one GSM/GPRS/3G usb stick modem creates 3 usb serial devices
Hello,
I'm running a Slackware 13 box, and after a bit of struggle I managed to make my mobile internet usb stick to work with linux. After enabling a few kernel modules (symbols: USB_SERIAL, USB_SERIAL_GENERIC and USB_SERIAL_OPTION) and made a small udev rule which literally ejects the stick which gets firstly detected and mounted by hal as a scsi cdrom, three usb serial devices are created: /dev/ttyUSB{0,1,2}. By trial and error I managed to successfully use /dev/ttyUSB2 to dial in and connect.
What puzzles me is why the 3 devices created? Are there 3 physical devices contended within the stick which get detected and may serve other purposes, from which only one is the plain modem or is it a driver issue/redundancy?
I can provide syslog messages and udev information (events, environment, etc) if needed.
Any thoughts are greatly appreciated.
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