DAC+ Pro Driver on Github
Well, here’s some good news! Our team member Stuart finished the development of the drivers for Linux 4.1, and pushed the new version to Github. The files are located here. Right now, this is only useful for people who want to build their own Linux kernel. We’ll be getting in touch with the Raspberry Pi kernel developers to get the updated driver integrated into the official Raspberry Pi kernel.
With this new driver, the integrated clock generators of the DAC+ Pro will be activated and the board will identify itself as a HiFiBerry DAC+ Pro:
root@raspberrypi:~# aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: sndrpihifiberry [snd_rpi_hifiberry_dacplus], device 0: HiFiBerry DAC+ Pro HiFi pcm512x-hifi-0 
Subdevice #0: subdevice #0
Update 5.10.15: The new driver has been merged into the official Raspberry Pi Linux kernel. If you update your system with rpi-update, you’ll get the new drivers. The kernel version should be at least 4.1.10.