emux_seq.c

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/*
 *  Midi Sequencer interface routines.
 *
 *  Copyright (C) 1999 Steve Ratcliffe
 *  Copyright (c) 1999-2000 Takashi Iwai <[email protected]>
 *
 *   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 2 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.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 */

#include "emux_voice.h"
#include <linux/slab.h>
#include <linux/module.h>

/* Prototypes for static functions */
static void free_port(void *private);
static void snd_emux_init_port(struct snd_emux_port *p);
static int snd_emux_use(void *private_data, struct snd_seq_port_subscribe *info);
static int snd_emux_unuse(void *private_data, struct snd_seq_port_subscribe *info);

/*
 * MIDI emulation operators
 */
static struct snd_midi_op emux_ops = {
    snd_emux_note_on,
    snd_emux_note_off,
    snd_emux_key_press,
    snd_emux_terminate_note,
    snd_emux_control,
    snd_emux_nrpn,
    snd_emux_sysex,
};


/*
 * number of MIDI channels
 */
#define MIDI_CHANNELS       16

/*
 * type flags for MIDI sequencer port
 */
#define DEFAULT_MIDI_TYPE   (SNDRV_SEQ_PORT_TYPE_MIDI_GENERIC |\
                 SNDRV_SEQ_PORT_TYPE_MIDI_GM |\
                 SNDRV_SEQ_PORT_TYPE_MIDI_GS |\
                 SNDRV_SEQ_PORT_TYPE_MIDI_XG |\
                 SNDRV_SEQ_PORT_TYPE_HARDWARE |\
                 SNDRV_SEQ_PORT_TYPE_SYNTHESIZER)

/*
 * Initialise the EMUX Synth by creating a client and registering
 * a series of ports.
 * Each of the ports will contain the 16 midi channels.  Applications
 * can connect to these ports to play midi data.
 */
int
snd_emux_init_seq(struct snd_emux *emu, struct snd_card *card, int index)
{
    int  i;
    struct snd_seq_port_callback pinfo;
    char tmpname[64];

    emu->client = snd_seq_create_kernel_client(card, index,
                           "%s WaveTable", emu->name);
    if (emu->client < 0) {
        snd_printk(KERN_ERR "can't create client\n");
        return -ENODEV;
    }

    if (emu->num_ports < 0) {
        snd_printk(KERN_WARNING "seqports must be greater than zero\n");
        emu->num_ports = 1;
    } else if (emu->num_ports >= SNDRV_EMUX_MAX_PORTS) {
        snd_printk(KERN_WARNING "too many ports."
               "limited max. ports %d\n", SNDRV_EMUX_MAX_PORTS);
        emu->num_ports = SNDRV_EMUX_MAX_PORTS;
    }

    memset(&pinfo, 0, sizeof(pinfo));
    pinfo.owner = THIS_MODULE;
    pinfo.use = snd_emux_use;
    pinfo.unuse = snd_emux_unuse;
    pinfo.event_input = snd_emux_event_input;

    for (i = 0; i < emu->num_ports; i++) {
        struct snd_emux_port *p;

        sprintf(tmpname, "%s Port %d", emu->name, i);
        p = snd_emux_create_port(emu, tmpname, MIDI_CHANNELS,
                     0, &pinfo);
        if (p == NULL) {
            snd_printk(KERN_ERR "can't create port\n");
            return -ENOMEM;
        }

        p->port_mode =  SNDRV_EMUX_PORT_MODE_MIDI;
        snd_emux_init_port(p);
        emu->ports[i] = p->chset.port;
        emu->portptrs[i] = p;
    }

    return 0;
}


/*
 * Detach from the ports that were set up for this synthesizer and
 * destroy the kernel client.
 */
void
snd_emux_detach_seq(struct snd_emux *emu)
{
    if (emu->voices)
        snd_emux_terminate_all(emu);
        
    mutex_lock(&emu->register_mutex);
    if (emu->client >= 0) {
        snd_seq_delete_kernel_client(emu->client);
        emu->client = -1;
    }
    mutex_unlock(&emu->register_mutex);
}


/*
 * create a sequencer port and channel_set
 */

struct snd_emux_port *
snd_emux_create_port(struct snd_emux *emu, char *name,
             int max_channels, int oss_port,
             struct snd_seq_port_callback *callback)
{
    struct snd_emux_port *p;
    int i, type, cap;

    /* Allocate structures for this channel */
    if ((p = kzalloc(sizeof(*p), GFP_KERNEL)) == NULL) {
        snd_printk(KERN_ERR "no memory\n");
        return NULL;
    }
    p->chset.channels = kcalloc(max_channels, sizeof(struct snd_midi_channel), GFP_KERNEL);
    if (p->chset.channels == NULL) {
        snd_printk(KERN_ERR "no memory\n");
        kfree(p);
        return NULL;
    }
    for (i = 0; i < max_channels; i++)
        p->chset.channels[i].number = i;
    p->chset.private_data = p;
    p->chset.max_channels = max_channels;
    p->emu = emu;
    p->chset.client = emu->client;
#ifdef SNDRV_EMUX_USE_RAW_EFFECT
    snd_emux_create_effect(p);
#endif
    callback->private_free = free_port;
    callback->private_data = p;

    cap = SNDRV_SEQ_PORT_CAP_WRITE;
    if (oss_port) {
        type = SNDRV_SEQ_PORT_TYPE_SPECIFIC;
    } else {
        type = DEFAULT_MIDI_TYPE;
        cap |= SNDRV_SEQ_PORT_CAP_SUBS_WRITE;
    }

    p->chset.port = snd_seq_event_port_attach(emu->client, callback,
                          cap, type, max_channels,
                          emu->max_voices, name);

    return p;
}


/*
 * release memory block for port
 */
static void
free_port(void *private_data)
{
    struct snd_emux_port *p;

    p = private_data;
    if (p) {
#ifdef SNDRV_EMUX_USE_RAW_EFFECT
        snd_emux_delete_effect(p);
#endif
        kfree(p->chset.channels);
        kfree(p);
    }
}


