Comment 38 for bug 363812

The thinkpad-acpi upstream maintainer here.

If the module does not show up in lsusb (run as *root*), it is blocked by the thinkpad firmware (powered down).

It will be powered down by the firmware if *any* of the following conditions are met:

1. Set to hidden, radio blocked or something like that in the BIOS setup screens (usually cannot be reenabled by software until reconfigured in BIOS);

2. Disabled in software, and not re-enabled (warning: this state *IS* kept across reboots and power down). In this case, thinkpad-acpi is supposed to be able to re-enable the device, if you use the rfkill sysfs class to do it;

3. Radio-kill physical switch is enabled (i.e. radios are killed). NOTHING can reenable the device until you disable the radio-kill switch. Mind you, I have been told there are kernel bugs in this area for some WLAN devices, but I haven't heard of any on the WWAN devices;

4. The kernel rfkill subsystem orders thinkpad-acpi to kill the radio (check /sys/class/rfkill/*), which it can do at any time, for any reason;

5. Broken backports of the rfkill subsystem, or other kernel bugs.

So, please check if any of these conditions are the issue, and do a full checking of the rfkill behaviour to make sure there are no problems with the rfkill subsystem. The thinkpad-acpi driver will log a lot of information if properly compiled with the THINKPAD_ACPI_DEBUG Kconfig option enabled, and loaded with the "debug=0xffff" parameter.