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slash_blog

Member

Registered: 2010-07-29

Posts: 15

USB Modem not working

Hi,

I am trying to use a USB modem. On one system it is working fine, and I can connect to internet using wvdial.

However on the other system, udev (I suppose) keeps on creating and deleting the modem device (/dev/ttyACM0).

The corresponding dmesg output is as follows:

[  321.393330] usb 3-2: new full speed USB device number 19 using ohci_hcd
[  321.598214] scsi16 : usb-storage 3-2:1.0
[  326.706714] usb 3-2: USB disconnect, device number 19
[  327.463332] usb 3-2: new full speed USB device number 20 using ohci_hcd
[  331.178187] usb 3-2: USB disconnect, device number 20
[  333.329998] usb 3-2: new full speed USB device number 21 using ohci_hcd
[  333.534895] scsi17 : usb-storage 3-2:1.0
[  338.627479] usb 3-2: USB disconnect, device number 21
[  339.356673] usb 3-2: new full speed USB device number 22 using ohci_hcd
[  343.071880] usb 3-2: USB disconnect, device number 22
[  345.223328] usb 3-2: new full speed USB device number 23 using ohci_hcd
[  345.428238] scsi18 : usb-storage 3-2:1.0
[  350.521072] usb 3-2: USB disconnect, device number 23
[  351.250003] usb 3-2: new full speed USB device number 24 using ohci_hcd
[  354.965200] usb 3-2: USB disconnect, device number 24
[  357.116665] usb 3-2: new full speed USB device number 25 using ohci_hcd
[  357.325564] scsi19 : usb-storage 3-2:1.0
[  362.414036] usb 3-2: USB disconnect, device number 25
[  363.146664] usb 3-2: new full speed USB device number 26 using ohci_hcd
[  366.861528] usb 3-2: USB disconnect, device number 26
[  369.016686] usb 3-2: new full speed USB device number 27 using ohci_hcd
[  369.222243] scsi20 : usb-storage 3-2:1.0
[  374.312014] usb 3-2: USB disconnect, device number 27
[  375.040015] usb 3-2: new full speed USB device number 28 using ohci_hcd
[  378.755186] usb 3-2: USB disconnect, device number 28
[  380.906655] usb 3-2: new full speed USB device number 29 using ohci_hcd
[  381.111564] scsi21 : usb-storage 3-2:1.0
[  386.202021] usb 3-2: USB disconnect, device number 29
[  386.929992] usb 3-2: new full speed USB device number 30 using ohci_hcd
[  390.645540] usb 3-2: USB disconnect, device number 30
[  392.796662] usb 3-2: new full speed USB device number 31 using ohci_hcd
[  393.001571] scsi22 : usb-storage 3-2:1.0
[  398.094272] usb 3-2: USB disconnect, device number 31
[  398.823324] usb 3-2: new full speed USB device number 32 using ohci_hcd

As one can see, the device keeps connecting and disconnecting.
Both the boxes are using 3.0-ARCH kernel.

Also, lsusb command output for the device is as follows:

Bus 002 Device 017: ID 15eb:1231

Can somebody please help in fixing this issue?

TIA.

njoerd

Member

Registered: 2011-09-18

Posts: 6

Re: USB Modem not working

You are trying to access the net using a storage device.
Try something like "modeswitch" to use it as a modem.

hth

slash_blog

Member

Registered: 2010-07-29

Posts: 15

Re: USB Modem not working

Thanks for your reply njoerd. I did try a few things during the past couple of days (including modeswitch: usb_modeswitch -v 15eb -p 1231).

The only change that it brought is the following:

[357545.352940] generic ttyUSB0: generic converter now disconnected from ttyUSB0
[357545.352979] usbserial_generic 3-2:1.0: device disconnected
[357545.353384] generic ttyUSB1: generic converter now disconnected from ttyUSB1
[357545.353418] usbserial_generic 3-2:1.1: device disconnected
[357547.504295] usb 3-2: new full speed USB device number 90 using ohci_hcd
[357547.709433] scsi243 : usb-storage 3-2:1.0
[357552.802636] usb 3-2: USB disconnect, device number 90
[357553.530963] usb 3-2: new full speed USB device number 91 using ohci_hcd
[357553.733118] usbserial_generic 3-2:1.0: generic converter detected
[357553.733398] usb 3-2: generic converter now attached to ttyUSB0
[357553.736119] usbserial_generic 3-2:1.1: generic converter detected
[357553.736392] usb 3-2: generic converter now attached to ttyUSB1
[357557.246208] usb 3-2: USB disconnect, device number 91
[357557.246614] generic ttyUSB0: generic converter now disconnected from ttyUSB0
[357557.246652] usbserial_generic 3-2:1.0: device disconnected
[357557.247006] generic ttyUSB1: generic converter now disconnected from ttyUSB1
[357557.247039] usbserial_generic 3-2:1.1: device disconnected
[357559.397622] usb 3-2: new full speed USB device number 92 using ohci_hcd
[357559.602744] scsi244 : usb-storage 3-2:1.0
[357564.697083] usb 3-2: USB disconnect, device number 92
[357565.440962] usb 3-2: new full speed USB device number 93 using ohci_hcd
[357565.643449] usbserial_generic 3-2:1.0: generic converter detected
[357565.643728] usb 3-2: generic converter now attached to ttyUSB0
[357565.646454] usbserial_generic 3-2:1.1: generic converter detected
[357565.646719] usb 3-2: generic converter now attached to ttyUSB1
[357569.156514] usb 3-2: USB disconnect, device number 93
[357569.156941] generic ttyUSB0: generic converter now disconnected from ttyUSB0
[357569.156978] usbserial_generic 3-2:1.0: device disconnected
[357569.157334] generic ttyUSB1: generic converter now disconnected from ttyUSB1
[357569.157366] usbserial_generic 3-2:1.1: device disconnected
[357571.307622] usb 3-2: new full speed USB device number 94 using ohci_hcd
[357571.512757] scsi245 : usb-storage 3-2:1.0
[357576.038221] usb 3-2: USB disconnect, device number 94

