Re: [PATCH v5 1/9] dt-bindings: soc: qcom: eud: Add per-path child nodes for UTMI routing
Krzysztof Kozlowski <[email protected]> Fri, 7 Aug 2026 09:20:26 +0200
| Newsgroups | org.kernel.vger.linux-usb,org.kernel.vger.linux-arm-msm,org.kernel.vger.linux-devicetree,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <20260807-shrewd-white-mayfly-a8bfea@quoll> |
On Sun, Aug 02, 2026 at 08:15:26PM -0700, Elson Serrao wrote: > 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. Add > an SM8350 compatible for dual-path EUD topologies while retaining the > legacy ports representation for backward compatibility. > > Signed-off-by: Elson Serrao <[email protected]> > --- > .../bindings/soc/qcom/qcom,eud.yaml | 128 +++++++++++++++++- > 1 file changed, 127 insertions(+), 1 deletion(-) Reviewed-by: Krzysztof Kozlowski <[email protected]> Best regards, Krzysztof