RE: [PATCH v7 5/6] dt-bindings: phy: samsung,usb3-drd-phy: add ExynosAutov920 combo ssphy

["Pritam Manohar Sutar" <pritam.sutar@samsung.com>]

Hi Krzysztof, 

> -----Original Message-----
> From: Krzysztof Kozlowski <krzk@kernel.org>
> Sent: 24 August 2025 02:26 PM
> To: Pritam Manohar Sutar <pritam.sutar@samsung.com>
> Cc: vkoul@kernel.org; kishon@kernel.org; robh@kernel.org;
> krzk+dt@kernel.org; conor+dt@kernel.org; alim.akhtar@samsung.com;
> andre.draszik@linaro.org; peter.griffin@linaro.org; kauschluss@disroot.org;
> ivo.ivanov.ivanov1@gmail.com; igor.belwon@mentallysanemainliners.org;
> johan@kernel.org; m.szyprowski@samsung.com; s.nawrocki@samsung.com;
> linux-phy@lists.infradead.org; devicetree@vger.kernel.org; linux-
> kernel@vger.kernel.org; linux-arm-kernel@lists.infradead.org; linux-samsung-
> soc@vger.kernel.org; rosa.pila@samsung.com; dev.tailor@samsung.com;
> faraz.ata@samsung.com; muhammed.ali@samsung.com;
> selvarasu.g@samsung.com
> Subject: Re: [PATCH v7 5/6] dt-bindings: phy: samsung,usb3-drd-phy: add
> ExynosAutov920 combo ssphy
> 
> On Fri, Aug 22, 2025 at 03:08:44PM +0530, Pritam Manohar Sutar wrote:
> > This phy supports USB3.1 SSP+(10Gbps) protocol and is backwards
> > compatible to the USB3.0 SS(5Gbps). It requires two clocks, named
> > "phy" and "ref". The required supplies for USB3.1 are named as
> > vdd075_usb30(0.75v), vdd18_usb30(1.8v).
> 
> Please do not describe the schema, but hardware. This sentence does not help
> me in my question further.

This is a combo phy having Synopsys usb20 and usb30 phys (these 2 phys are totally different). 
One PHY only supports usb2.0 and data rates whereas another one does usb3.1 ssp+ and usb3.1 ssp
	
This patch only explains about usb30 (since these are two different phys) phy and omitted inclusion of usb20 reference (added separate patch for this patch no 3). 
	
Hope this is clear.

> 
> >
> > Add schemas for combo ssphy found on this SoC.
> >
> > Signed-off-by: Pritam Manohar Sutar <pritam.sutar@samsung.com>
> > ---
> >  .../bindings/phy/samsung,usb3-drd-phy.yaml    | 23 +++++++++++++++++++
> >  1 file changed, 23 insertions(+)
> >
> > diff --git
> > a/Documentation/devicetree/bindings/phy/samsung,usb3-drd-phy.yaml
> > b/Documentation/devicetree/bindings/phy/samsung,usb3-drd-phy.yaml
> > index f0cfca5736b8..96e5bbb2e42c 100644
> > --- a/Documentation/devicetree/bindings/phy/samsung,usb3-drd-phy.yaml
> > +++ b/Documentation/devicetree/bindings/phy/samsung,usb3-drd-phy.yaml
> > @@ -34,6 +34,7 @@ properties:
> >        - samsung,exynos7870-usbdrd-phy
> >        - samsung,exynos850-usbdrd-phy
> >        - samsung,exynos990-usbdrd-phy
> > +      - samsung,exynosautov920-usb31drd-combo-ssphy
> >        - samsung,exynosautov920-usbdrd-combo-hsphy
> >        - samsung,exynosautov920-usbdrd-phy
> >
> > @@ -118,6 +119,12 @@ properties:
> >    vdd18-usb20-supply:
> >      description: 1.8V power supply for the USB 2.0 phy.
> >
> > +  dvdd075-usb30-supply:
> > +    description: 0.75V power supply for the USB 3.0 phy.
> > +
> > +  vdd18-usb30-supply:
> > +    description: 1.8V power supply for the USB 3.0 phy.
> > +
> >  required:
> >    - compatible
> >    - clocks
> > @@ -227,6 +234,7 @@ allOf:
> >                - samsung,exynos7870-usbdrd-phy
> >                - samsung,exynos850-usbdrd-phy
> >                - samsung,exynos990-usbdrd-phy
> > +              - samsung,exynosautov920-usb31drd-combo-ssphy
> >                - samsung,exynosautov920-usbdrd-combo-hsphy
> >                - samsung,exynosautov920-usbdrd-phy
> >      then:
> > @@ -262,6 +270,21 @@ allOf:
> >        properties:
> >          dvdd075-usb20-supply: false
> >          vdd18-usb20-supply: false
> > +  - if:
> > +      properties:
> > +        compatible:
> > +          contains:
> > +            enum:
> > +              - samsung,exynosautov920-usb31drd-combo-ssphy
> > +    then:
> > +      required:
> > +        - dvdd075-usb30-supply
> > +        - vdd18-usb30-supply
> 
> Why are you adding usb20 and usb30 suffixes to the supplies? These are
> separate devices, so they do not have both variants at the same time.

This is a combo phy consisting of usb2 and usb3 phys combined. 
To drive these separate phys, added suffixes for these supplies respectively.

Moreover, gs101 is also using similar convention for its usb20 and dp supplies. 
Added suffix for usb2 and usb3 as per our last communication https://lore.kernel.org/linux-phy/6e1c67d2-9bfa-442a-9d53-8c5970a2a9ef@kernel.org/

> 
> From this device point of view, the supply is called dvdd075 or vdd18.
> If you open device datasheet (not SoC datasheet), that's how it will be called,
> most likely.

Yes, Agree. In device datasheet, suffixes are not mentioned, but in our board schematic it is mentioned. 
Let me know your suggestion about adding suffixes?

> 
> Best regards,
> Krzysztof


Thank you.

Regards,
Pritam