Asus ZenPad 8 (asus-p024)

Features
Flashing Whether it is possible to flash the device with pmbootstrap flasher.	Works
USB Networking After connecting the device with USB to your PC, you can connect to it via telnet (initramfs) or SSH (booted system).	Works
Battery Whether charging and battery level reporting work.	Broken
Screen Whether the display works; ideally with sleep mode and brightness control.	Works
Touchscreen	Works
Multimedia
3D Acceleration	Untested
Audio Audio playback, microphone, headset and buttons.	Broken
Camera	Untested
Connectivity
WiFi	Broken
Bluetooth	Untested
GPS	Untested
Modem
Calls	Untested
SMS	Untested
Mobile data	Untested
Miscellaneous
FDE Full disk encryption and unlocking with unl0kr.	Untested
USB OTG USB On-The-Go or USB-C Role switching.	Works
Sensors
Accelerometer Handles automatic screen rotation in many interfaces.	Untested

Asus ZenPad 8.0 (Z380KL)
	; Asus ZenPad 8.0 running Xfce
Manufacturer	Asus
Name	ZenPad 8.0 (Z380KL)
Codename	asus-p024
Released	2015
Type	tablet
Hardware
Chipset	Qualcomm Snapdragon 410 (MSM8916)
CPU	Quad-core Cortex-A53 1.2 GHz
GPU	Adreno 306
Display	1280x800 IPS LCD
Storage	16 GB
Memory	1 GB
Architecture	armv7
Software
Original software The software and version the device was shipped with.	Android 5.0
Extended version The most recent supported version from the manufacturer.	Android 6
postmarketOS
Category	archived
Mainline Instead of a Linux kernel fork, it is possible to run (Close to) Mainline.	no
Device package	device-asus-p024
Kernel package	linux-postmarketos-qcom-msm8916

This device has been archived. This means that it no longer appears in pmbootstrap and is likely broken.
It can still be selected in pmbootstrap init by typing in the vendor and codename, but you will have to build the kernel package manually.

The marketing name seems to be "Asus ZenPad 8.0", which is abbreviated as Z380KL. The codename (listed by the FCC) seems to be P024

Contributors

Radmir Far

Users owning this device

Radmir Far

Preliminary steps

Download firmware file

In Settings/About/Software information take note of the build number, amongst other things it contains a string like WW_P024-V4.8.2, indicating firmware version (eg. V4.8.2) and the SKU (eg. WW).
Download the corresponding upgrade file from Asus support page.
From the downloaded file, extract the boot.img file, needed for dual booting.

Unlock the bootloader

Tested on: Android 5.0.2/Firmware 4.8.2

Add your Android/Firmware combo to the list if it works, or edit the instructions in case of differences.

Boot your tablet to Recovery/Fastboot mode by holding Volume Up while powering up.
fastboot oem unlock
On older Android devices there is no warning in case of unlocked bootloader, check if fastboot oem device-info contains Device unlocked: true as confirmation.

How to enter flash mode

With the device powered off, hold Volume Up + Power.

Installation

lk2nd

lk2nd is a secondary bootloader that provides a standard fastboot interface, which can be used to boot postmarketOS without Android boot flashed or pmbootstrap flasher flash_kernel.

Download lk2nd-msm8916.img from Releases page on Github.
Boot your phone to bootloader (fastboot) mode.
Follow lk2nd instructions to install lk2nd. Basically flash it to the boot partition (fastboot flash boot lk2nd-msm8916.img)
Follow Qualcomm_Snapdragon_410/412_(MSM8916)#Installation to install postmarketOS.

Note: Enter lk2nd fastboot mode by pressing Volume Down after booting (this time wait until it vibrates then press Volume Down!

Dual boot

To dual boot Android and PostmarketOS, after lk2nd install:

enter in lk2nd`s fastboot mode by pressing Volume Down after booting (do NOT use the stock recovery, it would overwrite lk2nd)
Flash the original boot.img obtained in preliminary steps with fastboot flash boot boot.img
Now the tablet should boot PostmarketOS from SD card, or Android if there is no SD.

What doesn't work

Battery level reporting seems to be broken.