ALSA: usb-audio: Define USB MIDI 2.0 specs

Define new structs and constants from USB MIDI 2.0 specification,
to be used in the upcoming MIDI 2.0 support in USB-audio driver.

A new class-specific endpoint descriptor and group terminal block
descriptors are defined.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Jaroslav Kysela <perex@perex.cz>
Link: https://lore.kernel.org/r/20230523075358.9672-9-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/include/linux/usb/midi-v2.h b/include/linux/usb/midi-v2.h
new file mode 100644 (file)
index 0000000..ebbffca
--- /dev/null
+++ b/include/linux/usb/midi-v2.h
@@ -0,0 +1,94 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * <linux/usb/midi-v2.h> -- USB MIDI 2.0 definitions.
+ */
+
+#ifndef __LINUX_USB_MIDI_V2_H
+#define __LINUX_USB_MIDI_V2_H
+
+#include <linux/types.h>
+#include <linux/usb/midi.h>
+
+/* A.1 MS Class-Specific Interface Descriptor Types */
+#define USB_DT_CS_GR_TRM_BLOCK 0x26
+
+/* A.1 MS Class-Specific Interface Descriptor Subtypes */
+/* same as MIDI 1.0 */
+
+/* A.2 MS Class-Specific Endpoint Descriptor Subtypes */
+#define USB_MS_GENERAL_2_0     0x02
+
+/* A.3 MS Class-Specific Group Terminal Block Descriptor Subtypes */
+#define USB_MS_GR_TRM_BLOCK_UNDEFINED  0x00
+#define USB_MS_GR_TRM_BLOCK_HEADER     0x01
+#define USB_MS_GR_TRM_BLOCK            0x02
+
+/* A.4 MS Interface Header MIDIStreaming Class Revision */
+#define USB_MS_REV_MIDI_1_0            0x0100
+#define USB_MS_REV_MIDI_2_0            0x0200
+
+/* A.5 MS MIDI IN and OUT Jack Types */
+/* same as MIDI 1.0 */
+
+/* A.6 Group Terminal Block Types */
+#define USB_MS_GR_TRM_BLOCK_TYPE_BIDIRECTIONAL 0x00
+#define USB_MS_GR_TRM_BLOCK_TYPE_INPUT_ONLY    0x01
+#define USB_MS_GR_TRM_BLOCK_TYPE_OUTPUT_ONLY   0x02
+
+/* A.7 Group Terminal Default MIDI Protocol */
+#define USB_MS_MIDI_PROTO_UNKNOWN      0x00 /* Unknown (Use MIDI-CI) */
+#define USB_MS_MIDI_PROTO_1_0_64       0x01 /* MIDI 1.0, UMP up to 64bits */
+#define USB_MS_MIDI_PROTO_1_0_64_JRTS  0x02 /* MIDI 1.0, UMP up to 64bits, Jitter Reduction Timestamps */
+#define USB_MS_MIDI_PROTO_1_0_128      0x03 /* MIDI 1.0, UMP up to 128bits */
+#define USB_MS_MIDI_PROTO_1_0_128_JRTS 0x04 /* MIDI 1.0, UMP up to 128bits, Jitter Reduction Timestamps */
+#define USB_MS_MIDI_PROTO_2_0          0x11 /* MIDI 2.0 */
+#define USB_MS_MIDI_PROTO_2_0_JRTS     0x12 /* MIDI 2.0, Jitter Reduction Timestamps */
+
+/* 5.2.2.1 Class-Specific MS Interface Header Descriptor */
+/* Same as MIDI 1.0, use struct usb_ms_header_descriptor */
+
+/* 5.3.2 Class-Specific MIDI Streaming Data Endpoint Descriptor */
+struct usb_ms20_endpoint_descriptor {
+       __u8  bLength;                  /* 4+n */
+       __u8  bDescriptorType;          /* USB_DT_CS_ENDPOINT */
+       __u8  bDescriptorSubtype;       /* USB_MS_GENERAL_2_0 */
+       __u8  bNumGrpTrmBlock;          /* Number of Group Terminal Blocks: n */
+       __u8  baAssoGrpTrmBlkID[];      /* ID of the Group Terminal Blocks [n] */
+} __packed;
+
+#define USB_DT_MS20_ENDPOINT_SIZE(n)   (4 + (n))
+
+/* As above, but more useful for defining your own descriptors: */
+#define DECLARE_USB_MS20_ENDPOINT_DESCRIPTOR(n)                        \
+struct usb_ms20_endpoint_descriptor_##n {                      \
+       __u8  bLength;                                          \
+       __u8  bDescriptorType;                                  \
+       __u8  bDescriptorSubtype;                               \
+       __u8  bNumGrpTrmBlock;                                  \
+       __u8  baAssoGrpTrmBlkID[n];                             \
+} __packed
+
+/* 5.4.1 Class-Specific Group Terminal Block Header Descriptor */
+struct usb_ms20_gr_trm_block_header_descriptor {
+       __u8  bLength;                  /* 5 */
+       __u8  bDescriptorType;          /* USB_DT_CS_GR_TRM_BLOCK */
+       __u8  bDescriptorSubtype;       /* USB_MS_GR_TRM_BLOCK_HEADER */
+       __u16 wTotalLength;             /* Total number of bytes */
+} __packed;
+
+/* 5.4.2.1 Group Terminal Block Descriptor */
+struct usb_ms20_gr_trm_block_descriptor {
+       __u8  bLength;                  /* 13 */
+       __u8  bDescriptorType;          /* USB_DT_CS_GR_TRM_BLOCK */
+       __u8  bDescriptorSubtype;       /* USB_MS_GR_TRM_BLOCK */
+       __u8  bGrpTrmBlkID;             /* ID of this Group Terminal Block */
+       __u8  bGrpTrmBlkType;           /* Group Terminal Block Type */
+       __u8  nGroupTrm;                /* The first member Group Terminal in this block */
+       __u8  nNumGroupTrm;             /* Number of member Group Terminals spanned */
+       __u8  iBlockItem;               /* String ID of Block item */
+       __u8  bMIDIProtocol;            /* Default MIDI protocol */
+       __u16 wMaxInputBandwidth;       /* Max input bandwidth capability in 4kB/s */
+       __u16 wMaxOutputBandwidth;      /* Max output bandwidth capability in 4kB/s */
+} __packed;
+
+#endif /* __LINUX_USB_MIDI_V2_H */