yashsingh1/xdaforums huggingface dataset:
[Samsung Galaxy Tab A series Guides, News, & Discus] Talich52:
I won't tell you here, since I'm not a programmer, but just a user with a lot of experience... Look in the market, there may be a program for the necessary actions.

P.S. Perhaps this information will help: The device is easily routed with the Android bootloader 9 even on the latest firmware and works without problems. But there is one point - you can not charge the device when it is turned off, when the charger is connected, the device freezes on the screen, which is shown above. The loader is to blame for this, but I have not tried whether it is possible to install the loader 11 android, since my model is T295 and the loader is already 4 versions, which can no longer be replaced with version 3. The model also has a T290 loader on Android 11 version 3 and maybe a replacement will turn out...

Good luck!
[Samsung Galaxy Tab A series Guides, News, & Discus] J.Michael:
I don't know what the playlpm file is.

You should not modify the system partition. Sometimes it works, sometimes not. Magisk makes it possible to virtually "replace" a file -- you should look into the (very little) required.

So we're back to playlpm: Was there one before you changed it? What did it say? Why did you modify it?
[Samsung Galaxy Tab A series Guides, News, & Discus] bingo1951:
T295XXU4CVG3 ????????????????????????????
[Samsung Galaxy Tab A series Guides, News, & Discus] Talich52:
There is a version 4 bootloader in the firmware, which cannot be replaced with a version 3 bootloader from Android 9 - there is a ban on lowering the bootloader version from Google and Samsung. Bootloaders 10 and 11 of Android have enhanced protection and even with an unlocked bootloader, you cannot install a custom (patched) kernel or recovery (TWRP), that is, get Root rights :(
[Samsung Galaxy Tab A series Guides, News, & Discus] bingo1951:
grazie
[Samsung Galaxy Tab A series Guides, News, & Discus] vidtek:
There are 2 files in the /system/bin directory that affect the charging regimes of all tablets/phones. /system/bin/lpm is the one in the firmware I have in my system. It was a binary file and I had a look in a hex editor and it was quite a complex affair, detailing how long the charging should take and what happens when the charger is plugged in. /system/bin/playplm is a similar file, but very much smaller with less options. These are the files to modify to make the tablet/phone boot on charger connection. My system just had the single file /system/bin/lpm file so I renamed that to /system.bin/lpm.bak and copied my modified version of /system/bin/playlpm. I did modify the playlpm file to read this:

#!/system/bin/sh
su
/system/bin/reboot

The original /system/bin/lpm file has over 2000 lines of code.

Tony
[Samsung Galaxy Tab A series Guides, News, & Discus] Talich52:
I believe that the changes do not work, since the current bootloader is from android 9, with which the device does not charge in the off state. Try to replace the bootloader with a regular android 11, I attach the file.This is a BL file and first unpack it from the zip archive to .tar.md5, select BL or AP in the window and flash it. If there is a problem with startup or Root rights, then flash back the file aboot_vk_T290XXS3ATF1.tar, which I posted above, and I will attach it again.

Good luck!

PS in another related topic, they assured me that the T290 can be rooted with the Android bootloader 11, but I can't check it because I have 2 devices, but the T295 models. Try it and if anything, return (flash back) the bootloader 9 android...
[Samsung Galaxy Tab A series Guides, News, & Discus] vidtek:
Talich - I tried the file but resulted in the blue screen with red writing as posted in post #456 in this thread. I re-flashed all 4 files of the original

T290XXS3ATF1 that was originally on this tablet. Back to square one after another 3 days out of my useless life.....
[Samsung Galaxy Tab A series Guides, News, & Discus] Talich52:
I suppose it was enough to flash the android 9 bootloader back, that is, the aboot_vk_T290XXS3ATF1 file, and not go full circle. Unfortunately, such a dilemma is either Root-rights with the Android 9 bootloader, but then the charging of the switched off device does not work. But frankly, I don’t understand why they turn off the device, even if it eats up 2-3% of the total charge overnight?

But in general, every evening I put the device on charge without turning it off ... The battery is in excellent condition :)

P.S. I made a mistake by recommending to flash the full file of BL bootloaders for android 11! there was no need to return the vk file (vaultkeeper.img), and we also returned the original vbmeta file, and did not leave the patched Magisk. If you have the strength and desire, then repeat everything, but only flash the aboot.mbn file for Android 11, which I will attach for installation via ODIN.
[Samsung Galaxy Tab A series Guides, News, & Discus] vidtek:
In the end, I have flashed it all back to as it was when I bought it and then took every modified file I could find and flashed that into the BL and AP slots.

