Re: [PATCH 1/2 v2] dt-bindings: Create DT bindings for [PS]ATA controllers

[Rob Herring <robh@kernel.org>]

On Mon, Jan 06, 2020 at 02:42:23AM +0100, Linus Walleij wrote:
> I need to create subnodes for drives connected to PATA
> or SATA host controllers, and this needs to be supported
> generally, so create a common YAML binding for
> "ide" or "sata" that will support subnodes with ports.
> 
> This has been designed as a subset of
> ata/pata-sata-common.yaml with the bare essentials and
> should be possible to extend or superset to cover the
> common bindings.
> 
> Cc: Rob Herring <robh+dt@kernel.org>
> Cc: devicetree@vger.kernel.org
> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
> ---
> ChangeLog v1->v2:
> - Use ide@ and sata@ as node names.
> - Use ide-port@ and sata-port@ for the ports toward the
>   drives, rather than letting the subnodes be the drives
>   themselves.
> ---
>  .../bindings/ata/pata-sata-common.yaml        | 51 +++++++++++++++++++
>  1 file changed, 51 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/ata/pata-sata-common.yaml
> 
> diff --git a/Documentation/devicetree/bindings/ata/pata-sata-common.yaml b/Documentation/devicetree/bindings/ata/pata-sata-common.yaml
> new file mode 100644
> index 000000000000..f46f04446607
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/ata/pata-sata-common.yaml
> @@ -0,0 +1,51 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/ata/pata-sata-common.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Common Properties for Parallel and Serial AT attachment controllers
> +
> +maintainers:
> +  - Linus Walleij <linus.walleij@linaro.org>
> +
> +description: |
> +  This document defines device tree properties common to most Parallel
> +  (PATA, also known as IDE) and Serial (SATA) AT attachment storage devices.
> +  It doesn't constitue a device tree binding specification by itself but is
> +  meant to be referenced by device tree bindings.
> +
> +  The PATA/SATA controller device tree bindings are responsible for
> +  defining whether each property is required or optional.
> +
> +properties:
> +  $nodename:
> +    pattern: "^(ide|sata)(@.*)?$"
> +    description:
> +      Specifies the host controller node. PATA host controller nodes are named
> +      "ide" and SATA controller nodes are named "sata"
> +
> +  "#address-cells":
> +    const: 1
> +
> +  "#size-cells":
> +    const: 0
> +
> +patternProperties:
> +  "^(ide|sata)-port@[0-1]$":

This would allow ide@... to have sata-port@... as a child node.

> +    description: |
> +      DT nodes for ports connected on the PATA or SATA host. The master drive
> +      will have ID number 0 and the slave drive will have ID number 1.
> +      The PATA port nodes will be named "ide-port" and the SATA port nodes will
> +      be named "sata-port".
> +    type: object
> +
> +    properties:
> +      reg:
> +        minimum: 0
> +        maximum: 1

For SATA, we can have more than 2.

Given both of the above, probably this should be split into 2 files.

Rob