aboutsummaryrefslogtreecommitdiffstats
path: root/sound/drivers/virmidi.c
blob: 33ef13a72e69aa9203cf6496e9a45c39bc135a2c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
/*
 *  Dummy soundcard for virtual rawmidi devices
 *
 *  Copyright (c) 2000 by Takashi Iwai <tiwai@suse.de>
 *
 *   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
 *
 */

/*
 * VIRTUAL RAW MIDI DEVICE CARDS
 *
 * This dummy card contains up to 4 virtual rawmidi devices.
 * They are not real rawmidi devices but just associated with sequencer
 * clients, so that any input/output sources can be connected as a raw
 * MIDI device arbitrary.
 * Also, multiple access is allowed to a single rawmidi device.
 *
 * Typical usage is like following:
 * - Load snd-virmidi module.
 *	# modprobe snd-virmidi index=2
 *   Then, sequencer clients 72:0 to 75:0 will be created, which are
 *   mapped from /dev/snd/midiC1D0 to /dev/snd/midiC1D3, respectively.
 *
 * - Connect input/output via aconnect.
 *	% aconnect 64:0 72:0	# keyboard input redirection 64:0 -> 72:0
 *	% aconnect 72:0 65:0	# output device redirection 72:0 -> 65:0
 *
 * - Run application using a midi device (eg. /dev/snd/midiC1D0)
 */

#include <linux/init.h>
#include <linux/wait.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/module.h>
#include <sound/core.h>
#include <sound/seq_kernel.h>
#include <sound/seq_virmidi.h>
#include <sound/initval.h>

/* hack: OSS defines midi_devs, so undefine it (versioned symbols) */
#undef midi_devs

MODULE_AUTHOR("Takashi Iwai <tiwai@suse.de>");
MODULE_DESCRIPTION("Dummy soundcard for virtual rawmidi devices");
MODULE_LICENSE("GPL");
MODULE_SUPPORTED_DEVICE("{{ALSA,Virtual rawmidi device}}");

#define MAX_MIDI_DEVICES	4

static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;	/* Index 0-MAX */
static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;	/* ID for this card */
static bool enable[SNDRV_CARDS] = {1, [1 ... (SNDRV_CARDS - 1)] = 0};
static int midi_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 4};

module_param_array(index, int, NULL, 0444);
MODULE_PARM_DESC(index, "Index value for virmidi soundcard.");
module_param_array(id, charp, NULL, 0444);
MODULE_PARM_DESC(id, "ID string for virmidi soundcard.");
module_param_array(enable, bool, NULL, 0444);
MODULE_PARM_DESC(enable, "Enable this soundcard.");
module_param_array(midi_devs, int, NULL, 0444);
MODULE_PARM_DESC(midi_devs, "MIDI devices # (1-4)");

struct snd_card_virmidi {
	struct snd_card *card;
	struct snd_rawmidi *midi[MAX_MIDI_DEVICES];
};

static struct platform_device *devices[SNDRV_CARDS];


static int snd_virmidi_probe(struct platform_device *devptr)
{
	struct snd_card *card;
	struct snd_card_virmidi *vmidi;
	int idx, err;
	int dev = devptr->id;

	err = snd_card_new(&devptr->dev, index[dev], id[dev], THIS_MODULE,
			   sizeof(struct snd_card_virmidi), &card);
	if (err < 0)
		return err;
	vmidi = card->private_data;
	vmidi->card = card;

	if (midi_devs[dev] > MAX_MIDI_DEVICES) {
		snd_printk(KERN_WARNING
			   "too much midi devices for virmidi %d: force to use %d\n",
			   dev, MAX_MIDI_DEVICES);
		midi_devs[dev] = MAX_MIDI_DEVICES;
	}
	for (idx = 0; idx < midi_devs[dev]; idx++) {
		struct snd_rawmidi *rmidi;
		struct snd_virmidi_dev *rdev;

		err = snd_virmidi_new(card, idx, &rmidi);
		if (err < 0)
			goto __nodev;
		rdev = rmidi->private_data;
		vmidi->midi[idx] = rmidi;
		strcpy(rmidi->name, "Virtual Raw MIDI");
		rdev->seq_mode = SNDRV_VIRMIDI_SEQ_DISPATCH;
	}

	strcpy(card->driver, "VirMIDI");
	strcpy(card->shortname, "VirMIDI");
	sprintf(card->longname, "Virtual MIDI Card %i", dev + 1);

	err = snd_card_register(card);
	if (!err) {
		platform_set_drvdata(devptr, card);
		return 0;
	}
__nodev:
	snd_card_free(card);
	return err;
}

static int snd_virmidi_remove(struct platform_device *devptr)
{
	snd_card_free(platform_get_drvdata(devptr));
	return 0;
}

#define SND_VIRMIDI_DRIVER	"snd_virmidi"

static struct platform_driver snd_virmidi_driver = {
	.probe		= snd_virmidi_probe,
	.remove		= snd_virmidi_remove,
	.driver		= {
		.name	= SND_VIRMIDI_DRIVER,
	},
};

static void snd_virmidi_unregister_all(void)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(devices); ++i)
		platform_device_unregister(devices[i]);
	platform_driver_unregister(&snd_virmidi_driver);
}

static int __init alsa_card_virmidi_init(void)
{
	int i, cards, err;

	err = platform_driver_register(&snd_virmidi_driver);
	if (err < 0)
		return err;

	cards = 0;
	for (i = 0; i < SNDRV_CARDS; i++) {
		struct platform_device *device;

		if (!enable[i])
			continue;
		device = platform_device_register_simple(SND_VIRMIDI_DRIVER,
							 i, NULL, 0);
		if (IS_ERR(device))
			continue;
		if (!platform_get_drvdata(device)) {
			platform_device_unregister(device);
			continue;
		}
		devices[i] = device;
		cards++;
	}
	if (!cards) {
#ifdef MODULE
		printk(KERN_ERR "Card-VirMIDI soundcard not found or device busy\n");
#endif
		snd_virmidi_unregister_all();
		return -ENODEV;
	}
	return 0;
}

static void __exit alsa_card_virmidi_exit(void)
{
	snd_virmidi_unregister_all();
}

module_init(alsa_card_virmidi_init)
module_exit(alsa_card_virmidi_exit)

Privacy Policy