seq_oss_init.c

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/*
 * OSS compatible sequencer driver
 *
 * open/close and reset interface
 *
 * Copyright (C) 1998-1999 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 "seq_oss_device.h"
#include "seq_oss_synth.h"
#include "seq_oss_midi.h"
#include "seq_oss_writeq.h"
#include "seq_oss_readq.h"
#include "seq_oss_timer.h"
#include "seq_oss_event.h"
#include <linux/init.h>
#include <linux/export.h>
#include <linux/moduleparam.h>
#include <linux/slab.h>

/*
 * common variables
 */
static int maxqlen = SNDRV_SEQ_OSS_MAX_QLEN;
module_param(maxqlen, int, 0444);
MODULE_PARM_DESC(maxqlen, "maximum queue length");

static int system_client = -1; /* ALSA sequencer client number */
static int system_port = -1;

static int num_clients;
static struct seq_oss_devinfo *client_table[SNDRV_SEQ_OSS_MAX_CLIENTS];


/*
 * prototypes
 */
static int receive_announce(struct snd_seq_event *ev, int direct, void *private, int atomic, int hop);
static int translate_mode(struct file *file);
static int create_port(struct seq_oss_devinfo *dp);
static int delete_port(struct seq_oss_devinfo *dp);
static int alloc_seq_queue(struct seq_oss_devinfo *dp);
static int delete_seq_queue(int queue);
static void free_devinfo(void *private);

#define call_ctl(type,rec) snd_seq_kernel_client_ctl(system_client, type, rec)


/*
 * create sequencer client for OSS sequencer
 */
int __init
snd_seq_oss_create_client(void)
{
    int rc;
    struct snd_seq_port_info *port;
    struct snd_seq_port_callback port_callback;

    port = kmalloc(sizeof(*port), GFP_KERNEL);
    if (!port) {
        rc = -ENOMEM;
        goto __error;
    }

    /* create ALSA client */
    rc = snd_seq_create_kernel_client(NULL, SNDRV_SEQ_CLIENT_OSS,
                      "OSS sequencer");
    if (rc < 0)
        goto __error;

    system_client = rc;
    debug_printk(("new client = %d\n", rc));

    /* look up midi devices */
    snd_seq_oss_midi_lookup_ports(system_client);

    /* create annoucement receiver port */
    memset(port, 0, sizeof(*port));
    strcpy(port->name, "Receiver");
    port->addr.client = system_client;
    port->capability = SNDRV_SEQ_PORT_CAP_WRITE; /* receive only */
    port->type = 0;

    memset(&port_callback, 0, sizeof(port_callback));
    /* don't set port_callback.owner here. otherwise the module counter
     * is incremented and we can no longer release the module..
     */
    port_callback.event_input = receive_announce;
    port->kernel = &port_callback;
    
    call_ctl(SNDRV_SEQ_IOCTL_CREATE_PORT, port);
    if ((system_port = port->addr.port) >= 0) {
        struct snd_seq_port_subscribe subs;

        memset(&subs, 0, sizeof(subs));
        subs.sender.client = SNDRV_SEQ_CLIENT_SYSTEM;
        subs.sender.port = SNDRV_SEQ_PORT_SYSTEM_ANNOUNCE;
        subs.dest.client = system_client;
        subs.dest.port = system_port;
        call_ctl(SNDRV_SEQ_IOCTL_SUBSCRIBE_PORT, &subs);
    }
    rc = 0;

