// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Helpers for UMP <-> MIDI 1.0 byte stream conversion
*/
#include <linux/module.h>
#include <linux/export.h>
#include <sound/core.h>
#include <sound/asound.h>
#include <sound/ump.h>
#include <sound/ump_convert.h>
/*
* Upgrade / downgrade value bits
*/
static u8 downscale_32_to_7bit(u32 src)
{
return src >> 25;
}
static u16 downscale_32_to_14bit(u32 src)
{
return src >> 18;
}
static u8 downscale_16_to_7bit(u16 src)
{
return src >> 9;
}
static u16 upscale_7_to_16bit(u8 src)
{
u16 val, repeat;
val = (u16)src << 9;
if (src <= 0x40)
return val;
repeat = src & 0x3f;
return val | (repeat << 3) | (repeat >> 3);
}
static u32 upscale_7_to_32bit(u8 src)
{
u32 val, repeat;
val = src << 25;
if (src <= 0x40)
return val;
repeat = src & 0x3f;
return val | (repeat << 19) | (repeat << 13) |
(repeat << 7) | (repeat << 1) | (repeat >> 5);
}
static u32 upscale_14_to_32bit(u16 src)
{
u32 val, repeat;
val = src << 18;
if (src <= 0x2000)
return val;
repeat = src & 0x1fff;
return val | (repeat << 5) | (repeat >> 8);
}
/*
* UMP -> MIDI 1 byte stream conversion
*/
/* convert a UMP System message to MIDI 1.0 byte stream */
static int cvt_ump_system_to_legacy(u32 data, unsigned char *buf)
{
buf[0] = ump_message_status_channel(data);
switch (ump_message_status_code(data)) {
case UMP_SYSTEM_STATUS_MIDI_TIME_CODE:
case UMP_SYSTEM_STATUS_SONG_SELECT:
buf[1] = (data >> 8) & 0x7f;
return 2;
case UMP_SYSTEM_STATUS_SONG_POSITION:
buf[1] = (data >> 8) & 0x7f;
buf[2] = data & 0x7f;
return 3;
default:
return 1;
}
}
/* convert a UMP MIDI 1.0 Channel Voice message to MIDI 1.0 byte stream */
static int cvt_ump_midi1_to_legacy(u32 data, unsigned char *buf)
{
buf[0] = ump_message_status_channel(data);
buf[1] = (data >> 8) & 0xff;
switch (ump_message_status_code(data)) {
case UMP_MSG_STATUS_PROGRAM:
case UMP_MSG_STATUS_CHANNEL_PRESSURE:
return 2;
default:
buf[2] = data & 0xff;
return 3;
}
}
/* convert a UMP MIDI 2.0 Channel Voice message to MIDI 1.0 byte stream */
static int cvt_ump_midi2_to_legacy(const union snd_ump_midi2_msg *midi2,
unsigned char *buf)
{
unsigned char status = midi2->note.status;
unsigned char channel = midi2->note.channel;
u16 v;
buf[0] = (status << 4) | channel;
switch (status) {
case UMP_MSG_STATUS_NOTE_OFF:
case UMP_MSG_STATUS_NOTE_ON:
buf[1] = midi2->note.note;
buf[2] = downscale_16_to_7bit(midi2->note.velocity);
if (status == UMP_MSG_STATUS_NOTE_ON && !buf[2])
buf[2] = 1;
return 3;
case UMP_MSG_STATUS_POLY_PRESSURE:
buf[1] = midi2->paf.note;
buf[2] = downscale_32_to_7bit(midi2->paf.data);
return 3;
case UMP_MSG_STATUS_CC:
buf[1] = midi2->cc.index;
buf[2] = downscale_32_to_7bit(midi2->cc.data);
return 3;
case UMP_MSG_STATUS_CHANNEL_PRESSURE:
buf[1] = downscale_32_to_7bit(midi2->caf.data);
return 2;
case UMP_MSG_STATUS_PROGRAM:
if (midi2->pg.bank_valid) {
buf[0] = channel | (UMP_MSG_STATUS_CC << 4);
buf[1] = UMP_CC_BANK_SELECT;
buf[2] = midi2->pg.bank_msb;
buf[3] = channel | (UMP_MSG_STATUS_CC << 4);
buf[4] = UMP_CC_BANK_SELECT_LSB;
buf[5] = midi2->pg.bank_lsb;
buf[6] = channel | (UMP_MSG_STATUS_PROGRAM << 4);
