# Udev rule to auto-start dcc-usb-connector.service when USB device is connected
#
# This rule detects when a CH340 USB-to-serial adapter (ID 1a86:7523)
# is connected and assigned to /dev/ttyUSB0, then automatically starts
# the dcc-usb-connector.service (user systemd service).
#
# Installation:
#   sudo cp 99-dcc-usb-connector.rules /etc/udev/rules.d/
#   sudo udevadm control --reload-rules
#   sudo udevadm trigger --subsystem-match=tty
#
# Testing:
#   udevadm test /sys/class/tty/ttyUSB0
#   udevadm monitor --property --subsystem-match=tty
#
# The service will be started/stopped automatically when the device
# is plugged in/unplugged.

# Match USB device 1a86:7523 on ttyUSB0 and trigger user systemd service
SUBSYSTEM=="tty", ATTRS{idVendor}=="1a86", ATTRS{idProduct}=="7523", KERNEL=="ttyUSB0", TAG+="systemd", ENV{SYSTEMD_USER_WANTS}="dcc-usb-connector.service"