Re: [PATCH] dt-bindings: dma: sprd,sc9860-dma: convert to YAML

[Stanislav Jakubek <stano.jakubek@gmail.com>]

Hi Conor,
see below.

On Thu, Jul 04, 2024 at 05:42:39PM +0100, Conor Dooley wrote:
> On Thu, Jul 04, 2024 at 05:18:09PM +0200, Stanislav Jakubek wrote:
> > Convert the Spreadtrum SC9860 DMA bindings to DT schema.
> > 
> > Changes during conversion:
> >   - rename file to match compatible
> >   - make interrupts optional, the AGCP DMA controller doesn't need it
> >   - describe the optional ashb_eb clock for the AGCP DMA controller
> > 
> > Signed-off-by: Stanislav Jakubek <stano.jakubek@gmail.com>
> > ---
> >  .../bindings/dma/sprd,sc9860-dma.yaml         | 92 +++++++++++++++++++
> >  .../devicetree/bindings/dma/sprd-dma.txt      | 44 ---------
> >  2 files changed, 92 insertions(+), 44 deletions(-)
> >  create mode 100644 Documentation/devicetree/bindings/dma/sprd,sc9860-dma.yaml
> >  delete mode 100644 Documentation/devicetree/bindings/dma/sprd-dma.txt
> > 
> > diff --git a/Documentation/devicetree/bindings/dma/sprd,sc9860-dma.yaml b/Documentation/devicetree/bindings/dma/sprd,sc9860-dma.yaml
> > new file mode 100644
> > index 000000000000..e1639593d26d
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/dma/sprd,sc9860-dma.yaml
> > @@ -0,0 +1,92 @@
> > +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/dma/sprd,sc9860-dma.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Spreadtrum SC9860 DMA controller
> > +
> > +description: |
> > +  There are three DMA controllers: AP DMA, AON DMA and AGCP DMA. For AGCP
> > +  DMA controller, it can or do not request the IRQ, which will save
> > +  system power without resuming system by DMA interrupts if AGCP DMA
> > +  does not request the IRQ.
> > +
> > +maintainers:
> > +  - Orson Zhai <orsonzhai@gmail.com>
> > +  - Baolin Wang <baolin.wang7@gmail.com>
> > +  - Chunyan Zhang <zhang.lyra@gmail.com>
> > +
> > +properties:
> > +  compatible:
> > +    const: sprd,sc9860-dma
> > +
> > +  reg:
> > +    maxItems: 1
> > +
> > +  interrupts:
> > +    maxItems: 1
> > +
> > +  clocks:
> > +    minItems: 1
> > +    maxItems: 2
> > +
> > +  clock-names:
> > +    oneOf:
> > +      - const: enable
> > +      # The ashb_eb clock is optional and only for AGCP DMA controller
> > +      - items:
> > +          - const: enable
> > +          - const: ashb_eb
> 
> This is better written as:
>   clock-names:
>     minItems: 1
>     items:
>       - const: enable
>       - const: ashb_eb

Ok, should I keep the comment?

> 
> > +
> > +  '#dma-cells':
> > +    const: 1
> > +
> > +  dma-channels:
> > +    const: 32
> > +
> > +  '#dma-channels':
> > +    const: 32
> > +    deprecated: true
> 
> If there are no users of this, I'd be inclined to just drop it from the
> binding.
> 
> Cheers,
> Conor.

It is specified in DT "For backwards compatibility", see e.g. [1]
I'm not sure if it's still required, I'm not very familiar with this platform.

[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/sprd/whale2.dtsi?h=v6.10-rc6#n124

Regards,
Stanislav