How can I know what device nodes exist for a USB device?

Question

I attached GSM Modem on Kubuntu Linux via USB. How will I know the exact path to the device ? It gets detected by the system and when I run lsusb I see the following:

rvb@rvb:/dev$ lsusb
Bus 008 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 007 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 006 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 002 Device 007: ID 12d1:1446 Huawei Technologies Co., Ltd. 
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 002: ID 04f2:b070 Chicony Electronics Co., Ltd 
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

The device I plugged in is listed as Huawei Technologies Co., Ltd. Will I know if my device is on /dev/ just by looking at the output above?

Answer 1

Try running lshw, and see if you see anything about a modem or a serial device. Try running dmesg a couple times directly after connecting the device. If the USB devices is recognized you may see notices about it setting up something under /dev/ttyS*

Answer 2

For a usb stick you can do ls -l /sys/dev/block which will give you a list of all block devices that the kernel and udev recognize even before the device is mounted. The output will include something like ../../devices/pci0000:00/0000:00:1d.7/usb1......./block/sda/sda1 So the new device is /dev/sda1

Your usb modem is probably a character device so try ls -l /sys/dev/char and look for a new entry after it is turned on. For a usb printer I get ../../devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/usb/lp0 so the new device is /dev/lp0 and is a character device.