ThEMarD

# Begin Open GApps Install Log
------------------------------------------------------------------
            ROM Android version | 9
                   ROM Build ID | lineage_x2-userdebug 9 PPR2.181005.003 1cdc875df4 test-keys
          ROM Version increment | 1cdc875df4
                ROM SDK version | 28
        ROM/Recovery modversion | 16.0-20181018-UNOFFICIAL-x2
                Device Recovery | TWRP 3.2.3-1-32aef7a2
                    Device Name | le_x2
                   Device Model | x2

ThEMarD

Some stock ROMs don't want you using audio logcat level 7 which is required for the audio logs... so for that? You'll need to root your stock ROM with something like Magisk and then use adb with these commands:

adb shell
su
stop
setprop sys.init_log_level 7
logcat -G 4M
start
exit

ThEMarD

First you'll need to clone acdb_extract. I used the one by J510-Dev which is originally based on the one by luca020400.

git clone https://github.com/J510-Dev/acdb_extract

Then, as the README says you must generate the acdb header. For Qualcomm devices? The stock audio hal would be audio.primary.msm8996.so which is found on my stock ROM from /system/lib/hw/audio.primary.msm8996.so which I could just copy into the acdb_get folder... so for example, I'd use this:
./generate_acdb_data.sh audio.primary.msm8996.so

which will generate a file called acdb_data.h which is needed for the next step.

Since acdb_extract doesn't require being built in the AOSP environment? You can just build it using...

ThEMarD

Computer Information:
    Manufacturer:  Unknown
    Model:  Unknown
    Form Factor: Desktop
    No Touch Input Detected

Processor Information:
    CPU Vendor:  GenuineIntel
    CPU Brand:         Intel(R) Core(TM) i7-3770K CPU @ 3.50GHz
    CPU Family:  0x6

ThEMarD

Create a dummy folder to Kang blobs like

device/dummy/dummy

Then copy proprietary-files.txt, extract-files.sh and setup-makefiles.sh from any device. A device that doesn't use a shared commonized device tree does make it easier.

Rename the stuff in the two .sh files to dummy as vendor and device name.

Update necessary proprietary-files in dunmy device tree for kang

ThEMarD

# begin build properties
# autogenerated by buildinfo.sh
ro.letv.release.tag=
ro.letv.product.info=
ro.letv.release.branch=s2_stable_5.9_20161010
ro.letv.release.date=2018-09-09
ro.letv.eui=5.9
ro.letv.release.version=6.0.030S
ro.le.mtpname=Le 2

ThEMarD

# begin build properties
# autogenerated by buildinfo.sh
ro.letv.release.branch=ruby_dev_leui
ro.letv.release.version=6.0.030S
ro.letv.release.version_date=5.8.001D_09093
ro.product.letv_model=Le X820
ro.product.letv_name=乐Max2
ro.build.id=FEXCNFN6003009092S
ro.build.display.id=FEXCNFN6003009092S release-keys

ThEMarD

# begin build properties
# autogenerated by buildinfo.sh
ro.letv.release.branch=ruby_dev_leui
ro.letv.release.version=6.0.030S
ro.letv.release.version_date=5.8.001D_09093
ro.product.letv_model=
ro.product.letv_name=
ro.build.id=WAXCNFN6003009091S
ro.build.display.id=WAXCNFN6003009091S release-keys

ThEMarD

Make sure the device's and/or commonized device proprietary-files are updated with the same blobs that you want in your proprietary vendor repo.

In my example, I'll use the LeEco Le Max 2 (x2), so I would then copy the current LeEco msm8996-common and then x2 blobs (just to clarify, I mean the blobs themselves within the proprietary folder) to the desktop in a folder named vendorblobs

Then open terminal in the device tree and...

./extract-files.sh ~/Desktop/vendorblobs/ | tee ~/Desktop/extractor.log

Check extractor.log to ensure it worked ok and there was no errors / not found.

ThEMarD

If you've installed adb and fastboot via apt install on Ubuntu and realize they're old versions, then here is how to manually update them.

wget https://dl.google.com/android/repository/platform-tools-latest-linux.zip
unzip \platform-tools-latest-linux.zip
sudo cp platform-tools/adb /usr/lib/android-sdk/platform-tools/
sudo cp platform-tools/fastboot /usr/lib/android-sdk/platform-tools/

check that it worked with:

adb --version