[UNOFFICIAL][ROM]ALPHA LineageOS 19.1 for Galaxy Tab A [SM-T550] Sept 12, 2022

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retiredtab

Senior Member
Nov 16, 2017
1,239
815
PLEASE BEFORE YOU decide to try this rom, you MUST read all of post 1, 2, 3 and 4 (about 10 minute read). If you think this is an unreasonable request, then stop reading now and find another rom. Thank you.

I am not responsible for lost data, identity theft, lost money, security vulnerabilities, bricked devices or any other hardware or software malfunctions that comes as a result of flashing this rom.

BACKUP YOUR DATA AND OLD rom BEFORE trying my rom.

If you are NOT an expert in using fastboot, adb, odin, heimdall, twrp, DO NOT use this rom. You must know how to use these tools to revert back to your old rom.

If you are new to flashing custom roms, do NOT attempt this.

If you need your tablet for work and something important, do NOT flash this rom. This rom could result in a bricked device or boot loop or non booting device or you not being able to revert back to your old rom.

What works

1. bluetooth
2. wifi
3. brightness
4. external audio
5. GPS
6. audio through headphone jack
7. audio over bluetooth
8. camera

What doesn't work

1. selinux is permissive. I have tried to make this build enforcing for weeks, but when I do, the OS doesn't boot and there is no adb logcat output despite making an "eng" build. Without adb logcat output, it's virtually impossible to determine what is wrong and I'm not spending anymore time on it. If having enforcing mode is important to you, use my 18.1 builds.

2. keyboard bug workaround. When prompted to enter something like a Bluetooth pin or text based password, sometimes the keyboard is not shown on the screen or off screen. The workaround is to goto settings, system, languages & input, on-screen keyboard, Android Keyboard (AOSP), appearance & layout, theme and choose "Material - follow system settings".

This keyboard bug is a LineageOS bug as per

https://review.lineageos.org/c/LineageOS/android_packages_inputmethods_LatinIME/+/325438

3. gapps. Some of you require gapps for whatever reason. I use Aurora Store for my purposes and thus have NO KNOWLEDGE of the current state of gapps.

There are various gapps projects (at least 5 in 2022). Each has pros and cons. It's your job to do the research and find a suitable gapps project. I suggest you allocate at least a couple of hours doing your own research. My rom works by itself fine without gapps. DO NOT talk about gapps in this thread. As a courtesy to gapps users, if you want to talk about gapps, I have opened a new thread at

https://forum.xda-developers.com/t/...m-t35x-sm-t550-sm-t560nu-and-sm-p550.4479285/

so you may discuss gapps wrt to the msm8916 platform. I will NOT be participating in that thread as I do NOT use gapps.

Thanks

1. LineageOS team for source code.

2. Kyle Harrison
- looking through the adb logcat and suggesting that my binder code was too old to work with Android 12's keystore2 code
- for the graphics and legacy camera patches to allow msm8916 to work with Android 12
- for his Motorola LineageOS 19.1 device trees so I could use his patches as a template for msm8916

3. @tarkzim
- adding back audio hal 2.0 and legacy camera hal 1.0 into the LineageOS trees
- helping me think through the msm8916 random reboots which was due to the TCP/IP patches
- maintaing and updating his repos so I can study them for learning purposes

4. pre ALPHA testers @breversa , @XDA_username00 for willing to test pre ALPHA builds and leaving feedback.
 
Last edited:

retiredtab

Senior Member
Nov 16, 2017
1,239
815
FAQ - I spent hundreds of hours building this rom. It was frustrating process from Nov 2021 to Aug 2022 running into bug after bug. The least you can do is spend a few minutes reading everything before posting.

Q1. Where are the source and kernel source files?
A1. The kernel source files are at

https://github.com/retiredtab/android_kernel_samsung_msm8916

The device tree files are at

https://github.com/retiredtab/android_device_samsung_msm8916-common/tree/lineage-19.1
https://github.com/retiredtab/android_device_samsung_gt510wifi/tree/lineage-19.1
https://github.com/retiredtab/device_samsung_gte-common/tree/lineage-19.1

The vendor tree files are at

https://github.com/retiredtab/android_vendor_samsung_gt510wifi/tree/lineage-19.1
https://github.com/retiredtab/vendor_samsung_msm8916-common/tree/lineage-19.1

The manifest.xml (or roomservice.xml) and build instructions for 19.1 are at

https://github.com/retiredtab/LineageOS-build-manifests

Q2. Is this ALPHA rom suitable as a daily driver?
A2. It can be depending on your requirements. I can't test every app so you try it yourself to see if it's suitable. I've been using this rom myself since mid March 2022 with no major issues. I suggest you do a clean install, see FAQ 11, and flash this 19.1 ROM BY ITSELF (no gapps, magisk, etc) and see if you like it. If you do like it and want to add gapps then see FAQ 12.

