Re: [PATCH v4 1/4] dt-bindings: net: Add Realtek MDIO controller
From: Krzysztof Kozlowski <krzk@kernel.org>
Date: 2025-01-22 08:12:13
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On Mon, Jan 20, 2025 at 05:02:11PM +1300, Chris Packham wrote:
quoted hunk ↗ jump to hunk
Add dtschema for the MDIO controller found in the RTL9300 SoCs. The controller is slightly unusual in that direct MDIO communication is not possible. We model the MDIO controller with the MDIO buses as child nodes and the PHYs as children of the buses. Because we do need the switch port number to actually communicate over the MDIO bus this needs to be supplied via the "realtek,port" property. Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz> --- Notes: Changes in v4: - Model the MDIO controller with the buses as child nodes. We still need to deal with the switch port number so this is represented with the "realtek,port" property which needs to be added to the MDIO bus children (i.e. the PHYs) - Because the above is quite a departure from earlier I've dropped the r-by Changes in v3: - Add r-by from Connor Changes in v2: - None .../bindings/net/realtek,rtl9301-mdio.yaml | 93 +++++++++++++++++++ 1 file changed, 93 insertions(+) create mode 100644 Documentation/devicetree/bindings/net/realtek,rtl9301-mdio.yamldiff --git a/Documentation/devicetree/bindings/net/realtek,rtl9301-mdio.yaml b/Documentation/devicetree/bindings/net/realtek,rtl9301-mdio.yaml new file mode 100644 index 000000000000..e3ecb1b4afd3 --- /dev/null +++ b/Documentation/devicetree/bindings/net/realtek,rtl9301-mdio.yaml@@ -0,0 +1,93 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/net/realtek,rtl9301-mdio.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Realtek RTL9300 MDIO Controller + +maintainers: + - Chris Packham <chris.packham@alliedtelesis.co.nz> + +properties: + compatible: + oneOf: + - items: + - enum: + - realtek,rtl9302b-mdio + - realtek,rtl9302c-mdio + - realtek,rtl9303-mdio + - const: realtek,rtl9301-mdio + - const: realtek,rtl9301-mdio + + '#address-cells': + const: 1 + + '#size-cells': + const: 0 + +patternProperties: + '^mdio-bus@[0-4]$': + $ref: mdio.yaml# + + properties: + reg: + maxItems: 1 + + required: + - reg + + patternProperties: + '^ethernet-phy(@[a-f0-9]+)?':
Why is the unit address optional?
+ type: object + $ref: ethernet-phy.yaml# + + properties: + realtek,port: + $ref: /schemas/types.yaml#/definitions/uint32 + description: + The MDIO communication on the RTL9300 is abstracted by the switch. At + the software level communication uses the switch port to address the + PHY with the actual MDIO bus and address having been setup via the + parent mdio-bus and reg property.
I don't quite get why this cannot be the 'reg' property. I understood that 'reg' of this node is not really used? Or you meant here this 'reg', not parent's 'reg'? Best regards, Krzysztof