Plug the USB-serial adapter into Intel Edison USB OTG host port. Check if new device is seen, from Edison terminal:

dmesg

If there isn’t a new assignment to /dev/ttyUSB*, the FTDI kernel module may be needed.

opkg install kernel-module-ftdi-sio

This assumes you have already setup the Intel Edison opkg repository.

Verify USB-serial adapter in Edison terminal

dmesg

The reply should include

usb: FTDI USB Serial Device converter now attached to ttyUSB0

You may have to update kernel if this doesn’t work.

Which Intel Edison Yocto version is installed?

configure_edison --version