Q3. What if my app, xyz, doesn't work?
A3. If your app doesn't work, then go back to your old rom.

Q4. Your rom is laggy and buggy.
A4. If you find the above, then go back to your old rom. There's only so much software can do on a 2015 budget level tablet. Remember a budget tablet will have the slower SoC/CPU and less DRAM than a top of the line model. Your tablet will also run slower when you use gapps. You can run a lot of software without using gapps. Research fdroid, newpipe, Aurora store etc.

Q5. What TWRP should I use?
A5. You MUST use TWRP 3.5.2_9. Get it from

https://dl.twrp.me/gt510wifi/

Q6. Why should I use this rom?
A6. If you don't like this rom, then don't use it.

Q7. Will you offer monthly updates with security patches?
A7. I will try to offer monthly security patches, but that all depends on if I continue to have high speed Internet in the future.

Q8. Can you help me? I'm a newbie. Can you provide step by step instructions?
A8. I don't have the time to help newbies, so please do your own research. There are lots of tutorials, videos, etc on how to flash roms. Newbie questions must be posted in the Questions and Answers forum, not here.

Q9. Can I report a bug with respect to the rom?
A9. Yes, but you need to supply the following information. If you don't, I won't look at it.

You must provide an adb logcat of the problem and tell me how to reproduce it. Note I will not be downloading any apps that require money or an userid/password. For example, if you have problems with Netflix, I cannot help you since I don't have a paid subscription. If you use some app that requires an userid/password, I cannot help you as I'm not willing to create another userid/password even if it's free.

To get a logcat, open up a terminal window.
Code:
# clear the logcat first
adb logcat -c
# start logcat trace
adb logcat > problem.txt
# reproduce problem
# wait until problem has occured, then stop trace by hitting ctrl-c
# attach the problem.txt ZIPPED as text files don't seem to get attached properly

Q10. Will you still build 18.1 for this device?
A10. Yes, for rest of 2022, but I will make a decision in January 2023 on how 18.1 and 19.1 will be maintained. If you like to help by building 18.1/19.1, please let me know.

Q11. Do I need to erase everything and format my data?
A11. Yes, you MUST erase all the partitions (system, data, dalvik/art cache, cache) using TWRP and MUST format your data before installing 19.1 when you are coming from stock or an earlier version of LineageOS or from another custom rom. If you get stuck at the boot animation for more than 5 minutes, it's likely because you didn't follow the instructions I just wrote. Dirty flashes from stock, other custom roms or older LineageOS versions are not supported and not likely to work.

Q12. What gapps should I use?
A12. I don't use gapps anymore. I use Aurora Store. As of Nov 6, 2021, I no longer make recommendations on which gapps to use as your mileage may vary.

Let me by crystal clear. YOU NEED TO DO YOUR OWN HOMEWORK selecting between the various gapps offered. There are 5: opengapps, nikgapps, mindthegapps, flamegapps and bitgapps. Each one will have it's own installation instructions. The only recommendation I will offer to use the SMALLEST version of gapps.

Don't be surprised that whatever gapps you use might have problems like "Just a sec", voice not working, updating google play store please wait, etc. These are NOT problems of the OS as the OS will run fine without gapps. These are gapps problems and you must ask in the gapps forum why it doesn't work.

In addition, some of the gapps may not install properly when using TWRP and say "cannot /mnt/system". For those cases, please use the LineageOS recovery.img you can download from

https://sourceforge.net/projects/retiredtab/files/SM-T550/LineageOS-recovery/

By flashing the LineageOS recovery.img, it will overwrite the existing TWRP and you will get a different UI.

Q13. I'm having problems with gapps, can you answer why it's not working?
A13. I WILL NOT answer any questions regarding gapps. This thread is about the rom, not gapps. Android does not depend on gapps in order to work.

Questions about gapps, for your courtesy, should be asked at

https://forum.xda-developers.com/t/...m-t35x-sm-t550-sm-t560nu-and-sm-p550.4479285/

Q14. Why isn't my post answered or ignored?
A14. Questions already answered in the FAQ will be completely ignored. Again, I do not use Windows OS or gapps.

Q16. What speed up/optimization tips do you suggest?
A16.

