In the past Intel Atom based mini PCs with Bay Trail and Cherry Trail SOCs required customized kernels to provide HDMI audio. As of version 4.11 the mainline kernel will include support for HDMI audio on Intel Atom SoCs and early release candidates are already available. The latest mainline kernel also includes a number of other patches including AXP288, I2C and the latest anti-freeze patches. Canonical build upstream kernels based on these release candidates and they have just released 'deb' packages using the first Ubuntu version 4.11 kernel configuration file.
In anticipation that the v4.11 kernel will be included in Ubuntu 17.10 thereby removing the basic need for customized kernels, I am now providing an interim migration path that allows the latest v4.11 Ubuntu kernel build to be used with Ubuntu ISOs.
Using a script that I've developed you can respin an existing Ubuntu ISO so that you can boot it from a device with either a 32-bit bootloader or a 64-bit bootloader and optionally update it with the latest Canonical Ubuntu build of an upstream kernel.
Linux Mint ISOs are now supported using the updated version of the script isorespin.sh
To respin an existing Ubuntu ISO you will need to use a Linux machine with 'squashfs-tools' and 'xorriso' installed (e.g. 'sudo apt install -y squashfs-tools xorriso') and a working internet connection with at least 10GB of free space. Having downloaded an ISO (for example 'ubuntu-16.04.2-desktop-amd64.iso' simply download my script isorespin.sh (see Update: below for the latest version) and run with the ISO as a parameter (e.g. './isorespin.sh ubuntu-16.04.2-desktop-amd64.iso'). Or to respin and update the kernel include a '-u' or '--update' option (e.g. './isorespin.sh --update ubuntu-16.04.2-desktop-amd64.iso').
You can respin the latest available ISOs include the recently released 17.04 Beta 2 of any flavour including Ubuntu, Lubuntu, Xubuntu etc, as well as respinning earlier releases such as 16.04.2 or 14.04.5 for example.
As some wifi/bluetooth driver and userspace files are still required I've provided additional scripts to support RTL8723BS and various Broadcom chipsets as well as the ALSA UCM files for some audio chipsets used for headphones. The scripts can be run whilst using the ISO as a 'LiveCD' to provide wifi connectivity (assuming they have been previously downloaded and are accessed from USB or similar). Once an ISO has been installed the scripts can be run to install the additional functionality.
For the RTL8723BS chipset your first option is to download and run linuxium-install-rtl8723bs.sh which will build the wifi and bluetooth drivers from source and this requires a working internet connection. Alternatively you can download and run linuxium-install-rtl8723bs-binaries-for-4.11.0-rc4.sh (see Update: below for the latest version) which installs prebuilt binaries from the same source but does not require the internet. This second script only works for the Ubuntu built upstream kernel defined by the script name.
For Broadcom chipsets you can download and run linuxium-install-broadcom-drivers.sh which should get wifi and bluetooth working for most of the popular Broadcom chipsets (as I don't have the devices to do extensive testing unfortunately). If you run this script with an internet connection it will also update the Broadcom firmware with the latest upstream firmware from Google's ChromiumOS which may help for other Broadcom based devices.
Note that in both cases the bluetooth service requires 'systemd' (as used by 17.04 and 16.04) so earlier Ubuntu versions will need a manual configuration to run the service.
Finally for updating the UCM files where you have a headphone jack you will need an internet connection before downloading and running linuxium-install-UCM-files.sh which provides audio for devices with the 5640 and 5640 chipsets.
A new kernel release candidate is released each week prior to the final version and you can go to http://kernel.ubuntu.com/~kernel-ppa/mainline/?C=N;O=D to check the latest version which will be displayed first.
If you want to respin ISOs with a release candidate later than 'rc4' simply edit 'isorespin.sh' and change the first couple of lines
MAINLINE_BRANCH="v4.11-rc4"to match the required version.
Mainline kernel v4.11-rc5 includes a new patch for the RTL8723BS wifi driver that improves speed and reliability. So I've uploaded an updated version of my script isorespin.sh preconfigured for v4.11-rc5 together with a new script linuxium-install-rtl8723bs-binaries-for-4.11.0-rc5.sh which installs the prebuilt wifi and bluetooth binaries compiled for v4.11-rc5. This version of the script now additionally supports Linux Mint ISOs.
Finally if you find my work useful then please donate using the following link http://goo.gl/nXWSGf as everything helps with development costs.