I'm getting the original variant of this issue: my Huawei E3372 (vendor:device 12d1:14dc) works only if plugged in several times. Sometimes one replug is enough, sometimes three or even four.
I'm running Linux Mint 17.2, which is based on Ubuntu 14.04 LTS, so the issue is probably older than Ubuntu 15.10. This occurs on both the default 3.13 kernel and the updated 3.19 kernel (3.9.0-39-generic). Attached is the output of dmesg when the modem is plugged to the USB port, both in the failed and success cases. From what I can immediately see, the device ID is detected differently in these cases, so this might indeed have something to do with usb-modeswitch and not the kernel itself. When it fails, it seems the modem is detected as a CD-ROM, resulting in I/O errors. When it succeeds, there is no mention of a CD-ROM before the modem is detected as a HUAWEI_MOBILE. The read errors are surprising, since to my understanding these kinds of modems first usually identify themselves as a CD-ROM (to provide Windows drivers), before performing the switch to modem mode. One possible explanation would be a race condition: maybe usb-modeswitch sometimes attempts to perform the switch while the "CD-ROM" is being read, causing both the read to fail and the modem not to perform the switch correctly. Or maybe not. This probably needs an expert opinion :) ** Attachment added: "dmesg output of both failed and success cases" https://bugs.launchpad.net/ubuntu/+source/network-manager/+bug/1507957/+attachment/4562104/+files/dmesg-E3372.txt -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1507957 Title: Huawei E3372 LTE modem on 15.10 works only when connecting via wvdial and not network-manager To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/network-manager/+bug/1507957/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