The result is a rooted tablet with magisk and twrp installed and it now boots when the power is applied.

I have no idea which file did it, I must have flashed about half a dozen, but I got the result I have been looking for - yay!

I should have taken more care and documented each stage which is what I normally do, but I was past caring and just went for it.......

Thank you to all on this thread, particularly Michael and Talich.
[Samsung Galaxy Tab A series Guides, News, & Discus] J.Michael:
It's a pretty safe bet that only the last file flashed to each partition matters. But if you took a flock of tar files and ran Odin using two tar files at a time, it's hard to predict what came from where -- AP and BL are not partitions, they are just the way Samsung organizes their firmware delivery. Each tar file contains one or more files, each of those files is a partition image.

Can you identify the half-dozen files you flashed, and check their contents to see if any partition names are duplicated? And maybe check to see if the duplicated names' files happened to be identical?
[Samsung Galaxy Tab A series Guides, News, & Discus] vidtek:
Michael - I had wondered about the names Odin uses to separate files as it seems BL and AP are interchangeable in some cases, that led me to suspect what you have said about being unrelated to actual partitions. It will take me a while to go through the files unpack them and get the information you require. It will obviously help everyone to know what is what, please be patient it will take me some time to gather the information-I should have done my usual documentation...doh!
[Samsung Galaxy Tab A series Guides, News, & Discus] Talich52:
Congratulations on solving the issue :) If it is not difficult, then install the attached program and make a screenshot of the Firmware Information tab. It may have been possible to root the device with the android bootloader 11 and therefore the charging works in the off state. By the name of the loader, it will be clear that it is from android 9 or 11... Thanks!
[Samsung Galaxy Tab A series Guides, News, & Discus] vidtek:
Looks like I spoke too soon, this morning when I switched on the ignition (or whatever you call an EV power up state) and power was applied to the tablet I got the ususal hang with the Samsung logo. Previously it must have been actually switched on so fooled me into thinking it was powering up properly...sigh....silly old fart should have known it wouldn't be that easy.
[Samsung Galaxy Tab A series Guides, News, & Discus] vidtek:
Talich - here are the screenshots from your programme.

Given root rights and inserting my /system/bin/playlpm file; the system still hangs on boot whenpower is applied. I ensured the file has the correct attributes w+r+x

Tried deleting the /system/bin/lpm file but it refuses to budge. Perhaps if I could get rid of that I may be able to sort the boot hang.

Now stuck ...... again!

Tony
[Samsung Galaxy Tab A series Guides, News, & Discus] J.Michael:
What is this "playlpm" file? Why are you messing with it? How did you mess with it?

Have you searched the site? Google led me to this thread where @callumw was ultimately successful.
[Samsung Galaxy Tab A series Guides, News, & Discus] vidtek:
Michael, thank you for helping. The playplm file is exactly as Callum posted, I have tried both versions, as I posted in #487 this thread. It would seem to me that Samsung have messed around with this new /system/bin/lpm file (which doesn't seem to appear in older devices), extending the functionality to cover all sorts of eventualities with charging instead of the playlpm file which is not there at all. I have searched every site under google and duckduck with no joy.

My issue now is I seem unable to move/delete/rename the /system/bin/lpm file. It just stubbornly refuses to be tampered with, even though I have read/write and root rights for this folder. Just weird, I use Linux; I am comfortable with the cli and simple programming, rarely resort to Windows although there is no decent equivalent for Odin so use a VM to flash files in Odin with win 8.1. I have tried ES and Total Commander maybe there is another root file manager you could recommend for Android?

Cheers Tony
[Samsung Galaxy Tab A series Guides, News, & Discus] J.Michael:
You are generally advised not to try to change /system. Magisk has a facility that enables "overlaying" or "masking" files, but it only works when Magisk is active. I think I've also seen cautions about when in the boot process a file will be used -- Magisk can't "mask" until past a certain point.

The talk about using a shell script makes it seem there is an Android running when you think your device is shut down. And it uses at least some files in /system. So the question becomes "what boot image is it using?"

Have you tried making a Magisk module to replace this file?