1. Turn off animations. Go into developer settings, scroll down to the drawing section, and set window, transition and animator scale all to "off".
2. If you don't have a google account, don't install gapps. Use Aurora Store to get your apps as you can get all the same apps from the play store using an anonymous login.
3. Dont' run more than 2 apps at the same time. You can probably listen to music in the background and use a web browser at the same time, but don't expect great performance from a 2015 entry level tablet.
4. Use a web browser like Brave that has built in adblock and privacy features.
5. Use newpipe to watch your streaming content. It has built in adblock so you don't have to watch forced ads.
6. Look for apps that are open source, ad free and lightweight.
7. Remove all unused quick setting "bubbles" from the quick pull down menu. I only need and have 6.

Q17. Does this rom support Magisk for root?
A17. I don't use Magisk myself so I don't know and Magisk is always being updated to fool Google's certification process. Others have reported Magisk as working, but I won't answer any questions regarding it.

Q18. Will this rom ever become official?
A18. With 19.1, legacy devices like ours will NEVER be official due to lack of ebpf support. See https://lineageos.org/Changelog-26/

Also, I don't want the responsibilities that come with being an official maintainer.

Q19. What is the difference between this rom and others?
A19. This rom tries to be pure LineageOS with little to no modifications.

Q20. Will there be any major 19.1 code modifications in the future?
A20. I don't anticipate any major modifications. There may be some small bug fixes and minor code cleanup, but all the hard work in getting the rom up and running and fixing all the major bugs have been done completed. This doesn't mean the code is perfect or well organized, but I won't be doing any major changes now that 19.1 is working.

Q21. Why did you fork the device and vendor trees for 19.1?
A21. The msm8916 repos seem geared towards phones and sometimes do not work or cause boot animation loops for tablets so I decided to fork their repos. In other words, what's deemed as msm8916-common code isn't common to all devices.

In addition, since I'm building SM-T350, SM-T357W, SM-T550, SM-P550 and SM-T560NU (all use the same msm8916 code), it seems easier to maintain all of them if I can control my own code repos and not worry if my changes affects the phones or not.

I have completely decommonized and rearranged the 19.1 msm8916-common tree so it's easier for me to maintain and build.

Q22. Can you build a variant of this device? For example, a LTE or S-pen version.
A22. If I don't physically have the device, I cannot and will not build it unless I can boot and test it myself. Even then, there's no guarantee that I can get those variant features working.

Q23. Can I load this rom on a variant devivce like LTE or S-pen version?
A23. The rom is built for the device explicitly listed. If you are an advanced user and understand TWRP, adb, odin, heimdall, you can try loading it on a LTE or S-pen variant by modifying the updater-script, but it may cause a bricked device, bootloops or non functionality of LTE/S-pen. You have been informed and warned!

Q24. What major code changes are in 19.1 vs 18.1.
A24.

- iptables has been removed in favour of ebpf
- keystore v1 has been replaced with keystore v2 which requires that the binder calls have some built-in security
- audio hal 2.0 has been deprecated
- legacy camera hal 1.0 and snap app have deprecated

Q25. I don't like the taskbar, how do I turn it off?
A25. Choose settings, type task into the search bar. Choose enable taskbar and disable taskbar. This will leave the on screen nav bar. If you want to disable that, go to settings, system, gestures, system navigation, gesture navigation.

Q26. Okay, I understand the consequences and that this is ALPHA rom and willing to take the risks outlined, now where can I find the rom?
A26. You can download it from https://sourceforge.net/projects/retiredtab/files/SM-T550/19.1/
 
Last edited:

retiredtab

Senior Member
Nov 16, 2017
1,239
815
NOTE: All builds that I upload have been personally tested on my device to boot and function as described in post #1. Having said that, there's still a chance it won't work on your device due to human error, your configuration, your apps, etc. If it won't boot, always start with a complete wipe of everything and format your data in TWRP. This is known has a clean install. Backup your data before a clean install.

19.1 has been my daily driver since March 2022.

Sept 12, 2022 release notes
1. Sept 5 security patches as per https://review.lineageos.org/q/topic:S_asb_2022-09
2. Switched to different timekeep repo that works with Android 12 and up.
3. Whatever LineageOS changed since Aug 5 patches. About 4,700 files had to be recompiled.

Aug 10, 2022 release notes
1. Aug 5 security patches as per https://review.lineageos.org/q/topic:S_asb_2022-08
2. Initial ALPHA release to public.
 
Last edited:
Wanted to report no issues with this recent version via in-place upgrade from last month's v19.1 alpha test build.

For anyone still running v17 or v18 wondering if it's worth upgrading, it depends on your use case.
Here's mine if it helps:
I use this SM-T550 tablet on a semi-regular basis for web browsing, reading e-books, and watching video content.

