[v3,2/4] dt-bindings: phy: qcom,qmp: Describe 'vdda-max-microamp' & 'vdda-pll-max-microamp' properties

Since a few boards based on QCoM qmp phy use the
'vdda-max-microamp' & 'vdda-pll-max-microamp' properties to
describe the ufs phy nodes, add them to the dt-bindings doc as well.

This fixes the following '$ make dtbs_check' warning(s):

sm8350-microsoft-surface-duo2.dt.yaml: phy@1d87000:
  'vdda-max-microamp', 'vdda-pll-max-microamp' do not match any of
   the regexes: '^phy@[0-9a-f]+$', 'pinctrl-[0-9]+'

Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Vinod Koul <vkoul@kernel.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Bhupesh Sharma <bhupesh.sharma@linaro.org>
---
 Documentation/devicetree/bindings/phy/qcom,qmp-phy.yaml | 8 ++++++++
 1 file changed, 8 insertions(+)

On Tue, 19 Apr 2022 at 04:04, Dmitry Baryshkov
<dmitry.baryshkov@linaro.org> wrote:
>
> On Mon, 18 Apr 2022 at 23:55, Bhupesh Sharma <bhupesh.sharma@linaro.org> wrote:
> >
> > Since a few boards based on QCoM qmp phy use the
> > 'vdda-max-microamp' & 'vdda-pll-max-microamp' properties to
> > describe the ufs phy nodes, add them to the dt-bindings doc as well.
>
> Ugh. They give a false sense that they are supported. I think in
> reality they are not used by the kernel.
> So, ideally, this patch should be accompanied with regulator core change.
> Or (better) drop them completely.

Indeed. However, the earlier reviews were contrary to this
understanding. Maybe, @Bjorn Andersson can help with more background
on the same.

Although I agree that since this appears mainly in sm8450 and sm8350
dts and is relevant for ufs qmp phy nodes, I can send patches for
cleaning up the dts files instead.

My hunch is that these have been copied over into the qcom dts/dtsi
files from the similar  ones described in [1].

[1]. https://www.kernel.org/doc/Documentation/devicetree/bindings/ufs/ufs-qcom.txt

Thanks,
Bhupesh


> >
> > This fixes the following '$ make dtbs_check' warning(s):
> >
> > sm8350-microsoft-surface-duo2.dt.yaml: phy@1d87000:
> >   'vdda-max-microamp', 'vdda-pll-max-microamp' do not match any of
> >    the regexes: '^phy@[0-9a-f]+$', 'pinctrl-[0-9]+'
> >
> > Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
> > Cc: Vinod Koul <vkoul@kernel.org>
> > Acked-by: Rob Herring <robh@kernel.org>
> > Signed-off-by: Bhupesh Sharma <bhupesh.sharma@linaro.org>
> > ---
> >  Documentation/devicetree/bindings/phy/qcom,qmp-phy.yaml | 8 ++++++++
> >  1 file changed, 8 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/phy/qcom,qmp-phy.yaml b/Documentation/devicetree/bindings/phy/qcom,qmp-phy.yaml
> > index c39ead81ecd7..411c79dbfa15 100644
> > --- a/Documentation/devicetree/bindings/phy/qcom,qmp-phy.yaml
> > +++ b/Documentation/devicetree/bindings/phy/qcom,qmp-phy.yaml
> > @@ -90,6 +90,14 @@ properties:
> >      minItems: 1
> >      maxItems: 3
> >
> > +  vdda-max-microamp:
> > +    description:
> > +      Specifies max. load that can be drawn from phy supply.
> > +
> > +  vdda-pll-max-microamp:
> > +    description:
> > +      Specifies max. load that can be drawn from pll supply.
> > +
> >    vdda-phy-supply:
> >      description:
> >        Phandle to a regulator supply to PHY core block.
> > --
> > 2.35.1
> >
>
>
> --
> With best wishes
> Dmitry

On Mon 18 Apr 13:55 PDT 2022, Bhupesh Sharma wrote:

> Since a few boards based on QCoM qmp phy use the
> 'vdda-max-microamp' & 'vdda-pll-max-microamp' properties to
> describe the ufs phy nodes, add them to the dt-bindings doc as well.
> 
> This fixes the following '$ make dtbs_check' warning(s):
> 
> sm8350-microsoft-surface-duo2.dt.yaml: phy@1d87000:
>   'vdda-max-microamp', 'vdda-pll-max-microamp' do not match any of
>    the regexes: '^phy@[0-9a-f]+$', 'pinctrl-[0-9]+'
> 
> Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
> Cc: Vinod Koul <vkoul@kernel.org>
> Acked-by: Rob Herring <robh@kernel.org>
> Signed-off-by: Bhupesh Sharma <bhupesh.sharma@linaro.org>
> ---
>  Documentation/devicetree/bindings/phy/qcom,qmp-phy.yaml | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/phy/qcom,qmp-phy.yaml b/Documentation/devicetree/bindings/phy/qcom,qmp-phy.yaml
> index c39ead81ecd7..411c79dbfa15 100644
> --- a/Documentation/devicetree/bindings/phy/qcom,qmp-phy.yaml
> +++ b/Documentation/devicetree/bindings/phy/qcom,qmp-phy.yaml
> @@ -90,6 +90,14 @@ properties:
>      minItems: 1
>      maxItems: 3
>  
> +  vdda-max-microamp:
> +    description:
> +      Specifies max. load that can be drawn from phy supply.
> +
> +  vdda-pll-max-microamp:
> +    description:
> +      Specifies max. load that can be drawn from pll supply.

It's not clear to me what an implementation would do with this
information. As expressed here it sounds like it's a property of the
specified regulator, so the driver should just request that information
from the regulator framework.

So let's wait with introducing such properties until we know.

Thanks,
Bjorn

> +
>    vdda-phy-supply:
>      description:
>        Phandle to a regulator supply to PHY core block.
> -- 
> 2.35.1
>