TS-7970 USB Device
From embeddedTS Manuals
This SBC includes support to act as a USB peripheral to another system. Remove the "CON EN" jumper to disable the on-board USB serial debug port and connect the USB device port (connector) to the CPU's OTG port. The CPU port is strapped to only act as a USB device. Several devices are compiled into the default kernel. Other devices can be compiled into the kernel by following the compile the kernel section.
USB Serial
modprobe g_serial use_acm=1
This will create the device "/dev/ttyGS0". See the kernel documentation for more information:
USB Ethernet
modprobe g_ether
This provides a "usb0" network interface. This driver simulates an Ethernet network connection between the host PC and the i.MX6.