There's a new version of twrp in the OP. Two main changes:
1. removed an unnecessary HAL service - thanks to @HemanthJabalpuri
for pointing this out
2. removed the bluetooth
partitions from twrp UI
why were the partitions removed from twrp?
discovered that bluetooth
partitions were not restoring in twrp. It turns out they were not being backed up properly either.
The problem was related to how those two partitions are mounted. They are mounted as vfat
format. There are known problems with the libraries that twrp uses to backup/restore vfat partitions. Twrp was unable to restore the modem
partition - probably because the backup was corrupt.
I could workaround this problem by mounting the partitions in emmc
format and taking a bitwise backup/restore. The backup/restore worked, but you couldn't mount the partitions in twrp. So then I thought - why bother? Both partitions can be restored by flashing them with the stock ROM anyway. Unless you are modifying those partitions, you don't need a twrp backup.
If you need to restore the bluetooth
partition, flash the BTFM.bin
from your stock ROM. If you need to restore the modem
partition, flash the NON-HLOS.bin
from your stock ROM. Remember to use the same stock ROM as your tablet.
The android bootloader partition (abl) was also removed from twrp. It can be restored by flashing abl.elf
from your stock ROM.
If you really want to play with these partitions in twrp, you can still mount them manually from the terminal or in ADB etc.