buf[7] = midi2->pg.program;
return 8;
}
buf[1] = midi2->pg.program;
return 2;
case UMP_MSG_STATUS_PITCH_BEND:
v = downscale_32_to_14bit(midi2->pb.data);
buf[1] = v & 0x7f;
buf[2] = v >> 7;
return 3;
case UMP_MSG_STATUS_RPN:
case UMP_MSG_STATUS_NRPN:
buf[0] = channel | (UMP_MSG_STATUS_CC << 4);
buf[1] = status == UMP_MSG_STATUS_RPN ? UMP_CC_RPN_MSB : UMP_CC_NRPN_MSB;
buf[2] = midi2->rpn.bank;
buf[3] = buf[0];
buf[4] = status == UMP_MSG_STATUS_RPN ? UMP_CC_RPN_LSB : UMP_CC_NRPN_LSB;
buf[5] = midi2->rpn.index;
buf[6] = buf[0];
buf[7] = UMP_CC_DATA;
v = downscale_32_to_14bit(midi2->rpn.data);
buf[8] = v >> 7;
buf[9] = buf[0];
buf[10] = UMP_CC_DATA_LSB;
buf[11] = v & 0x7f;
return 12;
default:
return 0;
}
}
/* convert a UMP 7-bit SysEx message to MIDI 1.0 byte stream */
static int cvt_ump_sysex7_to_legacy(const u32 *data, unsigned char *buf)
{
unsigned char status;
unsigned char bytes;
int size, offset;
status = ump_sysex_message_status(*data);
if (status > UMP_SYSEX_STATUS_END)
return 0; // unsupported, skip
bytes = ump_sysex_message_length(*data);
if (bytes > 6)
return 0; // skip
size = 0;
if (status == UMP_SYSEX_STATUS_SINGLE ||
status == UMP_SYSEX_STATUS_START) {
buf[0] = UMP_MIDI1_MSG_SYSEX_START;
size = 1;
}
offset = 8;
for (; bytes; bytes--, size++) {
buf[size] = (*data >> offset) & 0x7f;
if (!offset) {
offset = 24;
data++;
} else {
offset -= 8;
}
}
if (status == UMP_SYSEX_STATUS_SINGLE ||
status == UMP_SYSEX_STATUS_END)
buf[size++] = UMP_MIDI1_MSG_SYSEX_END;
return size;
}
/**
* snd_ump_convert_from_ump - convert from UMP to legacy MIDI
* @data: UMP packet
* @buf: buffer to store legacy MIDI data
* @group_ret: pointer to store the target group
*
* Convert from a UMP packet @data to MIDI 1.0 bytes at @buf.
* The target group is stored at @group_ret.
*
* The function returns the number of bytes of MIDI 1.0 stream.
*/
int snd_ump_convert_from_ump(const u32 *data,
unsigned char *buf,
unsigned char *group_ret)
{
*group_ret = ump_message_group(*data);
switch (ump_message_type(*data)) {
case UMP_MSG_TYPE_SYSTEM:
return cvt_ump_system_to_legacy(*data, buf);
case UMP_MSG_TYPE_MIDI1_CHANNEL_VOICE:
return cvt_ump_midi1_to_legacy(*data, buf);
case UMP_MSG_TYPE_MIDI2_CHANNEL_VOICE:
return cvt_ump_midi2_to_legacy((const union snd_ump_midi2_msg *)data,
buf);
case UMP_MSG_TYPE_DATA:
return cvt_ump_sysex7_to_legacy(data, buf);
}
return 0;
}
EXPORT_SYMBOL_GPL(snd_ump_convert_from_ump);
/*
* MIDI 1 byte stream -> UMP conversion
*/
/* convert MIDI 1.0 SysEx to a UMP packet */
static int cvt_legacy_sysex_to_ump(struct ump_cvt_to_ump *cvt,
unsigned char group, u32 *data, bool finish)
{
unsigned char status;
bool start = cvt->in_sysex == 1;
int i, offset;
if (start && finish)
status = UMP_SYSEX_STATUS_SINGLE;
else if (start)
status = UMP_SYSEX_STATUS_START;
else if (finish)
status = UMP_SYSEX_STATUS_END;
else
status = UMP_SYSEX_STATUS_CONTINUE;
*data = ump_compose(UMP_MSG_TYPE_DATA, group, status, cvt->len);
offset = 8;
for (i = 0; i < cvt->len; i++) {
*data |= cvt->buf[i] << offset;
if (!offset) {
offset = 24;
data++;
} else
offset -= 8;
}
cvt->len = 0;
if (finish)