Did you try the instructions involving remounting /system? (After reading Wu's warning that just remounting could trip the tamper protections?)
[Samsung Galaxy Tab A series Guides, News, & Discus] vidtek:
I haven't tried making a Magisk module, no. Wu's warning? Can you tell me where to find it please?
[Samsung Galaxy Tab A series Guides, News, & Discus] Talich52:
I see on the screenshot the loader T290XXS3ATF1 from android 9, with which charging does not work when turned off. I need an android loader 11, the file of which I posted above is aboot_T290XXU3CVG3.tar. Try to flash it and if the device continues to work, the charging of the switched-off device will also work. If there is a problem, just flash back the loader T290XXS3ATF1, this is the aboot_vk_T290XXS3ATF1.tar file laid out above. For firmware, select files in the BL or AP ODIN window. The problem, I believe, is precisely the inability to fully charge Android 11 with a 9 loader
[Samsung Galaxy Tab A series Guides, News, & Discus] vidtek:
I have tried multilple times to flash the aboot_T290XXU3CVG3.tar file, it always results in the blue screen with the red warning at the top as in post #456 in this thread. Maybe when I have tried to flash it I haven't been fast enough mashing the buttons to try and get to recovery after the flash-what do you think-should I try again?
[Samsung Galaxy Tab A series Guides, News, & Discus] Talich52:
Read the topic from here:

https://xdaforums.com/t/rom-twrp-sm-t290-sm-t295-discussions-help-thread.4031223/post-87207591

If youIt is claimed that it is possible to install TWRP and root the device with the original android 11 bootloader, but the firmware is specified at most VE1, I can't check, since I have a T295 model... manage to root the device with the android bootloader 11, then I'm sure the necessary option will work :)

P.S. And another crazy option is to roll back the firmware to 9 android T290XXS3ATF1, root and use in full ... ;)
[Samsung Galaxy Tab A series Guides, News, & Discus] J.Michael:
There isn't much to making a module that just masks some files. I think in your case you would create a file /data/adb/modules/lpm-module/system/bin/lpm

Probably make sure file has owner and permissions of original (file being "replaced").

After rebooting, it should be clear whether the file got replaced. Then you can try the charger scenario of interest to see if it has any effect.

I thought the warning was in the Magisk install instructions. Maybe it's in some other document in his github.

If you have remounted /system and you can still boot, then clearly it is not as dangerous as I thought.
[Samsung Galaxy Tab A series Guides, News, & Discus] vidtek:
Still struggling, I had a go at modifying my /system/bin folder replacing the lpm file with my own following these ideas: Lolvatveo's tutorial.

Everything went surprisingly smoothly until I came to the block count. I ended up with a system.img file of just 63Mb, instead of about 3gb. I have been unable to work out why the

tune2fs -l system.img | grep "Block size\|Block count"

gave me such a small block count.

I flashed it anyway and the tablet gave an error with "no operating system installed" (Paraphrasing).

Back to square one.
[Samsung Galaxy Tab A series Guides, News, & Discus] J.Michael:
What did "tune2fs" say about the original "system.img" you extracted from the AP.tar file?

Did you make any sense of the post following the post you cite, in which @xs23933 claimed he got something he didn't like, and then cited one "tune2fs" output, apparently believing that made it obvious about what he was talking.
[Samsung Galaxy Tab A series Guides, News, & Discus] vidtek:
Michael - yes I did look at that post carefully, but I couldn't see quite what he was getting at, except his failed in the same manner as mine. No obvious solution there. I will see what tunefs has to say about the original though-that's a good place to start. I'll report back.
[Samsung Galaxy Tab A series Guides, News, & Discus] vidtek:
OK reporting back. I selected 2 different iterations of the available systems from Samsung for my Tab A, the original T290XXS3ATF1 and also the T290XXU3CVG3 versions.

I went through the procedure of untar and unlz4 to isolate the system.img and mounted the system.img in a loop file as in these instructions:

https://stackoverflow.com/questions...ack-and-flash-system-img-ext4-file-using-odin

I removed the /system/bin/lpm file and replaced it with my own, adhering to the correct permissions as per the original lpm file.

I then found some strange anomalies with the procedures. Because the system.img was mounted as a loop device, there was not enough room for the packing command to work.

