[PATCH v2 1/3] dt-bindings: phy: qcom, usb-snps-femto-v2: Add phy override params bindings

Stephen Boyd swboyd at chromium.org
Thu Mar 3 14:23:42 PST 2022


Quoting Krzysztof Kozlowski (2022-03-03 07:59:22)
> On 03/03/2022 07:13, Sandeep Maheswaram wrote:
> > Add device tree bindings for SNPS phy tuning parameters.
> >
> > Signed-off-by: Sandeep Maheswaram <quic_c_sanm at quicinc.com>
> > ---
> >  .../bindings/phy/qcom,usb-snps-femto-v2.yaml       | 125 +++++++++++++++++++++
> >  1 file changed, 125 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/phy/qcom,usb-snps-femto-v2.yaml b/Documentation/devicetree/bindings/phy/qcom,usb-snps-femto-v2.yaml
> > index 0dfe691..227c097 100644
> > --- a/Documentation/devicetree/bindings/phy/qcom,usb-snps-femto-v2.yaml
> > +++ b/Documentation/devicetree/bindings/phy/qcom,usb-snps-femto-v2.yaml
> > @@ -50,6 +50,131 @@ properties:
> >    vdda33-supply:
> >      description: phandle to the regulator 3.3V supply node.
> >
> > +  qcom,hs-disconnect:
> > +    $ref: /schemas/types.yaml#/definitions/uint32
> > +    description:
> > +      This adjusts the voltage level for the threshold used to
> > +      detect a disconnect event at the host. Possible values are.
>
> ':', instead of full stop.
>
> > +      7 -> +21.56%
> > +      6 -> +17.43%
> > +      5 -> +13.32%
> > +      4 -> +9.73%
> > +      3 -> +6.3
> > +      2 -> +3.17%
> > +      1 -> 0, Design default%
>
> Use "default:" instead. Here and in other places.
>
> > +      0 -> -2.72%
>
> In current form this should be an enum... but actually current form is
> wrong. You should not store register values in DT. What if next version
> of hardware has a different meaning of these values?
>
> Instead, you should store here meaningful values, not register values.

+1

To emphasize one point, meaningful values typically have a unit of
measure, like Hz, ms, mV, etc. What are the percentages adjusting from?
Is it a percentage decrease from the input voltage?



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