Re: [PATCH v4 2/2] dt-bindings: nand: meson: refine Amlogic NAND controller driver

[Miquel Raynal <miquel.raynal@bootlin.com>]

Hi Liang,

liang.yang@amlogic.com wrote on Sat, 2 Apr 2022 15:49:20 +0800:

> convert txt to yaml and refine the meson NFC clock document.

We generally prefer to split this into two changes (yaml conversion
then modifications). You need to be very explicit on the changes you
bring to this file afterward. Also you may s/refine/fix/ in your title
if this really is a correction of something that does not work at all as
you suggest.

Please mention that due to the other series about the clock changes
never being accepted the current binding was never valid/working
(again, I'm not sure it's the case on all Amlogic SoCs, so please be
very careful about that).

And please use a Link: tag to point to the discussion with Neil and
Jerome on your MMC/NAND subclock final discussion.

> Signed-off-by: Liang Yang <liang.yang@amlogic.com>
> ---
>  .../bindings/mtd/amlogic,meson-nand.txt       | 60 --------------
>  .../bindings/mtd/amlogic,meson-nand.yaml      | 80 +++++++++++++++++++
>  2 files changed, 80 insertions(+), 60 deletions(-)
>  delete mode 100644 Documentation/devicetree/bindings/mtd/amlogic,meson-nand.txt
>  create mode 100644 Documentation/devicetree/bindings/mtd/amlogic,meson-nand.yaml
> 
> diff --git a/Documentation/devicetree/bindings/mtd/amlogic,meson-nand.txt b/Documentation/devicetree/bindings/mtd/amlogic,meson-nand.txt
> deleted file mode 100644
> index 5794ab1147c1..000000000000
> --- a/Documentation/devicetree/bindings/mtd/amlogic,meson-nand.txt
> +++ /dev/null
> @@ -1,60 +0,0 @@
> -Amlogic NAND Flash Controller (NFC) for GXBB/GXL/AXG family SoCs
> -
> -This file documents the properties in addition to those available in
> -the MTD NAND bindings.
> -
> -Required properties:
> -- compatible : contains one of:
> -  - "amlogic,meson-gxl-nfc"
> -  - "amlogic,meson-axg-nfc"
> -- clocks     :
> -	A list of phandle + clock-specifier pairs for the clocks listed
> -	in clock-names.
> -
> -- clock-names: Should contain the following:
> -	"core" - NFC module gate clock
> -	"device" - device clock from eMMC sub clock controller
> -	"rx" - rx clock phase
> -	"tx" - tx clock phase
> -
> -- amlogic,mmc-syscon	: Required for NAND clocks, it's shared with SD/eMMC
> -				controller port C
> -
> -Optional children nodes:
> -Children nodes represent the available nand chips.
> -
> -Other properties:
> -see Documentation/devicetree/bindings/mtd/nand-controller.yaml for generic bindings.
> -
> -Example demonstrate on AXG SoC:
> -
> -	sd_emmc_c_clkc: mmc@7000 {
> -		compatible = "amlogic,meson-axg-mmc-clkc", "syscon";
> -		reg = <0x0 0x7000 0x0 0x800>;
> -	};
> -
> -	nand-controller@7800 {
> -		compatible = "amlogic,meson-axg-nfc";
> -		reg = <0x0 0x7800 0x0 0x100>;
> -		#address-cells = <1>;
> -		#size-cells = <0>;
> -		interrupts = <GIC_SPI 34 IRQ_TYPE_EDGE_RISING>;
> -
> -		clocks = <&clkc CLKID_SD_EMMC_C>,
> -			<&sd_emmc_c_clkc CLKID_MMC_DIV>,
> -			<&sd_emmc_c_clkc CLKID_MMC_PHASE_RX>,
> -			<&sd_emmc_c_clkc CLKID_MMC_PHASE_TX>;
> -		clock-names = "core", "device", "rx", "tx";
> -		amlogic,mmc-syscon = <&sd_emmc_c_clkc>;
> -
> -		pinctrl-names = "default";
> -		pinctrl-0 = <&nand_pins>;
> -
> -		nand@0 {
> -			reg = <0>;
> -			#address-cells = <1>;
> -			#size-cells = <1>;
> -
> -			nand-on-flash-bbt;
> -		};
> -	};
> diff --git a/Documentation/devicetree/bindings/mtd/amlogic,meson-nand.yaml b/Documentation/devicetree/bindings/mtd/amlogic,meson-nand.yaml
> new file mode 100644
> index 000000000000..965a2dd20645
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mtd/amlogic,meson-nand.yaml
> @@ -0,0 +1,80 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/mtd/amlogic,meson-nand.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Amlogic NAND Flash Controller (NFC) for GXBB/GXL/AXG family SoCs

Maybe you need to inherit from nand-controller.yaml.

> +
> +maintainers:
> +  - liang.yang@amlogic.com
> +
> +properties:
> +  compatible:
> +    enum:
> +      - "amlogic,meson-gxl-nfc"
> +      - "amlogic,meson-axg-nfc"
> +
> +  reg:
> +    maxItems: 2
> +
> +  '#address-cells':
> +    const: 1

Not sure this property is needed.

> +
> +  '#size-cells':
> +    const: 0

Ditto. Plus, this one looks wrong anyway.

> +
> +  reg-names:
> +    items:
> +      - const: nfc
> +      - const: emmc

Why do you need the emmc register map? Do you really need to perform a
register access there?

> +
> +  interrupts:
> +    maxItems: 1
> +
> +  clocks:
> +    maxItems: 2
> +
> +  clock-names:
> +    items:
> +      - const: core
> +      - const: device
> +
> +  "#clock-cells":
> +    const: 1

?

> +
> +required:
> +  - compatible
> +  - reg
> +  - '#address-cells'
> +  - '#size-cells'
> +  - reg-names
> +  - interrupts
> +  - clocks
> +  - clock-names
> +
> +additionalProperties: false

I will let Rob check that but I think what you need is

unevaluatedProperties: false

> +
> +examples:
> +  - |
> +    #include <dt-bindings/clock/axg-clkc.h>
> +    #include <dt-bindings/interrupt-controller/arm-gic.h>
> +    apb {
> +      #address-cells = <2>;
> +      #size-cells = <2>;

Not sure you need this upper node in the example.

> +      nand-controller@7800 {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +        compatible = "amlogic,meson-axg-nfc";
> +        reg = <0x0 0x7800 0x0 0x100>,
> +              <0x0 0x7000 0x0 0x800>;
> +        reg-names = "nfc", "emmc";
> +
> +        interrupts = <GIC_SPI 34 IRQ_TYPE_EDGE_RISING>;
> +        clocks = <&clkc CLKID_SD_EMMC_C>,
> +                 <&clkc CLKID_FCLK_DIV2>;
> +        clock-names = "core", "device";
> +
> +      };
> +    };
> +...


Thanks,
Miquèl