[ROM][UNOFFICIAL] LineageOS 17.1 for Unihertz Atom L (20200828)

[PeterCxy]

Introduction

This thread contains the LineageOS 17.1 custom firmware images for the Unihertz Atom L, a rugged Android phone released by Unihertz in July 2020, and the accompanying LineageOS Recovery used for flashing the firmware.

Please note that this ROM is one of my side projects, for which I could provide zero warranty. By installing this ROM, you acknowledge that you take all the risks that come with installing custom firmwares on your devices, including but not limited to bricking your device, losing your data, etc. You are always suggested to keep backups and make sure you know how to flash back to official ROM before trying any custom ROMs.

Please find the download links in the Download section. The following sections are guides to installing the ROM.

WARNING: DO NOT try to install this on Atom XL. This is ONLY for the Atom L.

Working Features

- All basic features (Telephony, VoLTE, Audio, Camera, NFC, WiFi, Bluetooth, ....)
- Programmable PTT (red) button (Functionality can be set in Settings - System - Buttons, under the "Search Button" section)
- 48MP camera seems to be working (unlike on many other super resolution devices)

Known Issues

- VoLTE is working (at least for me) but sometimes quirky. If you find it somehow stopped working, usually turning it off and back on again (in Settings - Network - Mobile Network) will fix it. Putting the device to SELinux Permissive mode also fixes most of the VoLTE quirks but this is not recommended (a few quirks in Enforcing mode is better than having the whole device Permissive)

Unlocking

1. Boot your Atom L to the official OS
2. Go into Settings - About phone, tap "build number" several times to enable developer settings
3. Go to Settings - System - Developer Settings, enable OEM unlocking and ADB debugging
4. Run `adb reboot bootloader` on your PC (there is no way to enter bootloader directly, only possible through adb)
5. Run `adb flashing unlock` and comfirm unlock on device (THIS WILL WIPE ALL DATA)
6. Reboot and now you should see an unlocked warning during boot screen.

Installing LineageOS Recovery

For now the only working recovery is the LineageOS Recovery, because the device's kernel does not load the touch driver in recovery mode for whatever reason, rendering TWRP useless.

1. Download `lineage_recovery_XXX.img` and `vbmeta.zip`, unpack `vbmeta.zip` to get three .img files starting with `vbmeta`
2. Run `adb reboot bootloader` to put your device in bootloader mode
3. Run `fastboot flash --disable-verification --disable-verity vbmeta vbmeta.img`
4. Run `fastboot flash --disable-verification --disable-verity vbmeta_system vbmeta_system.img`
5. Run `fastboot flash --disable-verification --disable-verity vbmeta_vendor vbmeta_vendor.img`
6. Run `fastboot flash recovery lineage_recovery_XXX.img`
7. Run `fastboot reboot recovery` to reboot into the newly-installed LineageOS Recovery

The LineageOS Recovery is operated by volume keys as selection and power as confirmation (or entering sub-menus). To return to upper levels of menus from sub-menus, press volume up until the selection goes to the first item and then disappears, then press power (i.e. there's a hidden "Go Back" item at the very top of each sub-menu).

The recovery will show a verification failed prompt for most packages that are not signed with the AOSP keys. This is safe to ignore.

Installing LineageOS 17.1

The LineageOS image must be installed via LineageOS recovery.

1. Download `lineage-17.1-Atom_L-XXX.zip`
2. Reboot your device into recovery (`adb reboot recovery` or simply hold volume up while turning power on)
3. Wipe all data (factory reset) (THIS DELETES EVEN INTERNAL STORAGE)
4. Choose Apply Update, then Apply Update from ADB
5. Run `adb sideload lineage-17.1-Atom_L-XXX.zip` from your PC
6. Wait for the process to finish. (The recovery might prompt something about verification failure, just ignore it and continue anyway)
7. At this point, you can then sideload the LATEST Magisk and OpenGAPPS Nano at your will (note that the size of the system partition might only be enough for the `nano` variant of OpenGAPPS) (If installing Magisk / OpenGAPPS fails, you can try rebooting into recovery again in advanced menus, then try installing them again)
8. Reboot into system and enjoy (Note that Magisk might cause your device to boot loop once or two but it will eventually boot)

When updating to a newer build, you have to flash the new zip, and then re-flash whatever mod you have installed previously (Magisk / GAPPS).

