Merge branch 'topic/midi20' into for-next

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.

Link: https://lore.kernel.org/r/20230523075358.9672-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 60 insertions, 2 deletions

diff --git a/include/uapi/sound/asound.h b/include/uapi/sound/asound.h
index 6322823b5270..409069b519fe 100644
--- a/include/uapi/sound/asound.h
+++ b/include/uapi/sound/asound.h
@@ -712,7 +712,7 @@ enum {
  *  Raw MIDI section - /dev/snd/midi??
  */
 
-#define SNDRV_RAWMIDI_VERSION		SNDRV_PROTOCOL_VERSION(2, 0, 2)
+#define SNDRV_RAWMIDI_VERSION		SNDRV_PROTOCOL_VERSION(2, 0, 3)
 
 enum {
 	SNDRV_RAWMIDI_STREAM_OUTPUT = 0,
@@ -723,6 +723,7 @@ enum {
 #define SNDRV_RAWMIDI_INFO_OUTPUT		0x00000001
 #define SNDRV_RAWMIDI_INFO_INPUT		0x00000002
 #define SNDRV_RAWMIDI_INFO_DUPLEX		0x00000004
+#define SNDRV_RAWMIDI_INFO_UMP			0x00000008
 
 struct snd_rawmidi_info {
 	unsigned int device;		/* RO/WR (control): device number */
@@ -783,6 +784,57 @@ struct snd_rawmidi_status {
 };
 #endif
 
+/* UMP EP Protocol / JRTS capability bits */
+#define SNDRV_UMP_EP_INFO_PROTO_MIDI_MASK	0x0300
+#define SNDRV_UMP_EP_INFO_PROTO_MIDI1		0x0100 /* MIDI 1.0 */
+#define SNDRV_UMP_EP_INFO_PROTO_MIDI2		0x0200 /* MIDI 2.0 */
+#define SNDRV_UMP_EP_INFO_PROTO_JRTS_MASK	0x0003
+#define SNDRV_UMP_EP_INFO_PROTO_JRTS_TX		0x0001 /* JRTS Transmit */
+#define SNDRV_UMP_EP_INFO_PROTO_JRTS_RX		0x0002 /* JRTS Receive */
+
+/* UMP Endpoint information */
+struct snd_ump_endpoint_info {
+	int card;			/* card number */
+	int device;			/* device number */
+	unsigned int flags;		/* additional info */
+	unsigned int protocol_caps;	/* protocol capabilities */
+	unsigned int protocol;		/* current protocol */
+	unsigned int num_blocks;	/* # of function blocks */
+	unsigned short version;		/* UMP major/minor version */
+	unsigned short padding[7];
+	unsigned char name[128];	/* endpoint name string */
+	unsigned char product_id[128];	/* unique product id string */
+	unsigned char reserved[32];
+} __packed;
+
+/* UMP direction */
+#define SNDRV_UMP_DIR_INPUT		0x01
+#define SNDRV_UMP_DIR_OUTPUT		0x02
+#define SNDRV_UMP_DIR_BIDIRECTION	0x03
+
+/* UMP block info flags */
+#define SNDRV_UMP_BLOCK_IS_MIDI1	(1U << 0) /* MIDI 1.0 port w/o restrict */
+#define SNDRV_UMP_BLOCK_IS_LOWSPEED	(1U << 1) /* 31.25Kbps B/W MIDI1 port */
+
+/* UMP groups and blocks */
+#define SNDRV_UMP_MAX_GROUPS		16
+#define SNDRV_UMP_MAX_BLOCKS		32
+
+/* UMP Block information */
+struct snd_ump_block_info {
+	int card;			/* card number */
+	int device;			/* device number */
+	unsigned char block_id;		/* block ID (R/W) */
+	unsigned char direction;	/* UMP direction */
+	unsigned char active;		/* Activeness */
+	unsigned char first_group;	/* first group ID */
+	unsigned char num_groups;	/* number of groups */
+	unsigned char padding[3];
+	unsigned int flags;		/* various info flags */
+	unsigned char name[128];	/* block name string */
+	unsigned char reserved[32];
+} __packed;
+
 #define SNDRV_RAWMIDI_IOCTL_PVERSION	_IOR('W', 0x00, int)
 #define SNDRV_RAWMIDI_IOCTL_INFO	_IOR('W', 0x01, struct snd_rawmidi_info)
 #define SNDRV_RAWMIDI_IOCTL_USER_PVERSION _IOW('W', 0x02, int)
@@ -790,6 +842,9 @@ struct snd_rawmidi_status {
 #define SNDRV_RAWMIDI_IOCTL_STATUS	_IOWR('W', 0x20, struct snd_rawmidi_status)
 #define SNDRV_RAWMIDI_IOCTL_DROP	_IOW('W', 0x30, int)
 #define SNDRV_RAWMIDI_IOCTL_DRAIN	_IOW('W', 0x31, int)
+/* Additional ioctls for UMP rawmidi devices */
+#define SNDRV_UMP_IOCTL_ENDPOINT_INFO	_IOR('W', 0x40, struct snd_ump_endpoint_info)
+#define SNDRV_UMP_IOCTL_BLOCK_INFO	_IOR('W', 0x41, struct snd_ump_block_info)
 
 /*
  *  Timer section - /dev/snd/timer
@@ -965,7 +1020,7 @@ struct snd_timer_tread {
  *                                                                          *
  ****************************************************************************/
 
-#define SNDRV_CTL_VERSION		SNDRV_PROTOCOL_VERSION(2, 0, 8)
+#define SNDRV_CTL_VERSION		SNDRV_PROTOCOL_VERSION(2, 0, 9)
 
 struct snd_ctl_card_info {
 	int card;			/* card number */
@@ -1126,6 +1181,9 @@ struct snd_ctl_tlv {
 #define SNDRV_CTL_IOCTL_RAWMIDI_NEXT_DEVICE _IOWR('U', 0x40, int)
 #define SNDRV_CTL_IOCTL_RAWMIDI_INFO	_IOWR('U', 0x41, struct snd_rawmidi_info)
 #define SNDRV_CTL_IOCTL_RAWMIDI_PREFER_SUBDEVICE _IOW('U', 0x42, int)
+#define SNDRV_CTL_IOCTL_UMP_NEXT_DEVICE	_IOWR('U', 0x43, int)
+#define SNDRV_CTL_IOCTL_UMP_ENDPOINT_INFO _IOWR('U', 0x44, struct snd_ump_endpoint_info)
+#define SNDRV_CTL_IOCTL_UMP_BLOCK_INFO	_IOWR('U', 0x45, struct snd_ump_block_info)
 #define SNDRV_CTL_IOCTL_POWER		_IOWR('U', 0xd0, int)
 #define SNDRV_CTL_IOCTL_POWER_STATE	_IOR('U', 0xd1, int)