Quantum

Linux kernel ALSA driver for PreSonus™ Quantum Thunderbolt™ audio interfaces.

Current Support

Currently, only the PreSonus Quantum 2626 is supported. Work is in progress to extend support to the rest of the Quantum product family.

Origin & Attribution

This repository is an out-of-tree build adaptation of the original RFC patch series by Nicholas Johnson (August 20, 2026).

Hi all,

This RFC series adds an ALSA PCI driver for PreSonus Quantum PCIe/Thunderbolt audio interfaces.

This project is independent and is not affiliated with PreSonus or Fender.

The driver provides playback, capture, raw MIDI, sample-rate control, clock-source control, XRUN reporting, and surprise-removal handling. It targets the Quantum PCI family and currently has verified support for the Quantum 2626.

The implementation keeps the hardware path direct and multichannel, with the aim of being small, reviewable, and suitable for eventual upstreaming.

I want to thank my best friend, Ju Ern, for lending me the machine used to develop the driver, and the Asahi Linux project for m1n1 and the tooling that made the hardware tracing and analysis possible.

Only the verified 2626 device ID is matched by the driver at present.

I am sending this as RFC to gather review and testing before asking for merge. I would especially appreciate feedback on ALSA integration, device enumeration, runtime PM/latency handling, and upstream expectations for the driver.

Thanks, Nicholas Johnson

Modifications

This fork adapts the original RFC to support out-of-tree compilation.

• Added a custom Makefile for external building based upon my previous work on Jamie Steele's attempt.
• Driver source code remains unchanged from the original RFC (Quantum 2626 only).
• Next Steps: Refactoring the device detection and initialization logic to support the full Quantum range, building on the foundations laid in Jamie Steele's attempt and my own research.

Development Workflow

This repository serves as a local working tree for out-of-tree building and testing. When contributing changes back to the Linux kernel community, do not send commits directly. Instead, generate standard patch files that exclude local build infrastructure.

Generating Patches for Upstream Submission

To create patch files suitable for the linux-sound mailing list, excluding the root Makefile, README.md, and LICENSE:

# Replace <base-commit> with the hash of the last clean import (e.g., the RFC import commit)
git format-patch <base-commit>..HEAD -- ':!Makefile' ':!README.md' ':!LICENSE'

Sending Patches

Once generated, review the patches and send them via git send-email:

git send-email --to=linux-sound@vger.kernel.org \
  --cc=tiwai@suse.com --cc=perex@perex.cz \
  *.patch

Code Style & Checks

Before generating patches, ensure your code adheres to kernel standards:

# Check for coding style issues
make C=1

# Run static analysis (needs sparse installed)
make C=2

Note: Always mark incomplete features or known issues with // FIXME or // TODO comments in the code. These will be visible in the generated patches and signal to reviewers which parts are work-in-progress.

Usage

Build

make

Install

sudo make install-module
sudo modprobe snd-quantum

Uninstall

sudo rmmod snd-quantum
sudo make uninstall-module

Note

This project is independent and is not affiliated with PreSonus™ or Fender™.