qualcommbe: add Bluetooth support for Linksys LN6001

Enable the Bluetooth UART and pin configuration for Linksys Velop WRT
Pro 7 (LN6001/MBE70). Describe the ISP and reset outputs through the
existing named GPIO export mechanism, holding both high at boot.

Select the generic bluetooth-uart package in DEVICE_PACKAGES so images
include kmod-hci-uart and BlueZ btattach through its dependencies.
Initialize the LN6001 UCI defaults to attach /dev/ttyMSM1 using H4 at
115200 baud. Preserve already configured UARTs, including disabled ones.
The generic package remains disabled until a board or user configures it.

The combined series passed cold-start controller initialization, LE
discovery, connection and service discovery without a userspace reset
pulse. Keep Bluetooth support separate from Wi-Fi enablement.

Signed-off-by: Satoshi Ikeuchi <satosan.ikm@gmail.com>
Link: https://github.com/openwrt/openwrt/pull/25594
Signed-off-by: Robert Marko <robimarko@gmail.com>

target/linux/qualcommbe/dts/ipq9554-linksys-ln6001.dts

@@ -14,6 +14,7 @@
 
 	aliases {
 		serial0 = &blsp1_uart2;
+		serial1 = &blsp1_uart4;
 		led-boot = &led_blue;
 		led-failsafe = &led_red;
 		led-running = &led_blue;
@@ -24,6 +25,22 @@
 		stdout-path = "serial0:115200n8";
 	};
 
+	gpio-export {
+		compatible = "gpio-export";
+
+		bluetooth-isp {
+			gpio-export,name = "bluetooth-isp";
+			gpio-export,output = <1>;
+			gpios = <&tlmm 57 GPIO_ACTIVE_HIGH>;
+		};
+
+		bluetooth-reset {
+			gpio-export,name = "bluetooth-reset";
+			gpio-export,output = <1>;
+			gpios = <&tlmm 31 GPIO_ACTIVE_HIGH>;
+		};
+	};
+
 	keys {
 		compatible = "gpio-keys";
 		pinctrl-0 = <&keys_pins>;
@@ -81,6 +98,12 @@
 	status = "okay";
 };
 
+&blsp1_uart4 {
+	pinctrl-0 = <&uart4_pins>, <&bluetooth_pta_pins>;
+	pinctrl-names = "default";
+	status = "okay";
+};
+
 &mdio {
 	clock-frequency = <6250000>;
 	pinctrl-0 = <&mdio_pins>;
@@ -291,6 +314,13 @@
 };
 
 &tlmm {
+	bluetooth_pta_pins: bluetooth-pta-state {
+		pins = "gpio54", "gpio55", "gpio56";
+		function = "pta";
+		drive-strength = <8>;
+		bias-disable;
+	};
+
 	keys_pins: keys-state {
 		pins = "gpio37", "gpio40";
 		function = "gpio";
@@ -354,6 +384,13 @@
 			bias-pull-down;
 		};
 	};
+
+	uart4_pins: uart4-state {
+		pins = "gpio50", "gpio51", "gpio52", "gpio53";
+		function = "blsp4_uart";
+		drive-strength = <8>;
+		bias-disable;
+	};
 };
 
 /*

target/linux/qualcommbe/image/ipq95xx.mk

@@ -37,7 +37,7 @@ define Device/linksys_ln6001
 	DEVICE_MODEL := LN6001
 	DEVICE_DTS := ipq9554-linksys-ln6001
 	SOC := ipq9554
-	DEVICE_PACKAGES += kmod-leds-pwm kmod-fs-f2fs mkf2fs f2fsck
+	DEVICE_PACKAGES += bluetooth-uart kmod-leds-pwm kmod-fs-f2fs mkf2fs f2fsck
 	IMAGE/sysupgrade.bin/squashfs := append-rootfs | pad-to 64k | \
 		check-size 128m | sysupgrade-tar rootfs=$$$$@ | append-metadata
 endef

target/linux/qualcommbe/ipq95xx/base-files/etc/uci-defaults/03_bluetooth

@@ -0,0 +1,16 @@
+#!/bin/sh
+
+. /lib/functions.sh
+
+[ "$(board_name)" = "linksys,ln6001" ] || exit 0
+[ "$(uci -q get bluetooth-uart.main)" = "uart" ] || exit 0
+
+# Preserve an already configured UART, including a disabled one.
+[ -z "$(uci -q get bluetooth-uart.main.device)" ] || exit 0
+
+uci -q batch <<-EOF
+	set bluetooth-uart.main.device='/dev/ttyMSM1'
+	set bluetooth-uart.main.protocol='h4'
+	set bluetooth-uart.main.speed='115200'
+	set bluetooth-uart.main.enabled='1'
+EOF