The thing is on two of my laptops the thing works out of the box. However, on third laptop it doesn't. On all the boxes I have done full system upgrade. So they are on the same version of software. Also, I am able to use another modem of different make and model, on the defaulting laptop using the same usb ports. So it should not be a hardware issue.

Further, I was under the impression, that USB modems are supported by usbserial kernel module. However, on the box on which this modem is working I have the following output (at the time when modem is working):

sudo lsmod | grep usb
usb_storage            35247  0 
btusb                   9889  2 
bluetooth             121489  23 rfcomm,bnep,btusb
usbhid                 31199  0 
hid                    65215  1 usbhid
scsi_mod              111801  6 usb_storage,uas,sg,sr_mod,sd_mod,libata
usbcore               119612  8 ehci_hcd,cdc_acm,usb_storage,uas,uvcvideo,btusb,usbhid

Is some other module, other than usbserial, responsible for managing USB modems? How do I find out which one is that?

Thanks for any help anybody can offer.

njoerd

Member

Registered: 2011-09-18

Posts: 6

Re: USB Modem not working

OK, slash_blog, here's part of my messages.log

Oct 15 14:52:16 localhost kernel: [    8.226955] usb 2-2.3: new high speed USB device number 5 using ehci_hcd
Oct 15 14:52:16 localhost kernel: [    8.341956] scsi7 : usb-storage 2-2.3:1.3
Oct 15 14:52:16 localhost kernel: [    8.408361] usbcore: registered new interface driver usbserial
Oct 15 14:52:16 localhost kernel: [    8.408374] USB Serial support registered for generic
Oct 15 14:52:16 localhost kernel: [    8.408412] usbcore: registered new interface driver usbserial_generic
Oct 15 14:52:16 localhost kernel: [    8.408414] usbserial: USB Serial Driver core
Oct 15 14:52:16 localhost kernel: [    8.458474] USB Serial support registered for GSM modem (1-port)
Oct 15 14:52:16 localhost kernel: [    8.458579] option 2-2.3:1.0: GSM modem (1-port) converter detected
Oct 15 14:52:16 localhost kernel: [    8.458743] usb 2-2.3: GSM modem (1-port) converter now attached to ttyUSB0
Oct 15 14:52:16 localhost kernel: [    8.458781] option 2-2.3:1.1: GSM modem (1-port) converter detected
Oct 15 14:52:16 localhost kernel: [    8.458896] usb 2-2.3: GSM modem (1-port) converter now attached to ttyUSB1
Oct 15 14:52:16 localhost kernel: [    8.458927] option 2-2.3:1.2: GSM modem (1-port) converter detected
Oct 15 14:52:16 localhost kernel: [    8.459066] usb 2-2.3: GSM modem (1-port) converter now attached to ttyUSB2
Oct 15 14:52:16 localhost kernel: [    8.459269] usbcore: registered new interface driver option
Oct 15 14:52:16 localhost kernel: [    8.459271] option: v0.7.2:USB Driver for GSM modems
Oct 15 14:52:16 localhost kernel: [    9.349960] scsi 7:0:0:0: Direct-Access     USBModem Disk             2.31 PQ: 0 ANSI: 2

and "lsmod | grep usb" gives

usb_wwan                9302  1 option
usbserial              31791  4 option,usb_wwan
usb_storage            44263  0 
usbhid                 35256  0 
hid                    81635  1 usbhid
scsi_mod              131546  6 uas,usb_storage,sg,sr_mod,sd_mod,libata
usbcore               142576  9 option,usb_wwan,usbserial,uas,usb_storage,usbhid,uhci_hcd,ehci_hcd

That's all: I use pppd for the connection, using /dev/ttyUSB2; works pretty much as described in the manuals.

hth