05-06-2018 07:41 PM
I currently have T580 with pre-installed WWAN module (Fibocom L850-GL) and trying to get to work it on Linux. It works perfectly fine on Windows.
So far I discovered that Windows driver uses PCIe protocol to communicate with WWAN module, but Linux is supported apparently only through USB protocol, and if PCIe is enabled, the module ignores all USB commands according to its hardware specs document (page 26) - https://www.mev-elektronik.com/files/MEV%20Elektronik%20Service/produkt-downloads/rf-microwave-wirel...
Fibocom recommendation is to disable PCIe in BIOS, that is not supported by stock ThinkPad. Thus in Linux the device is only displayed as "Wireless controller: [0d40]: Intel Corporation Device 7360 (rev 01)" through lspci , and nothing on lsusb .
Any suggestions how to make it work on Linux?
As an alternative I'm considering getting another WWAN module, but it's quite likely it will not work due to whitelists. The only other module that is whitelisted for sure is L830-EB, that does not have global coverage and thus doesn't work in the US or China, even so it was reported that it's Linux-compatible (USB-mode only). Maybe there is a patched BIOS that has whitelists removed?
Wondering if there are Linux enthusiasts who are also looking for a way of using WWAN.
05-07-2018 12:23 AM
Do it well, worse becomes itself
05-07-2018 03:18 PM
cdc_mbim only supports USB devices and L850-GL disables USB altogether as described in "L850-GL Hardware User Manual" where they claim (in broken English) that for Linux/Android drivers "It must disconnect PCIe port, only keep USB connecting. If keep PCIe and USB connecting both,it needs disable PCIe by BIOS/UEFI of PC". As expected the module is only identified in Linux as a PCI-device, not a USB one, so CDC MBIM driver is useless in this case.
As there is no way of switching WWAN module to USB-only mode in stock ThinkPad BIOS, maybe it can be done through soldering out some pins on M.2 interface of the card?
05-07-2018 10:57 PM
Do it well, worse becomes itself
05-07-2018 11:25 PM
Pins from 41 to 54 that are used for PCIe, and none of them are used for USB.
It's described in Fibocom hardware specs (page 26-29): https://www.mev-elektronik.com/files/MEV%20Elektronik%20Service/produkt-downloads/rf-microwave-wirel...
In Windows it's displayed as PCI device on Port #3 - see the screenshot attached.
And finally on Linux it's displayed with lspci as "Wireless controller: [0d40]: Intel Corporation Device 7360 (rev 01)" on 00:03.0 as well.
So unfortunatelly I'm pretty sure that M.2 socket is connected to PCIe and it would be great if it can be disconnected somehow.
Maybe when T580 is ordered with antenna (as it's in my case) they change port layout during assembly...
05-16-2018 08:54 AM
Did you achieve any progress on this? I'm having a somewhat similar issue with a Linux-only T480s, but the WWAN device doesn't show up at all (at least not as anything I'd recognize as a broadband modem).
05-17-2018 02:03 AM
(Sorry for the double post, should have posted this here in the first place):
Thanks for shedding some light on this!
I have the same question for the WWAN offered on the T480s, namely:
Thanks for any answer.
05-17-2018 08:05 AM
Unfortunatelly, the only progress I was able achieve was to come back to Windows
As for identifying the device on Linux - it's should be somewhere in lspci, but not as a modem, so it took me a while to find it as well. It should be listed as a generic Intel 7360 device (it's based on Intel XMM 7360 chip).
05-17-2018 08:23 AM
1. EB version is only certified (supports LTE bands) for Europe. So it won't likely work in the US or China, South Africa, etc. GL version is truly global. People reported that EB version was working fine on Linux, since it's USB mode only.
2. No confirmed solution besides going back to Windows. You will need likely need to patch BIOS (no ready paches are available) to remove whitelists for BIOS. You can also patch WWAN firmware for Sierra Wireless WWAN carda (https://zukota.com) to get recongnized as whitelisted device. There is no guarantee it will work as well.
3. It's theoretically possible to disable PCIe protocol for M.2 connextor in unlocked BIOS, so not really an option. And another possibility is to solder out pins on the card that are responsible for PCIe interface, but again not sure it will automatically switch to USB mode in this case.
And finally if someone reverse-engineers Windows PCIe driver that might work one day. Don't think Fibocom will do anything since this chip already works on Linux if you plug it into unlocked motherboard/BIOS.
05-17-2018 08:23 AM
> Unfortunatelly, the only progress I was able achieve was to come back to Windows
I wish I could do that, if only to check if the device is really there, but our first order of business is to get rid of the preinstalled Windows and install Linux.
> As for identifying the device on Linux - it's should be somewhere in lspci,
> but not as a modem, so it took me a while to find it as well. It should be
> listed as a generic Intel 7360 device (it's based on Intel XMM 7360 chip).
Thanks for the quick reply. It doesn't for me (a few unknown/badly described devices in lshw/lspci/lsusb/dmidecode, but nothing even close to a broadband modem, nothing Intel, nothing Fibocom…), I'm beginning to suspect they forgot to install the device (although it's in the order description). I'll contact support when I'm back at work…