RE: [PATCH 1/4] dt-bindings: fsl: scu: add ocotp binding

From: Aisheng Dong
Date: Mon May 06 2019 - 04:07:33 EST


> From: Peng Fan
> Sent: Sunday, May 5, 2019 9:28 PM
>
> NXP i.MX8QXP is an ARMv8 SoC with a Cortex-M4 core inside as system
> controller(SCU), the ocotp controller is being controlled by the SCU, so Linux
> need use RPC to SCU for ocotp handling. This patch adds binding doc for i.MX8
> SCU OCOTP driver.
>
> Signed-off-by: Peng Fan <peng.fan@xxxxxxx>
> Cc: Rob Herring <robh+dt@xxxxxxxxxx>
> Cc: Mark Rutland <mark.rutland@xxxxxxx>
> Cc: Aisheng Dong <aisheng.dong@xxxxxxx>
> Cc: Shawn Guo <shawnguo@xxxxxxxxxx>
> Cc: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
> Cc: Stephen Boyd <sboyd@xxxxxxxxxx>
> Cc: Anson Huang <anson.huang@xxxxxxx>
> Cc: devicetree@xxxxxxxxxxxxxxx
> ---
> Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt | 13
> +++++++++++++
> 1 file changed, 13 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> index 5d7dbabbb784..9cb7d52bdf26 100644
> --- a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> +++ b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> @@ -100,6 +100,13 @@ ID in its "clocks" phandle cell.
> See the full list of clock IDs from:
> include/dt-bindings/clock/imx8qxp-clock.h
>
> +OCOTP bindings based on SCU Message Protocol
> +------------------------------------------------------------
> +Required properties:
> +- compatible: Should be "fsl,imx8qxp-ocotp"
> +- #address-cells: Must be 1. Contains byte index
> +- #size-cells: Must be 1. Contains byte length
> +

Please put this unimportant one to the last.
And it's better to mention the optional child nodes for data cells as
Above #address-cells and #size-cells are used for it.
Just like:
Documentation/devicetree/bindings/nvmem/imx-ocotp.txt

> Pinctrl bindings based on SCU Message Protocol
> ------------------------------------------------------------
>
> @@ -177,6 +184,12 @@ firmware {
> ...
> };
>
> + ocotp: imx8qx-ocotp {
> + #address-cells = <1>;
> + #size-cells = <1>;

Not sure if it's a free choice, but AFAIK we usually write #address-cells and #size-cells
under compatible string according to the example in DT spec and doc.
https://elinux.org/Device_Tree_Usage
https://github.com/devicetree-org/devicetree-specification/releases/tag/v0.2

Maybe Rob can comment to avoid confusing.

Otherwise, this patch seems good to me.

Regards
Dong Aisheng

> + compatible = "fsl,imx8qxp-ocotp";
> + };
> +
> pd: imx8qx-pd {
> compatible = "fsl,imx8qxp-scu-pd", "fsl,scu-pd";
> #power-domain-cells = <1>;
> --
> 2.16.4