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|
/*
* Generic MIDI synth driver for ALSA sequencer
* Copyright (c) 1998 by Frank van de Pol <fvdpol@coil.demon.nl>
* Jaroslav Kysela <perex@suse.cz>
*
* 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
*
*/
/*
Possible options for midisynth module:
- automatic opening of midi ports on first received event or subscription
(close will be performed when client leaves)
*/
#include <sound/driver.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/moduleparam.h>
#include <asm/semaphore.h>
#include <sound/core.h>
#include <sound/rawmidi.h>
#include <sound/seq_kernel.h>
#include <sound/seq_device.h>
#include <sound/seq_midi_event.h>
#include <sound/initval.h>
MODULE_AUTHOR("Frank van de Pol <fvdpol@coil.demon.nl>, Jaroslav Kysela <perex@suse.cz>");
MODULE_DESCRIPTION("Advanced Linux Sound Architecture sequencer MIDI synth.");
MODULE_LICENSE("GPL");
static int output_buffer_size = PAGE_SIZE;
module_param(output_buffer_size, int, 0644);
MODULE_PARM_DESC(output_buffer_size, "Output buffer size in bytes.");
static int input_buffer_size = PAGE_SIZE;
module_param(input_buffer_size, int, 0644);
MODULE_PARM_DESC(input_buffer_size, "Input buffer size in bytes.");
/* data for this midi synth driver */
typedef struct {
snd_card_t *card;
int device;
int subdevice;
snd_rawmidi_file_t input_rfile;
snd_rawmidi_file_t output_rfile;
int seq_client;
int seq_port;
snd_midi_event_t *parser;
} seq_midisynth_t;
typedef struct {
int seq_client;
int num_ports;
int ports_per_device[SNDRV_RAWMIDI_DEVICES];
seq_midisynth_t *ports[SNDRV_RAWMIDI_DEVICES];
} seq_midisynth_client_t;
static seq_midisynth_client_t *synths[SNDRV_CARDS];
static DECLARE_MUTEX(register_mutex);
/* handle rawmidi input event (MIDI v1.0 stream) */
static void snd_midi_input_event(snd_rawmidi_substream_t * substream)
{
snd_rawmidi_runtime_t *runtime;
seq_midisynth_t *msynth;
snd_seq_event_t ev;
char buf[16], *pbuf;
long res, count;
if (substream == NULL)
return;
runtime = substream->runtime;
msynth = (seq_midisynth_t *) runtime->private_data;
if (msynth == NULL)
return;
memset(&ev, 0, sizeof(ev));
while (runtime->avail > 0) {
res = snd_rawmidi_kernel_read(substream, buf, sizeof(buf));
if (res <= 0)
continue;
if (msynth->parser == NULL)
continue;
pbuf = buf;
while (res > 0) {
count = snd_midi_event_encode(msynth->parser, pbuf, res, &ev);
if (count < 0)
break;
pbuf += count;
res -= count;
if (ev.type != SNDRV_SEQ_EVENT_NONE) {
ev.source.port = msynth->seq_port;
ev.dest.client = SNDRV_SEQ_ADDRESS_SUBSCRIBERS;
snd_seq_kernel_client_dispatch(msynth->seq_client, &ev, 1, 0);
/* clear event and reset header */
memset(&ev, 0, sizeof(ev));
}
}
}
}
static int dump_midi(snd_rawmidi_substream_t *substream, const char *buf, int count)
{
snd_rawmidi_runtime_t *runtime;
int tmp;
snd_assert(substream != NULL || buf != NULL, return -EINVAL);
runtime = substream->runtime;
if ((tmp = runtime->avail) < count) {
snd_printd("warning, output event was lost (count = %i, available = %i)\n", count, tmp);
return -ENOMEM;
}
if (snd_rawmidi_kernel_write(substream, buf, count) < count)
return -EINVAL;
return 0;
}
static int event_process_midi(snd_seq_event_t * ev, int direct,
void *private_data, int atomic, int hop)
{
seq_midisynth_t *msynth = (seq_midisynth_t *) private_data;
unsigned char msg[10]; /* buffer for constructing midi messages */
snd_rawmidi_substream_t *substream;
