NVIDIA Jetson-AGX L4T 32.7.4 [ JetPack UNKNOWN ] Ubuntu 18.04.6 LTS Kernel Version: 4.9.337-tegra
(1) Update Below
midi keyboard attaches to
snd-usb-audiodriver via USB, can see it with
lsusb -t. Don’t think that’s the right driver, no ALSA tools can see it (ALSA tools don’t work at first) and no software is properly taking in it’s input.
all ALSA midi tools require a
/dev/snd/seq, which isn’t present, they all fail with error.
I download kernel, build kernel, build modules for
CONFIG_SND_SEQUENCER, had to edit source because one function in a file (
sound/core/seq/seq_ports.c) was defined twice, so I removed one copy.
make && make prepare_modules modules install install_moduleswithout error.
Doesn’t seem to install correctly, had to manually set some links and stuff.
uname -rnever changed to 4.9.337+, as new files and folders were named by Makefile. Separate issue but would love to get into it
Worked in that
/dev/snd/seqnow exists and
...seq_midistuff but keyboard still not recognized as input by ALSA utilities.
Any solutions? Should I just upgrade entire setup?
make installhere is broken, some copying Image manually solved the issue of properly updating the
uname -rresponse. Also updated the device tree binaries.
USB Audio/MIDIis working and
cat /dev/snd/midiC2D0shows it’s responding to keyboard input. BUT…
- Most applications look for ALSA
dev/snd/seqinterface, not the one that’s working. Enabling it as a module, or as compiled in, and/disabling
USB Audio/MIDIin any combination doesn’t work. Even when
dev/snd/seqappears, my piano apps that try to access it freeze,
aconnect -idoesn’t see the keyboard, etc