Bug 100091

Summary: cdc_acm / cdc_wdm issue. Connection to device lost (Sony Ericsson w660)
Product: Drivers Reporter: Fab Stz (fabstz-it)
Component: USBAssignee: Greg Kroah-Hartman (greg)
Status: RESOLVED INVALID    
Severity: high CC: fabstz-it
Priority: P1    
Hardware: x86-64   
OS: Linux   
Kernel Version: 4.0.2 Subsystem:
Regression: Yes Bisected commit-id:

Description Fab Stz 2015-06-18 07:08:49 UTC 
I use Gammu/Wammu to connect to my mobile phone (Sony Ericsson W660i)
With kernel 3.2 (debian wheezy) it works fine. But with kernel 3.16 (debian jessie) or even 4.0.2 it doesn't work.

Moreover, the connection of the phone to the PC makes some configuration changes on my phone. It changes my netwok connection type from "2G only" to "2G/3G" for obscure reasons

BTW, it seems the connection gets lost when the phone backlight turns off

Here is the dmesg when I connect the phone
[ 1536.912061] usb 3-2: new full-speed USB device number 2 using uhci_hcd
[ 1537.168027] usb 3-2: New USB device found, idVendor=0fce, idProduct=d0a3
[ 1537.168035] usb 3-2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 1537.168040] usb 3-2: Product: Sony Ericsson W660
[ 1537.168044] usb 3-2: Manufacturer: Sony Ericsson
[ 1537.168048] usb 3-2: SerialNumber: 3571550133112050
[ 1537.371402] cdc_ether 3-2:3.8 usb0: register 'cdc_ether' at usb-0000:00:1d.1-2, CDC Ethernet Device, 02:80:37:fa:02:00
[ 1537.371459] usbcore: registered new interface driver cdc_ether
[ 1537.380242] cdc_wdm 3-2:3.7: cdc-wdm0: USB WDM device
[ 1537.380282] usbcore: registered new interface driver cdc_wdm
[ 1537.382752] cdc_acm 3-2:3.1: ttyACM0: USB ACM device
[ 1537.387047] cdc_acm 3-2:3.3: ttyACM1: USB ACM device
[ 1537.389890] usbcore: registered new interface driver cdc_acm
[ 1537.389894] cdc_acm: USB Abstract Control Model driver for USB modems and ISDN adapters
[ 1537.424010] cdc_wdm 3-2:3.7: wdm_int_callback - 0 bytes
[ 1537.446697] cdc_ether 3-2:3.8 usb0: kevent 12 may have been dropped
Comment 1 Greg Kroah-Hartman 2015-06-18 14:47:25 UTC 
On Thu, Jun 18, 2015 at 07:08:49AM +0000, bugzilla-daemon@bugzilla.kernel.org wrote:
> https://bugzilla.kernel.org/show_bug.cgi?id=100091
> 
>             Bug ID: 100091
>            Summary: cdc_acm / cdc_wdm issue. Connection to device lost
>                     (Sony Ericsson w660)

Please send to the linux-usb@vger.kernel.org mailing list.
Comment 2 Fab Stz 2015-06-19 17:27:53 UTC 
Oh ! I just realized my mistake. Actually it is not the kernel that is faulty 
but my configuration (since I migrated from debian wheezy to jessie).

I had connection/disconnection issues because of conflicts between gammu and 
ModemManager.

It is also ModemManager which took the control of my phone and switched to 3G 
network.

Now that I disabled NetworkManager for my phone, I don't have such issues any 
more with kernel 3.16 or 4.0 (backlight still extincts, but that's by design 
for my phone)

Sorry for that.

Kind regards
Fab