Re: [PATCH v2 1/5] dt-bindings: display: simple-framebuffer: Add interconnects property

[Thomas Zimmermann]

Hi

Am 03.07.25 um 10:34 schrieb Hans de Goede:
> Hi Thomas,
>
> On 3-Jul-25 8:47 AM, Thomas Zimmermann wrote:
> > Hi
> >
> > Am 02.07.25 um 22:43 schrieb Krzysztof Kozlowski:
> > > On 30/06/2025 10:40, Hans de Goede wrote:
> > > > > No one asks to drop them from the driver. I only want specific front
> > > > > compatible which will list and constrain the properties. It is not
> > > > > contradictory to your statements, U-boot support, driver support. I
> > > > > really do not see ANY argument why this cannot follow standard DT rules.
> > > > So what you are saying is that you want something like:
> > > >
> > > > framebuffer0: framebuffer@1d385000 {
> > > >      compatible = "qcom.simple-framebuffer-sm8650-mdss", "simple-framebuffer";
> > > > }
> > > >
> > > > and that the binding for qcom.simple-framebuffer-sm8650-mdss
> > > > can then list interconnects ?
> > > IMO yes (after adjusting above to coding style), but as mentioned in
> > > other response you can just get an ack or opinion from Rob or Conor.
> > But does that work with *any* device that requires interconnects? The next such simple-framebuffer device should work out of the box *without* the kernel knowing anything about it. That's one of the key features of the simple-framebuffer.  If we have to maintainer per-device feature sets, it breaks that assumption.
> The driver code for this can still be generic and since the driver
> will bind to the fallback plain "simple-framebuffer" compatible
> this should also work for new platforms.
>
> The e.g. "qcom.simple-framebuffer-sm8650-mdss" compatible would
> purely be something in the dt-bindings to document which simplefb
> implementations will have interconnects and which ones will not.
>
> The driver does not necessarily need to check these more
> precise compatibles, it can still just check for the generic
> presence of interconnects.

Thanks, that's good to hear.

Best regards
Thomas

> Regards,
>
> Hans

--
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Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
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