Re: [PATCH v3 2/4] dt-bindings: phy: Add documentation for Airoha AN7581 USB PHY

From: Rob Herring <robh@kernel.org>
To: Christian Marangi <ansuelsmth@gmail.com>
Cc: Conor Dooley <conor@kernel.org>, Vinod Koul <vkoul@kernel.org>,
	Kishon Vijay Abraham I <kishon@kernel.org>,
	Krzysztof Kozlowski <krzk+dt@kernel.org>,
	Conor Dooley <conor+dt@kernel.org>,
	Lorenzo Bianconi <lorenzo@kernel.org>,
	linux-arm-kernel@lists.infradead.org,
	linux-phy@lists.infradead.org, devicetree@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3 2/4] dt-bindings: phy: Add documentation for Airoha AN7581 USB PHY
Date: Thu, 30 Oct 2025 13:51:22 -0500	[thread overview]
Message-ID: <20251030185122.GA236742-robh@kernel.org> (raw)
In-Reply-To: <690266d4.050a0220.3a144c.eef7@mx.google.com>

On Wed, Oct 29, 2025 at 08:11:10PM +0100, Christian Marangi wrote:
> On Wed, Oct 29, 2025 at 06:35:51PM +0000, Conor Dooley wrote:
> > On Wed, Oct 29, 2025 at 07:24:04PM +0100, Christian Marangi wrote:
> > > On Wed, Oct 29, 2025 at 06:07:22PM +0000, Conor Dooley wrote:
> > > > On Wed, Oct 29, 2025 at 06:37:10PM +0100, Christian Marangi wrote:
> > > > > Add documentation for Airoha AN7581 USB PHY that describe the USB PHY
> > > > > for the USB controller.
> > > > > 
> > > > > Airoha AN7581 SoC support a maximum of 2 USB port. The USB 2.0 mode is
> > > > > always supported. The USB 3.0 mode is optional and depends on the Serdes
> > > > > mode currently configured on the system for the relevant USB port.
> > > > > 
> > > > > The first USB port on the SoC can be both used for USB 3.0 operation or
> > > > > Ethernet (HSGMII).
> > > > > The second USB port on the SoC can be both used for USB 3.0 operation or
> > > > > for an additional PCIe line.
> > > > > 
> > > > > Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
> > > > > ---


> > > > > +  '#phy-cells':
> > > > > +    description: Describe if the referred PHY is the USB 2.0 PHY or USB 3.0 PHY.
> > > > > +    const: 1
> > > > 
> > > > Which is which here?
> > > >
> > > 
> > > Mhh I think I didn't understand here. #phy-cells describe the
> > > parameters to be used for phys property in a different node.
> > > 
> > > The current usage would be
> > > 
> > > <&usb0_phy PHY_TYPE_USB2> for USB 2.0
> > > or <&usb0_phy PHY_TYPE_USB3> for USB 3.0
> > > 
> > > This node expose 2 PHY that can be referenced by the single parameters.
> > 
> > Ah, I didn't know that the 1 cell variant here was type not index.
> > 
> 
> Yes in the driver I'm maching for type not index as it's very confusing.
> Any hint on better describe it on the schema? Maybe I can reword with
> 
> "Describe if the referred PHY is PHY_TYPE_USB2 or PHY_TYPE_USB3"

"The cell contains the mode, PHY_TYPE_USB2 or PHY_TYPE_USB3, as defined 
in dt-bindings/phy/phy.h."

Rob