Re: [PATCH v4 3/6] tegra: fdt: Add NAND controller binding and definitions

[Scott Wood <scottwood@freescale.com>]

On 07/30/2012 01:53 AM, Simon Glass wrote:
> diff --git a/arch/arm/dts/tegra20.dtsi b/arch/arm/dts/tegra20.dtsi
> index f95be58..d936b1e 100644
> --- a/arch/arm/dts/tegra20.dtsi
> +++ b/arch/arm/dts/tegra20.dtsi
> @@ -204,4 +204,11 @@
>  		compatible = "nvidia,tegra20-kbc";
>  		reg = <0x7000e200 0x0078>;
>  	};
> +
> +	nand: nand-controller@70008000 {
> +		#address-cells = <1>;
> +		#size-cells = <0>;
> +		compatible = "nvidia,tegra20-nand";
> +		reg = <0x70008000 0x100>;
> +	};
>  };
> diff --git a/doc/device-tree-bindings/nand/nvidia,tegra20-nand.txt b/doc/device-tree-bindings/nand/nvidia,tegra20-nand.txt
> new file mode 100644
> index 0000000..86ae408
> --- /dev/null
> +++ b/doc/device-tree-bindings/nand/nvidia,tegra20-nand.txt
> @@ -0,0 +1,53 @@
> +NAND Flash
> +----------
> +
> +(there isn't yet a generic binding in Linux, so this describes what is in
> +U-Boot. There should not be Linux-specific or U-Boot specific binding, just
> +a binding that describes this hardware. But agreeing a binding in Linux in
> +the absence of a driver may be beyond my powers.)

Please at least attempt to get a binding accepted in Linux, or perhaps
in a neutral repository such as devicetree.org (but point out on
devicetree-discuss that you've posted it there).  The device tree is
supposed to describe the hardware, not what Linux currently uses.

> +Example
> +-------
> +
> +nand-controller@0x70008000 {
> +	compatible = "nvidia,tegra20-nand";
> +	#address-cells = <1>;
> +	#size-cells = <0>;
> +	nvidia,wp-gpios = <&gpio 59 0>;		/* PH3 */
> +	nvidia,nand-width = <8>;
> +	nvidia,timing = <26 100 20 80 20 10 12 10 70>;
> +	nand@0 {
> +		reg = <0>;
> +		compatible = "hynix,hy27uf4g2b", "nand-flash";
> +	};
> +};

Where is "reg" in the parent node?  You're not supposed to have a unit
address without reg.   Also, most bus bindings don't put 0x in the unit
address).

I see that it's OK in the actual .dtsi -- it's just the example that
needs fixing.

-Scott