Using v3.6.2_90 TRWP with a microSD card and some Bluetooth headphones.
No gapps, Bromite Chromium browser, NewPipe, and all other apps downloaded via anonymous session using Aurora Store (which also works great with tracking updates).
Apps: Bitwarden (still slow, but faster than when on v18), Netguard, Netflix (no DRM issues), Nova Launcher, Plex, United Airlines app (need the Bromite browser installed for DRM content to play), and Amazon Kindle.
 
Last edited:

bierma32

Senior Member
Aug 12, 2013
1,296
524
@lower saxony
I used now more than 4 weeks and all what I have tested works perfect.
It is my daily driver.

Bluetooth works , WiFi connection is much stable if you have an worse signal.
Battery consumption I much better than Los 18.1
 

vuoshinotizy

Senior Member
May 12, 2022
122
17
I have the smt550. Do you have a guide to root it and install this rom? Where can i find it? Thanks
 

zpunout

Senior Member
Aug 26, 2015
296
60
Samsung Galaxy S5
Moto G5 Plus
can you give more info please. is good for the daily use? thanks
Everything seems to work (except RIL as mine is an LTE device). Just bear in mind that SELinux is disabled, so you might not want to use the tablet to store sensitive data.

I have the smt550. Do you have a guide to root it and install this rom? Where can i find it? Thanks
A general guide to install a custom OS for a Samsung device can be found on the LineageOS website. Here's an example for a different Samsung device https://wiki.lineageos.org/devices/beyond1lte/install

The main differences are you'll need to refer to the original post Q5 to obtain a custom recovery (TWRP) and Q26 to obtain the LineageOS build.
 

retiredtab

Senior Member
Nov 16, 2017
1,239
815
New build lineage-19.1-20220912-UNOFFICIAL-gt510wifi.zip

NOTE: All builds that I upload have been personally tested on my device to boot and function as described in post #1. Having said that, there's still a chance it won't work on your device due to human error, your configuration, your apps, etc. If it won't boot, always start with a complete wipe of everything and format your data in TWRP. This is known has a clean install. Backup your data before a clean install.

19.1 has been my daily driver since March 2022.

Sept 12, 2022 release notes
1. Sept 5 security patches as per https://review.lineageos.org/q/topic:S_asb_2022-09
2. Switched to different timekeep repo that works with Android 12 and up.
3. Whatever LineageOS changed since Aug 5 patches. About 4,700 files had to be recompiled.
 
Last edited:

Zomer123

Member
Oct 15, 2010
23
5
PLEASE BEFORE YOU decide to try this rom, you MUST read all of post 1, 2, 3 and 4 (about 10 minute read). If you think this is an unreasonable request, then stop reading now and find another rom. Thank you.

I am not responsible for lost data, identity theft, lost money, security vulnerabilities, bricked devices or any other hardware or software malfunctions that comes as a result of flashing this rom.

BACKUP YOUR DATA AND OLD rom BEFORE trying my rom.

If you are NOT an expert in using fastboot, adb, odin, heimdall, twrp, DO NOT use this rom. You must know how to use these tools to revert back to your old rom.

If you are new to flashing custom roms, do NOT attempt this.

If you need your tablet for work and something important, do NOT flash this rom. This rom could result in a bricked device or boot loop or non booting device or you not being able to revert back to your old rom.

What works

1. bluetooth
2. wifi
3. brightness
4. external audio
5. GPS
6. audio through headphone jack
7. audio over bluetooth
8. camera

What doesn't work

1. selinux is permissive. I have tried to make this build enforcing for weeks, but when I do, the OS doesn't boot and there is no adb logcat output despite making an "eng" build. Without adb logcat output, it's virtually impossible to determine what is wrong and I'm not spending anymore time on it. If having enforcing mode is important to you, use my 18.1 builds.

2. keyboard bug workaround. When prompted to enter something like a Bluetooth pin or text based password, sometimes the keyboard is not shown on the screen or off screen. The workaround is to goto settings, system, languages & input, on-screen keyboard, Android Keyboard (AOSP), appearance & layout, theme and choose "Material - follow system settings".

This keyboard bug is a LineageOS bug as per

https://review.lineageos.org/c/LineageOS/android_packages_inputmethods_LatinIME/+/325438

3. gapps. Some of you require gapps for whatever reason. I use Aurora Store for my purposes and thus have NO KNOWLEDGE of the current state of gapps.