Download Links

LineageOS:
lineage-17.1-Atom_L-20200828-peter-signed.zip: https://mega.nz/file/bAgh1BZA#jzMs_0e9NUR9NcALXWp51ZeWttM5rl_3K5T8Or9hAW0
- Synchronized updates from LineageOS upstream.

lineage-17.1-Atom_L-20200728-peter-signed.zip: https://mega.nz/file/vBwlmL5D#wpw8RovBHyVFCLFlhQ2H5QAIb0ECXkT4of0FRijiP6A

LineageOS Recovery:
lineage_recovery_20200728.img: https://mega.nz/file/yc4Dnbyb#yx0Ci9p3q9_lfAiXkGfgWDFnRJI-JSGrv3kyawkU3fw

vbmeta:
vbmeta.zip: https://mega.nz/file/nF51mBoY#ZNY4j92wc_6a1dXch3l5r-w4VFl9QjN7YJaRMKRoEGk

XDA:DevDB Information
LineageOS 17.1 for Unihertz Atom L, ROM for the Android General

Contributors
PeterCxy
Source Code: https://cgit.typeblog.net/android/device/unihertz/Atom_L/

ROM OS Version: Android 10

Version Information
Status: Alpha

Created 2020-07-28
Last Updated 2020-07-28

 

[tvroman]

How different is the Atom XL?

Introduction

WARNING: DO NOT try to install this on Atom XL. This is ONLY for the Atom L.

Unfortunately I've got the XL version which I thought only varied from the L by the presence of a UHF radio! Can you explain to me why its not a suitable candidate for your mods which sound very good!?

And before you ask, I only got this radio for hacking so I don't mind experimenting if that is required. Please let me know if I can help.

The Bitfarmer

 

[PeterCxy]

Introduction

WARNING: DO NOT try to install this on Atom XL. This is ONLY for the Atom L.

Unfortunately I've got the XL version which I thought only varied from the L by the presence of a UHF radio! Can you explain to me why its not a suitable candidate for your mods which sound very good!?

And before you ask, I only got this radio for hacking so I don't mind experimenting if that is required. Please let me know if I can help.

The Bitfarmer

Because Unihertz publishes completely different firmware files for the L and XL, so the safest assumption is that there is more difference than just the UHF radio. If you want to risk it, then you CAN try using this ROM on the XL, as long as you know how to revert back to official if things go wrong. (But I cannot guarantee if the kernel image from L that this ROM uses will not cause serious issues like corrupted baseband or something on the XL)

My suggestion is that instead of trying this ROM directly on the XL, someone with XL can try to modify my device tree for L, replacing the kernel, dtbo images and other vendor blobs from the ones from XL, and then re-compile the ROM for XL. This would be the proper way to handle these two devices.

 

[a-dead-trousers]

Going XL

Hi.

Great work. :good:
I want to built a ROM for the Atom XL myself. And because I'm no expert on this (for now) I'm in search of guides and hints on how to achieve my goal.
As far as I know the biggest problem with Unihertz is that they use a Mediatek chipset with which they are not allowed to provide the sourcecode of the kernel. Or at least you have to pay for it from Mediatek.

But there are some variants of the chipset (Helio P60; mt6771) used in other mobile phones (e.g. Nokia X5) for which I was able to find kernelsources on Github. Using these and the latest Android kernel from google I tried to compile a kernel as a starting point. I was able to extract the build.config directly from the phone which helped tremendously. This should at least get me to the point where I'm able to assemble a TWRP build. But I believe that I'm still missing some (vital?) drivers which are specific to the actual device. This includes I think the missing touchscreen driver that you mentioned is preventing the recovery to be useful.

So now I'm a little bit stuck, because most of the guides to arrange a LineageOS (or any other custom ROM) build tree I found require the sourcecode from the manufacturer which we don't have. All other guides to build from scratch were too generic for my current level of expertise.

