RE: [PATCH net-next 1/5] dt-bindings: net: add onsemi's TS2500/NCN26010 10BASE-T1S MACPHY

[Selvamani Rajagopal]

> -----Original Message-----
> From: Rob Herring <robh@xxxxxxxxxx>
> Sent: Tuesday, May 5, 2026 6:45 AM
> To: Selvamani Rajagopal <Selvamani.Rajagopal@xxxxxxxxxx>
> Cc: Piergiorgio Beruto <Pier.Beruto@xxxxxxxxxx>; andrew+netdev@xxxxxxx;
> davem@xxxxxxxxxxxxx; edumazet@xxxxxxxxxx; kuba@xxxxxxxxxx; pabeni@xxxxxxxxxx;
> krzk+dt@xxxxxxxxxx; conor+dt@xxxxxxxxxx; netdev@xxxxxxxxxxxxxxx;
> devicetree@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH net-next 1/5] dt-bindings: net: add onsemi's TS2500/NCN26010
> 10BASE-T1S MACPHY
> 
> 
> This Message Is From an External Sender
> This message came from outside your organization.
> 
> On Fri, May 01, 2026 at 07:15:17PM +0000, Selvamani Rajagopal wrote:
> > Add YAML device tree binding for the onsemi NCN26010 and TS2500
> > IEEE 802.3cg compliant Ethernet transceiver devices.
> >
> > Signed-off-by: Selvamani Rajagopal <Selvamani.Rajagopal@xxxxxxxxxx>
> > ---
> > .../bindings/net/onnn,ncn260xx.yaml | 71 +++++++++++++++++++
> > 1 file changed, 71 insertions(+)
> > create mode 100644 Documentation/devicetree/bindings/net/onnn,ncn260xx.yaml
> >
> > diff --git a/Documentation/devicetree/bindings/net/onnn,ncn260xx.yaml
> b/Documentation/devicetree/bindings/net/onnn,ncn260xx.yaml
> > new file mode 100644
> > index 000000000..198cd7e9d
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/net/onnn,ncn260xx.yaml
> > @@ -0,0 +1,71 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/net/onnn,ncn260xx.yaml#
> <http://devicetree.org/schemas/net/onnn,ncn260xx.yaml#
> vicetree.org>
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> <http://devicetree.org/meta-schemas/core.yaml#
> n=devicetree.org>
> > +
> > +title: onsemi NCN26010/TS2500 10BASE-T1S MACPHY Ethernet Controllers
> > +
> > +maintainers:
> > + - Piergiorgio Beruto <Pier.Beruto@xxxxxxxxxx>
> > + - Selva Rajagopal <Selvamani.Rajagopal@xxxxxxxxxx>
> > +
> > +description: |
> > + The NCN26010 and TS2500 combine a Media Access Controller (MAC) and an
> > + Ethernet PHY to enable 10BASE‑T1S networks. The Ethernet Media Access
> > + Controller (MAC) module implements a 10 Mbps half duplex Ethernet MAC,
> > + compatible with the IEEE 802.3 standard and a 10BASE-T1S physical layer
> > + transceiver integrated into the NCN26010. The communication between
> > + the host and the MAC-PHY is specified in the OPEN Alliance 10BASE-T1x
> > + MACPHY Serial Interface (TC6).
> > +
> > + Specifications about the NCN26010 can be found at:
> > + https://www.onsemi.com/download/data-sheet/pdf/ncn26010-d.pdf
> <https://www.onsemi.com/download/data-sheet/pdf/ncn26010-d.pdf
> n=onsemi.com>
> > + https://www.onsemi.com/products/interfaces/ethernet-controllers/t30hm1ts2500
> <https://www.onsemi.com/products/interfaces/ethernet-controllers/t30hm1ts2500
> semi.com>
> > +
> > +allOf:
> > + - $ref: /schemas/net/ethernet-controller.yaml#
> > + - $ref: /schemas/spi/spi-peripheral-props.yaml#
> > +
> > +properties:
> > + compatible:
> > + const: onnn,ncn260xx
> 
> Don't use wildcards in compatible strings.
> 
> > +
> > + reg:
> > + maxItems: 1
> > +
> > + interrupts:
> > + description: |
> 
> Don't need '|'.
> 
> > + Interrupt from MAC-PHY asserted in the event of Receive Chunks
> > + Available, Transmit Chunk Credits Available and Extended Status
> > + Event.
> > + maxItems: 1
> > +
> > + spi-max-frequency:
> > + minimum: 15000000
> 
> A minimum is strange. What if you have a board issue requiring lower
> frequency?

Had the same question in internal review. Datasheet says the minimum speed 15 MHz is needed. That's why we had placed.

> 
> > + maximum: 25000000
> > +
> > +required:
> > + - compatible
> > + - reg
> > + - interrupts
> > + - spi-max-frequency
> 
> Normally this is not required. It's only for boards which can't operate
> at the maximum frequency of the device.
> 
> > +
> > +additionalProperties: false
> > +
> > +examples:
> > + - |
> > + spi {
> > + #address-cells = <1>;
> > + #size-cells = <0>;
> > +
> > + ethernet@0 {
> > + compatible = "onnn,ncn260xx";
> > + reg = <0>;
> > + pinctrl-names = "default";
> > + interrupt-parent = <&gpio>;
> > + interrupts = <25 2>;
> > + status = "okay";
> 
> Drop. Examples are always enabled.
> 
> > + spi-max-frequency = <25000000>;
> > + };
> > + };
> > --
> > 2.43.0
> >
> >
> > Public Information