fully supported by: http::/busmatic.de/

*** RaspberryMatic/piVCCU compatibility mode ***

create a udev-rule as:

root@homematic-raspi:~# cat /lib/udev/rules.d/99-ftdi-rfusb.rules
ACTION=="add", ATTR{product}=="HmUL*", ATTRS{idVendor}=="0403", ATTRS{manufacturer}=="busware*", RUN+="/sbin/modprobe hb_rf_usb" RUN+="/bin/sh -c 'echo 0403 $attr{idProduct} > /sys/bus/usb/drivers/hb_rf_usb/new_id'"

root@homematic-raspi:~# udevadm control --reload

or reboot

if you don't have shell access, you may re-set the PID of the used standard FTDI USB chip by: 
./ft232r_prog --dump --new-pid 0x6f70 --old-pid 0x6bf0 --manufacturer "Alexander Reinert" --product "HB-RF-USB" 

*** Driver LED pinning ***

https://github.com/alexreinert/piVCCU/blob/master/kernel/generic_raw_uart.h

enum generic_raw_uart_pin
{
  GENERIC_RAW_UART_PIN_BLUE = 0,
  GENERIC_RAW_UART_PIN_GREEN = 1,
  GENERIC_RAW_UART_PIN_RED = 2,
  GENERIC_RAW_UART_PIN_RESET = 3,
  GENERIC_RAW_UART_PIN_ALT_RESET = 4,
};

*** use of native FTDI_SIO kernel module (without udev rule) ***

to lower USB latency:
echo 1 > /sys/bus/usb-serial/devices/ttyUSB0/latency_timer

add to udev rules:
ACTION=="add", SUBSYSTEM=="usb-serial", DRIVER=="ftdi_sio", ATTR{latency_timer}="1"