diff options
Diffstat (limited to 'sound/core/seq/seq_midi.c')
| -rw-r--r-- | sound/core/seq/seq_midi.c | 468 |
1 files changed, 468 insertions, 0 deletions
diff --git a/sound/core/seq/seq_midi.c b/sound/core/seq/seq_midi.c new file mode 100644 index 000000000..9e0dabd3c --- /dev/null +++ b/sound/core/seq/seq_midi.c @@ -0,0 +1,468 @@ +/* + * 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; + + 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) { + if (!snd_midi_event_encode_byte(msynth->parser, + *pbuf++, &ev)) + continue; + 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); 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