Can you please share your approach to create this build?
If you don't want to do this in the open you could also PM me.

With kind regards
ADT

 

[PeterCxy]

Hi.

Great work. :good:
I want to built a ROM for the Atom XL myself. And because I'm no expert on this (for now) I'm in search of guides and hints on how to achieve my goal.
As far as I know the biggest problem with Unihertz is that they use a Mediatek chipset with which they are not allowed to provide the sourcecode of the kernel. Or at least you have to pay for it from Mediatek.

But there are some variants of the chipset (Helio P60; mt6771) used in other mobile phones (e.g. Nokia X5) for which I was able to find kernelsources on Github. Using these and the latest Android kernel from google I tried to compile a kernel as a starting point. I was able to extract the build.config directly from the phone which helped tremendously. This should at least get me to the point where I'm able to assemble a TWRP build. But I believe that I'm still missing some (vital?) drivers which are specific to the actual device. This includes I think the missing touchscreen driver that you mentioned is preventing the recovery to be useful.

So now I'm a little bit stuck, because most of the guides to arrange a LineageOS (or any other custom ROM) build tree I found require the sourcecode from the manufacturer which we don't have. All other guides to build from scratch were too generic for my current level of expertise.

Can you please share your approach to create this build?
If you don't want to do this in the open you could also PM me.

With kind regards
ADT

You don't need the kernel source code to build a working ROM -- just look at my device tree for Atom L. I think you can build a working ROM for the XL by just replacing the prebuilt kernel in my device tree with the one from Atom XL and also re-extracting the vendor blobs from XL using the script in my devcie tree, then rename everything to Atom XL instead of L. I don't know if the integrated amateur radio would still work though.

 

[a-dead-trousers]

You don't need the kernel source code to build a working ROM -- just look at my device tree for Atom L. I think you can build a working ROM for the XL by just replacing the prebuilt kernel in my device tree with the one from Atom XL and also re-extracting the vendor blobs from XL using the script in my devcie tree, then rename everything to Atom XL instead of L. I don't know if the integrated amateur radio would still work though.

I'm already on to that.
But I seem to have trouble extracting the prebuilt kernel. None of the tools I found gave me the exact files you have got (dtb.img, dtbo.img, Image.gz). What did you use?
The best I could get were "dtb", "kernel" and "dtborecovery" (without extensions) which roughly had the same size as yours.
Also, as far as I understand it, with your initial commit (without the modifications for Lineage itself) I should be able to at least compile a recovery image but I got an error regarding a missing dtb.img file in the "out" directory.
Something seems to be missing because, my dtb file is in the "device" directory and not being transfered into "out" during building.
I'm not sure that is because I have got a different naming scheme (renamig it didn't help) or I did something wrong with the extraction.

---------- Post added at 07:30 ---------- Previous post was at 07:14 ----------

Another question I have:
Are the vbmeta-files you used to flash the recovery the ones from the original firmeware zip from unihertz or did you get them from the lineage built?

And reguarding the rather smallish system partition:
I have an idea to bypass that by using the SPFlash Tool from Mediatek. As far as I understand the settings in the scatter-file this tool does a repartitioning of the internal storage. So we only need to "decrease" the userdata, "move" some partitions inbetween and "increase" the system. Only problem is, I couldn't find a partition designated as "system" in the scatter-file, only one big "super" and a "vbmeta-system" (which for my understaning is for verified boot) partition.
What do you think?

 

[PeterCxy]

I'm already on to that.
But I seem to have trouble extracting the prebuilt kernel. None of the tools I found gave me the exact files you have got (dtb.img, dtbo.img, Image.gz). What did you use?
The best I could get were "dtb", "kernel" and "dtborecovery" (without extensions) which roughly had the same size as yours.
Also, as far as I understand it, with your initial commit (without the modifications for Lineage itself) I should be able to at least compile a recovery image but I got an error regarding a missing dtb.img file in the "out" directory.
Something seems to be missing because, my dtb file is in the "device" directory and not being transfered into "out" during building.
I'm not sure that is because I have got a different naming scheme (renamig it didn't help) or I did something wrong with the extraction.

