Re: [PATCH V1 1/2] dt-bindings: dmaengine: Add support for ATCDMAC300 DMA engine

[CL Wang]

Hi Krzysztof,

Thank you for pointing this out.

"ATCDMAC300" is the IP block name of the DMA controller used in Andes SoC.
According to your suggestion, I have updated the binding to use SoC-specific
compatibles with "andestech,atcdmac300" as a fallback, as shown below:

-  const: andestech,atcdmac300
+  items:
+    - enum:
+        - andestech,qilai-dma
+    - const: andestech,atcdmac300
...
   dma-controller@f0c00000 {
-      compatible = "andestech,atcdmac300";
+      compatible = "andestech,qilai-dma", "andestech,atcdmac300";


Does this look aligned with the recommended DeviceTree binding convention?

Thanks again for your detailed feedback.

Best regards,
CL


On Tue, Oct 07, 2025 at 11:27:12PM +0900, Krzysztof Kozlowski wrote:
> [EXTERNAL MAIL]
> 
> On 07/10/2025 21:33, CL Wang wrote:
> > Hi Conor,
> >
> > Thanks for your review.
> >
> > Yes, the DMA driver supports the Qilai platform. I have updated the DTS binding as shown below.
> > Could you please take a look and let me know if anything still needs to be adjusted?
> >
> >  properties:
> >    compatible:
> > -    const: andestech,atcdmac300
> > +    oneOf:
> > +      - items:
> > +          - enum:
> > +              - andestech,qilai-dma
> > +          - const: andestech,atcdmac300
> > +      - const: andestech,atcdmac300
> > ...
> >          dma-controller@f0c00000 {
> > -            compatible = "andestech,atcdmac300";
> > +            compatible = "andestech,qilai-dma", "andestech,atcdmac300";
> 
> What is "atcdmac300" then? Usually the recommendation is to go only with
> soc-based compatibles, not IP blocks. See also:
> 
> https://elixir.bootlin.com/linux/v6.17.1/source/Documentation/devicetree/bindings/writing-bindings.rst#L42
> 
> Best regards,
> Krzysztof