There are various gapps projects (at least 5 in 2022). Each has pros and cons. It's your job to do the research and find a suitable gapps project. I suggest you allocate at least a couple of hours doing your own research. My rom works by itself fine without gapps. DO NOT talk about gapps in this thread. As a courtesy to gapps users, if you want to talk about gapps, I have opened a new thread at

https://forum.xda-developers.com/t/...m-t35x-sm-t550-sm-t560nu-and-sm-p550.4479285/

so you may discuss gapps wrt to the msm8916 platform. I will NOT be participating in that thread as I do NOT use gapps.

Thanks

1. LineageOS team for source code.

2. Kyle Harrison
- looking through the adb logcat and suggesting that my binder code was too old to work with Android 12's keystore2 code
- for the graphics and legacy camera patches to allow msm8916 to work with Android 12
- for his Motorola LineageOS 19.1 device trees so I could use his patches as a template for msm8916

3. @tarkzim
- adding back audio hal 2.0 and legacy camera hal 1.0 into the LineageOS trees
- helping me think through the msm8916 random reboots which was due to the TCP/IP patches
- maintaing and updating his repos so I can study them for learning purposes

4. pre ALPHA testers @breversa , @XDA_username00 for willing to test pre ALPHA builds and leaving feedback.
Hi, Installed 19.1 recovery, did factory reset, formatted system and installed 19.1 version. No error messages. Unfortunately it keeps booting into recovery only. What did I do wrong?
 

bierma32

Senior Member
Aug 12, 2013
1,296
524
@lower saxony
Hi, Installed 19.1 recovery, did factory reset, formatted system and installed 19.1 version. No error messages. Unfortunately it keeps booting into recovery only. What did I do wrong?
At first you have to tell us from which ROM or OS ( Stock ) you are comming.
Which Recovery you have installed ? TWRP or Lineage Recovery.
Have flashed only LOS 19.1 or LOS + Gapps ( which Version ) or have you flashed LOS + Gapps and Magisk ?

Try it again , factory reset and wipe cache , Data ( int. Sdcard ) System.
Flash Los and reboot system.
Is this OK . next step factory reset, flash Los and Gapps
Reboot system and so on.
 

Zomer123

Member
Oct 15, 2010
23
5
At first you have to tell us from which ROM or OS ( Stock ) you are comming.
Which Recovery you have installed ? TWRP or Lineage Recovery.
Have flashed only LOS 19.1 or LOS + Gapps ( which Version ) or have you flashed LOS + Gapps and Magisk ?

Try it again , factory reset and wipe cache , Data ( int. Sdcard ) System.
Flash Los and reboot system.
Is this OK . next step factory reset, flash Los and Gapps
Reboot system and so on.
Coming from los 18.1 (aug 2022)... Installed los 19.1 recovery. Then factory reset etc. Then installed los 19.1 (sept). No gapps, no magisk...
 
Coming from los 18.1 (aug 2022)... Installed los 19.1 recovery. Then factory reset etc. Then installed los 19.1 (sept). No gapps, no magisk...
Is there a reason for going with the LOS recovery image instead of TWRP? TWRP has worked great for me since v17 and haven't had a need for recovery with the SD Card, but then you might have a particular use case.

Remember you'll need to wipe the dalvik/data/internal storage/cache/system partitions first, then format data before installing the OS.

Hope any of that helps.
 

Zomer123

Member
Oct 15, 2010
23
5
Is there a reason for going with the LOS recovery image instead of TWRP? TWRP has worked great for me since v17 and haven't had a need for recovery with the SD Card, but then you might have a particular use case.

Remember you'll need to wipe the dalvik/data/internal storage/cache/system partitions first, then format data before installing the OS.

Hope any of that helps.
I already solved it by flashing twrp using Odin.
 

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  • 3
    New build lineage-19.1-20220912-UNOFFICIAL-gt510wifi.zip

    NOTE: All builds that I upload have been personally tested on my device to boot and function as described in post #1. Having said that, there's still a chance it won't work on your device due to human error, your configuration, your apps, etc. If it won't boot, always start with a complete wipe of everything and format your data in TWRP. This is known has a clean install. Backup your data before a clean install.

    19.1 has been my daily driver since March 2022.

    Sept 12, 2022 release notes
    1. Sept 5 security patches as per https://review.lineageos.org/q/topic:S_asb_2022-09
    2. Switched to different timekeep repo that works with Android 12 and up.
    3. Whatever LineageOS changed since Aug 5 patches. About 4,700 files had to be recompiled.
  • 7
    PLEASE BEFORE YOU decide to try this rom, you MUST read all of post 1, 2, 3 and 4 (about 10 minute read). If you think this is an unreasonable request, then stop reading now and find another rom. Thank you.

    I am not responsible for lost data, identity theft, lost money, security vulnerabilities, bricked devices or any other hardware or software malfunctions that comes as a result of flashing this rom.

