Re: [PATCH v2 02/24] dt-bindings: introduce silabs,wfx.yaml

[Rob Herring <robh@kernel.org>]

On Tue, Oct 20, 2020 at 02:57:55PM +0200, Jerome Pouiller wrote:
> From: Jérôme Pouiller <jerome.pouiller@silabs.com>
> 
> Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
> ---
>  .../bindings/net/wireless/silabs,wfx.yaml     | 133 ++++++++++++++++++
>  1 file changed, 133 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/net/wireless/silabs,wfx.yaml
> 
> diff --git a/Documentation/devicetree/bindings/net/wireless/silabs,wfx.yaml b/Documentation/devicetree/bindings/net/wireless/silabs,wfx.yaml
> new file mode 100644
> index 000000000000..2605e9fed185
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/net/wireless/silabs,wfx.yaml
> @@ -0,0 +1,133 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +# Copyright (c) 2020, Silicon Laboratories, Inc.
> +%YAML 1.2
> +---
> +
> +$id: http://devicetree.org/schemas/net/wireless/silabs,wfx.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Silicon Labs WFxxx devicetree bindings
> +
> +maintainers:
> +  - Jérôme Pouiller <jerome.pouiller@silabs.com>
> +
> +description: >
> +  Support for the Wifi chip WFxxx from Silicon Labs. Currently, the only device
> +  from the WFxxx series is the WF200 described here:
> +     https://www.silabs.com/documents/public/data-sheets/wf200-datasheet.pdf
> +  
> +  The WF200 can be connected via SPI or via SDIO.
> +  
> +  For SDIO:
> +  
> +    Declaring the WFxxx chip in device tree is mandatory (usually, the VID/PID is
> +    sufficient for the SDIO devices).
> +  
> +    It is recommended to declare a mmc-pwrseq on SDIO host above WFx. Without
> +    it, you may encounter issues during reboot. The mmc-pwrseq should be
> +    compatible with mmc-pwrseq-simple. Please consult
> +    Documentation/devicetree/bindings/mmc/mmc-pwrseq-simple.txt for more
> +    information.
> +  
> +  For SPI:
> +  
> +    In add of the properties below, please consult
> +    Documentation/devicetree/bindings/spi/spi-controller.yaml for optional SPI
> +    related properties.
> +
> +properties:
> +  compatible:
> +    const: silabs,wf200
> +
> +  reg:
> +    description:
> +      When used on SDIO bus, <reg> must be set to 1. When used on SPI bus, it is
> +      the chip select address of the device as defined in the SPI devices
> +      bindings.
> +    maxItems: 1
> +
> +  spi-max-frequency: true
> +
> +  interrupts:
> +    description: The interrupt line. Triggers IRQ_TYPE_LEVEL_HIGH and
> +      IRQ_TYPE_EDGE_RISING are both supported by the chip and the driver. When
> +      SPI is used, this property is required. When SDIO is used, the "in-band"
> +      interrupt provided by the SDIO bus is used unless an interrupt is defined
> +      in the Device Tree.
> +    maxItems: 1
> +
> +  reset-gpios:
> +    description: (SPI only) Phandle of gpio that will be used to reset chip
> +      during probe. Without this property, you may encounter issues with warm
> +      boot. (For legacy purpose, the gpio in inverted when compatible ==
> +      "silabs,wfx-spi")
> +
> +      For SDIO, the reset gpio should declared using a mmc-pwrseq.
> +    maxItems: 1
> +
> +  wakeup-gpios:
> +    description: Phandle of gpio that will be used to wake-up chip. Without this
> +      property, driver will disable most of power saving features.
> +    maxItems: 1
> +
> +  config-file:

If this is antenna data/config, then make the property name more 
specific. And it needs a vendor prefix as it is vendor specific.

> +    description: Use an alternative file as PDS. Default is `wf200.pds`.
> +
> +  local-mac-address:
> +    $ref: /net/ethernet-controller.yaml#/properties/local-mac-address
> +
> +  mac-address:
> +    $ref: /net/ethernet-controller.yaml#/properties/mac-address

I'd rather see these properties refactored out to their own file. We 
should probably have a wifi-controller.yaml that has these as well as 
enforcing the node name 'wifi'.

> +
> +additionalProperties: true

What properties? This shouldn't be true. If you need spi-cpol or 
spi-cpha, then you should list those. Really, if the SPI mode of the 
device is fixed, then you should never use those. 

> +
> +required:
> +  - compatible
> +  - reg
> +
> +examples:
> +  - |
> +    #include <dt-bindings/gpio/gpio.h>
> +    #include <dt-bindings/interrupt-controller/irq.h>
> +
> +    spi0 {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        wfx@0 {
> +            compatible = "silabs,wf200";
> +            pinctrl-names = "default";
> +            pinctrl-0 = <&wfx_irq &wfx_gpios>;
> +            reg = <0>;
> +            interrupts-extended = <&gpio 16 IRQ_TYPE_EDGE_RISING>;
> +            wakeup-gpios = <&gpio 12 GPIO_ACTIVE_HIGH>;
> +            reset-gpios = <&gpio 13 GPIO_ACTIVE_LOW>;
> +            spi-max-frequency = <42000000>;
> +        };
> +    };
> +
> +  - |
> +    #include <dt-bindings/gpio/gpio.h>
> +    #include <dt-bindings/interrupt-controller/irq.h>
> +
> +    wfx_pwrseq: wfx_pwrseq {
> +        compatible = "mmc-pwrseq-simple";
> +        pinctrl-names = "default";
> +        pinctrl-0 = <&wfx_reset>;
> +        reset-gpios = <&gpio 13 GPIO_ACTIVE_LOW>;
> +    };
> +
> +    mmc0 {
> +        mmc-pwrseq = <&wfx_pwrseq>;
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        mmc@1 {

wifi@1

> +            compatible = "silabs,wf200";
> +            pinctrl-names = "default";
> +            pinctrl-0 = <&wfx_wakeup>;
> +            reg = <1>;
> +            wakeup-gpios = <&gpio 12 GPIO_ACTIVE_HIGH>;
> +        };
> +    };
> +...
> -- 
> 2.28.0
>