[PATCH net-next 12/15] dt-bindings: net: dsa: sja1105: document the PCS nodes

From: Vladimir Oltean

Date: Tue Nov 18 2025 - 14:06:10 EST


The XPCS blocks in NXP SJA1105 and SJA1110 may be described in the
device tree, and they follow the same bindings as the other instances
which are memory-mapped using an APB3 or MCI interface.

Document their compatible string, positioning in the switch's "regs"
subnode, and the pcs-handle to them.

The "type: object" addition in the ethernet-port node is to suppress
a dt_binding_check warning that states "node schemas must have a type
or $ref". This is fine, but I don't completely understand why it started
being required just now (apparently, the presence of "properties" under
the port node affects this).

Cc: Rob Herring <robh@xxxxxxxxxx>
Cc: Krzysztof Kozlowski <krzk+dt@xxxxxxxxxx>
Cc: Conor Dooley <conor+dt@xxxxxxxxxx>
Cc: devicetree@xxxxxxxxxxxxxxx
Signed-off-by: Vladimir Oltean <vladimir.oltean@xxxxxxx>
---
.../bindings/net/dsa/nxp,sja1105.yaml | 28 +++++++++++++++++++
.../bindings/net/pcs/snps,dw-xpcs.yaml | 8 ++++++
2 files changed, 36 insertions(+)

diff --git a/Documentation/devicetree/bindings/net/dsa/nxp,sja1105.yaml b/Documentation/devicetree/bindings/net/dsa/nxp,sja1105.yaml
index 607b7fe8d28e..ee1a95d6b032 100644
--- a/Documentation/devicetree/bindings/net/dsa/nxp,sja1105.yaml
+++ b/Documentation/devicetree/bindings/net/dsa/nxp,sja1105.yaml
@@ -85,11 +85,31 @@ properties:
- compatible
- reg

+ regs:
+ type: object
+ description:
+ Optional container node for peripherals in the switch address space other
+ than the switching IP itself. This node and its children only need to be
+ described if board-specific properties need to be specified, like SerDes
+ lane polarity inversion. If absent, default descriptions are used.
+ additionalProperties: false
+
+ properties:
+ '#address-cells':
+ const: 1
+ '#size-cells':
+ const: 1
+
+ patternProperties:
+ "^ethernet-pcs@[0-9a-f]+$":
+ $ref: /schemas/net/pcs/snps,dw-xpcs.yaml#
+
patternProperties:
"^(ethernet-)?ports$":
additionalProperties: true
patternProperties:
"^(ethernet-)?port@[0-9]$":
+ type: object
allOf:
- if:
properties:
@@ -107,6 +127,14 @@ patternProperties:
tx-internal-delay-ps:
$ref: "#/$defs/internal-delay-ps"

+ properties:
+ pcs-handle:
+ $ref: /schemas/types.yaml#/definitions/phandle
+ description:
+ Phandle to a PCS device node from the "regs" container.
+ Can be skipped if the PCS description is missing - in that case,
+ the connection is implicit.
+
required:
- compatible
- reg
diff --git a/Documentation/devicetree/bindings/net/pcs/snps,dw-xpcs.yaml b/Documentation/devicetree/bindings/net/pcs/snps,dw-xpcs.yaml
index e77eec9ac9ee..46e4f611f714 100644
--- a/Documentation/devicetree/bindings/net/pcs/snps,dw-xpcs.yaml
+++ b/Documentation/devicetree/bindings/net/pcs/snps,dw-xpcs.yaml
@@ -25,6 +25,14 @@ description:
properties:
compatible:
oneOf:
+ - description:
+ Synopsys DesignWare XPCS in NXP SJA1105 switch (direct APB3 access
+ via SPI) with custom PMA
+ const: nxp,sja1105-pcs
+ - description:
+ Synopsys DesignWare XPCS in NXP SJA1110 switch (indirect APB3 access
+ via SPI) with custom PMA
+ const: nxp,sja1110-pcs
- description: Synopsys DesignWare XPCS with none or unknown PMA
const: snps,dw-xpcs
- description: Synopsys DesignWare XPCS with Consumer Gen1 3G PMA
--
2.34.1