #size-cells = <0>;
> +
> + hub@70,236153000c2 {
> + reg = <0x70 0x236 0x3000c2>;

Where is the compatible?

So this wasn't checked/tested. Try yourself, remove required properties
and see if there is an error. No error, right?

Best regards,
Krzysztof