Re: [PATCH v4 2/5] media: dt-bindings: media: renesas,drif: Convert to json-schema

[Rob Herring <robh@kernel.org>]

On Wed, Oct 14, 2020 at 04:57:16PM +0100, Fabrizio Castro wrote:
> Convert the Renesas DRIF bindings to DT schema and update
> MAINTAINERS accordingly.
> 
> Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
> ---
> v3->v4:
> * Replace "if" statement with "else" statement for the branch
>   rejecting pinctrl-0 and pinctrl-names properties, as suggested
>   by Geert
> v2->v3:
> * Removed the definition of pinctrl-0 and pinctrl-names, as
>   suggested by Geert
> * Added "power-domains" to the list of required properties,
>   as suggested by Geert
> v1->v2:
> * s/controller/Controller/ in the title of renesas,drif.yaml
>   as suggested by Laurent.
> 
>  .../bindings/media/renesas,drif.txt           | 177 -----------
>  .../bindings/media/renesas,drif.yaml          | 277 ++++++++++++++++++
>  MAINTAINERS                                   |   2 +-
>  3 files changed, 278 insertions(+), 178 deletions(-)
>  delete mode 100644 Documentation/devicetree/bindings/media/renesas,drif.txt
>  create mode 100644 Documentation/devicetree/bindings/media/renesas,drif.yaml
> 
> diff --git a/Documentation/devicetree/bindings/media/renesas,drif.txt b/Documentation/devicetree/bindings/media/renesas,drif.txt
> deleted file mode 100644
> index 0d8974aa8b38..000000000000
> --- a/Documentation/devicetree/bindings/media/renesas,drif.txt
> +++ /dev/null
> @@ -1,177 +0,0 @@
> -Renesas R-Car Gen3 Digital Radio Interface controller (DRIF)
> -------------------------------------------------------------
> -
> -R-Car Gen3 DRIF is a SPI like receive only slave device. A general
> -representation of DRIF interfacing with a master device is shown below.
> -
> -+---------------------+                +---------------------+
> -|                     |-----SCK------->|CLK                  |
> -|       Master        |-----SS-------->|SYNC  DRIFn (slave)  |
> -|                     |-----SD0------->|D0                   |
> -|                     |-----SD1------->|D1                   |
> -+---------------------+                +---------------------+
> -
> -As per datasheet, each DRIF channel (drifn) is made up of two internal
> -channels (drifn0 & drifn1). These two internal channels share the common
> -CLK & SYNC. Each internal channel has its own dedicated resources like
> -irq, dma channels, address space & clock. This internal split is not
> -visible to the external master device.
> -
> -The device tree model represents each internal channel as a separate node.
> -The internal channels sharing the CLK & SYNC are tied together by their
> -phandles using a property called "renesas,bonding". For the rest of
> -the documentation, unless explicitly stated, the word channel implies an
> -internal channel.
> -
> -When both internal channels are enabled they need to be managed together
> -as one (i.e.) they cannot operate alone as independent devices. Out of the
> -two, one of them needs to act as a primary device that accepts common
> -properties of both the internal channels. This channel is identified by a
> -property called "renesas,primary-bond".
> -
> -To summarize,
> -   - When both the internal channels that are bonded together are enabled,
> -     the zeroth channel is selected as primary-bond. This channels accepts
> -     properties common to all the members of the bond.
> -   - When only one of the bonded channels need to be enabled, the property
> -     "renesas,bonding" or "renesas,primary-bond" will have no effect. That
> -     enabled channel can act alone as any other independent device.
> -
> -Required properties of an internal channel:
> --------------------------------------------
> -- compatible:	"renesas,r8a7795-drif" if DRIF controller is a part of R8A7795 SoC.
> -		"renesas,r8a7796-drif" if DRIF controller is a part of R8A7796 SoC.
> -		"renesas,rcar-gen3-drif" for a generic R-Car Gen3 compatible device.
