MediaTek UART based Bluetooth Devices
==================================
This device is a serial attached device to UART device and thus it must be a
child node of the serial node with UART.
Please refer to the following documents for generic properties:
Documentation/devicetree/bindings/serial/serial.yaml
Required properties:
- compatible: Must be
"mediatek,mt7663u-bluetooth": for MT7663U device
"mediatek,mt7668u-bluetooth": for MT7668U device
- vcc-supply: Main voltage regulator
If the pin controller on the platform can support both pinmux and GPIO
control such as the most of MediaTek platform. Please use below properties.
- pinctrl-names: Should be "default", "runtime"
- pinctrl-0: Should contain UART RXD low when the device is powered up to
enter proper bootstrap mode.
- pinctrl-1: Should contain UART mode pin ctrl
Else, the pin controller on the platform only can support pinmux control and
the GPIO control still has to rely on the dedicated GPIO controller such as
a legacy MediaTek SoC, MT7621. Please use the below properties.
- boot-gpios: GPIO same to the pin as UART RXD and used to keep LOW when
the device is powered up to enter proper bootstrap mode when
- pinctrl-names: Should be "default"
- pinctrl-0: Should contain UART mode pin ctrl
Optional properties:
- reset-gpios: GPIO used to reset the device whose initial state keeps low,
if the GPIO is missing, then board-level design should be
guaranteed.
- clocks: Should be the clock specifiers corresponding to the entry in
clock-names property. If the clock is missing, then board-level
design should be guaranteed.
- clock-names: Should contain "osc" entry for the external oscillator.
- current-speed: Current baud rate of the device whose defaults to 921600
Example:
uart1_pins_boot: uart1-default {
pins-dat {
pinmux = <MT7623_PIN_81_URXD1_FUNC_GPIO81>;
output-low;
};
};
uart1_pins_runtime: uart1-runtime {
pins-dat {
pinmux = <MT7623_PIN_81_URXD1_FUNC_URXD1>,
<MT7623_PIN_82_UTXD1_FUNC_UTXD1>;
};
};
uart1: serial@11003000 {
compatible = "mediatek,mt7623-uart",
"mediatek,mt6577-uart";
reg = <0 0x11003000 0 0x400>;
interrupts = <GIC_SPI 52 IRQ_TYPE_LEVEL_LOW>;
clocks = <&pericfg CLK_PERI_UART1_SEL>,
<&pericfg CLK_PERI_UART1>;
clock-names = "baud", "bus";
bluetooth {
compatible = "mediatek,mt7663u-bluetooth";
vcc-supply = <®_5v>;
reset-gpios = <&pio 24 GPIO_ACTIVE_LOW>;
pinctrl-names = "default", "runtime";
pinctrl-0 = <&uart1_pins_boot>;
pinctrl-1 = <&uart1_pins_runtime>;
current-speed = <921600>;
};
};