Build WLAN Pi kernel

Sync and build the Kernel for WLAN Pi.

Currently the script downloads the kernel source from Raspberry Pi Linux Github page and does a checkout to specified branch.

Then it applies the patches from kernel-patches folder to this kernel, updates the default defconfig with wlanpi_defconfig, builds the kernel and them packages it on .deb.

Usage:

./build-kernel.sh

To configure the architecture for the cross compilation, use flag --arch with the corresponding arch desired (either arm or arm64). Default option is arm (32 bits).

./build-kernel.sh --arch arm64

To clean the kernel for a new compilation from scratch, use the flag --clean.

./build-kernel.sh --clean

Kernel will only be cloned the first time. If you want to sync again (git fetch) and force the update to latest commit on branch, use the flag --force-sync.

./build-kernel.sh --force-sync

The force update might fail depending on the changes made on the kernel repository. In that case, just use both clean and force update variables together.

To set a different kernel version, use the --branch option, which is the branch on kernel repository (e.g. rpi-5.13.y, rpi-5.15.y, rpi-5.16.y). Default option is rpi-5.15.y.

./build-kernel.sh --branch rpi-5.16.y

To set the number of cores to be used on compilation, use -j flag followed by the number of cores. The default value is half the cores in the system. If used as -jX it will use all cores.

./build-kernel.sh -jX