Re: [PATCH 0/3] ALSA: 6fire: S/PDIF output

[Takashi Iwai <tiwai@suse.de>]

On Fri, 16 Oct 2026 09:31:29 +0200,
Piotr Gliźniewicz wrote:
> 
> The DMX 6Fire USB has a coaxial S/PDIF output, which the driver keeps
> disabled. This series enables it as playback channels 7 and 8 of the
> existing PCM device, the layout chosen in the RFC thread [1].
> 
> Patch 1 takes stream_mutex in the "Digital Thru Playback Route" put.
> It fixes a race with prepare that exists in mainline, and patch 3
> depends on the lock.
> 
> Patch 2 adds a playback channel map in the order of the manual of the
> card, FL FR FC LFE RL RR on Line Out 1 to 6.
> 
> Patch 3 adds the output with the "IEC958 Playback Default", "IEC958
> Playback Con Mask" and "IEC958 Playback Switch" controls. With 8
> channels the card runs at 96 kHz at most. The Pro Audio profile of
> PipeWire 1.6.9 opened the device with 8 channels, so with this series
> it gets 8 channels at up to 96 kHz instead of 6 channels at up to
> 192 kHz. A client that asks for 6 channels still gets 176.4 and
> 192 kHz.
> 
> A UCM profile for alsa-ucm-conf will describe the channels: the default
> variant with analog 5.1 and S/PDIF as two sinks at up to 96 kHz, and a
> "HiFi Analog" variant with analog 5.1 only at up to 192 kHz, which
> turns the switch off while in use. I tested a draft with
> PipeWire 1.6.9 and this series; I will send it after the kernel
> patches are accepted.
> 
> [1] https://lore.kernel.org/linux-sound/30dcedc7-3b56-4396-af3d-6c2701ef1cb7@perex.cz/
> 
> Piotr Gliźniewicz (3):
>   ALSA: 6fire: take stream_mutex in the Digital Thru control
>   ALSA: 6fire: add a playback channel map
>   ALSA: 6fire: add S/PDIF output

Applied to for-next branch now.  Thanks.


Takashi