TWRP for Samsung Galaxy A21s aka a21s

Credits: corsicanu for original c2s source

Bugs

Everything works except for the following:

• Decryption*

Decryption does not work on this device and if your device is encrypted then TWRP will be unable to view your files. To Decrypt your device, enter the terminal in TWRP and run the multidisabler command

Features

• DTB: Imported KawaKernel A12 DTB
• DTBO: Imported KawaKernel A12 DTBO
• Implemented multidisabler command
• Implemented sgdisk command
• Recovery Kernel: KawaKernel-R

Building

Make tw directory and go into it

mkdir tw; cd tw

Clone A21s device tree to device/samsung/a21s

git clone https://github.com/DozNaka/android_device_samsung_a21s device/samsung/a21s

Init TWRP AOSP 12.1 manifest repo

repo init --depth=1 -u https://github.com/minimal-manifest-twrp/platform_manifest_twrp_aosp.git -b twrp-12.1

Sync repo and wait

repo sync

Begin building TWRP

export ALLOW_MISSING_DEPENDENCIES=true; . build/envsetup.sh; lunch twrp_a21s-eng; mka recoveryimage

Output will be in tw/out/target/product/a21s/recovery.img

Installation

DISCLAIMER: If this is your first time modding A21s then YOU NEED TO REFLASH STOCK ROM FIRST!

If you do not do this then you will get KG STATE blocked and you will have to flash stock firmware anyway to fix it. So sorry linux users but you will need to use Odin (Not JOdin or heimdall) to reflash stock rom

Requirements: Rooted by flashing AP file via Odin that was patched using Magisk App OR patched vbmeta

To root your device with the patch AP method you do the following:

• Install Bifrost apk
• Download stock firmware using the Bifrost app
• Extract AP from firmware
• Install Magisk
• Open Magisk, press Install and then Select and Patch a File
• Select the AP file you have extracted from stock firmware
• Once finished patching, you will find the patched AP file in Downloads
• Move the patched AP file to your computer
• Flash the patched AP file with Odin

If you are on linux then extract the AP file and flash vbmeta and boot images with heimdall

Once you have finished this you can proceed with the methods below:

Method 1: recovery.img

• If you are on linux then flash recovery.img with heimdall

heimdall flash --RECOVERY recovery.img

OR

• You can the TWRP app to flash the recovery.img

OR

• You can use the dd command to flash recovery.img by placing the recovery.img in /sdcard and running these commands

su

dd if=/sdcard/recovery.img of=/dev/block/by-name/recovery

Method 2: recovery.tar

• Place the tar file in AP in Odin then flash

Booting to TWRP

• Once TWRP is flashed, boot to it with volume up + power combo
• Go to Advanced -> Terminal, then you will enter the multidisabler command
• Reboot to recovery again
• Format data as you will get bootloops if you don't