Re: [PATCH v2 2/4] spi: Add devicetree bindings documentation for Loongson SPI

[zhangqing <zhangqing@xxxxxxxxxxx>]

Hi Sergei Shtylyov,


On 12/08/2020 04:40 PM, Sergei Shtylyov wrote:
> Hello!
>
> On 08.12.2020 10:44, Qing Zhang wrote:
>
> > Add spi-ls7a binding documentation.
> >
> > Signed-off-by: Qing Zhang <zhangqing@xxxxxxxxxxx>
> > ---
> >   Documentation/devicetree/bindings/spi/spi-ls7a.txt | 31 
> > ++++++++++++++++++++++
> >   1 file changed, 31 insertions(+)
> >   create mode 100644 Documentation/devicetree/bindings/spi/spi-ls7a.txt
> >
> > diff --git a/Documentation/devicetree/bindings/spi/spi-ls7a.txt 
> > b/Documentation/devicetree/bindings/spi/spi-ls7a.txt
> > new file mode 100644
> > index 0000000..56247b5
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/spi/spi-ls7a.txt
> > @@ -0,0 +1,31 @@
> > +Binding for LOONGSON LS7A SPI controller
> > +
> > +Required properties:
> > +- compatible: should be 
> > "pci0014,7a0b.0","pci0014,7a0b","pciclass088000","pciclass0880".
> > +- reg: reference IEEE Std 1275-1994.
> > +- #address-cells: <1>, as required by generic SPI binding.
> > +- #size-cells: <0>, also as required by generic SPI binding.
> > +- #interrupts: No hardware interrupt.
>
>    You say it's a required prop, yet yuoe example doesn't have it...
        I want to emphasize here that LS7A SPI has no hardware 
interrupts, and DT is not actually used.
> > +
> > +Child nodes as per the generic SPI binding.
> > +
> > +Example:
> > +
> > +            spi@16,0 {
> > +                compatible = "pci0014,7a0b.0",
> > +                        "pci0014,7a0b",
> > +                        "pciclass088000",
> > +                        "pciclass0880";
> > +
> > +                #address-cells = <1>;
> > +                #size-cells = <0>;
> > +                reg = <0xb000 0x0 0x0 0x0 0x0>;
> > +                num-chipselects = <0>;
> > +                spiflash: s25fl016k@0 {
> > +                #address-cells = <1>;
> > +                #size-cells = <1>;
>
>    Once more?
>
> > +                compatible ="spansion,s25fl016k","jedec,spi-nor";
>
>    Once more?
>
> > + spi-max-frequency=<50000000>;
> > +                reg=<0>;
>
>    Once more? Did you mean this for a child node?
       Yes, these are child node attributes, the child node splash is 
not necessary.
> > +                };
> > +            };
     Thanks

     -Qing
> MBR, Sergei