 __error:
    kfree(port);
    return rc;
}


/*
 * receive annoucement from system port, and check the midi device
 */
static int
receive_announce(struct snd_seq_event *ev, int direct, void *private, int atomic, int hop)
{
    struct snd_seq_port_info pinfo;

    if (atomic)
        return 0; /* it must not happen */

    switch (ev->type) {
    case SNDRV_SEQ_EVENT_PORT_START:
    case SNDRV_SEQ_EVENT_PORT_CHANGE:
        if (ev->data.addr.client == system_client)
            break; /* ignore myself */
        memset(&pinfo, 0, sizeof(pinfo));
        pinfo.addr = ev->data.addr;
        if (call_ctl(SNDRV_SEQ_IOCTL_GET_PORT_INFO, &pinfo) >= 0)
            snd_seq_oss_midi_check_new_port(&pinfo);
        break;

    case SNDRV_SEQ_EVENT_PORT_EXIT:
        if (ev->data.addr.client == system_client)
            break; /* ignore myself */
        snd_seq_oss_midi_check_exit_port(ev->data.addr.client,
                        ev->data.addr.port);
        break;
    }
    return 0;
}


/*
 * delete OSS sequencer client
 */
int
snd_seq_oss_delete_client(void)
{
    if (system_client >= 0)
        snd_seq_delete_kernel_client(system_client);

    snd_seq_oss_midi_clear_all();

    return 0;
}


/*
 * open sequencer device
 */
int
snd_seq_oss_open(struct file *file, int level)
{
    int i, rc;
    struct seq_oss_devinfo *dp;

    dp = kzalloc(sizeof(*dp), GFP_KERNEL);
    if (!dp) {
        snd_printk(KERN_ERR "can't malloc device info\n");
        return -ENOMEM;
    }
    debug_printk(("oss_open: dp = %p\n", dp));

    dp->cseq = system_client;
    dp->port = -1;
    dp->queue = -1;

    for (i = 0; i < SNDRV_SEQ_OSS_MAX_CLIENTS; i++) {
        if (client_table[i] == NULL)
            break;
    }

    dp->index = i;
    if (i >= SNDRV_SEQ_OSS_MAX_CLIENTS) {
        snd_printk(KERN_ERR "too many applications\n");
        rc = -ENOMEM;
        goto _error;
    }

    /* look up synth and midi devices */
    snd_seq_oss_synth_setup(dp);
    snd_seq_oss_midi_setup(dp);

    if (dp->synth_opened == 0 && dp->max_mididev == 0) {
        /* snd_printk(KERN_ERR "no device found\n"); */
        rc = -ENODEV;
        goto _error;
    }

    /* create port */
    debug_printk(("create new port\n"));
    rc = create_port(dp);
    if (rc < 0) {
        snd_printk(KERN_ERR "can't create port\n");
        goto _error;
    }

    /* allocate queue */
    debug_printk(("allocate queue\n"));
    rc = alloc_seq_queue(dp);
    if (rc < 0)
        goto _error;

    /* set address */
    dp->addr.client = dp->cseq;
    dp->addr.port = dp->port;
    /*dp->addr.queue = dp->queue;*/
    /*dp->addr.channel = 0;*/

    dp->seq_mode = level;

    /* set up file mode */
    dp->file_mode = translate_mode(file);

    /* initialize read queue */
    debug_printk(("initialize read queue\n"));
    if (is_read_mode(dp->file_mode)) {
        dp->readq = snd_seq_oss_readq_new(dp, maxqlen);
        if (!dp->readq) {
            rc = -ENOMEM;
            goto _error;
        }
    }

    /* initialize write queue */
    debug_printk(("initialize write queue\n"));
    if (is_write_mode(dp->file_mode)) {
        dp->writeq = snd_seq_oss_writeq_new(dp, maxqlen);
        if (!dp->writeq) {
            rc = -ENOMEM;
            goto _error;
        }
    }

    /* initialize timer */
    debug_printk(("initialize timer\n"));
    dp->timer = snd_seq_oss_timer_new(dp);
    if (!dp->timer) {
        snd_printk(KERN_ERR "can't alloc timer\n");
        rc = -ENOMEM;
        goto _error;
    }
    debug_printk(("timer initialized\n"));

    /* set private data pointer */
    file->private_data = dp;

