Comment 5 for bug 291385

I think so, but looking at dmesg I noticed that when I connect the device I get two USB serial devices (ttyUSB0 and ttyUSB1) as can be seen below.

I have connected to both via minicom and they both respond to "AT" with "OK".

Using ttyUSB0 I did the following:
input: AT+CPIN?
response: +CPIN: SIM PIN
response:
response: OK
input: AT+CPIN=9999
response: OK
input: AT&F
response: +ZDONR: "Not Found"
response:
response: +ZPASR: "No Service"
response:
response: +ZDONR: "Telstra",505,1,"CS_ONLY","ROAM_OFF"
response:
response: +ZPASR: "UMTS"
response:
response: +ZDONR: "Telstra",505,1,"CS_ONLY","ROAM_OFF"
response:
response: +ZPASR: "UMTS"
response:
response: +ZDONR: "Telstra",505,1,"CS_PS","ROAM_OFF"
response:
response: +ZPASR: "UMTS"
response:
response: +ZUSIMR:2
.. the above response is repeated every second
input: ATD*99#
response: CONNECT

After the CONNECT I no longer get any response from minicom key inputs. So I fired up another instance of minicom connected to ttyUSB1 and I was able to enter commands all the while getting "+ZUSIMR:2" echoed to the screen. So I issued an ath on ttyUSB1 and ttyUSB0 start responding again (and outputting "+ZUSIMR:2").

I also tried the same thing swapping ttyUSB0 and ttyUSB1, it didn't make any difference.

So hopefully to answer your questions, I believe ttyUSB0 would be valid.

dmeg output:
Nov 3 11:38:21 itxtgmarkc kernel: [ 7863.256112] pccard: CardBus card inserted into slot 0
Nov 3 11:38:21 itxtgmarkc kernel: [ 7863.256291] pci 0000:04:00.0: PME# supported from D0 D1 D2 D3hot
Nov 3 11:38:21 itxtgmarkc kernel: [ 7863.256301] pci 0000:04:00.0: PME# disabled
Nov 3 11:38:21 itxtgmarkc kernel: [ 7863.258305] ohci_hcd 0000:04:00.0: enabling device (0000 -> 0002)
Nov 3 11:38:21 itxtgmarkc kernel: [ 7863.258419] ohci_hcd 0000:04:00.0: PCI INT A -> GSI 21 (level, low) -> IRQ 21
Nov 3 11:38:21 itxtgmarkc kernel: [ 7863.258463] ohci_hcd 0000:04:00.0: OHCI Host Controller
Nov 3 11:38:21 itxtgmarkc kernel: [ 7863.262576] ohci_hcd 0000:04:00.0: new USB bus registered, assigned bus number 6
Nov 3 11:38:21 itxtgmarkc kernel: [ 7863.264515] ohci_hcd 0000:04:00.0: irq 21, io mem 0xc8000000
Nov 3 11:38:21 itxtgmarkc kernel: [ 7863.322295] usb usb6: configuration #1 chosen from 1 choice
Nov 3 11:38:21 itxtgmarkc kernel: [ 7863.323061] hub 6-0:1.0: USB hub found
Nov 3 11:38:21 itxtgmarkc kernel: [ 7863.323361] hub 6-0:1.0: 3 ports detected
Nov 3 11:38:26 itxtgmarkc kernel: [ 7867.745901] usb 6-1: new full speed USB device using ohci_hcd and address 2
Nov 3 11:38:26 itxtgmarkc kernel: [ 7867.974917] usb 6-1: configuration #1 chosen from 1 choice
Nov 3 11:38:26 itxtgmarkc kernel: [ 7867.978521] option 6-1:1.0: GSM modem (1-port) converter detected
Nov 3 11:38:26 itxtgmarkc kernel: [ 7867.980485] usb 6-1: GSM modem (1-port) converter now attached to ttyUSB0
Nov 3 11:38:26 itxtgmarkc kernel: [ 7867.993464] option 6-1:1.1: GSM modem (1-port) converter detected
Nov 3 11:38:26 itxtgmarkc kernel: [ 7867.994069] usb 6-1: GSM modem (1-port) converter now attached to ttyUSB1