Re: [PATCH v6 3/9] usb: misc: qcom_eud: add per-path High-Speed PHY control
Konrad Dybcio <[email protected]>
| Newsgroups | org.kernel.vger.linux-kernel,org.kernel.vger.linux-arm-msm,org.kernel.vger.linux-devicetree,org.kernel.vger.linux-usb |
|---|---|
| Message-ID | <[email protected]> |
On 8/11/26 11:36 PM, Elson Serrao wrote: > EUD hardware can support multiple High-Speed USB paths, each routed > through its own PHY. The active path is selected in hardware via the > EUD_PORT_SEL register. As a High-Speed hub, EUD requires access to > the High-Speed PHY associated with the active path. To support this > multi-path capability, the driver must manage PHY resources on a > per-path basis, ensuring that the PHY for the currently selected > path is properly initialized and powered. > > This patch restructures the driver to implement per-path PHY management. > The driver now powers the appropriate PHY based on the selected and > enabled UTMI path, ensuring correct operation when EUD is enabled. > > Historically, EUD appeared to work on single-path systems because the > USB controller kept the PHY initialized. However, EUD is designed to > operate independently of the USB controller and therefore requires > explicit PHY control for proper operation. > > Reviewed-by: Peter Chen <[email protected]> > Signed-off-by: Elson Serrao <[email protected]> > --- Reviewed-by: Konrad Dybcio <[email protected]> Konrad