Il 26/01/24 04:26, Chen-Yu Tsai ha scritto:
On Thu, Jan 25, 2024 at 7:39 PM AngeloGioacchino Del Regno
<angelogioacchino.delregno@xxxxxxxxxxxxx> wrote:
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@xxxxxxxxxxxx>
Signed-off-by: Chen-Yu Tsai <wenst@xxxxxxxxxxxx>
---
.../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#
(facepalm)
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? :-)
The function itself is fully probable and the implementation doesn't make
use of the WiFi's reset line, so I don't see any reason to describe it?
I don't actually know what the reset line does in the chip hardware.
This patch is just described what is already used.
+ 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@xxxxxxxxxxxx>
+
+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;
connected to?
Eh yes, sorry - I edited that statement multiple times and that "for" stuck
there for reasons :-)
on typical M.2 Key-E modules this is the W_DISABLE2# pin.
Otherwise this looks better. Thanks.
You're welcome!
Cheers!
ChenYu
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@xxxxxxxxxxxx>
L: linux-bluetooth@xxxxxxxxxxxxxxx
L: linux-mediatek@xxxxxxxxxxxxxxxxxxx (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