    /* set up for mode2 */
    if (level == SNDRV_SEQ_OSS_MODE_MUSIC)
        snd_seq_oss_synth_setup_midi(dp);
    else if (is_read_mode(dp->file_mode))
        snd_seq_oss_midi_open_all(dp, SNDRV_SEQ_OSS_FILE_READ);

    client_table[dp->index] = dp;
    num_clients++;

    debug_printk(("open done\n"));
    return 0;

 _error:
    snd_seq_oss_synth_cleanup(dp);
    snd_seq_oss_midi_cleanup(dp);
    delete_seq_queue(dp->queue);
    delete_port(dp);

    return rc;
}

/*
 * translate file flags to private mode
 */
static int
translate_mode(struct file *file)
{
    int file_mode = 0;
    if ((file->f_flags & O_ACCMODE) != O_RDONLY)
        file_mode |= SNDRV_SEQ_OSS_FILE_WRITE;
    if ((file->f_flags & O_ACCMODE) != O_WRONLY)
        file_mode |= SNDRV_SEQ_OSS_FILE_READ;
    if (file->f_flags & O_NONBLOCK)
        file_mode |= SNDRV_SEQ_OSS_FILE_NONBLOCK;
    return file_mode;
}


/*
 * create sequencer port
 */
static int
create_port(struct seq_oss_devinfo *dp)
{
    int rc;
    struct snd_seq_port_info port;
    struct snd_seq_port_callback callback;

    memset(&port, 0, sizeof(port));
    port.addr.client = dp->cseq;
    sprintf(port.name, "Sequencer-%d", dp->index);
    port.capability = SNDRV_SEQ_PORT_CAP_READ|SNDRV_SEQ_PORT_CAP_WRITE; /* no subscription */
    port.type = SNDRV_SEQ_PORT_TYPE_SPECIFIC;
    port.midi_channels = 128;
    port.synth_voices = 128;

    memset(&callback, 0, sizeof(callback));
    callback.owner = THIS_MODULE;
    callback.private_data = dp;
    callback.event_input = snd_seq_oss_event_input;
    callback.private_free = free_devinfo;
    port.kernel = &callback;

    rc = call_ctl(SNDRV_SEQ_IOCTL_CREATE_PORT, &port);
    if (rc < 0)
        return rc;

    dp->port = port.addr.port;
    debug_printk(("new port = %d\n", port.addr.port));

    return 0;
}

/*
 * delete ALSA port
 */
static int
delete_port(struct seq_oss_devinfo *dp)
{
    if (dp->port < 0) {
        kfree(dp);
        return 0;
    }

    debug_printk(("delete_port %i\n", dp->port));
    return snd_seq_event_port_detach(dp->cseq, dp->port);
}

/*
 * allocate a queue
 */
static int
alloc_seq_queue(struct seq_oss_devinfo *dp)
{
    struct snd_seq_queue_info qinfo;
    int rc;

    memset(&qinfo, 0, sizeof(qinfo));
    qinfo.owner = system_client;
    qinfo.locked = 1;
    strcpy(qinfo.name, "OSS Sequencer Emulation");
    if ((rc = call_ctl(SNDRV_SEQ_IOCTL_CREATE_QUEUE, &qinfo)) < 0)
        return rc;
    dp->queue = qinfo.queue;
    return 0;
}

/*
 * release queue
 */
static int
delete_seq_queue(int queue)
{
    struct snd_seq_queue_info qinfo;
    int rc;

    if (queue < 0)
        return 0;
    memset(&qinfo, 0, sizeof(qinfo));
    qinfo.queue = queue;
    rc = call_ctl(SNDRV_SEQ_IOCTL_DELETE_QUEUE, &qinfo);
    if (rc < 0)
        printk(KERN_ERR "seq-oss: unable to delete queue %d (%d)\n", queue, rc);
    return rc;
}


