Download driver you need and copy to your
NAS.
Place the drivers in /lib/modules folder.
Then run:
sudo insmod /lib/modules/usbserial.ko
sudo insmod /lib/modules/cp210x.ko
If your driver is cp210x.ko.
You can also download the start-usb-drivers.sh script and copy to folder: /usr/local/etc/rc.d/start-usb-drivers.sh
Then: chmod +x /usr/local/etc/rc.d/start-usb-drivers.sh
The the drivers will be loaded when you reboot your
NAS.
You must edit the start-usb-drivers.sh script if you want to load another driver.