maschine mikro -> midi translator

midi_mikro.c

/**
 * william light <wrl@illest.net> wrote this in 2012
 *
 * released under creative commons CC0
 * http://creativecommons.org/publicdomain/zero/1.0/
 */

#include <sys/stat.h>
#include <stdlib.h>
#include <fcntl.h>
#include <stdio.h>
#include <errno.h>
#include <stdint.h>
#include <unistd.h>
#include <math.h>
#include <string.h>

#include <linux/hidraw.h>

#include <alsa/asoundlib.h>
#include <alsa/seq.h>

#include "mikro.h"


#define DIE(...) \
	do {\
		fprintf(stderr, __VA_ARGS__);\
		exit(1);\
	} while (0);


static uint8_t pad_note_map[16] = {
	60, 61, 62, 63,
	56, 57, 58, 59,
	52, 53, 54, 55,
	48, 49, 50, 51
};

#define MIDI_NOTE_FOR_PAD(X) (pad_note_map[X])

static snd_seq_t *handle;
static int seq_port;
static snd_seq_event_t seq_ev;

static int process_pads(uint8_t *data, uint16_t *pads)
{
	uint16_t new;
	int i, changed, vel;

	changed = 0;

	for (i = 0; i < 16; i++) {
		new = ((data[0] << 4) | (data[1] & 0x0F));
		data += 2;

		if (pads[i] == new)
			continue;

		vel = lrintf((new / 4095.f) * 127.f);
		vel = 127;

		if (!pads[i]) {
			/* we already know the new value is different, otherwise we'd
			   have hit the above "continue" */

			snd_seq_ev_set_noteon(&seq_ev, 1, MIDI_NOTE_FOR_PAD(i), vel);
		} else {
			if (new)
				snd_seq_ev_set_keypress(&seq_ev, 1, MIDI_NOTE_FOR_PAD(i), vel);
			else
				snd_seq_ev_set_noteoff(&seq_ev, 1, MIDI_NOTE_FOR_PAD(i), vel);
		}

		snd_seq_event_output(handle, &seq_ev);
		snd_seq_drain_output(handle);

		pads[i] = new;
		changed = 1;
	}

	return changed;
}

uint8_t light_buf[61] = {
	[0] = 0x80,
	[1 ... 60] = 1,
	[29 ... 36] = 0
};

static void output_lights(int fd)
{
	write(fd, light_buf, sizeof(light_buf));
}

static int pad_to_light_map[16] = {
	52, 51, 50, 49,
	48, 47, 46, 45,
	28, 27, 26, 25,
	24, 23, 22, 21
};

uint8_t buttons[5] = {[0 ... 3] = 0, [4] = 16};

static void button_dispatch(uint8_t *data)
{
	int i, off, code, diff;

	for (i = 0; i < 4; i++) {
		diff = data[i] ^ buttons[i];

		while (!!diff) {
			off = ffs(diff);
			code = mikro_bitfield_button_map[i][8 - off];

			if (data[i] & (1 << (off - 1)))
				printf(" [+] %s\n", maschine_buttons_to_string[code]);
			else
				printf(" [ ] %s\n", maschine_buttons_to_string[code]);

			diff >>= off;
		}

		buttons[i] = data[i];
	}

	if (buttons[4] > 15) {
		buttons[4] = data[4];
		return;
	}

	if (buttons[4] == data[4])
		return;

	if (((buttons[4] + 1) & 0xF) == data[4])
		printf(" [>] encoder\n");
	else
		printf(" [<] encoder\n");

	buttons[4] = data[4];
}

static void read_from_dev(int fd)
{
	uint8_t buf[128], src, *data;
	uint16_t pads[16] = {[0 ... 15] = 4095};
	ssize_t nbytes;
	int i;

	printf("let's do it\n\n");

	do {
		if ((nbytes = read(fd, &buf, sizeof(buf))) < 0) {
			perror("read");
			break;
		}

		src = buf[0];
		data = &buf[1];

		switch (src) {
		case 32:
			/* pads */
			if (!process_pads(data, pads))
				continue;

			for (i = 0; i < 16; i++)
				light_buf[pad_to_light_map[i]] = (33 - ((!!pads[i]) * 2)) & 0x1F;

			fflush(stdout);
			break;

		case 1:
			button_dispatch(data);

			break;