I cheated by copying the whole mounted system.img to a different folder on my drive and was able to produce a 3.8gb file (for both the ATF1 and the CVG3 versions).

I also had to ensure the make_ext4fs binary was in the /(myfolder)/system

folder for it to work.

Then came the flashing to the tablet.

Results for ATF1: Boot loop

Results for CVG3: Boot loop.

At this point I am giving up, Samsung have just stuffed it all up too much, I have spent way too much time on getting nowhere and there are more productive things for me to do.

I will use the tablet as per factory, just having to switch it on, another routine when starting the car I will have to get used to it and it will become automatic.

I will use Tasker to run a routine to switch it off when turning off the ignition, that is easy.

The best of luck to all that follows me down this rabbit hole, I hope you have better fortune than I.

Cheers Tony.
[Samsung Galaxy Tab A series Guides, News, & Discus] Talich52:
You didn't write anything about the core, I guess it's stock? But the protection of the stock kernel will not allow loading the custom system. To disable protection, you need to patch the Magisk kernel. More precisely, the boot.img file and the vbmeta.img file. You can flash it along with the system by selecting ODIN UserData in the window.

In general, I previously recommended simply installing 9 android T290XXS3ATF1, rutting and making the necessary changes - I think this is a working option :) Unfortunately, I can’t check it myself ...

Good luck!
[Samsung Galaxy Tab A series Guides, News, & Discus] vidtek:
Talich - thanks for your input again. It was a stock core downloaded from Samsung, I thought I'd made that clear, sorry.

It wasn't a custom system, it was identical except for that single LPM file.

My file is 38bytes, the original was 345 or thereabouts (from memory), maybe the file size was detected?

I didn't want to keep the Android 9 with the associated issues with charging-that's exactly what I am trying to alter.

Tony
[Samsung Galaxy Tab A series Guides, News, & Discus] J.Michael:
Have you ever succeeded in installing Magisk?

Have you tried "overlaying" the lpm file using a Magisk module?

I am ready for the answer to be that it doesn't help because Magisk is not running when this file is executed, but this is such a simple experiment, I think you should at least try.

What is the original "lpm" doing? Is it a shell script?

My "lpm" is 335KB. Did you forget to say "K", or is yours really so much smaller?

Shouldn't your "patch" be trying to run the original lpm, and *then* reboot?
[Samsung Galaxy Tab A series Guides, News, & Discus] J.Michael:
@vidtek Have you seen this thread about doing what you describe, but on an S7?
[Samsung Galaxy Tab A series Guides, News, & Discus] vidtek:
Michael- Thank you too for your help. I have managed to install Magisk - about 5 times!

No I'm not sure what you mean by "overlaying" a Magisk module.

Yes the original LPM file is a shell script. It controls the charging port and it's various states.

Yes of course it should have been KB ... don't get old......

My "patch" just replaced the LPM completely, maybe that's where I went wrong.

In your other post you gave a link where someone just added the lines in my file to the end of the LPM file on an S7 and it worked. Maybe that's all I had to do!!

Cheers Tony.
[Samsung Galaxy Tab A series Guides, News, & Discus] Talich52:
Very likely. However, you can't hear me, and I will say again that everything would have worked out if both the system and the loader were the same version, 9 or 11. If the system is android 11, and the bootloader is android 9, then charging the switched-off device does not work properly. Hence I think the problem... Unfortunately, although they claim that they rooted the T290 on Android 11 with a regular loader, but you failed, and I did not check on the T295 model... Therefore, there was a recommendation to do everything on Android 9, on the T290XXS3ATF1 firmware
[Samsung Galaxy Tab A series Guides, News, & Discus] vidtek:
Talich - From memory I think the original system when I purchased it was Android 10, not 9. This is my present system:
[Samsung Galaxy Tab A series Guides, News, & Discus] Talich52:
You can roll back to android 9, but with version 3 of the loader, say T290XXS3ATF1 . Alternatively, on the current full firmware of android 11, just look at how charging works when the device is turned off.Then flash the bootloader from android 9 aboot_vbmeta_T290XXS3ATF1.tar and compare the picture when charging. You don't need to root, just see the root of the problem...

I never turn off the device, so I don't see a problem when charging...
[Samsung Galaxy Tab A series Guides, News, & Discus] vidtek:
That's where I started ha!

