FP4 and (unofficial) LineageOS

Not sure if this is LOS 20 related, but my FP4 isn’t detected in File Transfer mode no matter the computer I plug it on.

Definitely not a driver issue, as I’ve tested it on 4 different computers that do see my 2 others devices.

Funny thing is I can run adb/fastboot commands without any issue.
Photo storage mode is also working.

It appears really only File Transfer mode is somehow broken. I think this has appeared since I updated from LOS 19 to 20 but can’t be 100% sure as I do not use this mode very often. Anyone else experiencing this ?

@Aaanze just tested it here on my side. Works for me under Linux. Did you try another cable?

I assume you’re referring to microG Service Core? If so, yeah, I did. Aside from that, I also added FakeStore. SafetyNet check still yields CTS profile mismatch, unfortunately. I’ll try a few other options, though I might just end up switching to NikGApps.

I had the same issue happen to me recently; disabling USB debugging seems to have helped. Though this only occured once, on my Windows boot, where I haven’t enabled USB debugging since. On Linux it appears to mount properly either way.

Edit #1: Just tested it on a different machine running Windows. Results in the exact situation you described, with PTP working and file transfer (MTP) being broken. It seems Windows does not recognize the device as an MTP source when in ADB+MTP mode for some reason.

Edit #2: It seems it was a driver issue after all. When USB debugging and MTP are enabled, an unrecognized MTP device appears under “Other devices” in Device Manager with apparently no drivers available for it. To fix this, you need to select said device, and navigate to “Update driver” → “Browse my computer for drivers” → “Let me pick from a list of available drivers on my computer” → “Portable devices” → “(Standard MTP Device)” → “MTP USB Device”. Then click next and proceed against the warning. Windows should now correctly recognize your phone as an MTP device even with USB debugging enabled. As for why this occurs, I can’t really elaborate further.


This absolutely mind blowing.
How weird that multiple computers, simultaneously lose the ability to detect the device as MTP USB ?
This was so unlikely I didn’t even thought about checking the device manager. How silly of me…
Anway, thanks a lot :slight_smile:

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I wouldn’t say they lost the ability to detect it as an MTP source, rather the phone changed the USB data it reports to the computer upon connection.


More specifically:

  • the product ID for FP4 changes (from 0x4EE1 to 0x4EE2) when in ADB+MTP mode, thereby making the same USB MTP interface appear as a separate device;
  • additionally, in the same ADB+MTP mode, the bus driver fails to report a compatible ID of USB\MS_COMP_MTP for the MTP interface (possibly due to LOS 20 not providing enough data to Windows to classify it as such) which is required to identify the device as a viable candidate for the MTP driver (see line 37 of %SystemRoot%\System32\DriverStore\FileRepository\wpdmtp.inf_*_*\wpdmtphw.inf; INF files are used during device installation processes); or, alternatively, …
  • the MTP interface should have bInterfaceClass = 0x06, bInterfaceSubClass = 0x01, and bInterfaceProtocol = 0x01 (see line 38 of the same file), but in our case it has the values 0xFF, 0xFF, and 0x00, respectively.

Given the above, it seems reasonable that the MTP driver is not considered to be appropriate (since neither of the two conditions to do so are met) and the MTP interface is left untouched.

Now, to understand why the bus driver fails to report a compatible ID of USB\MS_COMP_MTP when USB debugging is enabled requires, I would imagine, at least a superficial understanding of the USB and MTP protocols, and their implementation within Windows and/or Linux. Neither of which I have, so my journey ends here.

If anyone’s interested, the sources:

  1. Overview of Device and Driver Installation - Windows drivers | Microsoft Learn
  2. USB Generic Parent Driver (Usbccgp.sys) - Windows drivers | Microsoft Learn
  3. Enumeration of USB Composite Devices - Windows drivers | Microsoft Learn
  4. Overview of INF Files - Windows drivers | Microsoft Learn
  5. INF Models section - Windows drivers | Microsoft Learn

The information above was obtained through Device Manager and USBView.

I suspect that your hunch about LOS 20 being the cause of this is correct, though.

Any time.