---------- Post added at 07:30 ---------- Previous post was at 07:14 ----------

Another question I have:
Are the vbmeta-files you used to flash the recovery the ones from the original firmeware zip from unihertz or did you get them from the lineage built?

And reguarding the rather smallish system partition:
I have an idea to bypass that by using the SPFlash Tool from Mediatek. As far as I understand the settings in the scatter-file this tool does a repartitioning of the internal storage. So we only need to "decrease" the userdata, "move" some partitions inbetween and "increase" the system. Only problem is, I couldn't find a partition designated as "system" in the scatter-file, only one big "super" and a "vbmeta-system" (which for my understaning is for verified boot) partition.
What do you think?

> None of the tools I found gave me the exact files you have got (dtb.img, dtbo.img, Image.gz). What did you use?

There is a tool called `unpack_bootimg` in the Android source code. Just run `make unpack_bootimg` in the root directory of the Android source tree and you will get one in the output directory. (btw I have renamed those extracted files so the names won't exactly match, but you need this tool to extract the correct images. All other tools won't work properly).

> my dtb file is in the "device" directory and not being transfered into "out" during building.

Because most tools other than `unpack_bootimg` extracts dtb incorrectly.

> Are the vbmeta-files you used to flash the recovery the ones from the original firmeware zip from unihertz or did you get them from the lineage built?

Those don't matter. Either will work as long as you flash it with the correct parameters as given in my post.

> And reguarding the rather smallish system partition

No don't do that. Android 10 does not use a separate system partition anymore, instead both system, vendor and product are sub-partitions in a huge super partition. When flashing a new ROM, the partitions are automatically resized to match the new image exactly, instead of leaving free space unused like before Android 10. That's why I need to reserve space in BoardConfig.mk for gapps to be installed correctly.

 

[a-dead-trousers]

Still not able to build.

There is a tool called `unpack_bootimg` in the Android source code. Just run `make unpack_bootimg` in the root directory of the Android source tree and you will get one in the output directory. (btw I have renamed those extracted files so the names won't exactly match, but you need this tool to extract the correct images. All other tools won't work properly).

I'm still getting an error:

FAILED: ninja: 'out/target/product/Atom_XL/dtb.img', needed by 'out/target/product/Atom_XL/boot.img', missing and no known rule to make it

Comparing your BoardConfig.mk with mine shows a slight difference in the offset and size values which could be associated with the different kernels of the phones.
But using "unpack_bootimg" I didn't get a value for "BOARD_KERNEL_OFFSET" like you have it in your config. Could this be the problem?
Your BoardConfig.mk
My BoardConfig.mk
Do you see anything else out of the ordinary?
(Because I'm doing everything what you did step-by-step the links point to the best matching commits)

Despite not being able to compile right now I tried to press on with integrating your changes in the hopes that it will be fixed somehow later on
So I'm currently stuck on this commit of yours:
Atom_L: import overlay from official vendor
Where did you get the "config.xml" and "power_profile.xml" from? The best thing I could find was a "power_profile.xml" inside "/vendor/overlay/FrameworkResOverlay/FrameworkResOverlay.apk" which seems to be a "compiled" version of the aforementioned xml-file.

 

[PeterCxy]

I'm still getting an error:

FAILED: ninja: 'out/target/product/Atom_XL/dtb.img', needed by 'out/target/product/Atom_XL/boot.img', missing and no known rule to make it

Comparing your BoardConfig.mk with mine shows a slight difference in the offset and size values which could be associated with the different kernels of the phones.
But using "unpack_bootimg" I didn't get a value for "BOARD_KERNEL_OFFSET" like you have it in your config. Could this be the problem?
Your BoardConfig.mk
My BoardConfig.mk
Do you see anything else out of the ordinary?
(Because I'm doing everything what you did step-by-step the links point to the best matching commits)

Despite not being able to compile right now I tried to press on with integrating your changes in the hopes that it will be fixed somehow later on
So I'm currently stuck on this commit of yours:
Atom_L: import overlay from official vendor
Where did you get the "config.xml" and "power_profile.xml" from? The best thing I could find was a "power_profile.xml" inside "/vendor/overlay/FrameworkResOverlay/FrameworkResOverlay.apk" which seems to be a "compiled" version of the aforementioned xml-file.

