DCcduino Mega 2560

USB2.0-Serial:
 Vendor ID:   0x1a86
 Product ID:   0x7523
 Version:    2.54
 Speed:   Up to 12 Mb/sec
 Location ID:   0xfd130000 / 5
 Current Available (mA):   500
 Current Required (mA):   Unknown (Device has not been configured)

USB serial adapters

kmod-usb-serial-ch341
 
1a86  QinHeng Electronics
    5523  CH341 in serial mode, usb to serial port converter
    7523  HL-340 USB-Serial adapter
    7584  CH340S
opkg update
opkg install kmod-usb-serial kmod-usb-serial-ch341