cvt->in_sysex = 0;
else
cvt->in_sysex++;
return 8;
}
/* convert to a UMP System message */
static int cvt_legacy_system_to_ump(struct ump_cvt_to_ump *cvt,
unsigned char group, u32 *data)
{
data[0] = ump_compose(UMP_MSG_TYPE_SYSTEM, group, 0, cvt->buf[0]);
if (cvt->cmd_bytes > 1)
data[0] |= cvt->buf[1] << 8;
if (cvt->cmd_bytes > 2)
data[0] |= cvt->buf[2];
return 4;
}
static void reset_rpn(struct ump_cvt_to_ump_bank *cc)
{
cc->rpn_set = 0;
cc->nrpn_set = 0;
cc->cc_rpn_msb = cc->cc_rpn_lsb = 0;
cc->cc_data_msb = cc->cc_data_lsb = 0;
cc->cc_data_msb_set = cc->cc_data_lsb_set = 0;
}
static int fill_rpn(struct ump_cvt_to_ump_bank *cc,
union snd_ump_midi2_msg *midi2,
bool flush)
{
if (!(cc->cc_data_lsb_set || cc->cc_data_msb_set))
return 0; // skip
/* when not flushing, wait for complete data set */
if (!flush && (!cc->cc_data_lsb_set || !cc->cc_data_msb_set))
return 0; // skip
if (cc->rpn_set) {
midi2->rpn.status = UMP_MSG_STATUS_RPN;
midi2->rpn.bank = cc->cc_rpn_msb;
midi2->rpn.index = cc->cc_rpn_lsb;
} else if (cc->nrpn_set) {
midi2->rpn.status = UMP_MSG_STATUS_NRPN;
midi2->rpn.bank = cc->cc_nrpn_msb;
midi2->rpn.index = cc->cc_nrpn_lsb;
} else {
return 0; // skip
}
midi2->rpn.data = upscale_14_to_32bit((cc->cc_data_msb << 7) |
cc->cc_data_lsb);
reset_rpn(cc);
return 1;
}
/* convert to a MIDI 1.0 Channel Voice message */
static int cvt_legacy_cmd_to_ump(struct ump_cvt_to_ump *cvt,
unsigned char group,
unsigned int protocol,
u32 *data, unsigned char bytes)
{
const unsigned char *buf = cvt->buf;
struct ump_cvt_to_ump_bank *cc;
union snd_ump_midi2_msg *midi2 = (union snd_ump_midi2_msg *)data;
unsigned char status, channel;
int ret;
BUILD_BUG_ON(sizeof(union snd_ump_midi1_msg) != 4);
BUILD_BUG_ON(sizeof(union snd_ump_midi2_msg) != 8);
/* for MIDI 1.0 UMP, it's easy, just pack it into UMP */
if (protocol & SNDRV_UMP_EP_INFO_PROTO_MIDI1) {
data[0] = ump_compose(UMP_MSG_TYPE_MIDI1_CHANNEL_VOICE,
group, 0, buf[0]);
data[0] |= buf[1] << 8;
if (bytes > 2)
data[0] |= buf[2];
return 4;
}
status = *buf >> 4;
channel = *buf & 0x0f;
cc = &cvt->bank[channel];
/* special handling: treat note-on with 0 velocity as note-off */
if (status == UMP_MSG_STATUS_NOTE_ON && !buf[2])
status = UMP_MSG_STATUS_NOTE_OFF;
/* initialize the packet */
data[0] = ump_compose(UMP_MSG_TYPE_MIDI2_CHANNEL_VOICE,
group, status, channel);
data[1] = 0;
switch (status) {
case UMP_MSG_STATUS_NOTE_ON:
case UMP_MSG_STATUS_NOTE_OFF:
midi2->note.note = buf[1];
midi2->note.velocity = upscale_7_to_16bit(buf[2]);
break;
case UMP_MSG_STATUS_POLY_PRESSURE:
midi2->paf.note = buf[1];
midi2->paf.data = upscale_7_to_32bit(buf[2]);
break;
case UMP_MSG_STATUS_CC:
switch (buf[1]) {
case UMP_CC_RPN_MSB:
ret = fill_rpn(cc, midi2, true);
cc->rpn_set = 1;
cc->cc_rpn_msb = buf[2];
if (cc->cc_rpn_msb == 0x7f && cc->cc_rpn_lsb == 0x7f)
reset_rpn(cc);
return ret;
case UMP_CC_RPN_LSB:
ret = fill_rpn(cc, midi2, true);
cc->rpn_set = 1;
cc->cc_rpn_lsb = buf[2];
if (cc->cc_rpn_msb == 0x7f && cc->cc_rpn_lsb == 0x7f)
reset_rpn(cc);
return ret;
case UMP_CC_NRPN_MSB:
ret = fill_rpn(cc, midi2, true);
cc->nrpn_set = 1;