> Comparing your BoardConfig.mk with mine shows a slight difference in the offset and size values which could be associated with the different kernels of the phones.

TARGET_KERNEL_OFFSET should normally always be 0x00008000. Also, your other offset values seem to be wrong too -- those values from `unpack_bootimg` cannot be filled in directly to BoardConfig.mk. Instead, you need to subtract BOARD_KERNEL_BASE from them (e.g. BOARD_RAMDISK_OFFSET should be 0x55000000 - 0x40078000, which is 0x14f88000, the same as mine). In fact, I think those parameters should be exactly the same for XL and L. Other than that, I don't think I can see much of a problem about your makefiles.

However, note that not all of my historical commits represent a compilable state of the device tree. I'd suggest you start directly from the latest state and just replace whatever is relevant instead of starting over. And there should not be much that needs changing at all except device names, fingerprints and the proprietary vendor files.

> Where did you get the "config.xml" and "power_profile.xml" from

Exactly from those apks. Just decompile them using apktool.

 

[a-dead-trousers]

TARGET_KERNEL_OFFSET should normally always be 0x00008000. Also, your other offset values seem to be wrong too -- those values from `unpack_bootimg` cannot be filled in directly to BoardConfig.mk. Instead, you need to subtract BOARD_KERNEL_BASE from them (e.g. BOARD_RAMDISK_OFFSET should be 0x55000000 - 0x40078000, which is 0x14f88000, the same as mine). In fact, I think those parameters should be exactly the same for XL and L. Other than that, I don't think I can see much of a problem about your makefiles.

Still giving me errors.
So I tried a very unconventional approach: I just copied the file myself into the mentioned "out/target/product/Atom_XL" folder.
For now it's still compiling. Fingers crossed.

However, note that not all of my historical commits represent a compilable state of the device tree. I'd suggest you start directly from the latest state and just replace whatever is relevant instead of starting over. And there should not be much that needs changing at all except device names, fingerprints and the proprietary vendor files.

I just reached your biggest commit yet.
Can you tell me how you got the list of needed files? I hope it's not through trial-and-error.
Except for the values in "setup-makefiles.sh" only the "proprietary-files.txt" seems to be device specific. Is there anything else I need to be aware of in this commit?

P.S.: I know it is tedious to go through your commits one by one but I want to learn something of it not just simply copying what you did. To get a feeling where the biggest pitfalls are and what you did to circumvent them.

 

[PeterCxy]

Still giving me errors.
So I tried a very unconventional approach: I just copied the file myself into the mentioned "out/target/product/Atom_XL" folder.
For now it's still compiling. Fingers crossed.

I just reached your biggest commit yet.
Can you tell me how you got the list of needed files? I hope it's not through trial-and-error.
Except for the values in "setup-makefiles.sh" only the "proprietary-files.txt" seems to be device specific. Is there anything else I need to be aware of in this commit?

P.S.: I know it is tedious to go through your commits one by one but I want to learn something of it not just simply copying what you did. To get a feeling where the biggest pitfalls are and what you did to circumvent them.

> Still giving me errors.

Looks like that dtb.img error was totally my fault -- it was due to my jerry-rigged solution of using prebuilt dtb image that conflicted with one of Lineage's update in August and I haven't built the ROM for a month. Now I have fixed it in the latest commit.

> Can you tell me how you got the list of needed files?

All of those files are for VoLTE support and I started with the list from a commit in Redmi Note 7 Pro's device tree that imported those VoLTE blobs, and then added what was missing one by one (when something is missing the Phone process will crash and you can see what got missing in the logs). I don't think the list will be any different on Atom XL so you can just use the one in my device tree.

 

[a-dead-trousers]

Hi.
Thanks to you everything is running smoothly here. But what bugs me is that TWRP is not working on our devices.
Although for the Atom there is a possibility: https://forum.xda-developers.com/android/development/twrp-modded-to-unihertz-atom-t3885793
Before I want to go public with my build I wanted to solve this last "mystery".

