RE: [PATCH v2 0/3] Add and enable USB nodes for ExynosAutov920 SoC

Hi Rob,

Thank you for your feedback on the patch series. 

-----Original Message-----
From: Rob Herring <robh@kernel.org>
Sent: 22 January 2026 10:46 PM
To: Pritam Manohar Sutar <redacted>
Cc: alim.akhtar@samsung.com; conor+dt@kernel.org; krzk+dt@kernel.org;
linux-arm-kernel@lists.infradead.org; rosa.pila@samsung.com;
selvarasu.g@samsung.com; linux-samsung-soc@vger.kernel.org;
muhammed.ali@samsung.com; faraz.ata@samsung.com; linux-
kernel@vger.kernel.org; devicetree@vger.kernel.org;
dev.tailor@samsung.com
Subject: Re: [PATCH v2 0/3] Add and enable USB nodes for ExynosAutov920
SoC


On Thu, 22 Jan 2026 18:37:18 +0530, Pritam Manohar Sutar wrote:

quoted

This SoC has 2 USB typeC and 2 typeA ports those are DWC3 DRD
controllers and among them, one single USB3.1 DRD combo phy and three
USB2.0 only phy controllers. This patchset adds and enables USB and
USB-PHY nodes in dts.

PMIC is not implemented yet, we rely on USB LDOs being enabled by the
bootloader and used dummy regulators for now.

To drive vbus for host mode, it needs GPIO pin to enable vbus regulator.
GPIO expander is present in the dts, we used it to enable the
regulator using GPIO.

USB ports are configured as OTG, and default mode is configured as
peripheral. It will be changed based on requirements.

changelog
----------
Changes in v2:
- As v1 was pushed 3 months back, resending this patchset.
- Since dependencies are merged, removed links from coverletter.
  link for v1:
https://lore.kernel.org/linux-devicetree/20251024114845.2395166-1-prit
am.sutar@samsung.com/

Pritam Manohar Sutar (3):
  arm64: dts: exynos: ExynosAutov920: Add USB and USB-phy nodes
  arm64: dts: exynos: ExynosAutov920: Add regulators for the USB
  arm64: dts: exynos: ExynosAutov920: Enable USB nodes

 .../boot/dts/exynos/exynosautov920-sadk.dts   | 160

+++++++++++++++++

quoted

 .../arm64/boot/dts/exynos/exynosautov920.dtsi | 162
++++++++++++++++++
 2 files changed, 322 insertions(+)

--
2.34.1

My bot found new DTB warnings on the .dts files added or changed in this
series.

Some warnings may be from an existing SoC .dtsi. Or perhaps the warnings
are fixed by another series. Ultimately, it is up to the platform maintainer
whether these warnings are acceptable or not. No need to reply unless the
platform maintainer has comments.

If you already ran DT checks and didn't see these error(s), then make sure dt-
schema is up to date:

  pip3 install dtschema --upgrade


This patch series was applied (using b4) to base:
 Base: attempting to guess base-commit...
 Base: tags/next-20260121 (exact match)
 Base: tags/next-20260121 (use --merge-base to override)

If this is not the correct base, please add 'base-commit' tag (or use b4 which
does this automatically)


New warnings running 'make CHECK_DTBS=y for
arch/arm64/boot/dts/exynos/' for 20260122130721.205664-1-
pritam.sutar@samsung.com:

arch/arm64/boot/dts/exynos/exynosautov920-sadk.dtb: usb-phy0 (usb-
nop-xceiv): '#phy-cells' is a required property
	from schema $id: https://protect2.fireeye.com/v1/url?k=91401ba9-
cedb2354-914190e6-000babff317b-0af64cc1fcd35e1a&q=1&e=e0bf9bed-
20f5-431c-9a8f-
ded53e46a366&u=http%3A%2F%2Fdevicetree.org%2Fschemas%2Fusb%2Fu
sb-nop-xceiv.yaml
arch/arm64/boot/dts/exynos/exynosautov920-sadk.dtb: usb-phy1 (usb-
nop-xceiv): '#phy-cells' is a required property
	from schema $id: https://protect2.fireeye.com/v1/url?k=b208eda5-
ed93d558-b20966ea-000babff317b-f6650041a1e910a7&q=1&e=e0bf9bed-
20f5-431c-9a8f-
ded53e46a366&u=http%3A%2F%2Fdevicetree.org%2Fschemas%2Fusb%2Fu
sb-nop-xceiv.yaml
arch/arm64/boot/dts/exynos/exynosautov920-sadk.dtb: usb-phy2 (usb-
nop-xceiv): '#phy-cells' is a required property
	from schema $id: https://protect2.fireeye.com/v1/url?k=ce686cfd-
91f35400-ce69e7b2-000babff317b-ccbf1b3c353ecfc0&q=1&e=e0bf9bed-20f5-
431c-9a8f-
ded53e46a366&u=http%3A%2F%2Fdevicetree.org%2Fschemas%2Fusb%2Fu
sb-nop-xceiv.yaml
arch/arm64/boot/dts/exynos/exynosautov920-sadk.dtb: usb-phy3 (usb-
nop-xceiv): '#phy-cells' is a required property
	from schema $id: https://protect2.fireeye.com/v1/url?k=633aebf3-
3ca1d30e-633b60bc-000babff317b-ef5a169bc853eddb&q=1&e=e0bf9bed-
20f5-431c-9a8f-
ded53e46a366&u=http%3A%2F%2Fdevicetree.org%2Fschemas%2Fusb%2Fu
sb-nop-xceiv.yaml

Apologize for any inconvenience caused by the issues you’ve identified. 
Below, Have outlined the changes, will implement to address the warnings 
and ensure the patch set aligns with the required standards.

Proposed Changes:
1. Will include #phy-cells = <0>; in the USB PHY nodes 
  (usb_phy0, usb_phy1, usb_phy2, and usb_phy3) 
This is a crucial addition to avoid compilation warnings and ensure compatibility.

Example:
usb_phy0: usb-phy0 {    
    compatible = "usb-nop-xceiv";    
    #phy-cells = <0>;    
    vbus-supply = <&usbdrd31_dwc3_vbus>;    
};    

2. The errors were not caught by the make dt_binding_check and make dtbs_check 
  commands 
  make -j ARCH=arm64 dt_binding_check dtbs_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/phy/samsung,usb3-drd-phy.yaml
  make -j ARCH=arm64 dt_binding_check dtbs_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/usb/samsung,exynos-dwc3.yaml

3. Once the above changes are verified and tested, I will incorporate them into the
  next version of the patch set (v3).

Questions:
1. Are the Proposed Changes Correct?
  Please confirm if the inclusion of #phy-cells = <0>; in the USB PHY nodes is the correct 
  fix for the issue. If there are additional changes required, kindly let me know.

2. Why Warnings Were Not Captured During Initial Checks?
  The make dt_binding_check and make dtbs_check commands did not flag the warnings,
  which suggests the schema or bindings might not be comprehensive enough. Could you 
  provide insights or recommendations on how to improve the schema to catch such issues
  in the future?

 
Thank you for your valuable input. I’ll proceed with the changes and provide an updated 
patch set once the fixes are confirmed. Please let me know if there’s anything else I need
to consider or address.

Regards,
Pritam