The following instructions cover the driver compiling process for RED bean on devices running Linux. We recommend using Debian or Ubuntu. It also might be possible to compile on OSX. Compiling directly on a Windows platform is not supported. However, if all you have available is a windows machine then we would recommend to set up a linux based virtual machine.

1. Prepare build environment by official Android guide

sudo apt-get update
sudo apt-get install openjdk-8-jdk
sudo apt-get install dosfstools genisoimage bc libssl-dev python2.7 python-mako git-core gnupg flex bison gperf build-essential zip curl zlib1g-dev gcc-multilib g++-multilib libc6-dev-i386 lib32ncurses5-dev x11proto-core-dev libx11-dev lib32z-dev libgl1-mesa-dev libxml2-utils xsltproc unzip

2. Install Repo:

mkdir ~/bin
PATH=~/bin:$PATH
curl https://storage.googleapis.com/git-repo-downloads/repo > ~/bin/repo
chmod a+x ~/bin/repo

3. Checkout Android Sources

mkdir android-raspberry; cd android-raspberry
repo init -u https://android.googlesource.com/platform/manifest -b android-7.1.2_r36
git clone https://github.com/android-rpi/local_manifests .repo/local_manifests
repo sync -j$(nproc)

4. Setup environment variables

sudo ln -s /sbin/mkdosfs /home/${USER}/bin/
source build/envsetup.sh
lunch rpi3-eng

5. Build Kernel

cd kernel/rpi
ARCH=arm scripts/kconfig/merge_config.sh arch/arm/configs/bcm2709_defconfig android/configs/android-base.cfg android/configs/android-recommended.cfg
PATH=$ANDROID_BUILD_PATHS$PATH ARCH=arm CROSS_COMPILE=arm-linux-androideabi- make zImage dtbs -j$(nproc)

6. Get the latest qcacld-2.0 sources from 8devices:

cd ~
git clone https://github.com/8devices/qcacld-2.0.git -b caf-wlan/LNX.LEH.4.2.2.2
cd qcacld-2.0

7. Build qcacld-driver module

PATH=$ANDROID_BUILD_PATHS$PATH KERNEL_SRC=$ANDROID_BUILD_TOP/kernel/rpi/ ARCH=arm CROSS_COMPILE=arm-linux-androideabi- make wlan-sdio -j$(nproc)

8. Include driver into Android build system

mkdir $ANDROID_BUILD_TOP/device/brcm/rpi3/firmware/qcacld-2.0
ln -s $PWD/firmware/{usb,sdio} $ANDROID_BUILD_TOP/device/brcm/rpi3/firmware/qcacld-2.0
ln -s $PWD/wlan-{usb,sdio}.ko $ANDROID_BUILD_TOP/device/brcm/rpi3/firmware/qcacld-2.0

9. Patch for auto-loading

patch -p1 -d $ANDROID_BUILD_TOP/device/brcm/rpi3/ < android-patches/0001-load-usb-driver.patch
patch -p1 -d $ANDROID_BUILD_TOP/device/brcm/rpi3/ < android-patches/0002-add-usb-blobs.patch

10. Build Android source

cd ~/android-raspberry
make ramdisk systemimage -j$(nproc)

11. Prepare SD card

Partitions of the card should be set-up like followings.
p1 512MB for BOOT : Do fdisk : W95 FAT32(LBA) & Bootable, mkfs.vfat
p2 512MB for /system : Do fdisk, new primary partition
p3 512MB for /cache  : Do fdisk, mkfs.ext4
p4 remainings for /data : Do fdisk, mkfs.ext4

12. Mount BOOT partition as /mnt/p1 then copy files

cp $ANDROID_BUILD_TOP/device/brcm/rpi3/boot/*  /mnt/p1/
cp $ANDROID_BUILD_TOP/kernel/rpi/arch/arm/boot/zImage /mnt/p1/
cp $ANDROID_BUILD_TOP/kernel/rpi/arch/arm/boot/dts/bcm2710-rpi-3-b.dtb /mnt/p1/
cp $ANDROID_BUILD_TOP/kernel/rpi/arch/arm/boot/dts/overlays/vc4-kms-v3d.dtbo /mnt/p1/overlays/vc4-kms-v3d.dtbo
cp $ANDROID_BUILD_TOP/out/target/product/rpi3/ramdisk.img /mnt/p1/

13. Write system partition

sudo dd if=$ANDROID_BUILD_TOP/out/target/product/rpi3/system.img of=/dev/<p2> bs=1M

14. Once you have android up and runnning, insert the module with:

insmod /lib/modules/wlan-sdio.ko