		default:
			printf(" [?] %3ld bytes from %d\n", nbytes, src);
		}

		output_lights(fd);
	} while (1);
}

static snd_seq_t *open_seq_client()
{
	snd_seq_t *handle;

	if (snd_seq_open(&handle, "default", SND_SEQ_OPEN_DUPLEX, 0) < 0)
		return NULL;

	snd_seq_set_client_name(handle, "Maschine Mikro Translator");
	return handle;
}

static int get_seq_port(snd_seq_t *handle, const char *name)
{
	return snd_seq_create_simple_port(
		handle, name, SND_SEQ_PORT_CAP_READ | SND_SEQ_PORT_CAP_SUBS_READ,
		SND_SEQ_PORT_TYPE_MIDI_GENERIC);
}

static void close_seq_client(snd_seq_t *handle)
{
	snd_seq_close(handle);
}

int main(int argc, char **argv)
{
	int fd;

	if (argc < 2)
		DIE("need device\n");

	if ((fd = open(argv[1], O_RDWR | O_EXCL)) < 0) {
		perror("open");
		return EXIT_FAILURE;
	}

	if (!(handle = open_seq_client()))
		DIE("couldn't open sequencer client\n");

	seq_port = get_seq_port(handle, "Maschine MIDI Out");

	snd_seq_ev_set_direct(&seq_ev);
	snd_seq_ev_set_source(&seq_ev, seq_port);
	snd_seq_ev_set_subs(&seq_ev);

	output_lights(fd);
	read_from_dev(fd);

	close_seq_client(handle);
	close(fd);

	return 0;
}

mikro.h

/**
 * william light <wrl@illest.net> wrote this in 2012
 *
 * released under creative commons CC0
 * http://creativecommons.org/publicdomain/zero/1.0/
 */

#include <stdint.h>

#define PACKED __attribute__((packed))

typedef unsigned int uint_t;

typedef enum {
	MASCHINE_BUTTON_DOWN,
	MASCHINE_BUTTON_UP,

	MASCHINE_ENCODER_TURN
} maschine_event_type_t;

typedef enum {
	MASCHINE_BTN_RESTART,
	MASCHINE_BTN_STEP_LEFT,
	MASCHINE_BTN_STEP_RIGHT,
	MASCHINE_BTN_GRID,
	MASCHINE_BTN_PLAY,
	MASCHINE_BTN_REC,
	MASCHINE_BTN_ERASE,
	MASCHINE_BTN_SHIFT,

	MASCHINE_BTN_BROWSE,
	MASCHINE_BTN_SAMPLING,
	MASCHINE_BTN_GROUP,
	MASCHINE_BTN_NOTE_REPEAT,
	MASCHINE_BTN_ENCODER,

	MASCHINE_BTN_F1,
	MASCHINE_BTN_F2,
	MASCHINE_BTN_F3,
	MASCHINE_BTN_MAIN,
	MASCHINE_BTN_NAV,
	MASCHINE_BTN_NAV_LEFT,
	MASCHINE_BTN_NAV_RIGHT,
	MASCHINE_BTN_ENTER,

	MASCHINE_BTN_SCENE,
	MASCHINE_BTN_PATTERN,
	MASCHINE_BTN_PAD_MODE,
	MASCHINE_BTN_VIEW,
	MASCHINE_BTN_DUPLICATE,
	MASCHINE_BTN_SELECT,
	MASCHINE_BTN_SOLO,
	MASCHINE_BTN_MUTE
} maschine_buttons_t;

const char *maschine_buttons_to_string[] = {
	[MASCHINE_BTN_RESTART] = "MASCHINE_BTN_RESTART",
	[MASCHINE_BTN_STEP_LEFT] = "MASCHINE_BTN_STEP_LEFT",
	[MASCHINE_BTN_STEP_RIGHT] = "MASCHINE_BTN_STEP_RIGHT",
	[MASCHINE_BTN_GRID] = "MASCHINE_BTN_GRID",
	[MASCHINE_BTN_PLAY] = "MASCHINE_BTN_PLAY",
	[MASCHINE_BTN_REC] = "MASCHINE_BTN_REC",
	[MASCHINE_BTN_ERASE] = "MASCHINE_BTN_ERASE",
	[MASCHINE_BTN_SHIFT] = "MASCHINE_BTN_SHIFT",

