[PATCH v3 4/5] mtd: spi-nor: bindings for the Aspeed memory controllers

[Joel Stanley]

On Sat, Dec 10, 2016 at 3:49 AM, Cédric Le Goater <clg at kaod.org> wrote:
> Signed-off-by: Cédric Le Goater <clg at kaod.org>
> ---
>  .../devicetree/bindings/mtd/aspeed-smc.txt         | 51 ++++++++++++++++++++++
>  1 file changed, 51 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/mtd/aspeed-smc.txt
>
> diff --git a/Documentation/devicetree/bindings/mtd/aspeed-smc.txt b/Documentation/devicetree/bindings/mtd/aspeed-smc.txt
> new file mode 100644
> index 000000000000..e2c88cea38f6
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mtd/aspeed-smc.txt
> @@ -0,0 +1,51 @@
> +* Aspeed Firmware Memory controller
> +* Aspeed SPI Flash Memory Controller
> +
> +The Firmware Memory Controller in the Aspeed AST2500 SoC supports
> +three chip selects, two of which are always of SPI type and the third
> +can be SPI or NOR type flash, but the driver only supports SPI.

As the bindings are a description of the hardware and not the driver,
we might want to reword this. Perhaps "these bindings only describe
SPI"?

Cheers,

Joel

> +
> +The two SPI flash memory controllers in the AST2500 each support two
> +chip selects.
> +
> +Required properties:
> +  - compatible : Should be one of
> +       "aspeed,ast2400-fmc" for the AST2400 Firmware Memory Controller
> +       "aspeed,ast2400-spi" for the AST2400 SPI Flash memory Controller
> +       "aspeed,ast2500-fmc" for the AST2500 Firmware Memory Controller
> +       "aspeed,ast2500-spi" for the AST2500 SPI flash memory controllers
> +
> +  - reg : the first contains the control register location and length,
> +          the second contains the memory window mapping address and length
> +  - #address-cells : must be 1 corresponding to chip select child binding
> +  - #size-cells : must be 0 corresponding to chip select child binding
> +
> +Optional properties:
> +  - interrupts : Should contain the interrupt for the dma device if an
> +    FMC
> +
> +The child nodes are the SPI flash modules which must have a compatible
> +property as specified in bindings/mtd/jedec,spi-nor.txt
> +
> +Optionally, the child node can contain properties for SPI mode (may be
> +ignored):
> +  - spi-max-frequency - max frequency of spi bus
> +
> +
> +Example:
> +fmc: fmc at 1e620000 {
> +       compatible = "aspeed,ast2500-fmc";
> +       reg = < 0x1e620000 0x94
> +               0x20000000 0x02000000 >;
> +       #address-cells = <1>;
> +       #size-cells = <0>;
> +       interrupts = <19>;
> +       flash at 0 {
> +               reg = < 0 >;
> +               compatible = "jedec,spi-nor";
> +               /* spi-max-frequency = <>; */
> +               /* m25p,fast-read; */
> +               #address-cells = <1>;
> +               #size-cells = <1>;
> +       };
> +};
> --
> 2.7.4
>