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Samsung Galaxy A31 (samsung-a31)

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Samsung Galaxy A31
Device running pmOS Edge with Xfce4
Device running pmOS Edge with Xfce4
Manufacturer Samsung
Name Galaxy A31
Codename samsung-a31
Released 2020
Type handset
Hardware
Chipset MediaTek Helio P65 (MT6768)
CPU 2x 2.0 GHz Cortex-A75
6x 1.8 GHz Cortex-A55
GPU Mali-G52 MC2, 2 core 1000 MHz
Display 1080 x 2400; 60GHz
6.4" 20:9 ratio
Super AMOLED
Storage 64/128 GB
Memory 4/6/8 GB
Architecture aarch64
Software
Original software
The software and version the device was shipped with.
Android 10 (OneUI 2.1)
Extended version
The most recent supported version from the manufacturer.
Android 12 (OneUI 4.1)
postmarketOS
Category downstream
Mainline
Instead of a Linux kernel fork, it is possible to run (Close to) Mainline.
no
pmOS kernel
The kernel version that runs on the device's port.
4.14.195
Features
Flashing
It is possible to flash the device with pmbootstrap flasher.
Untested
USB Networking
After connecting the device with USB to your PC, you can connect to it via telnet (initramfs) or SSH (booted system).
Works
Internal storage
eMMC, SD cards, UFS, ...
Works
SD card
Also includes other external storage cards
Works
Battery
Charging and battery level reporting works
Works
Screen
Display works. Ideally with sleep mode and brightness control.
Partial
Touchscreen
Works
Multimedia
3D Acceleration
Broken
Audio
Audio playback, microphone, headset and buttons.
Broken
Camera
Untested
Camera Flash
Partial
Connectivity
WiFi
Broken
Bluetooth
Broken
GPS
Broken
NFC
Near Field Communication
Untested
Modem
Calls
Broken
SMS
Broken
Mobile data
Broken
Miscellaneous
USB OTG
USB On-The-Go or USB-C Role switching
Works

Contributors

Users owning this device


Bootloader (ODIN)

Entering

Power off the device.
Press & hold Volume Up+Volume Down while plugging USB cabel into computer.
Then press Volume Up to confirm.

Unlocking

Warning WARNING: This will erase all user data!
Flashing custom partitions will blow the Knox eFuse and will warranty void.

Be sure you are registered the device in Software Updates menu. (just check for them)

  1. Enter to Developer Menu and activate OEM Unlock.
  2. Power off the device and enter bootloader.
  3. Press & hold Volume Up and wait few seconds. After that confirm unlocking by pressing Volume Up.

EFS & NVRAM

Remember that backing up the partitions containing IMEI and SN is really important. Otherwise, it may lead to consequences in the form of cellular service failure or mistrust from services.
So far, the possibility to restore IMEI has not been found.
Possible options to make a backup copy are

  • from recovery mode
  • directly dd if=/dev/block of=*.img

Partitions related to this list

  • efs (mmcblk0p3)
  • sec_efs (mmcblk0p4)
  • nvcfg (mmcblk0p10)
  • nvdata (mmcblk0p11)
  • nvram (mmcblk0p29)
  • persistent (mmcblk0p17)

Boot ROM

Boot ROM is a protected section of processor memory that controls system startup and provides an emergency mode to recover the device in case of firmware corruption.
It can be accessed via Test Point on the motherboard or already if you broke the bootloader and "the device doesn't show any signs of life"

There may be a manual, I can't promise.
In the links will be attached scatter firmware for S4 bootloader for SP Flash Tool.

Other