Re: [PATCH 1/2] dt-bindings: display: solomon,ssd132x: Add col-offset and dclk properties for the SSD1322

[Fabio Piparo]

On Fri, Oct 30, 2026 at 8:06 AM Krzysztof Kozlowski <krzk@xxxxxxxxxx> wrote:
> On Thu, Oct 29, 2026 at 04:57:50PM -0400, Fabio Piparo wrote:
> > +  solomon,dclk-div:
> > +    $ref: /schemas/types.yaml#/definitions/uint32
> > +    enum: [1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024]
> > +    default: 2
> > +    description:
> > +      Clock divisor.
>
> Why this cannot be deduced from clock frequency?

On this module the SSD1322 runs from its internal oscillator, and the
external clock pin is not on the ribbon. These two values only set how
often the panel redraws.

> > +  solomon,dclk-frq:
> > +    $ref: /schemas/types.yaml#/definitions/uint32
>
> Use either existing properties or - if there aren't such - existing unit
> suffixes.
>
> > +    minimum: 0
> > +    maximum: 15
> > +    default: 9
> > +    description:
> > +      Clock frequency, higher value means higher frequency.
>
> Why would the frequency be fixed/static?

Right, it doesn't need to be, and I'll drop both properties in v2.

I still need the redraw rate to be adjustable. I drive this panel at
about 200 FPS, and at the default clock it redraws at about
115 times a second. One way would be to offer the 256x64 mode
at a few refresh rates and set the clock divider from the mode
userspace picks, the way panel-newvision-nv3051d offers
640x480 at 60, 100 and 120 Hz. The rates would be approximate
since the panel's oscillator is not exact, is this a good way to do it
here?

Thanks,
Fabio