Re: [PATCH V3 1/5] dt-bindings: virtio: Add binding for virtio devices

[Rob Herring <robh+dt@kernel.org>]

On Sun, Jul 25, 2021 at 10:52 PM Viresh Kumar <viresh.kumar@linaro.org> wrote:
>
> Allow virtio device sub-nodes to be added to the virtio mmio or pci
> nodes. The compatible property for virtio device must be of format
> "virtio,<DID>", where DID is virtio device ID in hexadecimal format.
>
> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
> ---
>  .../devicetree/bindings/virtio/mmio.yaml      |  2 +-
>  .../bindings/virtio/virtio-device.yaml        | 47 +++++++++++++++++++
>  2 files changed, 48 insertions(+), 1 deletion(-)
>  create mode 100644 Documentation/devicetree/bindings/virtio/virtio-device.yaml
>
> diff --git a/Documentation/devicetree/bindings/virtio/mmio.yaml b/Documentation/devicetree/bindings/virtio/mmio.yaml
> index d46597028cf1..1b91553f87c6 100644
> --- a/Documentation/devicetree/bindings/virtio/mmio.yaml
> +++ b/Documentation/devicetree/bindings/virtio/mmio.yaml
> @@ -36,7 +36,7 @@ title: virtio memory mapped devices
>    - reg
>    - interrupts
>
> -additionalProperties: false
> +additionalProperties: true

That just allows for any random property. What you want is child nodes only:

addtionalProperties:
  type: object

Or you could reference virtio-device.yaml here.

>
>  examples:
>    - |
> diff --git a/Documentation/devicetree/bindings/virtio/virtio-device.yaml b/Documentation/devicetree/bindings/virtio/virtio-device.yaml
> new file mode 100644
> index 000000000000..15cb6df8c98a
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/virtio/virtio-device.yaml
> @@ -0,0 +1,47 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/virtio/virtio-device.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Virtio device bindings
> +
> +maintainers:
> +  - Viresh Kumar <viresh.kumar@linaro.org>
> +
> +description:
> +  These bindings are applicable to virtio devices irrespective of the bus they
> +  are bound to, like mmio or pci.
> +
> +# We need a select here so we don't match all nodes with 'virtio,mmio'
> +properties:
> +  $nodename:
> +    pattern: '^[a-z0-9]+-virtio(-[a-z0-9]+)?$'

Node names aren't based on the bus they are on, but their class.
You'll need to drop this.

> +    description: |
> +      Exactly one node describing the virtio device. The name of the node isn't
> +      significant but its phandle can be used to by a user of the virtio device.
> +
> +  compatible:
> +    pattern: "^virtio,[0-9a-f]+$"

DID is only 4 chars? If so, "^virtio,[0-9a-f]{1,4}$"

> +    description: Virtio device nodes.
> +      "virtio,DID", where DID is the virtio device id. The textual
> +      representation of DID shall be in lower case hexadecimal with leading
> +      zeroes suppressed.
> +
> +required:
> +  - compatible
> +
> +additionalProperties: true
> +
> +examples:
> +  - |
> +    virtio@3000 {
> +        compatible = "virtio,mmio";
> +        reg = <0x3000 0x100>;
> +        interrupts = <43>;
> +
> +        i2c-virtio {
> +            compatible = "virtio,22";
> +        };
> +    };
> +...
> --
> 2.31.1.272.g89b43f80a514
>