Good morning!
I’m still using LOS 19, but only because I didn’t have time to update.
Since I installed LOS (on my FP4 of course), I can’t receive SMS anymore.
Does anyone have any idea what this could be due to?
Thanks a lot!

I haven’t really an idea, but at least I can contribute some questions. :smiley:

Did you already try another messenger app? Sending SMS is working fine?

Have you been able to receive SMS with the FP4 using the original ROM or did you flash LOS immediately and had an Apple device before?

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Oh I had this one too !

I can’t really tell what I did, but eventually, it started working, like after a few days…

I did a lot of probably useless stuff such as clearing cache of the application, reflashing LOS, installing then uninstalling alternative SMS app, sending myself a lot of SMS from my own device…

And one morning… I received a whole bunch of SMS at once, and it started working.
Sorry for the imprecise answer, but that’s all I’ve got at this point.

Maybe you could also doublecheck if the phone number of your SMS central* is correct.

*don’t know want it is actually called in English.

Thanks a lot for all this answers. I’ll try to re answer them all in once.
I’m not sure whether I use the phone before I installed LOS or not. Sending SMS definitely works fine. So I think it’s not about the app.
I used LOS before on all my other phone and never had any problems.
@mapfeld How to check or set the number of the “SMS central”? I haven’t found anything related to that.

Using *#*#4636#*#*, you can enter the number entering the top option menu, wait a sending for the menu to load and scroll to the very bottom to the field labeled SMSC. Where this helped me earlier I just saw that I can send SMS without having anything set there.

Good morning!
The problem has been solved by my provider.
If this problem occurs again with someone else, here is the cause.
When I applied for the eSIM, I automatically got a contract with the Multicard option. But only one of these cards can receive SMS. The provider can set which of the cards should receive SMS.

Have a happy day everyone!


Hey @mapfeld,

sorry for the late reaction, I was quite busy in the last weeks.
I have the same issues with the newest build, I couldn’t update using OTA. I hadn’t the time to test flashing it manually, thanks for confirming flashing it via USB does not solve the issue. I will take the broken build offline & rebuild today.

PS: You probably discovered it already, but for others as well: You can configure your eSIM from my build.

Updated from the September 19.1 build to the current 20 build just fine. Did run into one thing which I thought I’d share: the update enabled the always-on display feature which I’d had disabled previously, and removed the toggle for it in settings (although weirdly it still shows up in search). There’s a quick settings tile called “Ambient display” that toggles it off, though.

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New build is up. Have a merry December!


Ufile.io - 1670690442

sha256sum lineage-20.0-20221210-UNOFFICIAL-FP4.zip recovery-20.0-20221210-UNOFFICIAL-FP4.img 
1d0114879460930344dfefb4d2c459fb75668d18dc6f42d6a7b82a15e3ca7cda  lineage-20.0-20221210-UNOFFICIAL-FP4.zip
46b4757184faf98bc3a0e16d5663276ff2ebac7a3c55e382ad0b199456136b79  recovery-20.0-20221210-UNOFFICIAL-FP4.img

Hmm after flashing I no longer have play services on my device… This is happening every update. What is going on?

Restarted and side-loaded mind the gapps again and this seemed to fix it?! Seems like something with google services gets wiped each time the OS is installed.

That’s normal, you should flash the OS update, reboot to recovery and then flash your Gapps package and any other addons you want.

Interesting, guess this is because of the new partitions? Was never the case when I had my OnePlus 6.

Thank you. Its run perfectly for me

hi there -

trying to build lineageos 20 for the fp4 via the microg4lineageos docker container, i keep running into these errors near the end of the build process:

frameworks/base/services/core/java/com/android/server/pm/ComputerEngine.java:1607: error: cannot find symbol
        Bundle metaData = p.getMetaData();
  symbol:   class Bundle
  location: class ComputerEngine
frameworks/base/services/core/java/com/android/server/pm/ComputerEngine.java:1663: error: cannot find symbol
                    mPermissionManager.getGrantedPermissions(ps.name, userId)
  symbol:   variable name
  location: variable ps of type PackageStateInternal
2 errors

is anyone else encountering this, and ideally could provide a fix?