Re: [PATCHv2 1/2] dt-bindings: usb: dwc2: add support for STM32MP15 SoCs USB OTG HS and FS

[Amelie DELAUNAY]

On 1/17/20 3:48 PM, Rob Herring wrote:
> On Thu, Jan 16, 2020 at 03:45:23PM +0100, Amelie Delaunay wrote:
> > Add the specific compatible string for the DWC2 IP found in the STM32MP15
> > SoCs.
> > STM32MP15 SoCs uses sensing comparators to detect Vbus valid levels and
> > ID pin state. usb33d-supply described the regulator supplying Vbus and ID
> > sensing comparators.
> >
> > Signed-off-by: Amelie Delaunay <amelie.delaunay@xxxxxx>
> > ---
> >   Documentation/devicetree/bindings/usb/dwc2.yaml | 6 ++++++
> >   1 file changed, 6 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/usb/dwc2.yaml b/Documentation/devicetree/bindings/usb/dwc2.yaml
> > index 71cf7ba32237..0b86250b97a9 100644
> > --- a/Documentation/devicetree/bindings/usb/dwc2.yaml
> > +++ b/Documentation/devicetree/bindings/usb/dwc2.yaml
> > @@ -58,6 +58,8 @@ properties:
> >         - const: st,stm32f4x9-fsotg
> >         - const: st,stm32f4x9-hsotg
> >         - const: st,stm32f7-hsotg
> > +      - const: st,stm32mp15-fsotg
> > +      - const: st,stm32mp15-hsotg
> >         - const: samsung,s3c6400-hsotg
> >   
> >     reg:
> > @@ -103,6 +105,10 @@ properties:
> >     vusb_a-supply:
> >       description: phandle to voltage regulator of analog section.
> >   
> > +  vusb33d_supply:
>
> Not a valid regulator property.

arrgh, was ok in the v1 in .txt. Will send a v3 fixing it with 
vusb33d-supply instead.

> > +    description: reference to the external VBUS and ID sensing comparators, in
> > +      order to perform OTG operation, used on STM32MP15 SoCs.
>
> Are they external or part of the SoC? When we have Vbus sense and ID
> GPIOs, those go in the connector node, so this probably should too if
> these are board components.

Yes, they are part of the SoC but external of the DWC2 IP. You can find 
them in the box "3V3 USB Detector" of PWR block diagram of STM32MP15x 
[1]. In OTG block diagram also, it corresponds to "OTG detection" box.
Behind this vusb33d supply, it is a regulator provided by PWR regulator 
driver. Maybe I should say "reference to the VBUS and ID sensing 
comparators *supply*.

[1] 
https://www.st.com/content/ccc/resource/technical/document/reference_manual/group0/51/ba/9e/5e/78/5b/4b/dd/DM00327659/files/DM00327659.pdf/jcr:content/translations/en.DM00327659.pdf

Regards,
Amelie

> Rob