On 11/12/18 07:30, Colin Bortner wrote:
Hello,
I’d like to use OpenBSD to build a MIDI synthesizer using SoundFonts, as the
OpenBSD MIDI and audio subsystems are remarkably understandable and sane,
compared to everything else out there today.
I’ve heard a fair bit here about USB audio not working very well, or at all, in
-stable right now. I’m unsure if this only applies to XHCI ports or not?
As far as I know isochronous transfer mode required by USB audio class devices
is not supported by the xhci driver. I believe a few people are poking at this,
but that doesn't mean there will be support anytime soon. However - not all is
lost...
For the NUC, USB 3.0 can be disabled in the bios, forcing the ehci driver, and
allowing me to use the USB DAC without issues.
Alas, the UCA-202 hangs...
uaudio0 at uhub0 port 3 configuration 1 interface 0 "Burr-Brown from TI USB Audio
CODEC" rev 1.10/1.00 addr 7
uaudio0: audio rev 1.00, 2 mixer controls
audio1 at uaudio0
uhidev3 at uhub0 port 3 configuration 1 interface 3 "Burr-Brown from TI USB Audio
CODEC" rev 1.10/1.00 addr 7
uhidev3: iclass 3/0
uhid0 at uhidev3: input=1, output=0, feature=0
uaudio_chan_open: error creating pipe: err=INVAL endpt=0x02
audio1: failed to start playback
Disabling xhci allows it to run.
I'd love to fix isochronous mode in my Infinite Spare Time...
once I learn the USB stack & hang my machine 100+ times,
submit the code and get very embarrassed, try again...
Very likely many of the developers who are much more familiar with
the USB stack would like to fix it in their Infinite Spare Time.
Geoff Steckel
