Fibocom L850-GL hangs upon connect.

[Vincent Bernat]

 ❦ 16 août 2018 11:18 +0200, Aleksander Morgado <aleksander at aleksander.es>:

>>>> If this modem is going to end up stuck with pure PPP and therefore maxing
>>>> out at 25Mbps, then I'm not too concerned anyways since its use is rather
>>>> limited. I just wish I could figure out how to switch this thing to MBIM
>>>> (Tried everything listed in the AT Command reference guide, including
>>>> factory resets and defaults.).
>>>>
>>>
>>> Talked to Fibocom engineers and unfortunately that firmware version
>>> you're using cannot do MBIM :/
>>
>> On the latest Lenovo X1/T580/T480, this modem is plugged on a
>> PCIe-enabled M2 port and boots as a PCI device. It seems Linux isn't
>> able to handle that. People tried to tape the PCIe pins to make it boot
>> as USB, but it's then blacklisted in the BIOS. Maybe you have some hints
>> on how to make this modem switch to USB after booting?
>>
>> I don't own one yet, so I cannot really help with the specifics.
>>
>> Relevant thread:
>>  https://forums.lenovo.com/t5/Linux-Discussion/Linux-support-for-WWAN-LTE-L850-GL-on-T580-T480/m-p/4067969
>
> Fibocom engineers say there is no way to "switch" to USB after the
> device has been booted in PCIe mode. Was told that Intel may be
> already working on the PCIe support for these devices in the kernel,
> but while that is not a reality, there seems to be absolutely no way
> to handle the device in the Thinkpad running Linux, unless Lenovo
> decides to add the corresponding USB vid:pid in the BIOS whitelist.

Thanks for the heads up!
-- 
Don't stop at one bug.
            - The Elements of Programming Style (Kernighan & Plauger)