int res;
snd_assert(msynth != NULL, return -EINVAL);
substream = msynth->output_rfile.output;
if (substream == NULL)
return -ENODEV;
if (ev->type == SNDRV_SEQ_EVENT_SYSEX) { /* special case, to save space */
if ((ev->flags & SNDRV_SEQ_EVENT_LENGTH_MASK) != SNDRV_SEQ_EVENT_LENGTH_VARIABLE) {
/* invalid event */
snd_printd("seq_midi: invalid sysex event flags = 0x%x\n", ev->flags);
return 0;
}
res = snd_seq_dump_var_event(ev, (snd_seq_dump_func_t)dump_midi, substream);
snd_midi_event_reset_decode(msynth->parser);
if (res < 0)
return res;
} else {
if (msynth->parser == NULL)
return -EIO;
res = snd_midi_event_decode(msynth->parser, msg, sizeof(msg), ev);
if (res < 0)
return res;
if ((res = dump_midi(substream, msg, res)) < 0) {
snd_midi_event_reset_decode(msynth->parser);
return res;
}
}
return 0;
}
static int snd_seq_midisynth_new(seq_midisynth_t *msynth,
snd_card_t *card,
int device,
int subdevice)
{
if (snd_midi_event_new(MAX_MIDI_EVENT_BUF, &msynth->parser) < 0)
return -ENOMEM;
msynth->card = card;
msynth->device = device;
msynth->subdevice = subdevice;
return 0;
}
/* open associated midi device for input */
static int midisynth_subscribe(void *private_data, snd_seq_port_subscribe_t *info)
{
int err;
seq_midisynth_t *msynth = (seq_midisynth_t *)private_data;
snd_rawmidi_runtime_t *runtime;
snd_rawmidi_params_t params;
/* open midi port */
if ((err = snd_rawmidi_kernel_open(msynth->card->number, msynth->device, msynth->subdevice, SNDRV_RAWMIDI_LFLG_INPUT, &msynth->input_rfile)) < 0) {
snd_printd("midi input open failed!!!\n");
return err;
}
runtime = msynth->input_rfile.input->runtime;
memset(¶ms, 0, sizeof(params));
params.avail_min = 1;
params.buffer_size = input_buffer_size;
if ((err = snd_rawmidi_input_params(msynth->input_rfile.input, ¶ms)) < 0) {
snd_rawmidi_kernel_release(&msynth->input_rfile);
return err;
}
snd_midi_event_reset_encode(msynth->parser);
runtime->event = snd_midi_input_event;
runtime->private_data = msynth;
snd_rawmidi_kernel_read(msynth->input_rfile.input, NULL, 0);
return 0;
}
/* close associated midi device for input */
static int midisynth_unsubscribe(void *private_data, snd_seq_port_subscribe_t *info)
{
int err;
seq_midisynth_t *msynth = (seq_midisynth_t *)private_data;
snd_assert(msynth->input_rfile.input != NULL, return -EINVAL);
err = snd_rawmidi_kernel_release(&msynth->input_rfile);
return err;
}
/* open associated midi device for output */
static int midisynth_use(void *private_data, snd_seq_port_subscribe_t *info)
{
int err;
seq_midisynth_t *msynth = (seq_midisynth_t *)private_data;
snd_rawmidi_params_t params;
/* open midi port */
if ((err = snd_rawmidi_kernel_open(msynth->card->number, msynth->device, msynth->subdevice, SNDRV_RAWMIDI_LFLG_OUTPUT, &msynth->output_rfile)) < 0) {
snd_printd("midi output open failed!!!\n");
return err;
}
memset(¶ms, 0, sizeof(params));
params.avail_min = 1;
params.buffer_size = output_buffer_size;
if ((err = snd_rawmidi_output_params(msynth->output_rfile.output, ¶ms)) < 0) {
snd_rawmidi_kernel_release(&msynth->output_rfile);
return err;
}
snd_midi_event_reset_decode(msynth->parser);
return 0;
}
/* close associated midi device for output */
static int midisynth_unuse(void *private_data, snd_seq_port_subscribe_t *info)
{
seq_midisynth_t *msynth = (seq_midisynth_t *)private_data;
unsigned char buf = 0xff; /* MIDI reset */
snd_assert(msynth->output_rfile.output != NULL, return -EINVAL);
