如题，软链接也做了。但一直如下图所示。
zqh@zqh-PC:~$ sudo lsusb -s 1:8
Bus 001 Device 008: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port
zqh@zqh-PC:~$ lsusb
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 004: ID 04f2:b48c Chicony Electronics Co., Ltd
Bus 001 Device 003: ID 046d:c53f Logitech, Inc.
Bus 001 Device 008: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
zqh@zqh-PC:~$ dmesg | grep tty
[    0.000000] console [tty0] enabled
[    6.020554] usb 1-1: pl2303 converter now attached to ttyUSB0
[ 1888.853468] pl2303 ttyUSB0: pl2303 converter now disconnected from ttyUSB0
[ 4811.480406] usb 1-1: pl2303 converter now attached to ttyUSB0
[ 4839.283591] pl2303 ttyUSB0: pl2303 converter now disconnected from ttyUSB0
[ 4846.367232] usb 1-1: pl2303 converter now attached to ttyUSB0
[ 4860.393749] pl2303 ttyUSB0: pl2303 converter now disconnected from ttyUSB0
[ 4864.259074] usb 1-2: pl2303 converter now attached to ttyUSB0
[ 4870.343466] pl2303 ttyUSB0: pl2303 converter now disconnected from ttyUSB0
[ 4872.534847] usb 1-1: pl2303 converter now attached to ttyUSB0
zqh@zqh-PC:~$

一直提示disconnected。不知要怎么办。