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 <sound/driver.h> 45 #include <linux/init.h> 46 #include <linux/wait.h> 47 #include <linux/sched.h> 48 #include <linux/moduleparam.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 57 MODULE_AUTHOR("Takashi Iwai <tiwai@suse.de>"); 58 MODULE_DESCRIPTION("Dummy soundcard for virtual rawmidi devices"); 59 MODULE_LICENSE("GPL"); 60 MODULE_SUPPORTED_DEVICE("{{ALSA,Virtual rawmidi device}}"); 61 62 #define MAX_MIDI_DEVICES 8 63 64 static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX; /* Index 0-MAX */ 65 static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR; /* ID for this card */ 66 static int enable[SNDRV_CARDS] = {1, [1 ... (SNDRV_CARDS - 1)] = 0}; 67 static int midi_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 4}; 68 69 module_param_array(index, int, NULL, 0444); 70 MODULE_PARM_DESC(index, "Index value for virmidi soundcard."); 71 module_param_array(id, charp, NULL, 0444); 72 MODULE_PARM_DESC(id, "ID string for virmidi soundcard."); 73 module_param_array(enable, bool, NULL, 0444); 74 MODULE_PARM_DESC(enable, "Enable this soundcard."); 75 module_param_array(midi_devs, int, NULL, 0444); 76 MODULE_PARM_DESC(midi_devs, "MIDI devices # (1-8)"); 77 78 typedef struct snd_card_virmidi { 79 snd_card_t *card; 80 snd_rawmidi_t *midi[MAX_MIDI_DEVICES]; 81 } snd_card_virmidi_t; 82 83 static snd_card_t *snd_virmidi_cards[SNDRV_CARDS] = SNDRV_DEFAULT_PTR; 84 85 86 static int __init snd_card_virmidi_probe(int dev) 87 { 88 snd_card_t *card; 89 struct snd_card_virmidi *vmidi; 90 int idx, err; 91 92 if (!enable[dev]) 93 return -ENODEV; 94 card = snd_card_new(index[dev], id[dev], THIS_MODULE, 95 sizeof(struct snd_card_virmidi)); 96 if (card == NULL) 97 return -ENOMEM; 98 vmidi = (struct snd_card_virmidi *)card->private_data; 99 vmidi->card = card; 100 101 if (midi_devs[dev] > MAX_MIDI_DEVICES) { 102 snd_printk("too much midi devices for virmidi %d: force to use %d\n", dev, MAX_MIDI_DEVICES); 103 midi_devs[dev] = MAX_MIDI_DEVICES; 104 } 105 for (idx = 0; idx < midi_devs[dev]; idx++) { 106 snd_rawmidi_t *rmidi; 107 snd_virmidi_dev_t *rdev; 108 if ((err = snd_virmidi_new(card, idx, &rmidi)) < 0) 109 goto __nodev; 110 rdev = rmidi->private_data; 111 vmidi->midi[idx] = rmidi; 112 strcpy(rmidi->name, "Virtual Raw MIDI"); 113 rdev->seq_mode = SNDRV_VIRMIDI_SEQ_DISPATCH; 114 } 115 116 strcpy(card->driver, "VirMIDI"); 117 strcpy(card->shortname, "VirMIDI"); 118 sprintf(card->longname, "Virtual MIDI Card %i", dev + 1); 119 if ((err = snd_card_register(card)) == 0) { 120 snd_virmidi_cards[dev] = card; 121 return 0; 122 } 123 __nodev: 124 snd_card_free(card); 125 return err; 126 } 127 128 static int __init alsa_card_virmidi_init(void) 129 { 130 int dev, cards; 131 132 for (dev = cards = 0; dev < SNDRV_CARDS && enable[dev]; dev++) { 133 if (snd_card_virmidi_probe(dev) < 0) { 134 #ifdef MODULE 135 printk(KERN_ERR "Card-VirMIDI #%i not found or device busy\n", dev + 1); 136 #endif 137 break; 138 } 139 cards++; 140 } 141 if (!cards) { 142 #ifdef MODULE 143 printk(KERN_ERR "Card-VirMIDI soundcard not found or device busy\n"); 144 #endif 145 return -ENODEV; 146 } 147 return 0; 148 } 149 150 static void __exit alsa_card_virmidi_exit(void) 151 { 152 int dev; 153 154 for (dev = 0; dev < SNDRV_CARDS; dev++) 155 snd_card_free(snd_virmidi_cards[dev]); 156 } 157 158 module_init(alsa_card_virmidi_init) 159 module_exit(alsa_card_virmidi_exit) 160