/* sending single MIDI reset message to shut the device up */
snd_rawmidi_kernel_write(msynth->output_rfile.output, &buf, 1);
snd_rawmidi_drain_output(msynth->output_rfile.output);
return snd_rawmidi_kernel_release(&msynth->output_rfile);
}
/* delete given midi synth port */
static void snd_seq_midisynth_delete(seq_midisynth_t *msynth)
{
if (msynth == NULL)
return;
if (msynth->seq_client > 0) {
/* delete port */
snd_seq_event_port_detach(msynth->seq_client, msynth->seq_port);
}
if (msynth->parser)
snd_midi_event_free(msynth->parser);
}
/* set our client name */
static int set_client_name(seq_midisynth_client_t *client, snd_card_t *card,
snd_rawmidi_info_t *rmidi)
{
snd_seq_client_info_t cinfo;
const char *name;
memset(&cinfo, 0, sizeof(cinfo));
cinfo.client = client->seq_client;
cinfo.type = KERNEL_CLIENT;
name = rmidi->name[0] ? (const char *)rmidi->name : "External MIDI";
strlcpy(cinfo.name, name, sizeof(cinfo.name));
return snd_seq_kernel_client_ctl(client->seq_client, SNDRV_SEQ_IOCTL_SET_CLIENT_INFO, &cinfo);
}
/* register new midi synth port */
static int
snd_seq_midisynth_register_port(snd_seq_device_t *dev)
{
seq_midisynth_client_t *client;
seq_midisynth_t *msynth, *ms;
snd_seq_port_info_t *port;
snd_rawmidi_info_t *info;
int newclient = 0;
unsigned int p, ports;
snd_seq_client_callback_t callbacks;
snd_seq_port_callback_t pcallbacks;
snd_card_t *card = dev->card;
int device = dev->device;
unsigned int input_count = 0, output_count = 0;
snd_assert(card != NULL && device >= 0 && device < SNDRV_RAWMIDI_DEVICES, return -EINVAL);
info = kmalloc(sizeof(*info), GFP_KERNEL);
if (! info)
return -ENOMEM;
info->device = device;
info->stream = SNDRV_RAWMIDI_STREAM_OUTPUT;
info->subdevice = 0;
if (snd_rawmidi_info_select(card, info) >= 0)
output_count = info->subdevices_count;
info->stream = SNDRV_RAWMIDI_STREAM_INPUT;
if (snd_rawmidi_info_select(card, info) >= 0) {
input_count = info->subdevices_count;
}
ports = output_count;
if (ports < input_count)
ports = input_count;
if (ports == 0) {
kfree(info);
return -ENODEV;
}
if (ports > (256 / SNDRV_RAWMIDI_DEVICES))
ports = 256 / SNDRV_RAWMIDI_DEVICES;
down(®ister_mutex);
client = synths[card->number];
if (client == NULL) {
newclient = 1;
client = kcalloc(1, sizeof(*client), GFP_KERNEL);
if (client == NULL) {
up(®ister_mutex);
kfree(info);
return -ENOMEM;
}
memset(&callbacks, 0, sizeof(callbacks));
callbacks.private_data = client;
callbacks.allow_input = callbacks.allow_output = 1;
client->seq_client = snd_seq_create_kernel_client(card, 0, &callbacks);
if (client->seq_client < 0) {
kfree(client);
up(®ister_mutex);
kfree(info);
return -ENOMEM;
}
set_client_name(client, card, info);
} else if (device == 0)
set_client_name(client, card, info); /* use the first device's name */
msynth = kcalloc(ports, sizeof(seq_midisynth_t), GFP_KERNEL);
port = kmalloc(sizeof(*port), GFP_KERNEL);
if (msynth == NULL || port == NULL)
goto __nomem;
for (p = 0; p < ports; p++) {
ms = &msynth[p];
if (snd_seq_midisynth_new(ms, card, device, p) < 0)
goto __nomem;
/* declare port */
memset(port, 0, sizeof(*port));
port->addr.client = client->seq_client;
port->addr.port = device * (256 / SNDRV_RAWMIDI_DEVICES) + p;
port->flags = SNDRV_SEQ_PORT_FLG_GIVEN_PORT;
memset(info, 0, sizeof(*info));
info->device = device;
if (p < output_count)
info->stream = SNDRV_RAWMIDI_STREAM_OUTPUT;
else
info->stream = SNDRV_RAWMIDI_STREAM_INPUT;
