[Thinkpad Tablet Android Development] yener90:
/*
* I'm not responsible for bricked devices, dead SD cards, thermonuclear war, or you getting fired because the alarm app failed (like it did for me...).
* Please do some research if you have any concerns about features included in the products you find here before flashing it!
* YOU are choosing to make these modifications, and if you point the finger at me for messing up your device, I will laugh at you.
* Your warranty will be void if you tamper with any part of your device / software.
* Same statement for XDA.
*/

LineageOS is a free, community built, aftermarket firmware distribution of Android 9 (Pie), which is designed to increase performance and reliability over stock Android for your device.

LineageOS is based on the Android Open Source Project with extra contributions from many people within the Android community. It can be used without any need to have any Google application installed. Linked below is a package that has come from another Android project that restore the Google parts. LineageOS does still include various hardware-specific code, which is also slowly being open-sourced anyway.

All the source code for LineageOS is available in the LineageOS Github repo. And if you would like to contribute to LineageOS, please visit out Gerrit Code Review.

What works:

Wifi

Bluetooth

Audio

LED

USB

RIL

Encryption

Fingerprint

Camera

Hall sensor

DT2W

Selinux Enforcing

Broken

nothing

Source code:

device: https://github.com/lenovo-devs/android_device_lenovo_TBX704

device-common: https://github.com/lenovo-devs/android_device_lenovo_tb-common

kernel: https://github.com/lenovo-devs/android_kernel_lenovo_msm8953

vendor: https://github.com/lenovo-devs/proprietary_vendor_lenovo

Important

If you are using this ROM first time, wipe data. Wipe data completely. I mean the option where you need to enter "yes". Use this option and then flash the rom.

This ROM only works with the TWRP I added.

If you want to use GAPPS, flash it directly after flashing ROM. Don't let the ROM boot. Otherwise your device will not get certification, so you will not have Google Access.

Instructions

(thx [MENTION=6347536]matshias[/MENTION], just changed few lines to get ROM flashing working)

Put your ROM (and GApps) onto your sdcard (sdcard must be exfat or fat32, NTFS not supported)

Install fastboot and adb on your PC, e.g. from here

Enable developer options and in there select to unlock your bootloader by enabling OEM unlock and enable USB debugging

Connect your PC to your tablet and run

adb reboot bootloader

using adb on command line. The tablet will reboot into bootloader mode where you will only see the Lenovo logo. Now you use

fastboot oem unlock-go

to unlock. This will factory reset your device

Don't setup, cause you will need to format your tablet later again. Shutdown tablet. Hold volume up and power button to start to bootloader

Then run

fastboot flash recovery twrp-3.2.3-0-<your-filename>.img

to flash TWRP

Select with volume buttons "Recovery Mode" and press power button

Select to write to system, otherwise you can't flash ROM

Backup at least system and boot partitions to your sdcard cause you will wipe data in next step. Choose "System Image" for the system partition backup.

Format data using this tutorial

Flash ROM

Optionally flash SuperSU or Magisk in TWRP which should install system less. Keep OEM unlock enabled if you flash or modify anything

Restart

Download

2019-08-12 (hotfix)

• hotfix: fix camera

• security patch level: 2019-08-01

ROM

TWRP (Use this for TB704L too; you guys don't need 4g in recovery :p)

You can also get the latest ROM updates from codeworkx here:

https://sourceforge.net/projects/lineageos-on-lenovo/files/16.0/TBX704/

Bulids are same, just update.

Older downloads

2019-07-14

• security patch level: 2019-07-05

ROM

TWRP

2019-06-22 (thx [MENTION=3208754]codeworkx[/MENTION])

• bugfixes and performance improvements

• fix camera detection for ov8856 sensor

ROM

2019-06-09 (thx [MENTION=3208754]codeworkx[/MENTION])

• bugfixes and performance improvements

• set_permissive.zip patch no more required

• TWRP 3.3.0 support

• security patch level: 2019-06-05

ROM

2019-05-14

• fixed sim issue for x704l caused in last update

• fixed a little issue on x704l (should improve battery life)

• added double tap to wake

• latest changes of LineageOS

ROM

2019-05-10

• fixed wifi after fresh installation

• changed scheduler to bfq

• added wireless display broadcast

• improved performance

• removed ril elements from X704F variant

• security patch level: 2019-05-05

ROM

SIM fix for X704L

2019-04-30

• fixed fingerprint bug caused by SELinux

• removed PS3/PS4 controller hid, as it doesn't work

• optimized performance

ROM

2019-04-28

• fixed notifcation led (light was only red for notifications)

• fixed ril values

• added support for PS3/PS4 controller

• SELinux is enforced after boot

ROM

2019-04-24

• fixed hall sensor

• fixed camera

• fixed long time to wake up screen

ROM

2019-04-22

• fixed fingerprint removement after reboot/user switch

• fixed partially camera (same like in 15.1)

• fixed reboot to recovery and bootloader for advanced reboot menu

• fixed long time to wake up screen

• fixed deep sleep

ROM

2019-04-21

• intital release

• TB-X704L is now integrated, no more additional zip required

• You can update from previous version

ROM

Optional downloads

Dolby Digital Plus (use the TWRP one)

GAPPS (use 9.0 arm64; I suggest using pico variant)

Mounting system rw

This is impossible on our tablet. The bootloader enforces verity check, which causes this issue.

The only possibility is to modify bootloader, what is dangerous and requires good knowledge.

there is a workaround using magisk with a mod. which mounts your system rw on mount:

https://xdaforums.com/showpost.php?p=79681018&postcount=259

Thanks

[MENTION=7737930]highwaystar_ru[/MENTION] (he gave me the important hint, also used his sources and his thread :o)

[MENTION=9583233]LumenReaper[/MENTION] (for his work with CM14.1, where I took big part of his device tree :fingers-crossed:)

[MENTION=7116958]Flowah123[/MENTION] for the TB-X704L files :fingers-crossed:

Donations

Thanks to [MENTION=2617299]rorzer[/MENTION], [MENTION=4293254]Preyer11[/MENTION], [MENTION=2717200]Tschumi[/MENTION], [MENTION=426402]MrMagic[/MENTION], [MENTION=9670747]max_work[/MENTION], [MENTION=2065626]vicenza[/MENTION] & 5 x anonymous :D

Please don't support Lenovo and buy their tablets

[I]Updates vary depending on the model where our tablets receive Android and security updates after the introduction.
We announced Tab 4 10 Plus in February 2017 and since then it has received seven OTA updates.
However, this model has reached the end of its update cycle and will not receive any more updates in the future.
- Lenovo (2018-05-11)[/I]

Just seven updates and not even one major upgrade, please don't support them.

Reporting bugs

Please tell what mods you are using and what tablet variant (TB-X704F or L or ABCDEFGH..)

If your tablet doesnt start:

go to TWRP. use file manager, go to sys/fs/pstore, copy the files and upload it here.

if your tablet starts and bug appears later:

go to TWRP. use file manager, go to sys/fs/pstore, copy the files

start your tablet normal, let the bug appear, enter adb root

use adb logcat and adb shell dmesg, copy the content to a text file and upload here

XDA:DevDB Information

[ROM][UNOFFICIAL][9.0][TB-X704F/L] LineageOS 16.0 for Lenovo Tab4 10 Plus, ROM for the Lenovo Thinkpad Tablet

Contributors

yener90, codeworkx

ROM OS Version: 9.x Pie

Version Information

Status: Testing

Created 2019-04-21

Last Updated 2019-06-11