The boot behaviour with Android 11 and the Android 9 bootloader displays the same as you describe, it will only charge when up and running.
[Samsung Galaxy Tab A series Guides, News, & Discus] J.Michael:
"overlaying": A Magisk module is a directory tree in /data/adb/modules. One of the effects of a Magisk module is that a file under /data/adb/modules/${module-name}/system will be "mounted" by Magisk in such a way that everyone other than Magisk will see the file provided by the module, instead of seeing the file at the corresponding position under /system. So, I was suggesting that you put your version of lpm at /data/adb/modules/fixlpm/system/bin/lpm to see if that changed your charging behavior.

WARNING: a bad module can make it impossible to boot. There are things you can do to deactivate a module. You should read about them.

I doubt that the original lpm is a shell script. On my system it is identified as an ELF file, a kind of binary executable.

The thread I referenced did *not* talk about appending to lpm, it talked about overwriting lpm. Those people apparently can get away with remounting /system read/write. Someone suggested that it was important for the lpm file to be at a particular inode. Overwriting the original lpm was a way to achieve that. I don't remember whether he claimed that was verified. It may just be that that avoided perturbing the layout of the disk image -- we have reason to believe that Samsung detects "changes" to /system, but we don't know that they scan the whole thing every time you boot. They may have taken a shortcut, and overwriting lpm might evade detection.
[Samsung Galaxy Tab A series Guides, News, & Discus] vidtek:
Michael - Thank you for explaining the Magisk overlay. Interesting, I'll read up on modules as you suggest. It's good to keep the old brain cells ticking over and active when you are over 70... It's a very long time since I wrote my first database using database3 in 1986 for my fledgling business-I couldn't justify an off the shelf solution when starting out and it taught me a lot.
[Samsung Galaxy Tab A series Guides, News, & Discus] Minionguyjpro:
Nice, i also made a guide for the SM-T290 model which i have myself and also rooted. When you figure out how it works, you can do it more flawless.
[Samsung Galaxy Tab A series Guides, News, & Discus] Skycreedph:
bro error 04 google drive
[Samsung Galaxy Tab A series Guides, News, & Discus] ebod:
Hi All, I have just bought a used SM-T295 which I want to use in an old car to hook up to its existing audio system , so that it can auto startup/shutdown etc.

Presently its stock android 10 and I would prefer to root it from the outset.

I here as a newbie and always fall at the first hurdle, more often because I see instructions on XDA only to learn that parameters/events have changed since a guideline was first written. For example on this tab, I've done the multiple tapping to get dev options, and already stuck as there seems to be no OEM unlock option.

So I would greatly appreciate advice on whether ...as of Feb24 are the instructions at the top of this thread still 100% valid to achieve root.

Secondly, if this tab is stock Android 10, ( rom T295XXU3BTI4 ) is there a standard go-to rom upgrade to make it 'better'. Nothing that makes it flakey...only want 100% stable rom upgrades.

Many thanks
[Samsung Galaxy Tab A series Guides, News, & Discus] Minionguyjpro:
Hi there,

I think you must wait for 7 days, because the device just got installed, and after that you will find the option in developer options. If you don't want to wait, you could try to set the date to earlier or further.
[Samsung Galaxy Tab A series Guides, News, & Discus] Talich52:
Do not update the firmware to version 4 and 5 of the bootloader, otherwise you will not be able to root the device ...
[Samsung Galaxy Tab A series Guides, News, & Discus] ebod:
Thanks, I've tried the reverse date but unfortunately it wont work, I followed this guide but unsuceesfully https://itoolab.com/unlock-android/enable-oem-unlock-missing/
[Samsung Galaxy Tab A series Guides, News, & Discus] ebod:
Right now I wish I even knew what was installed on the device. It was bought used off ebay but I've got no reason to believe its ever been modded before. How can I check what version I have? Would this mean doing one of them startups holding the vol+ & power button?
[Samsung Galaxy Tab A series Guides, News, & Discus] J.Michael:
Look at Android Settings -> About -> Software
[Samsung Galaxy Tab A series Guides, News, & Discus] Talich52:
The current version of the bootloader is 3. The letter B means 10 android, C - 11 android.
[Samsung Galaxy Tab A series Guides, News, & Discus] ebod:
OK thanks for clarifying. So it looks like I can commence root once I manage to get past the initial OEM unlocking hurdle, which could be another week lol. I just hope the instructions in the top post are still valid for use.