So I tried to include it in my current source tree according to the (official?) guide but some errors prevented me from a successful build.
Naturally I asked for some guidance at the most reasonable places I know of but got nothing so far:
https://forum.xda-developers.com/showpost.php?p=83443611&postcount=4622
https://forum.xda-developers.com/showpost.php?p=83455271&postcount=4623
https://github.com/TeamWin/android_bootable_recovery/issues/70
I even tried different repositories (omnirom/android_bootable_recovery) and revisions (android-9.0) but these resulted in missing library "type" (static vs. shared) errors so I assume these are too old for LineageOS 17.1

What I want to know is how you managed to get TWRP to built for your device even though the touchscreen wasn't working?
Did you use your LineageOS source tree or one of the many "minimal" manifests? If so, which one would be the "best" to use?

wkr ADT

 

[dirtylimerick]

@PeterCxy and @a-dead-trousers

Thanks for all the work on this so far. I've got an Atom L and have gotten the ROM's PeterCxy posted running on them as in the OP. Do either of you have a quick step-by-step workflow of how you got all the Lineage sources set up and built into the various ROMs? I'd like to be able to build the ROMs from scratch and understand the process.

If I can get caught up to where you two are at with the builds, I can help debug, test and work through issues.

 

[a-dead-trousers]

[MENTION=5351691] Do either of you have a quick step-by-step workflow of how you got all the Lineage sources set up and built into the various ROMs? I'd like to be able to build the ROMs from scratch and understand the process.

If I can get caught up to where you two are at with the builds, I can help debug, test and work through issues.

I documented my steps to setup up the build environment in the readme of my repo:
https://github.com/ADeadTrousers/android_device_Unihertz_Atom_XL
But leave out the TWRP part. It isn't working yet mostly because TeamWin/android_bootable_recovery and LineageOS/android_bootable_recovery are too similar.
To figure out all the bits and pieces needed for the device I followed the commit log of @PeterCxy build.

 

[a-dead-trousers]

Hi, @PeterCxy.

Finally I was able to build a TWRP recovery and surprise, surprise the touchscreen isn't working.
But during my attempts to get a working TWRP build I came acros a guide that explains how to patch the kernel to get the touchscreen to work.
https://forum.hovatek.com/thread-27132.html
So I tried to follow it but failed to identify the "end" of the zipped Image-file (step 18) to remove the payload from the gz-file. Regardless of which of the null-bytes I use for cutting I always get a warning from 7-zip that there is still data at the end.
Do you know a better approach to achieve this whole patching? Maybe even come up with a scripting solution to easily apply this patch in later builds?

wkr ADT

 

[PeterCxy]

Hi, @PeterCxy.

Finally I was able to build a TWRP recovery and surprise, surprise the touchscreen isn't working.
But during my attempts to get a working TWRP build I came acros a guide that explains how to patch the kernel to get the touchscreen to work.
https://forum.hovatek.com/thread-27132.html
So I tried to follow it but failed to identify the "end" of the zipped Image-file (step 18) to remove the payload from the gz-file. Regardless of which of the null-bytes I use for cutting I always get a warning from 7-zip that there is still data at the end.
Do you know a better approach to achieve this whole patching? Maybe even come up with a scripting solution to easily apply this patch in later builds?

wkr ADT

There is no sane way to solve the problem without kernel source code. Basically the stock kernel just does not load the touch screen driver in recovery mode. That patching guide is pretty out of date and I imagine it won't work on most recent kernels. The only proper way is to pressure Unihertz to actually obey GPLv2 and release their kernel source code. Or maybe someone can try reverse-engineering the kernel, but at least I won't do it because it'll just be too much of a hassle.

 

[a-dead-trousers]

There is no sane way to solve the problem without kernel source code. Basically the stock kernel just does not load the touch screen driver in recovery mode. The only proper way is to pressure Unihertz to actually obey GPLv2 and release their kernel source code.

I'm with you on this one, but as long as we don't have the source code we need to resort to other means to achieve our goals.

That patching guide is pretty out of date and I imagine it won't work on most recent kernels.

