linux/sound/core/ump_convert.c

// 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)
{ … }

static u16 downscale_32_to_14bit(u32 src)
{ … }

static u8 downscale_16_to_7bit(u16 src)
{ … }

static u16 upscale_7_to_16bit(u8 src)
{ … }

static u32 upscale_7_to_32bit(u8 src)
{ … }

static u32 upscale_14_to_32bit(u16 src)
{ … }

/*
 * 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)
{ … }

/* 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)
{ … }

/* 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)
{ … }

/* 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)
{ … }

/**
 * 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)
{ … }
EXPORT_SYMBOL_GPL(…);

/*
 * 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)
{ … }

/* convert to a UMP System message */
static int cvt_legacy_system_to_ump(struct ump_cvt_to_ump *cvt,
				    unsigned char group, u32 *data)
{ … }

static void reset_rpn(struct ump_cvt_to_ump_bank *cc)
{ … }

static int fill_rpn(struct ump_cvt_to_ump_bank *cc,
		    union snd_ump_midi2_msg *midi2,
		    bool flush)
{ … }

/* 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)
{ … }

static int do_convert_to_ump(struct ump_cvt_to_ump *cvt, unsigned char group,
			     unsigned int protocol, unsigned char c, u32 *data)
{ … }

/**
 * 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)
{ … }
EXPORT_SYMBOL_GPL(…);