USB Modem stopped working on EOS 3.9.0

[Hafiz]

The previous EOS version works smoothly with USB Modem. The new edition does not properly work with the USB Modem.

We use 14 Laptop with Endless OS and use USB Modem. After upgrade EOS our modems dos not work properly. Have a solution yet? We are facing a work problem.eos-diagnostic-201121_104839_UTC+0600.txt (941.2 KB)

[jprvita]

I’m sorry you are experiencing this problem.

It looks like this same problem is happening on Ubuntu 20.10 as well, which uses the same kernel we use on EOS 3.9.0: https://bugs.launchpad.net/ubuntu/+source/usb-modeswitch/+bug/1903331. Despite what the title of the bug report indicates there, this problem does not seem to be related to usb-modeswitch, but somewhere in the kernel USB stack.

usb_modeswitch is doing its job and switching the dongle from device id 19d2:1595 to 19d2:1592. But then, some strange things happen:

1. ModemManager is not able to detect the SIM card in the modem:

Nov 21 10:42:23 asus ModemManager[359]: <warn>  Modem couldn't be initialized: Couldn't check unlock status: SIM not inserted
Nov 21 10:42:23 asus ModemManager[359]: <info>  Modem: state changed (unknown -> failed)
Nov 21 10:42:23 asus NetworkManager[366]: <info>  [1605933743.7732] manager: (ttyUSB0): new Broadband device (/org/freedesktop/NetworkManager/Devices/5)
Nov 21 10:42:23 asus NetworkManager[366]: <info>  [1605933743.7736] device (ttyUSB0): state change: unmanaged -> unavailable (reason 'managed', sys-iface-state: 'external')
Nov 21 10:42:23 asus NetworkManager[366]: <info>  [1605933743.7739] device (ttyUSB0): modem state 'failed'
Nov 21 10:42:23 asus NetworkManager[366]: <info>  [1605933743.7746] modem-broadband[ttyUSB0]: failed to retrieve SIM object: No SIM object available

2. Around 20s later, the USB device gets disconnected:

Nov 21 10:42:47 asus NetworkManager[366]: <info>  [1605933767.1702] device (usb0): state change: unavailable -> unmanaged (reason 'removed', sys-iface-state: 'removed')
Nov 21 10:42:47 asus kernel: usb 1-2: USB disconnect, device number 7
Nov 21 10:42:47 asus kernel: cdc_ether 1-2:1.0 usb0: unregister 'cdc_ether' usb-0000:00:14.0-2, ZTE CDC Ethernet Device

and then re-connected another 10s later:

Nov 21 10:42:54 asus kernel: usb 1-2: new high-speed USB device number 8 using xhci_hcd
Nov 21 10:42:55 asus kernel: usb 1-2: New USB device found, idVendor=19d2, idProduct=1595, bcdDevice= 0.00
Nov 21 10:42:55 asus kernel: usb 1-2: New USB device strings: Mfr=2, Product=3, SerialNumber=5
Nov 21 10:42:55 asus kernel: usb 1-2: Product: HSPA Mobile Broadband Station
Nov 21 10:42:55 asus kernel: usb 1-2: Manufacturer: HSPA,Incorporated
Nov 21 10:42:55 asus kernel: usb 1-2: SerialNumber: GPBANGDMF710MB01

There is a suspicion on the Ubuntu bug report that this may be caused by the USB power management feature in the kernel. Could you try to disable USB autosuspend by creating a file with the content bellow and then installing it on the affected machine at /etc/udev/rules.d/usb-power-HSPA_Mobile_Broadband_Station-19d2.1595.rules (let us know if you need extra help on how to perform that)? You should reboot the machine after installing that file.

# HSPA Mobile Broadband Station (19d2:1595)
ACTION=="add", SUBSYSTEM=="usb", ATTR{idVendor}=="19d2", ATTR{idProduct}=="1595", TEST=="power/control", ATTR{power/control}="on"

# HSPA Mobile Broadband Station after modeswitch (19d2:1534)
ACTION=="add", SUBSYSTEM=="usb", ATTR{idVendor}=="19d2", ATTR{idProduct}=="1534", TEST=="power/control", ATTR{power/control}="on"

# HSPA Mobile Broadband Station after modeswitch (19d2:1592)
ACTION=="add", SUBSYSTEM=="usb", ATTR{idVendor}=="19d2", ATTR{idProduct}=="1592", TEST=="power/control", ATTR{power/control}="on"

# HSPA Mobile Broadband Station after modeswitch (19d2:1596)
ACTION=="add", SUBSYSTEM=="usb", ATTR{idVendor}=="19d2", ATTR{idProduct}=="1596", TEST=="power/control", ATTR{power/control}="on"

# HSPA Mobile Broadband Station after modeswitch (19d2:1600)
ACTION=="add", SUBSYSTEM=="usb", ATTR{idVendor}=="19d2", ATTR{idProduct}=="1600", TEST=="power/control", ATTR{power/control}="on"

Please let us know if that solves the problem for you. If not, you can revert to the last version of Endless OS you had installed (3.8.7, per the attached logs) by running the following command on the terminal: sudo eos-rollback, entering your password and answering “yes” to the confirmation question, then waiting a few seconds for the program to finish, at which point you should see a message saying “Rollback complete”. After rebooting the computer would boot into the rollback version, and 3.9.0 will be kept as a rollback if you ever want to revert the process. If you go this route and it fixes the problem, please attach the eos-diagnostics file from the working version so we can see if it gives us any extra insights into the problem. Also, please note that when EOS 3.9.1 is out, your computer will get automatically updated to that version, but keep the “active” version (3.8.7, if you did the rollback) as a rollback option.

I know this is a lot of information, let me know if anything is not clear. And please let us know if any of this helps you solve or work around the problem.