Re: [PATCH v4 1/2] dt-bindings: qcom,snps-dwc3: Add property indicating presence of eUSB2 phy

[Thinh Nguyen]

On Thu, Jul 16, 2026, Peter Chen wrote:
> On 26-07-17 00:06:37, Thinh Nguyen wrote:
> > > 
> > > I have seen fewer platforms use "phy_type" at dts for arm64, dwc3
> > > core uses it only for special cases and the code was added for
> > > ten years ago. For the default situation, we may not need to
> > > change DWC3_GUSB2PHYCFG_EUSB2OPMODE value for UTMI+, Thinh, is it
> > > correct?
> > > 
> > 
> > The GUSB2PHYCFG.eUSB2OPMODE is only relevant for host mode and mainly
> > for electrical compliance. Usually by default, the CoreConsultant
> > setting should have this set correctly. So not explicitly setting it
> > should be functionally fine (IIRC).
> > 
> > That said, this is separate from the GUSB2PHYCFG.PHYIF, which the core
> > uses dwc->hsphy_mode to indicate whether the UTMI interface is 8-bit or
> > 16-bit.
> > 
> 
> Why only rockchip uses this "phy_type" property, why other SoC vendors
> no this requirement for UTMI width setting? 
> 

Not just rockchip, some tegra and hikey also use it. Some old qcom dts
files also have it for ulpi.

It is typically set when the coreConsultant default differs from what
the platform needs, so the driver can override it with the correct
setting.

My point is that changing "phy_type" definition is more involved than it
looks. I'm open to alternatives.

Thanks,
Thinh