On Wed, Dec 16, 2020 at 07:17:05PM +0200, Laurent Pinchart wrote: > On Wed, Dec 16, 2020 at 07:05:34PM +0200, Laurent Pinchart wrote: > > Hi Jacopo, > > > > Thank you for the patch. > > > > On Tue, Dec 15, 2020 at 06:09:54PM +0100, Jacopo Mondi wrote: > > > Document the 'reverse-channel-microvolt' 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 <[email protected]> > > > Signed-off-by: Jacopo Mondi <[email protected]> > > > > Reviewed-by: Laurent Pinchart <[email protected]> > > > > > --- > > > v5->v6: > > > - Use standard unit suffix 'microvolt' for the custom property > > > - Drop '$ref' as according to 'example-schema.yaml': > > > "Vendor specific properties having a standard unit suffix don't need a > > > type." > > > --- > > > .../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..b22ba3e0db4a 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,reverse-channel-microvolt: > > > + minimum: 30000 > > > + maximum: 200000 > > > + default: 170000 > > > + description: | > > > + Initial amplitude of the reverse control channel, in micro volts. > > > + > > > + 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 > > > + 170000 micro volts. > > > + > > > + A typical value for the reverse channel amplitude to communicate > > > with > > > + a remote serializer whose high-threshold noise immunity is not > > > enabled > > > + is 100000 micro volts > > > + > > > ports: > > > type: object > > > description: | > > > @@ -221,6 +241,7 @@ required: > > > - ports > > > - i2c-mux > > > - gpio-controller > > > + - maxim,reverse-channel-microvolt > > One comment though: You specify a default value above, which isn't very > useful when the property is required. Should we either drop the default > value, or make the property optional ?
And generally added properties can't be required unless for some reason DT's without the property are broken. With required dropped, Reviewed-by: Rob Herring <[email protected]> Rob
