Killer 1535 uses the included driver in SteamOS, however, the firmware needs to be downloaded and updated.
and put it in the /lib/firmware/ath10k/QCA6174/hw3.0/ folder (create the folder if it doesn’t exist)
http://support.killernetworking.com/K1535_Debian/board.bin and put it in the /lib/firmware/ath10k/QCA6174/hw3.0/ folder as firmware-4.bin.
Create a config file with:
sudo nano /etc/modprobe.d/ath10k.conf
The 1535, 1525, and 1435 use the community developed and supported ath10k driver. Killer Networking neither develops nor supports the ath10k driver. For further support, please refer either to the community support for your specific Linux distribution and version, or the driver itself.