Re: [PATCH 1/2] dt-bindings: net: bluetooth: Add MediaTek MT7921S SDIO Bluetooth

[AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>]

Il 25/01/24 10:52, Chen-Yu Tsai ha scritto:
> The MediaTek MT7921S is a WiFi/Bluetooth combo chip that works over
> SDIO. While the Bluetooth function is fully discoverable, the chip
> has a pin that can reset just the Bluetooth side, as opposed to the
> full chip. This needs to be described in the device tree.
> 
> Add a device tree binding for MT7921S Bluetooth over SDIO specifically
> ot document the reset line.
> 
> Cc: Sean Wang <sean.wang@mediatek.com>
> Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
> ---
>   .../bluetooth/mediatek,mt7921s-bluetooth.yaml | 49 +++++++++++++++++++
>   MAINTAINERS                                   |  1 +
>   2 files changed, 50 insertions(+)
>   create mode 100644 Documentation/devicetree/bindings/net/bluetooth/mediatek,mt7921s-bluetooth.yaml
> 
> diff --git a/Documentation/devicetree/bindings/net/bluetooth/mediatek,mt7921s-bluetooth.yaml b/Documentation/devicetree/bindings/net/bluetooth/mediatek,mt7921s-bluetooth.yaml
> new file mode 100644
> index 000000000000..bbe240e7cc40
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/net/bluetooth/mediatek,mt7921s-bluetooth.yaml
> @@ -0,0 +1,49 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/net/bluetooth/mediatek,mt7921s-bluetooth.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: MediaTek MT7921S Bluetooth
> +

title:

maintainers:

description:

... and then, you missed

allOf:
   - $ref: bluetooth-controller.yaml#

Everything else looks good.

Cheers,
Angelo

> +description:

MT7921S is a (dual?) SDIO-attached dual-radio WiFi+Bluetooth combo chip;
this chip has two dedicated reset lines, one of which is used to reset
the Bluetooth core.
The WiFi part of this chip is described in ....where? :-)

> +  This binding describes the Bluetooth side of the SDIO-attached MT7921S
> +  WiFi+Bluetooth combo chips. These chips are dual-radio chips supporting
> +  WiFi and Bluetooth. Bluetooth works over SDIO just like WiFi. Bluetooth
> +  has its own reset line, separate from WiFi, which can be used to reset
> +  the Bluetooth core.
> +
> +maintainers:
> +  - Sean Wang <sean.wang@mediatek.com>
> +
> +properties:
> +  compatible:
> +    enum:
> +      - mediatek,mt7921s-bluetooth
> +  reg:
> +    const: 2
> +
> +  reset-gpios:
> +    maxItems: 1
> +    description: A GPIO line connected to the Bluetooth subsystem reset line.
> +      Typically the W_DISABLE2# pin on M.2 E-key modules. If present this
> +      shall be flagged as active low.

description:
   An active-low reset line connected for the Bluetooth core;
   on typical M.2 Key-E modules this is the W_DISABLE2# pin.

Cheers,
Angelo

> +
> +required:
> +  - compatible
> +  - reg
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    mmc {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        bluetooth@2 {
> +            compatible = "mediatek,mt7921s-bluetooth";
> +            reg = <2>;
> +            reset-gpios = <&pio 8 GPIO_ACTIVE_LOW>;
> +        };
> +    };
> diff --git a/MAINTAINERS b/MAINTAINERS
> index b64a64ca7916..662957146852 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -13657,6 +13657,7 @@ M:	Sean Wang <sean.wang@mediatek.com>
>   L:	linux-bluetooth@vger.kernel.org
>   L:	linux-mediatek@lists.infradead.org (moderated for non-subscribers)
>   S:	Maintained
> +F:	Documentation/devicetree/bindings/net/bluetooth/mediatek,mt7921s-bluetooth.yaml
>   F:	Documentation/devicetree/bindings/net/mediatek-bluetooth.txt
>   F:	drivers/bluetooth/btmtkuart.c
>