1/*
2 *  Dummy soundcard for virtual rawmidi devices
3 *
4 *  Copyright (c) 2000 by Takashi Iwai <tiwai@suse.de>
5 *
6 *   This program is free software; you can redistribute it and/or modify
7 *   it under the terms of the GNU General Public License as published by
8 *   the Free Software Foundation; either version 2 of the License, or
9 *   (at your option) any later version.
10 *
11 *   This program is distributed in the hope that it will be useful,
12 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
13 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14 *   GNU General Public License for more details.
15 *
16 *   You should have received a copy of the GNU General Public License
17 *   along with this program; if not, write to the Free Software
18 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
19 *
20 */
21
22/*
23 * VIRTUAL RAW MIDI DEVICE CARDS
24 *
25 * This dummy card contains up to 4 virtual rawmidi devices.
26 * They are not real rawmidi devices but just associated with sequencer
27 * clients, so that any input/output sources can be connected as a raw
28 * MIDI device arbitrary.
29 * Also, multiple access is allowed to a single rawmidi device.
30 *
31 * Typical usage is like following:
32 * - Load snd-virmidi module.
33 *	# modprobe snd-virmidi index=2
34 *   Then, sequencer clients 72:0 to 75:0 will be created, which are
35 *   mapped from /dev/snd/midiC1D0 to /dev/snd/midiC1D3, respectively.
36 *
37 * - Connect input/output via aconnect.
38 *	% aconnect 64:0 72:0	# keyboard input redirection 64:0 -> 72:0
39 *	% aconnect 72:0 65:0	# output device redirection 72:0 -> 65:0
40 *
41 * - Run application using a midi device (eg. /dev/snd/midiC1D0)
42 */
43
44#include <linux/init.h>
45#include <linux/wait.h>
46#include <linux/err.h>
47#include <linux/platform_device.h>
48#include <linux/module.h>
49#include <sound/core.h>
50#include <sound/seq_kernel.h>
51#include <sound/seq_virmidi.h>
52#include <sound/initval.h>
53
54/* hack: OSS defines midi_devs, so undefine it (versioned symbols) */
55#undef midi_devs
56
57MODULE_AUTHOR("Takashi Iwai <tiwai@suse.de>");
58MODULE_DESCRIPTION("Dummy soundcard for virtual rawmidi devices");
59MODULE_LICENSE("GPL");
60MODULE_SUPPORTED_DEVICE("{{ALSA,Virtual rawmidi device}}");
61
62#define MAX_MIDI_DEVICES	4
63
64static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;	/* Index 0-MAX */
65static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;	/* ID for this card */
66static bool enable[SNDRV_CARDS] = {1, [1 ... (SNDRV_CARDS - 1)] = 0};
67static int midi_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 4};
68
69module_param_array(index, int, NULL, 0444);
70MODULE_PARM_DESC(index, "Index value for virmidi soundcard.");
71module_param_array(id, charp, NULL, 0444);
72MODULE_PARM_DESC(id, "ID string for virmidi soundcard.");
73module_param_array(enable, bool, NULL, 0444);
74MODULE_PARM_DESC(enable, "Enable this soundcard.");
75module_param_array(midi_devs, int, NULL, 0444);
76MODULE_PARM_DESC(midi_devs, "MIDI devices # (1-4)");
77
78struct snd_card_virmidi {
79	struct snd_card *card;
80	struct snd_rawmidi *midi[MAX_MIDI_DEVICES];
81};
82
83static struct platform_device *devices[SNDRV_CARDS];
84
85
86static int snd_virmidi_probe(struct platform_device *devptr)
87{
88	struct snd_card *card;
89	struct snd_card_virmidi *vmidi;
90	int idx, err;
91	int dev = devptr->id;
92
93	err = snd_card_new(&devptr->dev, index[dev], id[dev], THIS_MODULE,
94			   sizeof(struct snd_card_virmidi), &card);
95	if (err < 0)
96		return err;
97	vmidi = card->private_data;
98	vmidi->card = card;
99
100	if (midi_devs[dev] > MAX_MIDI_DEVICES) {
101		snd_printk(KERN_WARNING
102			   "too much midi devices for virmidi %d: force to use %d\n",
103			   dev, MAX_MIDI_DEVICES);
104		midi_devs[dev] = MAX_MIDI_DEVICES;
105	}
106	for (idx = 0; idx < midi_devs[dev]; idx++) {
107		struct snd_rawmidi *rmidi;
108		struct snd_virmidi_dev *rdev;
109
110		err = snd_virmidi_new(card, idx, &rmidi);
111		if (err < 0)
112			goto __nodev;
113		rdev = rmidi->private_data;
114		vmidi->midi[idx] = rmidi;
115		strcpy(rmidi->name, "Virtual Raw MIDI");
116		rdev->seq_mode = SNDRV_VIRMIDI_SEQ_DISPATCH;
117	}
118
119	strcpy(card->driver, "VirMIDI");
120	strcpy(card->shortname, "VirMIDI");
121	sprintf(card->longname, "Virtual MIDI Card %i", dev + 1);
122
123	err = snd_card_register(card);
124	if (!err) {
125		platform_set_drvdata(devptr, card);
126		return 0;
127	}
128__nodev:
129	snd_card_free(card);
130	return err;
131}
132
133static int snd_virmidi_remove(struct platform_device *devptr)
134{
135	snd_card_free(platform_get_drvdata(devptr));
136	return 0;
137}
138
139#define SND_VIRMIDI_DRIVER	"snd_virmidi"
140
141static struct platform_driver snd_virmidi_driver = {
142	.probe		= snd_virmidi_probe,
143	.remove		= snd_virmidi_remove,
144	.driver		= {
145		.name	= SND_VIRMIDI_DRIVER,
146	},
147};
148
149static void snd_virmidi_unregister_all(void)
150{
151	int i;
152
153	for (i = 0; i < ARRAY_SIZE(devices); ++i)
154		platform_device_unregister(devices[i]);
155	platform_driver_unregister(&snd_virmidi_driver);
156}
157
158static int __init alsa_card_virmidi_init(void)
159{
160	int i, cards, err;
161
162	err = platform_driver_register(&snd_virmidi_driver);
163	if (err < 0)
164		return err;
165
166	cards = 0;
167	for (i = 0; i < SNDRV_CARDS; i++) {
168		struct platform_device *device;
169
170		if (!enable[i])
171			continue;
172		device = platform_device_register_simple(SND_VIRMIDI_DRIVER,
173							 i, NULL, 0);
174		if (IS_ERR(device))
175			continue;
176		if (!platform_get_drvdata(device)) {
177			platform_device_unregister(device);
178			continue;
179		}
180		devices[i] = device;
181		cards++;
182	}
183	if (!cards) {
184#ifdef MODULE
185		printk(KERN_ERR "Card-VirMIDI soundcard not found or device busy\n");
186#endif
187		snd_virmidi_unregister_all();
188		return -ENODEV;
189	}
190	return 0;
191}
192
193static void __exit alsa_card_virmidi_exit(void)
194{
195	snd_virmidi_unregister_all();
196}
197
198module_init(alsa_card_virmidi_init)
199module_exit(alsa_card_virmidi_exit)
200