    BACKUP YOUR DATA AND OLD rom BEFORE trying my rom.

    If you are NOT an expert in using fastboot, adb, odin, heimdall, twrp, DO NOT use this rom. You must know how to use these tools to revert back to your old rom.

    If you are new to flashing custom roms, do NOT attempt this.

    If you need your tablet for work and something important, do NOT flash this rom. This rom could result in a bricked device or boot loop or non booting device or you not being able to revert back to your old rom.

    What works

    1. bluetooth
    2. wifi
    3. brightness
    4. external audio
    5. GPS
    6. audio through headphone jack
    7. audio over bluetooth
    8. camera

    What doesn't work

    1. selinux is permissive. I have tried to make this build enforcing for weeks, but when I do, the OS doesn't boot and there is no adb logcat output despite making an "eng" build. Without adb logcat output, it's virtually impossible to determine what is wrong and I'm not spending anymore time on it. If having enforcing mode is important to you, use my 18.1 builds.

    2. keyboard bug workaround. When prompted to enter something like a Bluetooth pin or text based password, sometimes the keyboard is not shown on the screen or off screen. The workaround is to goto settings, system, languages & input, on-screen keyboard, Android Keyboard (AOSP), appearance & layout, theme and choose "Material - follow system settings".

    This keyboard bug is a LineageOS bug as per

    https://review.lineageos.org/c/LineageOS/android_packages_inputmethods_LatinIME/+/325438

    3. gapps. Some of you require gapps for whatever reason. I use Aurora Store for my purposes and thus have NO KNOWLEDGE of the current state of gapps.

    There are various gapps projects (at least 5 in 2022). Each has pros and cons. It's your job to do the research and find a suitable gapps project. I suggest you allocate at least a couple of hours doing your own research. My rom works by itself fine without gapps. DO NOT talk about gapps in this thread. As a courtesy to gapps users, if you want to talk about gapps, I have opened a new thread at

    https://forum.xda-developers.com/t/...m-t35x-sm-t550-sm-t560nu-and-sm-p550.4479285/

    so you may discuss gapps wrt to the msm8916 platform. I will NOT be participating in that thread as I do NOT use gapps.

    Thanks

    1. LineageOS team for source code.

    2. Kyle Harrison
    - looking through the adb logcat and suggesting that my binder code was too old to work with Android 12's keystore2 code
    - for the graphics and legacy camera patches to allow msm8916 to work with Android 12
    - for his Motorola LineageOS 19.1 device trees so I could use his patches as a template for msm8916

    3. @tarkzim
    - adding back audio hal 2.0 and legacy camera hal 1.0 into the LineageOS trees
    - helping me think through the msm8916 random reboots which was due to the TCP/IP patches
    - maintaing and updating his repos so I can study them for learning purposes

    4. pre ALPHA testers @breversa , @XDA_username00 for willing to test pre ALPHA builds and leaving feedback.
    4
    NOTE: All builds that I upload have been personally tested on my device to boot and function as described in post #1. Having said that, there's still a chance it won't work on your device due to human error, your configuration, your apps, etc. If it won't boot, always start with a complete wipe of everything and format your data in TWRP. This is known has a clean install. Backup your data before a clean install.

    19.1 has been my daily driver since March 2022.

    Sept 12, 2022 release notes
    1. Sept 5 security patches as per https://review.lineageos.org/q/topic:S_asb_2022-09
    2. Switched to different timekeep repo that works with Android 12 and up.
    3. Whatever LineageOS changed since Aug 5 patches. About 4,700 files had to be recompiled.

    Aug 10, 2022 release notes
    1. Aug 5 security patches as per https://review.lineageos.org/q/topic:S_asb_2022-08
    2. Initial ALPHA release to public.
    3
    FAQ - I spent hundreds of hours building this rom. It was frustrating process from Nov 2021 to Aug 2022 running into bug after bug. The least you can do is spend a few minutes reading everything before posting.

    Q1. Where are the source and kernel source files?
    A1. The kernel source files are at

    https://github.com/retiredtab/android_kernel_samsung_msm8916

    The device tree files are at

    https://github.com/retiredtab/android_device_samsung_msm8916-common/tree/lineage-19.1
    https://github.com/retiredtab/android_device_samsung_gt510wifi/tree/lineage-19.1
    https://github.com/retiredtab/device_samsung_gte-common/tree/lineage-19.1

    The vendor tree files are at

    https://github.com/retiredtab/android_vendor_samsung_gt510wifi/tree/lineage-19.1
    https://github.com/retiredtab/vendor_samsung_msm8916-common/tree/lineage-19.1

    The manifest.xml (or roomservice.xml) and build instructions for 19.1 are at

    https://github.com/retiredtab/LineageOS-build-manifests

    Q2. Is this ALPHA rom suitable as a daily driver?
    A2. It can be depending on your requirements. I can't test every app so you try it yourself to see if it's suitable. I've been using this rom myself since mid March 2022 with no major issues. I suggest you do a clean install, see FAQ 11, and flash this 19.1 ROM BY ITSELF (no gapps, magisk, etc) and see if you like it. If you do like it and want to add gapps then see FAQ 12.

