--- /dev/null
+/*
+ * Generic MIDI synth driver for ALSA sequencer
+ * Copyright (c) 1998 by Frank van de Pol <fvdpol@coil.demon.nl>
+ * Jaroslav Kysela <perex@perex.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 <linux/init.h>
+#include <linux/slab.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/module.h>
+#include <linux/mutex.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@perex.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 */
+struct seq_midisynth {
+ struct snd_card *card;
+ int device;
+ int subdevice;
+ struct snd_rawmidi_file input_rfile;
+ struct snd_rawmidi_file output_rfile;
+ int seq_client;
+ int seq_port;
+ struct snd_midi_event *parser;
+};
+
+struct seq_midisynth_client {
+ int seq_client;
+ int num_ports;
+ int ports_per_device[SNDRV_RAWMIDI_DEVICES];
+ struct seq_midisynth *ports[SNDRV_RAWMIDI_DEVICES];
+};
+
+static struct seq_midisynth_client *synths[SNDRV_CARDS];
+static DEFINE_MUTEX(register_mutex);
+
+/* handle rawmidi input event (MIDI v1.0 stream) */
+static void snd_midi_input_event(struct snd_rawmidi_substream *substream)
+{
+ struct snd_rawmidi_runtime *runtime;
+ struct seq_midisynth *msynth;
+ struct snd_seq_event ev;
+ char buf[16], *pbuf;
+ long res, count;
+
+ if (substream == NULL)
+ return;
+ runtime = substream->runtime;
+ msynth = 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(struct snd_rawmidi_substream *substream, const char *buf, int count)
+{
+ struct snd_rawmidi_runtime *runtime;
+ int tmp;
+
+ if (snd_BUG_ON(!substream || !buf))
+ return -EINVAL;
+ runtime = substream->runtime;
+ if ((tmp = runtime->avail) < count) {
+ if (printk_ratelimit())
+ pr_err("ALSA: seq_midi: MIDI output buffer overrun\n");
+ return -ENOMEM;
+ }
+ if (snd_rawmidi_kernel_write(substream, buf, count) < count)
+ return -EINVAL;
+ return 0;
+}
+
+static int event_process_midi(struct snd_seq_event *ev, int direct,
+ void *private_data, int atomic, int hop)
+{
+ struct seq_midisynth *msynth = private_data;
+ unsigned char msg[10]; /* buffer for constructing midi messages */
+ struct snd_rawmidi_substream *substream;
+ int len;
+
+ if (snd_BUG_ON(!msynth))
+ 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 */
+ pr_debug("ALSA: seq_midi: invalid sysex event flags = 0x%x\n", ev->flags);
+ return 0;
+ }
+ snd_seq_dump_var_event(ev, (snd_seq_dump_func_t)dump_midi, substream);
+ snd_midi_event_reset_decode(msynth->parser);
+ } else {
+ if (msynth->parser == NULL)
+ return -EIO;
+ len = snd_midi_event_decode(msynth->parser, msg, sizeof(msg), ev);
+ if (len < 0)
+ return 0;
+ if (dump_midi(substream, msg, len) < 0)
+ snd_midi_event_reset_decode(msynth->parser);
+ }
+ return 0;
+}
+
+
+static int snd_seq_midisynth_new(struct seq_midisynth *msynth,
+ struct snd_card *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, struct snd_seq_port_subscribe *info)
+{
+ int err;
+ struct seq_midisynth *msynth = private_data;
+ struct snd_rawmidi_runtime *runtime;
+ struct snd_rawmidi_params params;
+
+ /* open midi port */
+ if ((err = snd_rawmidi_kernel_open(msynth->card, msynth->device,
+ msynth->subdevice,
+ SNDRV_RAWMIDI_LFLG_INPUT,
+ &msynth->input_rfile)) < 0) {
+ pr_debug("ALSA: seq_midi: 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, struct snd_seq_port_subscribe *info)
+{
+ int err;
+ struct seq_midisynth *msynth = private_data;
+
+ if (snd_BUG_ON(!msynth->input_rfile.input))
+ 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, struct snd_seq_port_subscribe *info)
+{
+ int err;
+ struct seq_midisynth *msynth = private_data;
+ struct snd_rawmidi_params params;
+
+ /* open midi port */
+ if ((err = snd_rawmidi_kernel_open(msynth->card, msynth->device,
+ msynth->subdevice,
+ SNDRV_RAWMIDI_LFLG_OUTPUT,
+ &msynth->output_rfile)) < 0) {
