[PATCH 1/5] media: dt-bindings: media: imx335: Add supply bindings

[Kieran Bingham]

Hi Sakari,

Quoting Sakari Ailus (2023-10-10 07:06:26)
> Hi Kieran,
> 
> On Tue, Oct 10, 2023 at 01:51:22AM +0100, Kieran Bingham wrote:
> > Add the bindings for the supply references used on the IMX335.
> > 
> > Signed-off-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
> > ---
> >  .../bindings/media/i2c/sony,imx335.yaml          | 16 ++++++++++++++++
> >  1 file changed, 16 insertions(+)
> > 
> > diff --git a/Documentation/devicetree/bindings/media/i2c/sony,imx335.yaml b/Documentation/devicetree/bindings/media/i2c/sony,imx335.yaml
> > index a167dcdb3a32..1863b5608a5c 100644
> > --- a/Documentation/devicetree/bindings/media/i2c/sony,imx335.yaml
> > +++ b/Documentation/devicetree/bindings/media/i2c/sony,imx335.yaml
> > @@ -32,6 +32,15 @@ properties:
> >      description: Clock frequency from 6 to 27 MHz, 37.125MHz, 74.25MHz
> >      maxItems: 1
> >  
> > +  avdd-supply:
> > +    description: Analog power supply (2.9V)
> > +
> > +  ovdd-supply:
> > +    description: Interface power supply (1.8V)
> > +
> > +  dvdd-supply:
> > +    description: Digital power supply (1.2V)
> 
> I wonder what's the policy in this case --- some of the regulators are
> often hard-wired and the bindings didn't have them previously either (I
> wonder why, maybe they were all hard wired in the board??).
> 
> Could they be optional? The driver will need to be able to do without these
> in any case.

Indeed - many devices do not need to define how they are powered up.

But Krzysztof stated that supplies should be required by the bindings on
my recent posting for a VCM driver:

 - https://lore.kernel.org/all/6e163f4d-061d-3c20-4c2e-44c74d529f10@linaro.org/

So based on that I have made these 'required'.

Even in my case here, with a camera module that is compatible with the
Raspberry Pi camera connector - there isn't really 3 supplies. It's just
a single gpio enable pin to bring this device up for me. Of course
that's specific to the module not the sensor.


> > +
> >    reset-gpios:
> >      description: Reference to the GPIO connected to the XCLR pin, if any.
> >      maxItems: 1
> > @@ -60,6 +69,9 @@ required:
> >    - compatible
> >    - reg
> >    - clocks
> > +  - avdd-supply
> > +  - ovdd-supply
> > +  - dvdd-supply
> >    - port
> >  
> >  additionalProperties: false
> > @@ -79,6 +91,10 @@ examples:
> >              assigned-clock-parents = <&imx335_clk_parent>;
> >              assigned-clock-rates = <24000000>;
> >  
> > +            avdd-supply = <&camera_vdda_2v9>;
> > +            ovdd-supply = <&camera_vddo_1v8>;
> > +            dvdd-supply = <&camera_vddd_1v2>;
> > +
> >              port {
> >                  imx335: endpoint {
> >                      remote-endpoint = <&cam>;
> 
> -- 
> Kind regards,
> 
> Sakari Ailus