WhyCan Forum(哇酷开发者社区)

root@ubuntu:/sys/kernel/config/usb_gadget/g1# ls /sys/class/udc/
3550000.xudc
root@ubuntu:/sys/kernel/config/usb_gadget/g1# echo 3550000.xudc > UDC
[ 1032.949902] udc-core: couldn't find an available UDC or it's busy
bash: echo: write error: Device or resource busy
root@ubuntu:/sys/kernel/config/usb_gadget/g1# lsusb
Bus 002 Device 002: ID 0bda:0489 Realtek Semiconductor Corp. 4-Port USB 3.0 Hub
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 002: ID 0bda:5489 Realtek Semiconductor Corp. 4-Port USB 2.0 Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

我把所有的usb设备都拔掉了，使用串口，一直报设备 busy 的错误，有大佬遇过这个问题吗