    Q3. What if my app, xyz, doesn't work?
    A3. If your app doesn't work, then go back to your old rom.

    Q4. Your rom is laggy and buggy.
    A4. If you find the above, then go back to your old rom. There's only so much software can do on a 2015 budget level tablet. Remember a budget tablet will have the slower SoC/CPU and less DRAM than a top of the line model. Your tablet will also run slower when you use gapps. You can run a lot of software without using gapps. Research fdroid, newpipe, Aurora store etc.

    Q5. What TWRP should I use?
    A5. You MUST use TWRP 3.5.2_9. Get it from

    https://dl.twrp.me/gt510wifi/

    Q6. Why should I use this rom?
    A6. If you don't like this rom, then don't use it.

    Q7. Will you offer monthly updates with security patches?
    A7. I will try to offer monthly security patches, but that all depends on if I continue to have high speed Internet in the future.

    Q8. Can you help me? I'm a newbie. Can you provide step by step instructions?
    A8. I don't have the time to help newbies, so please do your own research. There are lots of tutorials, videos, etc on how to flash roms. Newbie questions must be posted in the Questions and Answers forum, not here.

    Q9. Can I report a bug with respect to the rom?
    A9. Yes, but you need to supply the following information. If you don't, I won't look at it.

    You must provide an adb logcat of the problem and tell me how to reproduce it. Note I will not be downloading any apps that require money or an userid/password. For example, if you have problems with Netflix, I cannot help you since I don't have a paid subscription. If you use some app that requires an userid/password, I cannot help you as I'm not willing to create another userid/password even if it's free.

    To get a logcat, open up a terminal window.
    Code:
    # clear the logcat first
    adb logcat -c
    # start logcat trace
    adb logcat > problem.txt
    # reproduce problem
    # wait until problem has occured, then stop trace by hitting ctrl-c
    # attach the problem.txt ZIPPED as text files don't seem to get attached properly

    Q10. Will you still build 18.1 for this device?
    A10. Yes, for rest of 2022, but I will make a decision in January 2023 on how 18.1 and 19.1 will be maintained. If you like to help by building 18.1/19.1, please let me know.

    Q11. Do I need to erase everything and format my data?
    A11. Yes, you MUST erase all the partitions (system, data, dalvik/art cache, cache) using TWRP and MUST format your data before installing 19.1 when you are coming from stock or an earlier version of LineageOS or from another custom rom. If you get stuck at the boot animation for more than 5 minutes, it's likely because you didn't follow the instructions I just wrote. Dirty flashes from stock, other custom roms or older LineageOS versions are not supported and not likely to work.

    Q12. What gapps should I use?
    A12. I don't use gapps anymore. I use Aurora Store. As of Nov 6, 2021, I no longer make recommendations on which gapps to use as your mileage may vary.

    Let me by crystal clear. YOU NEED TO DO YOUR OWN HOMEWORK selecting between the various gapps offered. There are 5: opengapps, nikgapps, mindthegapps, flamegapps and bitgapps. Each one will have it's own installation instructions. The only recommendation I will offer to use the SMALLEST version of gapps.

    Don't be surprised that whatever gapps you use might have problems like "Just a sec", voice not working, updating google play store please wait, etc. These are NOT problems of the OS as the OS will run fine without gapps. These are gapps problems and you must ask in the gapps forum why it doesn't work.

    In addition, some of the gapps may not install properly when using TWRP and say "cannot /mnt/system". For those cases, please use the LineageOS recovery.img you can download from

    https://sourceforge.net/projects/retiredtab/files/SM-T550/LineageOS-recovery/

    By flashing the LineageOS recovery.img, it will overwrite the existing TWRP and you will get a different UI.

    Q13. I'm having problems with gapps, can you answer why it's not working?
    A13. I WILL NOT answer any questions regarding gapps. This thread is about the rom, not gapps. Android does not depend on gapps in order to work.