> -
> -		When compatible with the generic version, nodes must list the
> -		SoC-specific version corresponding to the platform first
> -		followed by the generic version.
> -
> -- reg: offset and length of that channel.
> -- interrupts: associated with that channel.
> -- clocks: phandle and clock specifier of that channel.
> -- clock-names: clock input name string: "fck".
> -- dmas: phandles to the DMA channels.
> -- dma-names: names of the DMA channel: "rx".
> -- renesas,bonding: phandle to the other channel.
> -
> -Optional properties of an internal channel:
> --------------------------------------------
> -- power-domains: phandle to the respective power domain.
> -
> -Required properties of an internal channel when:
> -	- It is the only enabled channel of the bond (or)
> -	- If it acts as primary among enabled bonds
> ---------------------------------------------------------
> -- pinctrl-0: pin control group to be used for this channel.
> -- pinctrl-names: must be "default".
> -- renesas,primary-bond: empty property indicating the channel acts as primary
> -			among the bonded channels.
> -- port: child port node corresponding to the data input, in accordance with
> -	the video interface bindings defined in
> -	Documentation/devicetree/bindings/media/video-interfaces.txt. The port
> -	node must contain at least one endpoint.
> -
> -Optional endpoint property:
> ----------------------------
> -- sync-active: Indicates sync signal polarity, 0/1 for low/high respectively.
> -	       This property maps to SYNCAC bit in the hardware manual. The
> -	       default is 1 (active high).
> -
> -Example:
> ---------
> -
> -(1) Both internal channels enabled:
> ------------------------------------
> -
> -When interfacing with a third party tuner device with two data pins as shown
> -below.
> -
> -+---------------------+                +---------------------+
> -|                     |-----SCK------->|CLK                  |
> -|       Master        |-----SS-------->|SYNC  DRIFn (slave)  |
> -|                     |-----SD0------->|D0                   |
> -|                     |-----SD1------->|D1                   |
> -+---------------------+                +---------------------+
> -
> -	drif00: rif@e6f40000 {
> -		compatible = "renesas,r8a7795-drif",
> -			     "renesas,rcar-gen3-drif";
> -		reg = <0 0xe6f40000 0 0x64>;
> -		interrupts = <GIC_SPI 12 IRQ_TYPE_LEVEL_HIGH>;
> -		clocks = <&cpg CPG_MOD 515>;
> -		clock-names = "fck";
> -		dmas = <&dmac1 0x20>, <&dmac2 0x20>;
> -		dma-names = "rx", "rx";
> -		power-domains = <&sysc R8A7795_PD_ALWAYS_ON>;
> -		renesas,bonding = <&drif01>;
> -		renesas,primary-bond;
> -		pinctrl-0 = <&drif0_pins>;
> -		pinctrl-names = "default";
> -		port {
> -			drif0_ep: endpoint {
> -			     remote-endpoint = <&tuner_ep>;
> -			};
> -		};
> -	};
> -
> -	drif01: rif@e6f50000 {
> -		compatible = "renesas,r8a7795-drif",
> -			     "renesas,rcar-gen3-drif";
> -		reg = <0 0xe6f50000 0 0x64>;
> -		interrupts = <GIC_SPI 13 IRQ_TYPE_LEVEL_HIGH>;
> -		clocks = <&cpg CPG_MOD 514>;
> -		clock-names = "fck";
> -		dmas = <&dmac1 0x22>, <&dmac2 0x22>;
> -		dma-names = "rx", "rx";
> -		power-domains = <&sysc R8A7795_PD_ALWAYS_ON>;
> -		renesas,bonding = <&drif00>;
> -	};
> -
> -
> -(2) Internal channel 1 alone is enabled:
> -----------------------------------------
> -
> -When interfacing with a third party tuner device with one data pin as shown
> -below.
> -
> -+---------------------+                +---------------------+
> -|                     |-----SCK------->|CLK                  |
> -|       Master        |-----SS-------->|SYNC  DRIFn (slave)  |
> -|                     |                |D0 (unused)          |
> -|                     |-----SD-------->|D1                   |
> -+---------------------+                +---------------------+
> -
> -	drif00: rif@e6f40000 {
> -		compatible = "renesas,r8a7795-drif",
> -			     "renesas,rcar-gen3-drif";
