From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
To: Jacob Chen <jacob-chen@iotwrt.com>
Cc: linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org,
        heiko@sntech.de, robh+dt@kernel.org, mchehab@kernel.org,
        linux-media@vger.kernel.org, laurent.pinchart+renesas@ideasonboard.com,
        hans.verkuil@cisco.com, s.nawrocki@samsung.com, tfiga@chromium.org,
        nicolas@ndufresne.ca, Yakir Yang <ykk@rock-chips.com>
Subject: Re: [PATCH v2 6/6] dt-bindings: Document the Rockchip RGA bindings
Date: Sat, 15 Jul 2017 12:23:12 +0300
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Hi Jacob,

Thank you for the patch.

On Saturday 15 Jul 2017 14:58:40 Jacob Chen wrote:
> Add DT bindings documentation for Rockchip RGA
> 
> Signed-off-by: Yakir Yang <ykk@rock-chips.com>
> Signed-off-by: Jacob Chen <jacob-chen@iotwrt.com>
> ---
>  .../devicetree/bindings/media/rockchip-rga.txt     | 35 +++++++++++++++++++
>  1 file changed, 35 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/media/rockchip-rga.txt
> 
> diff --git a/Documentation/devicetree/bindings/media/rockchip-rga.txt
> b/Documentation/devicetree/bindings/media/rockchip-rga.txt new file mode
> 100644
> index 0000000..966eba0
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/media/rockchip-rga.txt
> @@ -0,0 +1,35 @@
> +device-tree bindings for rockchip 2D raster graphic acceleration controller
> (RGA)
> +
> +RGA is a separate 2D raster graphic acceleration unit. It accelerates 2D

"Separate" from what ? Do you mean "standalone" ?

> +graphics operations, such as point/line drawing, image scaling, rotation,
> +BitBLT, alpha blending and image blur/sharpness.
> +
> +Required properties:
> +- compatible: value should be one of the following
> +		"rockchip,rk3228-rga";
> +		"rockchip,rk3288-rga";
> +		"rockchip,rk3399-rga";

The driver in patch 2/6 has match entry for rk3328, which is missing from this 
list.

As the implementation of the driver doesn't seem to discriminate between the 
four SoCs, wouldn't it make sense to create a generic compatible string on 
which the driver would match ? You can have both the generic and SoC-specific 
compatible strings in DT if there are differences between the IP core in those 
SoCs that might need to be handled later by the driver.

> +- interrupts: RGA interrupt number.

This is an "interrupt specifier", not just an "interrupt number" (as you can 
see in the example below there are three numbers)

> +
> +- clocks: phandle to RGA sclk/hclk/aclk clocks
> +
> +- clock-names: should be "aclk" "hclk" and "sclk"

Nitpicking, there should be a comma after "aclk".

> +
> +- resets: Must contain an entry for each entry in reset-names.
> +  See ../reset/reset.txt for details.
> +- reset-names: should be "core" "axi" and "ahb"

And a comma after "core".

> +
> +Example:
> +SoC specific DT entry:

s/SoC specific/SoC-specific/

> +	rga: rga@ff680000 {
> +		compatible = "rockchip,rk3399-rga";
> +		reg = <0xff680000 0x10000>;
> +		interrupts = <GIC_SPI 55 IRQ_TYPE_LEVEL_HIGH>;
> +		interrupt-names = "rga";

The interrupt-names property is not described above. Do you really need it ?

> +		clocks = <&cru ACLK_RGA>, <&cru HCLK_RGA>, <&cru 
SCLK_RGA_CORE>;
> +		clock-names = "aclk", "hclk", "sclk";
> +
> +		resets = <&cru SRST_RGA_CORE>, <&cru SRST_A_RGA>, <&cru 
SRST_H_RGA>;
> +		reset-names = "core, "axi", "ahb";
> +	};

-- 
Regards,

Laurent Pinchart