Re: [PATCH v3 1/3] dt-bindings: rtc: loongson: Correct Loongson-1C interrupts property

[Alexandre Belloni <alexandre.belloni@bootlin.com>]

On 19/01/2026 18:24:36+0000, Conor Dooley wrote:
> On Sat, Jan 17, 2026 at 10:26:48AM +0800, Binbin Zhou wrote:
> > The `interrupts` property indicates an RTC alarm interrupt, which is
> > required for RTCs that support the alarm feature, which is not supported
> > by the Loongson-1C RTC. We exclude it for a more accurate description.
> > 
> > Changing the `allowed` property is ABI-breaking behavior, but
> > throughout the existing Loongson DTS{i}, the description of the RTC
> > nodes conforms to the modified bingding rules.
> 
> Right, changing properties is an ABI break, but when following the ABI
> would've produced something non-functional, breaking it is not really
> relevant.


But the HW has the interrupt, the fact that is not functional doesn't
mean it isn't there. I thought we should describe the hardware?

> Acked-by: Conor Dooley <conor.dooley@microchip.com>
> pw-bot: not-applicable
> 
> > 
> > Thus, the existing Loongson DTS{i} will not be affected.
> > 
> > Fixes: 487ef32caebe ("dt-bindings: rtc: Split loongson,ls2x-rtc into SoC-based compatibles")
> > Reviewed-by: Huacai Chen <chenhuacai@loongson.cn>
> > Signed-off-by: Binbin Zhou <zhoubinbin@loongson.cn>
> > ---
> >  .../devicetree/bindings/rtc/loongson,rtc.yaml         | 11 +++++++++++
> >  1 file changed, 11 insertions(+)
> > 
> > diff --git a/Documentation/devicetree/bindings/rtc/loongson,rtc.yaml b/Documentation/devicetree/bindings/rtc/loongson,rtc.yaml
> > index f89c1f660aee..fac90a18153e 100644
> > --- a/Documentation/devicetree/bindings/rtc/loongson,rtc.yaml
> > +++ b/Documentation/devicetree/bindings/rtc/loongson,rtc.yaml
> > @@ -42,6 +42,17 @@ required:
> >  
> >  unevaluatedProperties: false
> >  
> > +if:
> > +  properties:
> > +    compatible:
> > +      contains:
> > +        enum:
> > +          - loongson,ls1c-rtc
> > +
> > +then:
> > +  properties:
> > +    interrupts: false
> > +
> >  examples:
> >    - |
> >      #include <dt-bindings/interrupt-controller/irq.h>
> > -- 
> > 2.47.3
> > 



-- 
Alexandre Belloni, co-owner and COO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com