Yeah it's from way back in 2019
Anyway, with a little bit of tinkering I was able to modify my kernel to load the touchscreen driver in recovery mode.
Here is the device tree and the manifest i used.
I wouldn't recommend to use it in it's current state at all though because the fstab needs a little bit of tinkering. Everything seems to be either unordered or not mounted properly and I fear anything you do in there now will mess up the whole device. BUT I got the touchscreen goin for me which is nice.

Or maybe someone can try reverse-engineering the kernel, but at least I won't do it because it'll just be too much of a hassle.

As soon as I have everything sorted out that needs to be fixed on my build (e.g. signing, radio, included gapps working properly, TWRP) I want to dig deeper into the kernel.
There are some devices with Helios P60 out there from other vendors which offer kernel sources.

P.S.: I also uploaded a HOW-TO in my device tree.
If you or someone else wants to try it. Also if you want to you can send me a "symbl.txt" (see to the HOW-TO) extracted from your device then I can do the patching for the Atom_L too.

 

[PeterCxy]

I'm with you on this one, but as long as we don't have the source code we need to resort to other means to achieve our goals.

Yeah it's from way back in 2019
Anyway, with a little bit of tinkering I was able to modify my kernel to load the touchscreen driver in recovery mode.
Here is the device tree and the manifest i used.
I wouldn't recommend to use it in it's current state at all though because the fstab needs a little bit of tinkering. Everything seems to be either unordered or not mounted properly and I fear anything you do in there now will mess up the whole device. BUT I got the touchscreen goin for me which is nice.

As soon as I have everything sorted out that needs to be fixed on my build (e.g. signing, radio, included gapps working properly, TWRP) I want to dig deeper into the kernel.
There are some devices with Helios P60 out there from other vendors which offer kernel sources.

P.S.: I also uploaded a HOW-TO in my device tree.
If you or someone else wants to try it. Also if you want to you can send me a "symbl.txt" (see to the HOW-TO) extracted from your device then I can do the patching for the Atom_L too.

Happy to hear that you were able to figure the touchscreen out. I tried to port TWRP at the very beginning when I started tinkering with the device but quickly grew frustrated and just ported Lineage Recovery instead. I guess I might try patching the kernel image too at some point later.

BTW, for TWRP to work with devices released after Android 10, I'm pretty sure you need an extra set of patches that are not yet fully merged to the main TWRP repository. I remember there's some guy providing another manifest with all the patches applied but I couldn't remember the name.

 

[a-dead-trousers]

Hi.

I just officially announced my build for the Atom XL:
https://forum.xda-developers.com/android/development/rom-lineageos-17-1-unihertz-atom-xl-t4171407
Could you please put a link in your first post for those in search of the Atom XL and found your thread instead. Thanks.

wkr ADT

 

[a-dead-trousers]

hi @PeterCxy.

During my daily usage of the phone I encountered a strage problem:
The audio jack isn't working. Plugging in some headphones I get this slight click in the earpieces when the circuits connect but nothing else happens. Neither a "headphone" icon in the status bar nor hearing anything coming from the headphones itself. The main speaker of the phone keeps playing the music. Using bluetooth everything is working as expected though. So I used logcat to see if something is coming up during plugging in but nothing "catchy" shows up in the logs. My guess is that some (vendor?) service is missing or not started during booting. Next I checked If something shows up on logcat during boot but I'm not sure for what to look exactly. There are quite a few errors and warnings though. In my despair I started to "fix" the "avc: denied" (SEPolicy) entries. Thats when I found a specific error reguarding VoLTE. Maybe this would fix the problems you had with VoLTE in enforcing mode:
https://github.com/ADeadTrousers/an..._Atom_XL/blob/master/sepolicy/private/init.te
(The line with "socket_device:sock_file")
My provider doesn't support VoLTE so I'm not sure if this helps or not. Maybe you could check it.

Anyway can you please tell me if your device's audio jack is working or not?
If you're (by some mysterious coincidence) not affected by this, can you at least give me some pointers for what to look for to get this fixed on my side.
The Internet Is not very helpful when searching for "android audio jack" or something similiar.
Thanks in advance.

wkr ADT