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

[Thinh Nguyen <Thinh.Nguyen@synopsys.com>]

On Mon, Jul 13, 2026, Peter Chen wrote:
> On 26-07-13 08:26:59, Krzysztof Kozlowski wrote:
> > >> And Dmitry already said this at v3.
> > > 
> > > And I've already responded to his comment in v3:
> > > https://urldefense.com/v3/__https://lore.kernel.org/linux-usb/ahjYwJtiMsm0BcCh@vbox/__;!!A4F2R9G_pg!YksJ0tPtRth9ez8t0GB_WaxH3ynx3ya8M8aFIyKfYpApRC_79Ig93CqE2MKcrGJ6O6t_Dl3RD1zftrnxhdtcfoW7hgep8w$ 
> > 
> > It does not change the fact that type of phy is implied by compatible,
> > thus you do not get a new property.
> > 
> > 
> 
> For USB2 PHY, it has property "phy_type" already, it could extend support
> list to eUSB2 like below, dwc3 qcom glue layer could call of_usb_get_phy_mode
> or re-use dwc3->hsphy_mode depends on where it needs to use.
> 
> diff --git a/drivers/usb/phy/of.c b/drivers/usb/phy/of.c
> index 1ab134f45d67..5cbf17d493ad 100644
> --- a/drivers/usb/phy/of.c
> +++ b/drivers/usb/phy/of.c
> @@ -16,6 +16,7 @@ static const char *const usbphy_modes[] = {
>  	[USBPHY_INTERFACE_MODE_ULPI]	= "ulpi",
>  	[USBPHY_INTERFACE_MODE_SERIAL]	= "serial",
>  	[USBPHY_INTERFACE_MODE_HSIC]	= "hsic",
> +	[USBPHY_INTERFACE_MODE_EUSB2]	= "eusb2",
>  };
> 
> 

eusb2 uses utmi, so it doesn't fit here as a separate mode.

To go this route properly, we'd need to introduce a new phy type
attribute in the phy framework, which will be a bigger change that may
impact more than this driver.

Thanks,
Thinh