Re: [PATCH v2] ALSA: usb-audio: Add support for Pioneer DJ DJM-S11

[Takashi Iwai <tiwai@suse.de>]

On Thu, 25 Jun 2026 13:46:28 +0200,
Federico Beffa wrote:
> 
> The Pioneer DJ DJM-S11, a professional 2-port DJ mixer, is currently not
> recognized as an audio interface and therefore not usable on Linux. This
> patch enables its full audio functionality.
> 
> Like other mixers in the Pioneer DJ DJM family, the DJM-S11 uses
> vendor-specific USB class descriptors (0xff) and requires custom mixer
> quirks to expose the hardware's input capture routing and volume
> controls.
> 
> Add the USB vendor and product ID (2b73:0037) to quirks-table.h, mapping
> the control interface (Interface 0) to trigger the standard mixer quirks,
> and establishing the audio formats for the playback and capture streams.
> 
> Control interface 3 is likely related to the touchscreen which is
> capable to display waveforms, etc. This functionality is not supported.
> 
> In mixer_quirks.c, add the DSP routing options for the DJM-S11. This
> creates the ALSA kcontrols for selecting the capture sources (Phono,
> Line, Post-fader, etc.) and initializes the default DSP state during
> the device probe.
> 
> Note that the DJM-S11's capture endpoint clock is strictly slaved to
> its playback endpoint. Capturing audio (e.g., timecode vinyl DVS input)
> physically requires an active playback stream on the output channels
> to feed the master word clock back to the capture stage. Userspace
> audio servers (such as PipeWire or JACK) should be configured in
> full-duplex mode or have automatic node suspension disabled to maintain
> the clock line and prevent I/O errors during capture.
> 
> Signed-off-by: Federico Beffa <beffa@fbengineering.ch>

Applied to for-next branch now.  Thanks.


Takashi