cc->cc_nrpn_msb = buf[2];
return ret;
case UMP_CC_NRPN_LSB:
ret = fill_rpn(cc, midi2, true);
cc->nrpn_set = 1;
cc->cc_nrpn_lsb = buf[2];
return ret;
case UMP_CC_DATA:
cc->cc_data_msb_set = 1;
cc->cc_data_msb = buf[2];
return fill_rpn(cc, midi2, false);
case UMP_CC_BANK_SELECT:
cc->bank_set = 1;
cc->cc_bank_msb = buf[2];
return 0; // skip
case UMP_CC_BANK_SELECT_LSB:
cc->bank_set = 1;
cc->cc_bank_lsb = buf[2];
return 0; // skip
case UMP_CC_DATA_LSB:
cc->cc_data_lsb_set = 1;
cc->cc_data_lsb = buf[2];
return fill_rpn(cc, midi2, false);
default:
midi2->cc.index = buf[1];
midi2->cc.data = upscale_7_to_32bit(buf[2]);
break;
}
break;
case UMP_MSG_STATUS_PROGRAM:
midi2->pg.program = buf[1];
if (cc->bank_set) {
midi2->pg.bank_valid = 1;
midi2->pg.bank_msb = cc->cc_bank_msb;
midi2->pg.bank_lsb = cc->cc_bank_lsb;
cc->bank_set = 0;
}
break;
case UMP_MSG_STATUS_CHANNEL_PRESSURE:
midi2->caf.data = upscale_7_to_32bit(buf[1]);
break;
case UMP_MSG_STATUS_PITCH_BEND:
midi2->pb.data = upscale_14_to_32bit(buf[1] | (buf[2] << 7));
break;
default:
return 0;
}
return 8;
}
static int do_convert_to_ump(struct ump_cvt_to_ump *cvt, unsigned char group,
unsigned int protocol, unsigned char c, u32 *data)
{
/* bytes for 0x80-0xf0 */
static unsigned char cmd_bytes[8] = {
3, 3, 3, 3, 2, 2, 3, 0
};
/* bytes for 0xf0-0xff */
static unsigned char system_bytes[16] = {
0, 2, 3, 2, 0, 0, 1, 0, 1, 1, 1, 1, 0, 0, 1, 1
};
unsigned char bytes;
if (c == UMP_MIDI1_MSG_SYSEX_START) {
cvt->in_sysex = 1;
cvt->len = 0;
return 0;
}
if (c == UMP_MIDI1_MSG_SYSEX_END) {
if (!cvt->in_sysex)
return 0; /* skip */
return cvt_legacy_sysex_to_ump(cvt, group, data, true);
}
if ((c & 0xf0) == UMP_MIDI1_MSG_REALTIME) {
bytes = system_bytes[c & 0x0f];
if (!bytes)
return 0; /* skip */
if (bytes == 1) {
data[0] = ump_compose(UMP_MSG_TYPE_SYSTEM, group, 0, c);
return 4;
}
cvt->buf[0] = c;
cvt->len = 1;
cvt->cmd_bytes = bytes;
cvt->in_sysex = 0; /* abort SysEx */
return 0;
}
if (c & 0x80) {
bytes = cmd_bytes[(c >> 4) & 7];
cvt->buf[0] = c;
cvt->len = 1;
cvt->cmd_bytes = bytes;
cvt->in_sysex = 0; /* abort SysEx */
return 0;
}
if (cvt->in_sysex) {
cvt->buf[cvt->len++] = c;
if (cvt->len == 6)
return cvt_legacy_sysex_to_ump(cvt, group, data, false);
return 0;
}
if (!cvt->len)
return 0;
cvt->buf[cvt->len++] = c;
if (cvt->len < cvt->cmd_bytes)
return 0;
cvt->len = 1;
if ((cvt->buf[0] & 0xf0) == UMP_MIDI1_MSG_REALTIME)
return cvt_legacy_system_to_ump(cvt, group, data);
return cvt_legacy_cmd_to_ump(cvt, group, protocol, data, cvt->cmd_bytes);
}
/**
* snd_ump_convert_to_ump - convert legacy MIDI byte to UMP packet
* @cvt: converter context
* @group: target UMP group
* @protocol: target UMP protocol
* @c: MIDI 1.0 byte data
*
* Feed a MIDI 1.0 byte @c and convert to a UMP packet if completed.
* The result is stored in the buffer in @cvt.
*/
void snd_ump_convert_to_ump(struct ump_cvt_to_ump *cvt, unsigned char group,
unsigned int protocol, unsigned char c)
{
cvt->ump_bytes = do_convert_to_ump(cvt, group, protocol, c, cvt->ump);
}
EXPORT_SYMBOL_GPL(snd_ump_convert_to_ump);
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