info->subdevice = p;
if (snd_rawmidi_info_select(card, info) >= 0)
strcpy(port->name, info->subname);
if (! port->name[0]) {
if (info->name[0]) {
if (ports > 1)
snprintf(port->name, sizeof(port->name), "%s-%d", info->name, p);
else
snprintf(port->name, sizeof(port->name), "%s", info->name);
} else {
/* last resort */
if (ports > 1)
sprintf(port->name, "MIDI %d-%d-%d", card->number, device, p);
else
sprintf(port->name, "MIDI %d-%d", card->number, device);
}
}
if ((info->flags & SNDRV_RAWMIDI_INFO_OUTPUT) && p < output_count)
port->capability |= SNDRV_SEQ_PORT_CAP_WRITE | SNDRV_SEQ_PORT_CAP_SYNC_WRITE | SNDRV_SEQ_PORT_CAP_SUBS_WRITE;
if ((info->flags & SNDRV_RAWMIDI_INFO_INPUT) && p < input_count)
port->capability |= SNDRV_SEQ_PORT_CAP_READ | SNDRV_SEQ_PORT_CAP_SYNC_READ | SNDRV_SEQ_PORT_CAP_SUBS_READ;
if ((port->capability & (SNDRV_SEQ_PORT_CAP_WRITE|SNDRV_SEQ_PORT_CAP_READ)) == (SNDRV_SEQ_PORT_CAP_WRITE|SNDRV_SEQ_PORT_CAP_READ) &&
info->flags & SNDRV_RAWMIDI_INFO_DUPLEX)
port->capability |= SNDRV_SEQ_PORT_CAP_DUPLEX;
port->type = SNDRV_SEQ_PORT_TYPE_MIDI_GENERIC;
port->midi_channels = 16;
memset(&pcallbacks, 0, sizeof(pcallbacks));
pcallbacks.owner = THIS_MODULE;
pcallbacks.private_data = ms;
pcallbacks.subscribe = midisynth_subscribe;
pcallbacks.unsubscribe = midisynth_unsubscribe;
pcallbacks.use = midisynth_use;
pcallbacks.unuse = midisynth_unuse;
pcallbacks.event_input = event_process_midi;
port->kernel = &pcallbacks;
if (snd_seq_kernel_client_ctl(client->seq_client, SNDRV_SEQ_IOCTL_CREATE_PORT, port)<0)
goto __nomem;
ms->seq_client = client->seq_client;
ms->seq_port = port->addr.port;
}
client->ports_per_device[device] = ports;
client->ports[device] = msynth;
client->num_ports++;
if (newclient)
synths[card->number] = client;
up(®ister_mutex);
return 0; /* success */
__nomem:
if (msynth != NULL) {
for (p = 0; p < ports; p++)
snd_seq_midisynth_delete(&msynth[p]);
kfree(msynth);
}
if (newclient) {
snd_seq_delete_kernel_client(client->seq_client);
kfree(client);
}
kfree(info);
kfree(port);
up(®ister_mutex);
return -ENOMEM;
}
/* release midi synth port */
static int
snd_seq_midisynth_unregister_port(snd_seq_device_t *dev)
{
seq_midisynth_client_t *client;
seq_midisynth_t *msynth;
snd_card_t *card = dev->card;
int device = dev->device, p, ports;
down(®ister_mutex);
client = synths[card->number];
if (client == NULL || client->ports[device] == NULL) {
up(®ister_mutex);
return -ENODEV;
}
ports = client->ports_per_device[device];
client->ports_per_device[device] = 0;
msynth = client->ports[device];
client->ports[device] = NULL;
snd_runtime_check(msynth != NULL || ports <= 0, goto __skip);
for (p = 0; p < ports; p++)
snd_seq_midisynth_delete(&msynth[p]);
kfree(msynth);
__skip:
client->num_ports--;
if (client->num_ports <= 0) {
snd_seq_delete_kernel_client(client->seq_client);
synths[card->number] = NULL;
kfree(client);
}
up(®ister_mutex);
return 0;
}
static int __init alsa_seq_midi_init(void)
{
static snd_seq_dev_ops_t ops = {
snd_seq_midisynth_register_port,
snd_seq_midisynth_unregister_port,
};
memset(&synths, 0, sizeof(synths));
snd_seq_autoload_lock();
snd_seq_device_register_driver(SNDRV_SEQ_DEV_ID_MIDISYNTH, &ops, 0);
snd_seq_autoload_unlock();
return 0;
}
static void __exit alsa_seq_midi_exit(void)
{
snd_seq_device_unregister_driver(SNDRV_SEQ_DEV_ID_MIDISYNTH);
}
module_init(alsa_seq_midi_init)
module_exit(alsa_seq_midi_exit)
|