+ pr_debug("ALSA: seq_midi: midi output open failed!!!\n");
+ return err;
+ }
+ memset(¶ms, 0, sizeof(params));
+ params.avail_min = 1;
+ params.buffer_size = output_buffer_size;
+ params.no_active_sensing = 1;
+ 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, struct snd_seq_port_subscribe *info)
+{
+ struct seq_midisynth *msynth = private_data;
+
+ if (snd_BUG_ON(!msynth->output_rfile.output))
+ return -EINVAL;
+ 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(struct seq_midisynth *msynth)
+{
+ if (msynth == NULL)
+ return;
+
+ if (msynth->seq_client > 0) {
+ /* delete port */
+ snd_seq_event_port_detach(msynth->seq_client, msynth->seq_port);
+ }
+
+ snd_midi_event_free(msynth->parser);
+}
+
+/* register new midi synth port */
+static int
+snd_seq_midisynth_probe(struct device *_dev)
+{
+ struct snd_seq_device *dev = to_seq_dev(_dev);
+ struct seq_midisynth_client *client;
+ struct seq_midisynth *msynth, *ms;
+ struct snd_seq_port_info *port;
+ struct snd_rawmidi_info *info;
+ struct snd_rawmidi *rmidi = dev->private_data;
+ int newclient = 0;
+ unsigned int p, ports;
+ struct snd_seq_port_callback pcallbacks;
+ struct snd_card *card = dev->card;
+ int device = dev->device;
+ unsigned int input_count = 0, output_count = 0;
+
+ if (snd_BUG_ON(!card || 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;
+
+ mutex_lock(®ister_mutex);
+ client = synths[card->number];
+ if (client == NULL) {
+ newclient = 1;
+ client = kzalloc(sizeof(*client), GFP_KERNEL);
+ if (client == NULL) {
+ mutex_unlock(®ister_mutex);
+ kfree(info);
+ return -ENOMEM;
+ }
+ client->seq_client =
+ snd_seq_create_kernel_client(
+ card, 0, "%s", card->shortname[0] ?
+ (const char *)card->shortname : "External MIDI");
+ if (client->seq_client < 0) {
+ kfree(client);
+ mutex_unlock(®ister_mutex);
+ kfree(info);
+ return -ENOMEM;
+ }
+ }
+
+ msynth = kcalloc(ports, sizeof(struct seq_midisynth), 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-%u", 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-%u", 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
+ | SNDRV_SEQ_PORT_TYPE_HARDWARE
+ | SNDRV_SEQ_PORT_TYPE_PORT;
+ 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 (rmidi->ops && rmidi->ops->get_port_info)
+ rmidi->ops->get_port_info(rmidi, p, port);
+ 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;
+ mutex_unlock(®ister_mutex);
+ kfree(info);
+ kfree(port);
+ 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);
+ mutex_unlock(®ister_mutex);
+ return -ENOMEM;
+}
+
+/* release midi synth port */
+static int
+snd_seq_midisynth_remove(struct device *_dev)
+{
+ struct snd_seq_device *dev = to_seq_dev(_dev);
+ struct seq_midisynth_client *client;
+ struct seq_midisynth *msynth;
+ struct snd_card *card = dev->card;
+ int device = dev->device, p, ports;
+
+ mutex_lock(®ister_mutex);
+ client = synths[card->number];
+ if (client == NULL || client->ports[device] == NULL) {
+ mutex_unlock(®ister_mutex);
+ return -ENODEV;
+ }
+ ports = client->ports_per_device[device];
+ client->ports_per_device[device] = 0;
+ msynth = client->ports[device];
+ client->ports[device] = NULL;
+ for (p = 0; p < ports; p++)
+ snd_seq_midisynth_delete(&msynth[p]);
+ kfree(msynth);
+ client->num_ports--;
+ if (client->num_ports <= 0) {
+ snd_seq_delete_kernel_client(client->seq_client);
+ synths[card->number] = NULL;
+ kfree(client);
+ }
+ mutex_unlock(®ister_mutex);
+ return 0;
+}
+
+static struct snd_seq_driver seq_midisynth_driver = {
+ .driver = {
+ .name = KBUILD_MODNAME,
+ .probe = snd_seq_midisynth_probe,
+ .remove = snd_seq_midisynth_remove,
+ },
+ .id = SNDRV_SEQ_DEV_ID_MIDISYNTH,
+ .argsize = 0,
+};
+
+module_snd_seq_driver(seq_midisynth_driver);
Code Review / kvmfornfv.git / blobdiff