    Questions about gapps, for your courtesy, should be asked at

    https://forum.xda-developers.com/t/...m-t35x-sm-t550-sm-t560nu-and-sm-p550.4479285/

    Q14. Why isn't my post answered or ignored?
    A14. Questions already answered in the FAQ will be completely ignored. Again, I do not use Windows OS or gapps.

    Q16. What speed up/optimization tips do you suggest?
    A16.

    1. Turn off animations. Go into developer settings, scroll down to the drawing section, and set window, transition and animator scale all to "off".
    2. If you don't have a google account, don't install gapps. Use Aurora Store to get your apps as you can get all the same apps from the play store using an anonymous login.
    3. Dont' run more than 2 apps at the same time. You can probably listen to music in the background and use a web browser at the same time, but don't expect great performance from a 2015 entry level tablet.
    4. Use a web browser like Brave that has built in adblock and privacy features.
    5. Use newpipe to watch your streaming content. It has built in adblock so you don't have to watch forced ads.
    6. Look for apps that are open source, ad free and lightweight.
    7. Remove all unused quick setting "bubbles" from the quick pull down menu. I only need and have 6.

    Q17. Does this rom support Magisk for root?
    A17. I don't use Magisk myself so I don't know and Magisk is always being updated to fool Google's certification process. Others have reported Magisk as working, but I won't answer any questions regarding it.

    Q18. Will this rom ever become official?
    A18. With 19.1, legacy devices like ours will NEVER be official due to lack of ebpf support. See https://lineageos.org/Changelog-26/

    Also, I don't want the responsibilities that come with being an official maintainer.

    Q19. What is the difference between this rom and others?
    A19. This rom tries to be pure LineageOS with little to no modifications.

    Q20. Will there be any major 19.1 code modifications in the future?
    A20. I don't anticipate any major modifications. There may be some small bug fixes and minor code cleanup, but all the hard work in getting the rom up and running and fixing all the major bugs have been done completed. This doesn't mean the code is perfect or well organized, but I won't be doing any major changes now that 19.1 is working.

    Q21. Why did you fork the device and vendor trees for 19.1?
    A21. The msm8916 repos seem geared towards phones and sometimes do not work or cause boot animation loops for tablets so I decided to fork their repos. In other words, what's deemed as msm8916-common code isn't common to all devices.

    In addition, since I'm building SM-T350, SM-T357W, SM-T550, SM-P550 and SM-T560NU (all use the same msm8916 code), it seems easier to maintain all of them if I can control my own code repos and not worry if my changes affects the phones or not.

    I have completely decommonized and rearranged the 19.1 msm8916-common tree so it's easier for me to maintain and build.

    Q22. Can you build a variant of this device? For example, a LTE or S-pen version.
    A22. If I don't physically have the device, I cannot and will not build it unless I can boot and test it myself. Even then, there's no guarantee that I can get those variant features working.

    Q23. Can I load this rom on a variant devivce like LTE or S-pen version?
    A23. The rom is built for the device explicitly listed. If you are an advanced user and understand TWRP, adb, odin, heimdall, you can try loading it on a LTE or S-pen variant by modifying the updater-script, but it may cause a bricked device, bootloops or non functionality of LTE/S-pen. You have been informed and warned!

    Q24. What major code changes are in 19.1 vs 18.1.
    A24.

    - iptables has been removed in favour of ebpf
    - keystore v1 has been replaced with keystore v2 which requires that the binder calls have some built-in security
    - audio hal 2.0 has been deprecated
    - legacy camera hal 1.0 and snap app have deprecated

    Q25. I don't like the taskbar, how do I turn it off?
    A25. Choose settings, type task into the search bar. Choose enable taskbar and disable taskbar. This will leave the on screen nav bar. If you want to disable that, go to settings, system, gestures, system navigation, gesture navigation.

    Q26. Okay, I understand the consequences and that this is ALPHA rom and willing to take the risks outlined, now where can I find the rom?
    A26. You can download it from https://sourceforge.net/projects/retiredtab/files/SM-T550/19.1/
    3
    New build lineage-19.1-20220912-UNOFFICIAL-gt510wifi.zip

    NOTE: All builds that I upload have been personally tested on my device to boot and function as described in post #1. Having said that, there's still a chance it won't work on your device due to human error, your configuration, your apps, etc. If it won't boot, always start with a complete wipe of everything and format your data in TWRP. This is known has a clean install. Backup your data before a clean install.

    19.1 has been my daily driver since March 2022.

    Sept 12, 2022 release notes
    1. Sept 5 security patches as per https://review.lineageos.org/q/topic:S_asb_2022-09
    2. Switched to different timekeep repo that works with Android 12 and up.
    3. Whatever LineageOS changed since Aug 5 patches. About 4,700 files had to be recompiled.