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

Michal Simek
2018-11-16T12:34:27Z

On 16. 11. 18 12:50, Martin Lund wrote:
> Hi Naga,
>
> I've been working on running up the latest kernel (v4.20-rc2) on our
> custom Xilinx hw board so that I can test the v12 version of your
> Arasan nand driver.
>
> I've managed to get the driver successfully up and running and ready
> for testing with a Micron MT29F64G08AFAAAWP device. However, setting
> it up I've found a few inaccuracies in the documentation of the device
> tree bindings.
>
> This is the device configuration that ended up working for me with
> linux v4.20-rc2:
>
> nfc: nand@ff100000 {
> compatible = "xlnx,zynqmp-nand", "arasan,nfc-v3p10";
> reg = <0x0 0xff100000 0x0 0x1000>;
> clock-names = "clk_sys", "clk_flash";
> clocks = <&clk200>, <&clk100>;
> interrupt-parent = <&gic>;
> interrupts = <0 14 4>;
> #address-cells = <1>;
> #size-cells = <0>;
>
> nand@0 {
> reg = <0>;
> nand-ecc-mode = "hw";
> };
> };
>
> Compared with the example you will notice that "clock-name" should be
> "clock-names". reg was missing a "0x0".

clock-names and even that names - you are right it is not correct and
should be fixed.

Missing 0x0 in reg doesn't matter because it depends on address/size cells.

> I think it is helpful to provide a real-world working example, so you
> might also consider changing the example "clocks" configuration to
> clk200/clk100 since there is no clk_misc among the clock sources of
> any of the xilinx zynqmp board device tree configurations.

Real example is the best normally just c&p from existing dts is the way
to go.
But in connection to clocks it doesn't matter what exactly should be
there and I don't think there is any consistency in that. Hopefully this
will be removed by yaml conversion.

Thanks,
Michal