source: buchla-emu/emu/mid.c@ 77d8df8

/*
 *  Copyright (C) 2017 The Contributors
 *
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or (at
 *  your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful, but
 *  WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 *  General Public License for more details.
 *
 *  A copy of the GNU General Public License can be found in the file
 *  "gpl.txt" in the top directory of this repository.
 */

#include <all.h>
#include <rtmidi/rtmidi_c.h>

#define ver(...) _ver(mid_verbose, 0, __VA_ARGS__)
#define ver2(...) _ver(mid_verbose, 1, __VA_ARGS__)
#define ver3(...) _ver(mid_verbose, 2, __VA_ARGS__)

#define REG_IER_ISR 0
#define REG_CFR_SR  1
#define REG_CDR_TBR 2
#define REG_TDR_RDR 3

#define BUF_SZ 256

typedef struct {
        int32_t buf_hd;
        int32_t buf_tl;
        uint8_t buf[BUF_SZ];
        bool irq_r;
        bool irq_t;
        bool rdr_ok;
        uint8_t rdr;
} state_t;

static state_t state[] = {
        { .buf_hd = 0, .buf_tl = 0, .irq_r = false, .irq_t = false, .rdr_ok = false, .rdr = 0x00 },
        { .buf_hd = 0, .buf_tl = 0, .irq_r = false, .irq_t = false, .rdr_ok = false, .rdr = 0x00 }
};

int32_t mid_verbose = 0;

struct RtMidiWrapper* mid_in;

static void xmit(int32_t un)
{
        int32_t i = state[un].buf_tl;
        ver2("mid xmit %d %d", i, state[un].buf_hd);

        if (i >= state[un].buf_hd) {
                return;
        }

        uint8_t byte = state[un].buf[i % BUF_SZ];
        ver2("mid xmit 0x%02x", byte);

        state[un].rdr = byte;
        state[un].rdr_ok = true;
        state[un].irq_r = true;

        state[un].buf_tl = i + 1;

        if (state[un].buf_tl >= BUF_SZ) {
                state[un].buf_hd -= BUF_SZ;
                state[un].buf_tl -= BUF_SZ;
                ver2("mid adj %d %d", state[un].buf_tl, state[un].buf_hd);
        }
}

static void out_lk(int32_t un, uint8_t c)
{
        int32_t i = state[un].buf_hd;
        ver2("mid out %d %d 0x%02x", state[un].buf_tl, i, c);

        if (i >= state[un].buf_tl + BUF_SZ) {
                err("midi port %d losing data", un);
                return;
        }

        state[un].buf[i % BUF_SZ] = c;
        state[un].buf_hd = i + 1;

        if (!state[un].irq_r && !state[un].rdr_ok) {
                xmit(un);
        }
}

static void out(int32_t un, uint8_t c)
{
        if (SDL_LockMutex(cpu_mutex) < 0) {
                fail("SDL_LockMutex() failed: %s", SDL_GetError());
        }

        out_lk(un, c);

        if (SDL_UnlockMutex(cpu_mutex) < 0) {
                fail("SDL_UnlockMutex() failed: %s", SDL_GetError());
        }
}

static void mid_callback(double timeStamp, const unsigned char* message, size_t size, void *userData) {
        (void) size;
        (void) userData;

        ver2("Timestamp %f\n", timeStamp);

        for (uint8_t i = 0; i < sizeof(message); i++) {
                ver2("Message %i %u", i, (uint8_t) message[i]);
                out(0, message[i]);
        }
}

void mid_init(void)
{
        ver("mid init");

        mid_in = rtmidi_in_create_default();
        ver2("%p", mid_in->ptr);
        // check if null

        uint32_t portcount = rtmidi_get_port_count(mid_in);
        if (portcount == 0) {
                mid_in = NULL;
                ver2("No MIDI ports\n");
                return;
        }

        if (mid_port > portcount) {
                mid_in = NULL;
                ver2("Selected MIDI port larger than number of midi ports");
                return;
        }

        rtmidi_open_port(mid_in, mid_port, rtmidi_get_port_name(mid_in, mid_port));

        if(mid_in->ok == 0) {
                fail("Failed to open MIDI port");
        }

        ver2("Using MIDI port %u", mid_port);

        rtmidi_in_set_callback(mid_in, mid_callback, mid_in->data);

        if(mid_in->ok == 0) {
                fail("Failed to set MIDI Callback");
        }
}

void mid_quit(void)
{
        if(mid_in) {
                rtmidi_close_port(mid_in);
                rtmidi_in_free(mid_in);
        }

        ver("mid quit");
}

bool mid_exec(void)
{
        ver3("mid exec");
        return state[0].irq_r || state[0].irq_t || state[1].irq_r || state[1].irq_t;
}

uint32_t mid_read(uint32_t off, int32_t sz)
{
        ver2("mid rd %u:%d", off, sz * 8);

        if (sz != 1 || off > 7) {
                fail("invalid mid rd %u:%d", off, sz * 8);
        }

        int32_t rg = (int32_t)(off % 4);
        int32_t un = (int32_t)(off / 4);

        uint32_t rv;

        switch (rg) {
        case REG_IER_ISR:
                rv = (uint32_t)(0xc0 | (state[un].rdr_ok ? 0x01 : 0x00));
                state[un].irq_r = false;
                state[un].irq_t = false;
                ver2("ISR[%d] 0x%02x", un, rv);
                break;

        case REG_TDR_RDR:
                rv = state[un].rdr;
                state[un].rdr_ok = false;
                ver2("RDR[%d] 0x%02x", un, rv);
                break;

        default:
                rv = 0x00;
                break;
        }

        if (!state[un].irq_r && !state[un].rdr_ok) {
                xmit(un);
        }

        return rv;
}

void mid_write(uint32_t off, int32_t sz, uint32_t val)
{
        ver2("mid wr %u:%d 0x%0*x", off, sz * 8, sz * 2, val);

        if (sz != 1 || off > 7) {
                fail("invalid mid wr %u:%d", off, sz * 8);
        }

        int32_t rg = (int32_t)(off % 4);
        int32_t un = (int32_t)(off / 4);

        switch (rg) {
        case REG_CFR_SR:
                ver2("CFR[%d] 0x%02x", un, val);

                if (un == 1) {
                        fdd_set_side((int32_t)val & 0x01);
                }
                else {
                        fdd_set_sel((int32_t)val & 0x01);
                }

                break;

        default:
                break;
        }
}

void mid_list(void) {
        mid_in = rtmidi_in_create_default();

        uint32_t portcount = rtmidi_get_port_count(mid_in);

        if (portcount == 0) {
                mid_in = NULL;
                ver2("no MIDI ports\n");
                return;
        }

        fprintf(stdout, "the following MIDI ports are available:\n");

        for (uint32_t i = 0; i < portcount; i++) {
                fprintf(stdout, "port %d: %s\n", i, rtmidi_get_port_name(mid_in, i));
        }

        rtmidi_in_free(mid_in);
}