pipewire (0.3.71) code is missing an ALSA rawmidi driver
Raw MIDI is better suited for JACK audio applications than alsa seq midi since JACK MIDI exists.
ALSA seq interface requires additional clock setup so to not have audio/midi drifts, while rawmidi by virtue of just receiving/sending the raw MIDI data from/to the HW, can be bound to the audio processing thread (the one that does the ALSA PCM HW IO) and thus avoid the additional clock drift&jitter.
This is also the reason why first design a2jmidid (a daemon that exposes alsa seq clients in jack midi system) was limited to software only clients. Afterwards people found use of a2jmidid for hardware ports too.
pipewire (0.3.71) code is missing an ALSA rawmidi driver
Raw MIDI is better suited for JACK audio applications than alsa seq midi since JACK MIDI exists.
ALSA seq interface requires additional clock setup so to not have audio/midi drifts, while rawmidi by virtue of just receiving/sending the raw MIDI data from/to the HW, can be bound to the audio processing thread (the one that does the ALSA PCM HW IO) and thus avoid the additional clock drift&jitter.
This is also the reason why first design a2jmidid (a daemon that exposes alsa seq clients in jack midi system) was limited to software only clients. Afterwards people found use of a2jmidid for hardware ports too.