	[MASCHINE_BTN_BROWSE] = "MASCHINE_BTN_BROWSE",
	[MASCHINE_BTN_SAMPLING] = "MASCHINE_BTN_SAMPLING",
	[MASCHINE_BTN_GROUP] = "MASCHINE_BTN_GROUP",
	[MASCHINE_BTN_NOTE_REPEAT] = "MASCHINE_BTN_NOTE_REPEAT",
	[MASCHINE_BTN_ENCODER] = "MASCHINE_BTN_ENCODER",

	[MASCHINE_BTN_F1] = "MASCHINE_BTN_F1",
	[MASCHINE_BTN_F2] = "MASCHINE_BTN_F2",
	[MASCHINE_BTN_F3] = "MASCHINE_BTN_F3",
	[MASCHINE_BTN_MAIN] = "MASCHINE_BTN_MAIN",
	[MASCHINE_BTN_NAV] = "MASCHINE_BTN_NAV",
	[MASCHINE_BTN_NAV_LEFT] = "MASCHINE_BTN_NAV_LEFT",
	[MASCHINE_BTN_NAV_RIGHT] = "MASCHINE_BTN_NAV_RIGHT",
	[MASCHINE_BTN_ENTER] = "MASCHINE_BTN_ENTER",

	[MASCHINE_BTN_SCENE] = "MASCHINE_BTN_SCENE",
	[MASCHINE_BTN_PATTERN] = "MASCHINE_BTN_PATTERN",
	[MASCHINE_BTN_PAD_MODE] = "MASCHINE_BTN_PAD_MODE",
	[MASCHINE_BTN_VIEW] = "MASCHINE_BTN_VIEW",
	[MASCHINE_BTN_DUPLICATE] = "MASCHINE_BTN_DUPLICATE",
	[MASCHINE_BTN_SELECT] = "MASCHINE_BTN_SELECT",
	[MASCHINE_BTN_SOLO] = "MASCHINE_BTN_SOLO",
	[MASCHINE_BTN_MUTE] = "MASCHINE_BTN_MUTE"
};

struct mikro_button_report {
	uint_t restart:1;
	uint_t step_left:1;
	uint_t step_right:1;
	uint_t grid:1;
	uint_t play:1;
	uint_t rec:1;
	uint_t erase:1;
	uint_t shift:1;

	uint_t browse:1;
	uint_t sampling:1;
	uint_t group:1;
	uint_t note_repeat:1;
	uint_t encoder_press:1;
	uint_t unused:3;

	uint_t f1:1;
	uint_t f2:1;
	uint_t f3:1;
	uint_t main:1;
	uint_t nav:1;
	uint_t nav_left:1;
	uint_t nav_right:1;
	uint_t enter:1;

	uint_t scene:1;
	uint_t pattern:1;
	uint_t pad_mode:1;
	uint_t view:1;
	uint_t duplicate:1;
	uint_t select:1;
	uint_t solo:1;
	uint_t mute:1;

	uint8_t encoder;
} PACKED;

int mikro_bitfield_button_map[4][8] = {
	{
		MASCHINE_BTN_RESTART,
		MASCHINE_BTN_STEP_LEFT,
		MASCHINE_BTN_STEP_RIGHT,
		MASCHINE_BTN_GRID,
		MASCHINE_BTN_PLAY,
		MASCHINE_BTN_REC,
		MASCHINE_BTN_ERASE,
		MASCHINE_BTN_SHIFT
	},

	{
		MASCHINE_BTN_BROWSE,
		MASCHINE_BTN_SAMPLING,
		MASCHINE_BTN_GROUP,
		MASCHINE_BTN_NOTE_REPEAT,
		MASCHINE_BTN_ENCODER,
		0,
		0,
		0
	},

	{
		MASCHINE_BTN_F1,
		MASCHINE_BTN_F2,
		MASCHINE_BTN_F3,
		MASCHINE_BTN_MAIN,
		MASCHINE_BTN_NAV,
		MASCHINE_BTN_NAV_LEFT,
		MASCHINE_BTN_NAV_RIGHT,
		MASCHINE_BTN_ENTER
	},

	{
		MASCHINE_BTN_SCENE,
		MASCHINE_BTN_PATTERN,
		MASCHINE_BTN_PAD_MODE,
		MASCHINE_BTN_VIEW,
		MASCHINE_BTN_DUPLICATE,
		MASCHINE_BTN_SELECT,
		MASCHINE_BTN_SOLO,
		MASCHINE_BTN_MUTE
	}
};