> -		reg = <0 0xe6f40000 0 0x64>;
> -		interrupts = <GIC_SPI 12 IRQ_TYPE_LEVEL_HIGH>;
> -		clocks = <&cpg CPG_MOD 515>;
> -		clock-names = "fck";
> -		dmas = <&dmac1 0x20>, <&dmac2 0x20>;
> -		dma-names = "rx", "rx";
> -		power-domains = <&sysc R8A7795_PD_ALWAYS_ON>;
> -		renesas,bonding = <&drif01>;
> -	};
> -
> -	drif01: rif@e6f50000 {
> -		compatible = "renesas,r8a7795-drif",
> -			     "renesas,rcar-gen3-drif";
> -		reg = <0 0xe6f50000 0 0x64>;
> -		interrupts = <GIC_SPI 13 IRQ_TYPE_LEVEL_HIGH>;
> -		clocks = <&cpg CPG_MOD 514>;
> -		clock-names = "fck";
> -		dmas = <&dmac1 0x22>, <&dmac2 0x22>;
> -		dma-names = "rx", "rx";
> -		power-domains = <&sysc R8A7795_PD_ALWAYS_ON>;
> -		renesas,bonding = <&drif00>;
> -		pinctrl-0 = <&drif0_pins>;
> -		pinctrl-names = "default";
> -		port {
> -			drif0_ep: endpoint {
> -			     remote-endpoint = <&tuner_ep>;
> -			     sync-active = <0>;
> -			};
> -		};
> -	};
> diff --git a/Documentation/devicetree/bindings/media/renesas,drif.yaml b/Documentation/devicetree/bindings/media/renesas,drif.yaml
> new file mode 100644
> index 000000000000..3832ce837553
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/media/renesas,drif.yaml
> @@ -0,0 +1,277 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/media/renesas,drif.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Renesas R-Car Gen3 Digital Radio Interface Controller (DRIF)
> +
> +maintainers:
> +  - Ramesh Shanmugasundaram <rashanmu@gmail.com>
> +  - Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> +
> +description: |
> +  R-Car Gen3 DRIF is a SPI like receive only slave device. A general
> +  representation of DRIF interfacing with a master device is shown below.
> +
> +  +---------------------+                +---------------------+
> +  |                     |-----SCK------->|CLK                  |
> +  |       Master        |-----SS-------->|SYNC  DRIFn (slave)  |
> +  |                     |-----SD0------->|D0                   |
> +  |                     |-----SD1------->|D1                   |
> +  +---------------------+                +---------------------+
> +
> +  As per datasheet, each DRIF channel (drifn) is made up of two internal
> +  channels (drifn0 & drifn1). These two internal channels share the common
> +  CLK & SYNC. Each internal channel has its own dedicated resources like
> +  irq, dma channels, address space & clock. This internal split is not
> +  visible to the external master device.
> +
> +  The device tree model represents each internal channel as a separate node.
> +  The internal channels sharing the CLK & SYNC are tied together by their
> +  phandles using a property called "renesas,bonding". For the rest of
> +  the documentation, unless explicitly stated, the word channel implies an
> +  internal channel.
> +
> +  When both internal channels are enabled they need to be managed together
> +  as one (i.e.) they cannot operate alone as independent devices. Out of the
> +  two, one of them needs to act as a primary device that accepts common
> +  properties of both the internal channels. This channel is identified by a
> +  property called "renesas,primary-bond".
> +
> +  To summarize,
> +     * When both the internal channels that are bonded together are enabled,
> +       the zeroth channel is selected as primary-bond. This channels accepts
> +       properties common to all the members of the bond.
> +     * When only one of the bonded channels need to be enabled, the property
> +       "renesas,bonding" or "renesas,primary-bond" will have no effect. That
> +       enabled channel can act alone as any other independent device.
> +
> +properties:
> +  compatible:
> +    items:
> +      - enum:
> +        - renesas,r8a7795-drif        # R-Car H3
> +        - renesas,r8a7796-drif        # R-Car M3-W

Note the bot error is from yamllint which just got added to the checks. 
Need 2 more spaces indent here.

With that,

Reviewed-by: Rob Herring <robh@kernel.org>