/*
 * free device informations - private_free callback of port
 */
static void
free_devinfo(void *private)
{
    struct seq_oss_devinfo *dp = (struct seq_oss_devinfo *)private;

    if (dp->timer)
        snd_seq_oss_timer_delete(dp->timer);
        
    if (dp->writeq)
        snd_seq_oss_writeq_delete(dp->writeq);

    if (dp->readq)
        snd_seq_oss_readq_delete(dp->readq);
    
    kfree(dp);
}


/*
 * close sequencer device
 */
void
snd_seq_oss_release(struct seq_oss_devinfo *dp)
{
    int queue;

    client_table[dp->index] = NULL;
    num_clients--;

    debug_printk(("resetting..\n"));
    snd_seq_oss_reset(dp);

    debug_printk(("cleaning up..\n"));
    snd_seq_oss_synth_cleanup(dp);
    snd_seq_oss_midi_cleanup(dp);

    /* clear slot */
    debug_printk(("releasing resource..\n"));
    queue = dp->queue;
    if (dp->port >= 0)
        delete_port(dp);
    delete_seq_queue(queue);

    debug_printk(("release done\n"));
}


/*
 * Wait until the queue is empty (if we don't have nonblock)
 */
void
snd_seq_oss_drain_write(struct seq_oss_devinfo *dp)
{
    if (! dp->timer->running)
        return;
    if (is_write_mode(dp->file_mode) && !is_nonblock_mode(dp->file_mode) &&
        dp->writeq) {
        debug_printk(("syncing..\n"));
        while (snd_seq_oss_writeq_sync(dp->writeq))
            ;
    }
}


/*
 * reset sequencer devices
 */
void
snd_seq_oss_reset(struct seq_oss_devinfo *dp)
{
    int i;

    /* reset all synth devices */
    for (i = 0; i < dp->max_synthdev; i++)
        snd_seq_oss_synth_reset(dp, i);

    /* reset all midi devices */
    if (dp->seq_mode != SNDRV_SEQ_OSS_MODE_MUSIC) {
        for (i = 0; i < dp->max_mididev; i++)
            snd_seq_oss_midi_reset(dp, i);
    }

    /* remove queues */
    if (dp->readq)
        snd_seq_oss_readq_clear(dp->readq);
    if (dp->writeq)
        snd_seq_oss_writeq_clear(dp->writeq);

    /* reset timer */
    snd_seq_oss_timer_stop(dp->timer);
}


#ifdef CONFIG_PROC_FS
/*
 * misc. functions for proc interface
 */
char *
enabled_str(int bool)
{
    return bool ? "enabled" : "disabled";
}

static char *
filemode_str(int val)
{
    static char *str[] = {
        "none", "read", "write", "read/write",
    };
    return str[val & SNDRV_SEQ_OSS_FILE_ACMODE];
}


/*
 * proc interface
 */
void
snd_seq_oss_system_info_read(struct snd_info_buffer *buf)
{
    int i;
    struct seq_oss_devinfo *dp;

    snd_iprintf(buf, "ALSA client number %d\n", system_client);
    snd_iprintf(buf, "ALSA receiver port %d\n", system_port);

    snd_iprintf(buf, "\nNumber of applications: %d\n", num_clients);
    for (i = 0; i < num_clients; i++) {
        snd_iprintf(buf, "\nApplication %d: ", i);
        if ((dp = client_table[i]) == NULL) {
            snd_iprintf(buf, "*empty*\n");
            continue;
        }
        snd_iprintf(buf, "port %d : queue %d\n", dp->port, dp->queue);
        snd_iprintf(buf, "  sequencer mode = %s : file open mode = %s\n",
                (dp->seq_mode ? "music" : "synth"),
                filemode_str(dp->file_mode));
        if (dp->seq_mode)
            snd_iprintf(buf, "  timer tempo = %d, timebase = %d\n",
                    dp->timer->oss_tempo, dp->timer->oss_timebase);
        snd_iprintf(buf, "  max queue length %d\n", maxqlen);
        if (is_read_mode(dp->file_mode) && dp->readq)
            snd_seq_oss_readq_info_read(dp->readq, buf);
    }
}
#endif /* CONFIG_PROC_FS */