#define DEFAULT_DRUM_FLAGS  (1<<9)

/*
 * initialize the port specific parameters
 */
static void
snd_emux_init_port(struct snd_emux_port *p)
{
    p->drum_flags = DEFAULT_DRUM_FLAGS;
    p->volume_atten = 0;

    snd_emux_reset_port(p);
}


/*
 * reset port
 */
void
snd_emux_reset_port(struct snd_emux_port *port)
{
    int i;

    /* stop all sounds */
    snd_emux_sounds_off_all(port);

    snd_midi_channel_set_clear(&port->chset);

#ifdef SNDRV_EMUX_USE_RAW_EFFECT
    snd_emux_clear_effect(port);
#endif

    /* set port specific control parameters */
    port->ctrls[EMUX_MD_DEF_BANK] = 0;
    port->ctrls[EMUX_MD_DEF_DRUM] = 0;
    port->ctrls[EMUX_MD_REALTIME_PAN] = 1;

    for (i = 0; i < port->chset.max_channels; i++) {
        struct snd_midi_channel *chan = port->chset.channels + i;
        chan->drum_channel = ((port->drum_flags >> i) & 1) ? 1 : 0;
    }
}


/*
 * input sequencer event
 */
int
snd_emux_event_input(struct snd_seq_event *ev, int direct, void *private_data,
             int atomic, int hop)
{
    struct snd_emux_port *port;

    port = private_data;
    if (snd_BUG_ON(!port || !ev))
        return -EINVAL;

    snd_midi_process_event(&emux_ops, ev, &port->chset);

    return 0;
}


/*
 * increment usage count
 */
int
snd_emux_inc_count(struct snd_emux *emu)
{
    emu->used++;
    if (!try_module_get(emu->ops.owner))
        goto __error;
    if (!try_module_get(emu->card->module)) {
        module_put(emu->ops.owner);
          __error:
        emu->used--;
        return 0;
    }
    return 1;
}


/*
 * decrease usage count
 */
void
snd_emux_dec_count(struct snd_emux *emu)
{
    module_put(emu->card->module);
    emu->used--;
    if (emu->used <= 0)
        snd_emux_terminate_all(emu);
    module_put(emu->ops.owner);
}


/*
 * Routine that is called upon a first use of a particular port
 */
static int
snd_emux_use(void *private_data, struct snd_seq_port_subscribe *info)
{
    struct snd_emux_port *p;
    struct snd_emux *emu;

    p = private_data;
    if (snd_BUG_ON(!p))
        return -EINVAL;
    emu = p->emu;
    if (snd_BUG_ON(!emu))
        return -EINVAL;

    mutex_lock(&emu->register_mutex);
    snd_emux_init_port(p);
    snd_emux_inc_count(emu);
    mutex_unlock(&emu->register_mutex);
    return 0;
}

/*
 * Routine that is called upon the last unuse() of a particular port.
 */
static int
snd_emux_unuse(void *private_data, struct snd_seq_port_subscribe *info)
{
    struct snd_emux_port *p;
    struct snd_emux *emu;

    p = private_data;
    if (snd_BUG_ON(!p))
        return -EINVAL;
    emu = p->emu;
    if (snd_BUG_ON(!emu))
        return -EINVAL;

    mutex_lock(&emu->register_mutex);
    snd_emux_sounds_off_all(p);
    snd_emux_dec_count(emu);
    mutex_unlock(&emu->register_mutex);
    return 0;
}


/*
 * attach virtual rawmidi devices
 */
int snd_emux_init_virmidi(struct snd_emux *emu, struct snd_card *card)
{
    int i;

    emu->vmidi = NULL;
    if (emu->midi_ports <= 0)
        return 0;

    emu->vmidi = kcalloc(emu->midi_ports, sizeof(struct snd_rawmidi *), GFP_KERNEL);
    if (emu->vmidi == NULL)
        return -ENOMEM;

    for (i = 0; i < emu->midi_ports; i++) {
        struct snd_rawmidi *rmidi;
        struct snd_virmidi_dev *rdev;
        if (snd_virmidi_new(card, emu->midi_devidx + i, &rmidi) < 0)
            goto __error;
        rdev = rmidi->private_data;
        sprintf(rmidi->name, "%s Synth MIDI", emu->name);
        rdev->seq_mode = SNDRV_VIRMIDI_SEQ_ATTACH;
        rdev->client = emu->client;
        rdev->port = emu->ports[i];
        if (snd_device_register(card, rmidi) < 0) {
            snd_device_free(card, rmidi);
            goto __error;
        }
        emu->vmidi[i] = rmidi;
        /* snd_printk(KERN_DEBUG "virmidi %d ok\n", i); */
    }
    return 0;

__error:
    /* snd_printk(KERN_DEBUG "error init..\n"); */
    snd_emux_delete_virmidi(emu);
    return -ENOMEM;
}

int snd_emux_delete_virmidi(struct snd_emux *emu)
{
    int i;

    if (emu->vmidi == NULL)
        return 0;

    for (i = 0; i < emu->midi_ports; i++) {
        if (emu->vmidi[i])
            snd_device_free(emu->card, emu->vmidi[i]);
    }
    kfree(emu->vmidi);
    emu->vmidi = NULL;
    return 0;
}