diff options
Diffstat (limited to 'sound/core/seq/seq_midi.c')
| -rw-r--r-- | sound/core/seq/seq_midi.c | 489 | 
1 files changed, 489 insertions, 0 deletions
diff --git a/sound/core/seq/seq_midi.c b/sound/core/seq/seq_midi.c new file mode 100644 index 00000000000..18247db45db --- /dev/null +++ b/sound/core/seq/seq_midi.c @@ -0,0 +1,489 @@ +/* + *   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)  |