Re: [PATCH v5 2/8] dt-bindings: media: max9286: Document 'maxim,initial-reverse-channel-mV'

From: Jacopo Mondi
Date: Tue Dec 15 2020 - 06:15:28 EST


Hello,

On Mon, Nov 30, 2020 at 03:00:48PM -0700, Rob Herring wrote:
> On Mon, Nov 16, 2020 at 02:52:59PM +0100, Jacopo Mondi wrote:
> > Document the 'initial-reverse-channel-mV' vendor property in the
> > bindings document of the max9286 driver.
> >
> > The newly introduced property allows to specifying the initial
> > configuration of the GMSL reverse control channel to accommodate
> > remote serializers pre-programmed with the high threshold power
> > supply noise immunity enabled.
> >
> > Reviewed-by: Kieran Bingham <kieran.bingham+renesas@xxxxxxxxxxxxxxxx>
> > Signed-off-by: Jacopo Mondi <jacopo+renesas@xxxxxxxxxx>
> > ---
> > .../bindings/media/i2c/maxim,max9286.yaml | 23 +++++++++++++++++++
> > 1 file changed, 23 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/media/i2c/maxim,max9286.yaml b/Documentation/devicetree/bindings/media/i2c/maxim,max9286.yaml
> > index 9ea827092fdd..f61234d204fa 100644
> > --- a/Documentation/devicetree/bindings/media/i2c/maxim,max9286.yaml
> > +++ b/Documentation/devicetree/bindings/media/i2c/maxim,max9286.yaml
> > @@ -51,6 +51,26 @@ properties:
> > '#gpio-cells':
> > const: 2
> >
> > + maxim,initial-reverse-channel-mV:
>
> Use standard unit suffix.
>

Which one ? :)
I see in v5.10 one 'mV', three 'mv', one 'millivolts', several
'microvolts'.

I'll go with the majority and make this
'maxim,initial-reverse-channel-mv'

Thanks
j

> > + $ref: '/schemas/types.yaml#/definitions/uint32'
> > + minimum: 30
> > + maximum: 200
> > + default: 170
> > + description: |
> > + Initial amplitude of the reverse control channel, in millivolts.
> > +
> > + The initial amplitude shall be adjusted to a value compatible with the
> > + configuration of the connected remote serializer.
> > +
> > + Some camera modules (for example RDACM20) include an on-board MCU that
> > + pre-programs the embedded serializer with power supply noise immunity
> > + (high-threshold) enabled. A typical value of the deserializer's reverse
> > + channel amplitude to communicate with pre-programmed serializers is 170mV.
> > +
> > + A typical value for the reverse channel amplitude to communicate with
> > + a remote serializer whose high-threshold noise immunity is not enabled
> > + is 100mV.
> > +
> > ports:
> > type: object
> > description: |
> > @@ -221,6 +241,7 @@ required:
> > - ports
> > - i2c-mux
> > - gpio-controller
> > + - maxim,initial-reverse-channel-mV
> >
> > additionalProperties: false
> >
> > @@ -243,6 +264,8 @@ examples:
> > gpio-controller;
> > #gpio-cells = <2>;
> >
> > + maxim,initial-reverse-channel-mV = <170>;
> > +
> > ports {
> > #address-cells = <1>;
> > #size-cells = <0>;
> > --
> > 2.29.1
> >