Re: [PATCH v2 06/10] media: dt-bindings: Document SAMA5D4 VDEC bindings

[Emil Velikov <emil.l.velikov@gmail.com>]

On Wed, 24 Mar 2021 at 15:17, Rob Herring <robh@kernel.org> wrote:
>
> On Thu, Mar 11, 2021 at 03:40:51PM +0000, Emil Velikov wrote:
> > From: Emil Velikov <emil.velikov@collabora.com>
> >
> > Add devicetree binding documentation for the Hantro G1/G2 VDEC on
> > the Microchip SAMAS5D4 SoC.
> >
> > Cc: Rob Herring <robh+dt@kernel.org>
> > Cc: Frank Rowand <frowand.list@gmail.com>
> > Cc: devicetree@vger.kernel.org>
> > Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
> > ---
> > v2
> >  - Newly introduced
> >  - s/Atmel/Microchip/ (Nicolas)
> >  - Drop leading 0 in node name/address
> > ---
> >  .../media/microchip,sama5d4-vdec.yaml         | 59 +++++++++++++++++++
> >  1 file changed, 59 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/media/microchip,sama5d4-vdec.yaml
> >
> > diff --git a/Documentation/devicetree/bindings/media/microchip,sama5d4-vdec.yaml b/Documentation/devicetree/bindings/media/microchip,sama5d4-vdec.yaml
> > new file mode 100644
> > index 000000000000..9cb2c0295d54
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/media/microchip,sama5d4-vdec.yaml
> > @@ -0,0 +1,59 @@
> > +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> > +
> > +%YAML 1.2
> > +---
> > +$id: "http://devicetree.org/schemas/media/microchip,sama5d4-vdec.yaml#"
> > +$schema: "http://devicetree.org/meta-schemas/core.yaml#"
> > +
> > +title: Hantro G1 VPU codec implemented on Microchip SAMA5D4 SoCs
> > +
> > +maintainers:
> > +  - Emil Velikov <emil.velikov@collabora.com>
> > +
> > +description:
> > +  Hantro G1 video decode accelerator present on Microchip SAMA5D4 SoCs.
> > +
> > +properties:
> > +  compatible:
> > +    const: microchip,sama5d4-vdec
> > +
> > +  reg:
> > +    maxItems: 1
> > +
> > +  interrupts:
> > +    maxItems: 1
> > +
> > +  interrupt-names:
> > +    items:
> > +      - const: vdec
>
> Why do you need a name? *-names are used to distinguish multiple entries
> and don't add anything if only a single entry.
>
On one hand the names are used to describe the hardware - the SAMA
board uses designated clock and interrupt lines - both called "vdec".
Additionally the names are ultimately required by the underlying API -
platform_get_irq_byname and  devm_clk_bulk_get respectively.
How can we get the respective entries without the name?

Skimming through the existing dts file -
arch/arm/boot/dts/sama5d4.dtsi and other dts files - there are lots of
examples where the device tree binding contains the name for a single
clock/interrupt.

Thanks
Emil