mcu-firmware: include host support for 'hci_uart' firmware

This includes shell script for host side support of the 'hci_uart' MCU
firmware type. The script calls 'btattach' with matching tty interface
and baud rate as arguments, resulting in new Bluetooth HCI controller
registration in the system. Both UART and USB interfaces are supported.

Signed-off-by: Piotr Dymacz <pepe2k@gmail.com>

feeds/mcu/mcu-firmware/Makefile

@@ -8,7 +8,7 @@
 include $(TOPDIR)/rules.mk
 
 PKG_NAME:=mcu-firmware
-PKG_VERSION:=2023-03-10
+PKG_VERSION:=2023-03-12
 PKG_RELEASE:=1
 
 PKG_MAINTAINER:=Piotr Dymacz <pepe2k@gmail.com>

feeds/mcu/mcu-firmware/files/hci_uart/etc/mcu.d/hci_uart.sh

@@ -0,0 +1,79 @@
+#!/bin/sh
+
+. /lib/functions.sh
+. /lib/functions/mcu.sh
+
+attach_hci_controller() {
+	local section="$1"
+
+	local sn
+	local pid
+	local interface
+	local uart_path
+	local uart_baud
+	local uart_flow
+
+	[ -n "$section" ] || return 1
+	command -v btattach > /dev/null 2>&1 || return 1
+
+	config_load mcu
+	config_get sn "$section" sn
+	config_get interface "$section" interface
+	config_get uart_path "$section" uart_path
+	config_get uart_baud "$section" uart_baud "115200"
+	config_get uart_flow "$section" uart_flow "0"
+
+	[ -n "$sn" ] || return 1
+
+	if [ "$interface" = "usb" ]; then
+		uart_baud="1000000"
+		uart_flow="1"
+
+		dev_found=""
+		usb_path="/sys/bus/usb/devices/*"
+		for dev_path in $usb_path; do
+			dev="$(basename "$dev_path")"
+			[[ $dev == *":"* ]] && continue
+
+			[ "$sn" = "$(cat "${dev_path}/serial" 2>/dev/null)" ] && {
+				dev_found="$dev"
+				break
+			}
+		done
+
+		[ -n "$dev_found" ] || return 1
+
+		usb_path="/sys/bus/usb/devices/${dev_found}*/tty/*"
+		for tty_path in $usb_path; do
+			tty="$(basename "$tty_path")"
+			[ -c "/dev/${tty}" ] && {
+				uart_path="/dev/${tty}"
+				break
+			}
+		done
+	fi
+
+	[ -c "$uart_path" ] || return 1
+
+	# Give MCU some time for BLE controller setup
+	sleep 1
+
+	if [ "$uart_flow" = "1" ]; then
+		btattach -B "$uart_path" -S "$uart_baud" > /dev/null 2>&1 &
+	else
+		btattach -B "$uart_path" -S "$uart_baud" -N > /dev/null 2>&1 &
+	fi
+
+	pid="$!"
+
+	kill -0 "$pid" > /dev/null 2>&1 && {
+		echo "$pid" > "/var/run/mcu.${sn}.pid"
+		return 0
+	}
+
+	return 1
+}
+
+attach_hci_controller "$1" || exit 1
+
+exit 0