[PATCH 2/2] dt: bindings: Add binding for ESP8089 wifi chips

[Icenowy Zheng]

08.08.2016, 02:58, "Hans de Goede" <hdegoede at redhat.com>:
> The ESP8089 chips can mostly be enumerated via their sdio interface,
> but they are clocked by an external crystal which may differ from one
> board to the other.
>
> This commit adds a binding for the sdio child node for these chips,
> allowing to specify the external crystal type (for now, this binding
> could be be extended with e.g. OOB irq support later).
>
> The Android driver for this chip uses a text file with key,value pairs
> which gets loaded as firmware to pass this info to the firmware.
> The "esp,crystal_26M_en" name is chosen to match the crystal_26M_en
> key-name in that text file.
>
> Note that at this point there only is an out of tree driver for this
> hardware, there is no clear timeline / path for merging this. Still
> I believe it would be good to specify the binding for this in tree
> now, so that any future migration to an in tree driver will not cause
> compatiblity issues.
>
> Cc: Icenowy Zheng <icenowy at aosc.xyz>
> Signed-off-by: Hans de Goede <hdegoede at redhat.com>
> ---
>  .../bindings/net/wireless/esp,esp8089.txt | 31 ++++++++++++++++++++++
>  1 file changed, 31 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/net/wireless/esp,esp8089.txt
>
> diff --git a/Documentation/devicetree/bindings/net/wireless/esp,esp8089.txt b/Documentation/devicetree/bindings/net/wireless/esp,esp8089.txt
> new file mode 100644
> index 0000000..898a149
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/net/wireless/esp,esp8089.txt
> @@ -0,0 +1,31 @@
> +Espressif ESP8089 wireless SDIO devices
> +
> +This node provides properties for controlling the ESP8089 wireless device.
> +The node is expected to be specified as a child node to the SDIO controller
> +that connects the device to the system.
> +
> +Required properties:
> +
> + - compatible : Should be "esp,esp8089".
There's also esp8266. (And the difference of 8089 and 8266 is mainly the difference of crystal frequency... 26MHz for 8266, 40MHz for 8089)
So maybe it should be the difference of dt compatible?
> +
> +Optional properties:
> + - esp,crystal_26M_en: Integer value for the crystal_26M_en firmware parameter
> +
> +Example:
> +
> +&mmc1 {
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + vmmc-supply = <&reg_dldo1>;
> + mmc-pwrseq = <&wifi_pwrseq>;
> + bus-width = <4>;
> + non-removable;
> + status = "okay";
> +
> + esp8089: sdio_wifi at 1 {
> + compatible = "esp,esp8089";
> + reg = <1>;
> + esp,crystal_26M_en = <2>;
> + };
> +};
> --
> 2.7.4