RE: [v3 1/4] dt-bindings: spi: Add binding file for ASPEED FMC/SPI memory controller

Chin-Ting Kuo
2020-11-06T09:11:18Z

Hi Rob,

> -----Original Message-----
> From: Rob Herring <robh@kernel.org>
> Sent: Friday, November 6, 2020 6:40 AM
> To: Chin-Ting Kuo <chin-ting_kuo@aspeedtech.com>
> Cc: broonie@kernel.org; joel@jms.id.au; andrew@aj.id.au; clg@kaod.org;
> bbrezillon@kernel.org; devicetree@vger.kernel.org;
> linux-kernel@vger.kernel.org; linux-aspeed@lists.ozlabs.org;
> linux-spi@vger.kernel.org; BMC-SW <BMC-SW@aspeedtech.com>
> Subject: Re: [v3 1/4] dt-bindings: spi: Add binding file for ASPEED FMC/SPI
> memory controller
>
> On Thu, Nov 05, 2020 at 08:03:28PM +0800, Chin-Ting Kuo wrote:
> > Create binding file with YAML syntax for ASPEED FMC/SPI memory
> controller.
> >
> > Signed-off-by: Chin-Ting Kuo <chin-ting_kuo@aspeedtech.com>
> > ---
> > .../bindings/spi/aspeed,spi-aspeed.yaml | 66
> +++++++++++++++++++
> > 1 file changed, 66 insertions(+)
> > create mode 100644
> > Documentation/devicetree/bindings/spi/aspeed,spi-aspeed.yaml
> >
> > diff --git
> > a/Documentation/devicetree/bindings/spi/aspeed,spi-aspeed.yaml
> > b/Documentation/devicetree/bindings/spi/aspeed,spi-aspeed.yaml
> > new file mode 100644
> > index 000000000000..41b9692c7226
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/spi/aspeed,spi-aspeed.yaml
> > @@ -0,0 +1,66 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) %YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/spi/aspeed,spi-aspeed.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: SPI memory controller for ASPEED SoCs
> > +
> > +maintainers:
> > + - Chin-Ting Kuo <chin-ting_kuo@aspeedtech.com>
> > +
> > +description: |
> > + There are three SPI memory controllers embedded in a ASPEED SoC.
> > + They are usually connected to SPI NOR flashes. Each of them has
> > + more than a chip select. They also support SPI single, dual and
> > + quad IO modes for SPI NOR flash.
> > +
> > +allOf:
> > + - $ref: /spi/spi-controller.yaml#
> > +
> > +properties:
> > + compatible:
> > + oneOf:
> > + - items:
>
> You can drop oneOf (there's only 1) and items.

Okay, it will be removed on the next patch version.

> > + - enum:
> > + - aspeed,ast2600-fmc
> > + - aspeed,ast2600-spi
> > +
> > + reg:
> > + items:
> > + - description: the control register location and length
> > + - description: the flash memory mapping address and length
> > +
> > + clocks:
> > + description: AHB bus clock which will be converted to SPI bus
> > + clock
>
> maxItems: 1

it will be added on the next patch version.

>
> Constraints on num-cs values? Or up to 2^32 is good?
>

The maximum is 3.
The "maximum" item will be added on the next patch version

> > +
> > +required:
> > + - compatible
> > + - reg
> > + - clocks
> > + - num-cs
> > +
> > +unevaluatedProperties: false
> > +
> > +examples:
> > + - |
> > + #include <dt-bindings/clock/ast2600-clock.h>
> > + spi1: spi@1e630000 {
> > + compatible = "aspeed,ast2600-spi";
> > + reg = <0x1e630000 0xc4>, <0x30000000 0x10000000>;
> > + reg-names = "spi_ctrl_reg", "spi_mmap";
> > + clocks = <&syscon ASPEED_CLK_AHB>;
> > + num-cs = <2>;
> > + #address-cells = <1>;
> > + #size-cells = <0>;
> > + flash@0 {
> > + compatible = "jedec,spi-nor";
> > + reg = <0>;
> > + spi-max-frequency = <50000000>;
> > + };
> > + flash@1 {
> > + compatible = "jedec,spi-nor";
> > + reg = <1>;
> > + spi-max-frequency = <50000000>;
> > + };
> > + };
> > --
> > 2.17.1
> >

Best Wishes,
Chin-Ting