On 29/06/2025 14:07, Hans de Goede wrote: > Hi Krzysztof, > > On 28-Jun-25 1:49 PM, Krzysztof Kozlowski wrote: >> On 27/06/2025 11:48, Luca Weiss wrote: >>> Hi Krzysztof, >>> >>> On Fri Jun 27, 2025 at 10:08 AM CEST, Krzysztof Kozlowski wrote: >>>> On Mon, Jun 23, 2025 at 08:44:45AM +0200, Luca Weiss wrote: >>>>> Document the interconnects property which is a list of interconnect >>>>> paths that is used by the framebuffer and therefore needs to be kept >>>>> alive when the framebuffer is being used. >>>>> >>>>> Acked-by: Thomas Zimmermann <[email protected]> >>>>> Signed-off-by: Luca Weiss <[email protected]> >>>>> --- >>>>> Documentation/devicetree/bindings/display/simple-framebuffer.yaml | 3 +++ >>>>> 1 file changed, 3 insertions(+) >>>>> >>>>> diff --git >>>>> a/Documentation/devicetree/bindings/display/simple-framebuffer.yaml >>>>> b/Documentation/devicetree/bindings/display/simple-framebuffer.yaml >>>>> index >>>>> 296500f9da05e296dbbeec50ba5186b6b30aaffc..f0fa0ef23d91043dfb2b220c654b80e2e80850cd >>>>> 100644 >>>>> --- a/Documentation/devicetree/bindings/display/simple-framebuffer.yaml >>>>> +++ b/Documentation/devicetree/bindings/display/simple-framebuffer.yaml >>>>> @@ -79,6 +79,9 @@ properties: >>>>> power-domains: >>>>> description: List of power domains used by the framebuffer. >>>>> >>>>> + interconnects: >>>>> + description: List of interconnect paths used by the framebuffer. >>>>> + >>>> >>>> maxItems: 1, or this is not a simple FB anymore. Anything which needs >>>> some sort of resources in unknown way is not simple anymore. You need >>>> device specific bindings. >>> >>> The bindings support an arbitrary number of clocks, regulators, >>> power-domains. Why should I artificially limit the interconnects to only >>> one? >> >> And IMO they should not. Bindings are not supposed to be generic. > > The simplefb binding is a binding to allow keeping the firmware, e.g. > uboot setup framebuffer alive to e.g. show a boot splash until > the native display-engine drive loads. Needing display-engine > specific bindings totally contradicts the whole goal of
No, it does not. DT is well designed for that through expressing compatibility. I did not say you cannot have generic fallback for simple use case. But this (and previous patchset) grows this into generic binding ONLY and that is not correct. > > It is generic by nature and I really do not see how clocks and > regulators are any different then interconnects here. Yeah, they are also wrong. I already commented on this. > > Note that we had a huge discussion about adding clock > and regulators to simplefb many years ago with pretty > much the same arguments against doing so. In the end it was > decided to add regulator and clocks support to the simplefb > bindings and non of the feared problems with e.g. ordening > of turning things on happened. > > A big part of this is that the claiming of clks / regulators / > interconnects by the simplefb driver is there to keep things on, > so it happens before the kernel starts tuning off unused resources > IOW everything is already up and running and this really is about > avoiding turning things off. 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. Best regards, Krzysztof
