I have tested with 5.2.0, it seems to work. I have the hardware (Atlys shown here: https://hdmi2usb.tv/digilent-atlys/ and sometimes https://store.digilentinc.com/atlys-spartan-6-fpga-trainer-board-limited-time-see-nexys-video/
Are there any issues blocking this? Here is from my bash_history: mkdir shenki torvalds (cd shenki git clone https://github.com/shenki/linux.git cd linux git diff HEAD^ > ../../vizzini.patch ) cd torvalds git clone -depth 1 git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git cd linux cp /boot/config-`uname -r` .config yes '' | make oldconfig make -j `getconf _NPROCESSORS_ONLN` deb-pkg LOCALVERSION=-viz-torv git apply ../../vizzini.patch make oldconfig # USB Exar XR21V141x 'Vizzini' Serial Driver (USB_SERIAL_VIZZINI) [N/m/?] (NEW) m make -j `getconf _NPROCESSORS_ONLN` deb-pkg LOCALVERSION=-viz2-torv cd .. sudo dpkg -i linux-image-5.2.0-rc1-viz2-torv_5.2.0-rc1-viz2-torv-1_amd64.deb -- Carl K