Hi,
this is a (largish) patch set for adding the support of MIDI 2.0 functionality, mainly targeted for USB devices. MIDI 2.0 is a complete overhaul of the 40-years old MIDI 1.0. Unlike MIDI 1.0 byte stream, MIDI 2.0 uses packets in 32bit words for Universal MIDI Packet (UMP) protocol. It supports both MIDI 1.0 commands for compatibility and the extended MIDI 2.0 commands for higher resolutions and more functions.
For supporting the UMP, the patch set extends the existing ALSA rawmidi and sequencer interfaces, and adds the USB MIDI 2.0 support to the standard USB-audio driver.
The rawmidi for UMP has a different device name (/dev/snd/umpC*D*) and it reads/writes UMP packet data in 32bit CPU-native endianness. For the old MIDI 1.0 applications, the legacy rawmidi interface is provided, too.
As default, USB-audio driver will take the alternate setting for MIDI 2.0 interface, and the compatibility with MIDI 1.0 is provided via the rawmidi common layer. However, user may let the driver falling back to the old MIDI 1.0 interface by a module option, too.
A UMP-capable rawmidi device can create the corresponding ALSA sequencer client(s) to support the UMP Endpoint and UMP Group connections. As a nature of ALSA sequencer, arbitrary connections between clients/ports are allowed, and the ALSA sequencer core performs the automatic conversions for the connections between a new UMP sequencer client and a legacy MIDI 1.0 sequencer client. It allows the existing application to use MIDI 2.0 devices without changes.
The MIDI-CI, which is another major extension in MIDI 2.0, isn't covered by this patch set. It would be implemented rather in user-space.
Roughly speaking, the first half of this patch set is for extending the rawmidi and USB-audio, and the second half is for extending the ALSA sequencer interface.
The patch set is based on 6.4-rc2 kernel, but all patches can be cleanly applicable on 6.2 and 6.3 kernels, too (while 6.1 and older kernels would need minor adjustment for uapi header changes).
The updates for alsa-lib and alsa-utils will follow shortly later.
The author thanks members of MIDI Association OS/API Working Group, especially Andrew Mee, for great helps for the initial design and debugging / testing the drivers.
Takashi
---
Takashi Iwai (36): ALSA: rawmidi: Pass rawmidi directly to snd_rawmidi_kernel_open() ALSA: rawmidi: Add ioctl callback to snd_rawmidi_global_ops ALSA: rawmidi: UMP support ALSA: rawmidi: Skip UMP devices at SNDRV_CTL_IOCTL_RAWMIDI_NEXT_DEVICE ALSA: ump: Additional proc output ALSA: usb-audio: Manage number of rawmidis globally ALSA: usb-audio: Define USB MIDI 2.0 specs ALSA: usb-audio: USB MIDI 2.0 UMP support ALSA: usb-audio: Get UMP EP name string from USB interface ALSA: usb-audio: Trim superfluous "MIDI" suffix from UMP EP name ALSA: usb-audio: Create UMP blocks from USB MIDI GTBs ALSA: ump: Redirect rawmidi substream access via own helpers ALSA: ump: Add legacy raw MIDI support ALSA: usb-audio: Enable the legacy raw MIDI support ALSA: usb-audio: Inform inconsistent protocols in GTBs ALSA: seq: Clear padded bytes at expanding events ALSA: seq: Add snd_seq_expand_var_event_at() helper ALSA: seq: Treat snd_seq_client object directly in client drivers ALSA: seq: Drop dead code for the old broadcast support ALSA: seq: Check the conflicting port at port creation ALSA: seq: Check validity before creating a port object ALSA: seq: Prohibit creating ports with special numbers ALSA: seq: Introduce SNDRV_SEQ_IOCTL_USER_PVERSION ioctl ALSA: seq: Add UMP support ALSA: seq: Add port inactive flag ALSA: seq: Support MIDI 2.0 UMP Endpoint port ALSA: seq: Add port direction to snd_seq_port_info ALSA: seq: Add UMP group number to snd_seq_port_info ALSA: seq: Automatic conversion of UMP events ALSA: seq: Allow suppressing UMP conversions ALSA: seq: Bind UMP device ALSA: seq: ump: Create UMP Endpoint port for broadcast ALSA: seq: Add ioctls for client UMP info query and setup ALSA: seq: Print UMP Endpoint and Block information in proc outputs ALSA: seq: Add UMP group filter ALSA: docs: Add MIDI 2.0 documentation
Documentation/sound/designs/index.rst | 1 + Documentation/sound/designs/midi-2.0.rst | 342 ++++++ include/linux/usb/midi-v2.h | 94 ++ include/sound/asequencer.h | 4 + include/sound/rawmidi.h | 16 +- include/sound/seq_device.h | 1 + include/sound/seq_kernel.h | 10 + include/sound/ump.h | 175 ++++ include/sound/ump_msg.h | 540 ++++++++++ include/uapi/sound/asequencer.h | 83 +- include/uapi/sound/asound.h | 58 +- sound/core/Kconfig | 13 + sound/core/Makefile | 3 + sound/core/rawmidi.c | 233 +++-- sound/core/rawmidi_compat.c | 4 + sound/core/seq/Kconfig | 14 + sound/core/seq/Makefile | 3 + sound/core/seq/seq_clientmgr.c | 577 +++++++---- sound/core/seq/seq_clientmgr.h | 27 +- sound/core/seq/seq_compat.c | 3 + sound/core/seq/seq_dummy.c | 9 + sound/core/seq/seq_memory.c | 98 +- sound/core/seq/seq_memory.h | 19 +- sound/core/seq/seq_midi.c | 12 +- sound/core/seq/seq_ports.c | 46 +- sound/core/seq/seq_ports.h | 23 +- sound/core/seq/seq_ump_client.c | 464 +++++++++ sound/core/seq/seq_ump_convert.c | 1203 ++++++++++++++++++++++ sound/core/seq/seq_ump_convert.h | 22 + sound/core/seq/seq_virmidi.c | 1 + sound/core/ump.c | 677 ++++++++++++ sound/core/ump_convert.c | 520 ++++++++++ sound/core/ump_convert.h | 43 + sound/usb/Kconfig | 11 + sound/usb/Makefile | 1 + sound/usb/card.c | 12 +- sound/usb/midi.c | 7 +- sound/usb/midi.h | 5 +- sound/usb/midi2.c | 1189 +++++++++++++++++++++ sound/usb/midi2.h | 33 + sound/usb/quirks.c | 8 +- sound/usb/usbaudio.h | 2 + 42 files changed, 6274 insertions(+), 332 deletions(-) create mode 100644 Documentation/sound/designs/midi-2.0.rst create mode 100644 include/linux/usb/midi-v2.h create mode 100644 include/sound/ump.h create mode 100644 include/sound/ump_msg.h create mode 100644 sound/core/seq/seq_ump_client.c create mode 100644 sound/core/seq/seq_ump_convert.c create mode 100644 sound/core/seq/seq_ump_convert.h create mode 100644 sound/core/ump.c create mode 100644 sound/core/ump_convert.c create mode 100644 sound/core/ump_convert.h create mode 100644 sound/usb/midi2.c create mode 100644 sound/usb/midi2.h