On Thu, Jan 30, 2020 at 02:27:27PM +0900, Kunihiko Hayashi wrote: > Add devicetree binding documentation for external DMA controller > implemented on Socionext UniPhier SoCs. > > Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@xxxxxxxxxxxxx> > --- > .../bindings/dma/socionext,uniphier-xdmac.yaml | 57 ++++++++++++++++++++++ > 1 file changed, 57 insertions(+) > create mode 100644 Documentation/devicetree/bindings/dma/socionext,uniphier-xdmac.yaml > > diff --git a/Documentation/devicetree/bindings/dma/socionext,uniphier-xdmac.yaml b/Documentation/devicetree/bindings/dma/socionext,uniphier-xdmac.yaml > new file mode 100644 > index 00000000..32abf18 > --- /dev/null > +++ b/Documentation/devicetree/bindings/dma/socionext,uniphier-xdmac.yaml > @@ -0,0 +1,57 @@ > +# SPDX-License-Identifier: GPL-2.0 Dual license new bindings: (GPL-2.0-only OR BSD-2-Clause) > +%YAML 1.2 > +--- > +$id: http://devicetree.org/schemas/dma/socionext,uniphier-xdmac.yaml# > +$schema: http://devicetree.org/meta-schemas/core.yaml# > + > +title: Socionext UniPhier external DMA controller > + > +description: | > + This describes the devicetree bindings for an external DMA engine to perform > + memory-to-memory or peripheral-to-memory data transfer capable of supporting > + 16 channels, implemented in Socionext UniPhier SoCs. > + > +maintainers: > + - Kunihiko Hayashi <hayashi.kunihiko@xxxxxxxxxxxxx> > + > +allOf: > + - $ref: "dma-controller.yaml#" > + > +properties: > + compatible: > + items: > + - const: socionext,uniphier-xdmac You can drop 'items' for a single item. > + > + reg: > + minItems: 1 > + maxItems: 2 You need to say what each entry is: items: - description: ... - description: ... > + > + interrupts: > + maxItems: 1 > + > + "#dma-cells": > + const: 2 > + description: | > + DMA request from clients consists of 2 cells: > + 1. Channel index > + 2. Transfer request factor number, If no transfer factor, use 0. > + The number is SoC-specific, and this should be specified with > + relation to the device to use the DMA controller. > + > +required: > + - compatible > + - reg > + - interrupts > + - "#dma-cells" Add: additionalProperties: false > + > +examples: > + - | > + xdmac: dma-controller@5fc10000 { > + compatible = "socionext,uniphier-xdmac"; > + reg = <0x5fc10000 0x1000>, <0x5fc20000 0x800>; > + interrupts = <0 188 4>; > + #dma-cells = <2>; > + dma-channels = <16>; Not documented. You need at least 'dma-channels: true' to indicate you're using this. But you should be able to have some constraints such as 'maximum: 16'. Rob