[PATCH v8 1/8] dt-bindings: soc: qcom: eud: Add per-path child nodes for UTMI routing
From: Elson Serrao <hidden>
Date: 2026-09-12 22:53:07
Also in:
linux-arm-msm, linux-devicetree, lkml
Subsystem:
arm/qualcomm mailing list, arm/qualcomm support, open firmware and flattened device tree bindings, qcom embedded usb debugger (eud), the rest · Maintainers:
Bjorn Andersson, Konrad Dybcio, Rob Herring, Krzysztof Kozlowski, Conor Dooley, Souradeep Chowdhury, Linus Torvalds
The Qualcomm Embedded USB Debugger (EUD) can intercept one or two High-Speed UTMI paths depending on the SoC. For example, SC7280 supports EUD on the primary UTMI path only, while SM8350 supports EUD on both primary and secondary UTMI paths. Each UTMI path connects an independent USB controller/connector pair and forms its own role-switch domain. EUD routes traffic based on USB role. In device role the debug hub is inserted, while in host role it is bypassed. The existing binding models EUD using a flattened ports representation. While sufficient for fixed device-role configurations, it cannot naturally associate a controller, connector, and role switch with a specific EUD-routable path. This is problematic for role-switch capable ports and becomes more pronounced on SoCs with multiple paths. In such cases, each path forms an independent role-switch domain and requires per-path role awareness. Model each UTMI path as a separate child node with its own OF graph. This representation is used for role-aware EUD routing regardless of whether a SoC exposes one or two UTMI paths. Add an SM8350 compatible for dual-path EUD topologies. Retain support for the legacy flat ports representation on SC7280 for backward compatibility. Reviewed-by: Krzysztof Kozlowski <redacted> Acked-by: Bjorn Andersson <andersson@kernel.org> Signed-off-by: Elson Serrao <redacted> --- .../bindings/soc/qcom/qcom,eud.yaml | 138 +++++++++++++++++- 1 file changed, 137 insertions(+), 1 deletion(-)
diff --git a/Documentation/devicetree/bindings/soc/qcom/qcom,eud.yaml b/Documentation/devicetree/bindings/soc/qcom/qcom,eud.yaml
index 84218636c0d8..90dc104e4475 100644
--- a/Documentation/devicetree/bindings/soc/qcom/qcom,eud.yaml
+++ b/Documentation/devicetree/bindings/soc/qcom/qcom,eud.yaml@@ -18,6 +18,7 @@ properties: items: - enum: - qcom,sc7280-eud + - qcom,sm8350-eud - const: qcom,eud reg:
@@ -45,10 +46,92 @@ properties: $ref: /schemas/graph.yaml#/properties/port description: This port is to be attached to the type C connector. + '#address-cells': + const: 1 + + '#size-cells': + const: 0 + +patternProperties: + "^eud-path@[0-1]$": + type: object + description: + Represents one High-Speed UTMI path that EUD intercepts. Use eud-path nodes + to associate role-switching behavior with specific port connections, allowing + EUD to manage role transitions independently for each UTMI path. + + properties: + reg: + maxItems: 1 + description: Path number + + usb-role-switch: + type: boolean + description: + Indicates that EUD relays USB role-switch events for this path and + performs role-dependent UTMI routing accordingly. In device role, + the EUD hub is inserted into this path to enable debug + functionality. In host role, the EUD hub is bypassed and UTMI + traffic flows directly between the PHY and the USB controller. + + ports: + $ref: /schemas/graph.yaml#/properties/ports + description: + These ports are to be attached to the endpoint of the USB controller node + and USB connector node. + + properties: + port@0: + $ref: /schemas/graph.yaml#/properties/port + description: This port is to be attached to the USB controller. + + port@1: + $ref: /schemas/graph.yaml#/properties/port + description: This port is to be attached to the USB connector. + + required: + - reg + - ports + + additionalProperties: false + required: - compatible - reg - - ports + +allOf: + - if: + properties: + compatible: + contains: + const: qcom,sc7280-eud + then: + oneOf: + - required: + - ports + properties: + eud-path@0: false + eud-path@1: false + - required: + - eud-path@0 + - '#address-cells' + - '#size-cells' + properties: + ports: false + eud-path@1: false + - if: + properties: + compatible: + contains: + const: qcom,sm8350-eud + then: + required: + - eud-path@0 + - eud-path@1 + - '#address-cells' + - '#size-cells' + properties: + ports: false additionalProperties: false
@@ -77,3 +160,56 @@ examples: }; }; }; + - | + eud@88e0000 { + compatible = "qcom,sm8350-eud", "qcom,eud"; + reg = <0x88e0000 0x2000>, + <0x88e2000 0x1000>; + #address-cells = <1>; + #size-cells = <0>; + + eud-path@0 { + reg = <0>; + usb-role-switch; + + ports { + #address-cells = <1>; + #size-cells = <0>; + port@0 { + reg = <0>; + eud_usb0: endpoint { + remote-endpoint = <&usb_1_dwc3_hs>; + }; + }; + + port@1 { + reg = <1>; + eud_con0: endpoint { + remote-endpoint = <&pmic_glink_hs_in>; + }; + }; + }; + }; + + eud-path@1 { + reg = <1>; + + ports { + #address-cells = <1>; + #size-cells = <0>; + port@0 { + reg = <0>; + eud_usb1: endpoint { + remote-endpoint = <&usb_2_dwc3_hs>; + }; + }; + + port@1 { + reg = <1>; + eud_con1: endpoint { + remote-endpoint = <&conn_2_hs_in>; + }; + }; + }; + }; + };
--
2.34.1