Re: [LINUX PATCH v12 1/3] dt-bindings: mtd: arasan: Add device tree binding documentation

From: Boris Brezillon
Date: Fri Nov 09 2018 - 01:29:05 EST


On Fri, 9 Nov 2018 10:30:39 +0530
Naga Sureshkumar Relli <naga.sureshkumar.relli@xxxxxxxxxx> wrote:

> This patch adds the dts binding document for arasan nand flash controller
>
> Signed-off-by: Naga Sureshkumar Relli <naga.sureshkumar.relli@xxxxxxxxxx>
> ---
> Changes in v12:
> - Removed interrupt-parent description as it is implied as suggested by
> Rob Herring
> - Added missing ';' as required
> Changes in v11:
> - Updated compatible description as suggested by Boris
> - Removed arasan-has-dma property
> Changes in v10:
> - None
> Changes in v9:
> - None
> Changes in v8:
> - Updated compatible and clock-names as per Boris comments
> Changes in v7:
> - Corrected the acronyms those should be in caps
> Changes in v6:
> - Removed num-cs property
> - Separated nandchip from nand controller
> Changes in v5:
> - None
> Changes in v4:
> - Added num-cs property
> - Added clock support
> Changes in v3:
> - None
> Changes in v2:
> - None
> ---
> .../devicetree/bindings/mtd/arasan_nand.txt | 32 ++++++++++++++++++++++
> 1 file changed, 32 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/mtd/arasan_nand.txt
>
> diff --git a/Documentation/devicetree/bindings/mtd/arasan_nand.txt b/Documentation/devicetree/bindings/mtd/arasan_nand.txt
> new file mode 100644
> index 0000000..b522daf
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mtd/arasan_nand.txt
> @@ -0,0 +1,32 @@
> +Arasan NAND Flash Controller with ONFI 3.1 support
> +
> +Required properties:
> +- compatible: Should be "xlnx,zynqmp-nand", "arasan,nfc-v3p10"
> +- reg: Memory map for module access
> +- interrupts: Should contain the interrupt for the device
> +- clock-name: List of input clocks - "sys", "flash"
> + (See clock bindings for details)
> +- clocks: Clock phandles (see clock bindings for details)
> +
> +Required properties for child node:
> +- nand-ecc-mode: see nand.txt

Why is it required? Can't you fallback to HW when this prop is missing?
Oh, and reg is not listed in the required props.

> +
> +For NAND partition information please refer the below file
> +Documentation/devicetree/bindings/mtd/partition.txt
> +
> +Example:
> + nfc: nand@ff100000 {
> + compatible = "xlnx,zynqmp-nand", "arasan,nfc-v3p10";
> + reg = <0x0 0xff100000 0x1000>;
> + clock-name = "sys", "flash";
> + clocks = <&misc_clk &misc_clk>;
> + interrupt-parent = <&gic>;
> + interrupts = <0 14 4>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + nand@0 {
> + reg = <0>;
> + nand-ecc-mode = "hw";
> + };
> + };