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/err.h> 48 #include <linux/platform_device.h> 49 #include <linux/moduleparam.h> 50 #include <sound/core.h> 51 #include <sound/seq_kernel.h> 52 #include <sound/seq_virmidi.h> 53 #include <sound/initval.h> 54 55 /* hack: OSS defines midi_devs, so undefine it (versioned symbols) */ 56 #undef midi_devs 57 58 MODULE_AUTHOR("Takashi Iwai <tiwai@suse.de>"); 59 MODULE_DESCRIPTION("Dummy soundcard for virtual rawmidi devices"); 60 MODULE_LICENSE("GPL"); 61 MODULE_SUPPORTED_DEVICE("{{ALSA,Virtual rawmidi device}}"); 62 63 #define MAX_MIDI_DEVICES 4 64 65 static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX; /* Index 0-MAX */ 66 static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR; /* ID for this card */ 67 static int enable[SNDRV_CARDS] = {1, [1 ... (SNDRV_CARDS - 1)] = 0}; 68 static int midi_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 4}; 69 70 module_param_array(index, int, NULL, 0444); 71 MODULE_PARM_DESC(index, "Index value for virmidi soundcard."); 72 module_param_array(id, charp, NULL, 0444); 73 MODULE_PARM_DESC(id, "ID string for virmidi soundcard."); 74 module_param_array(enable, bool, NULL, 0444); 75 MODULE_PARM_DESC(enable, "Enable this soundcard."); 76 module_param_array(midi_devs, int, NULL, 0444); 77 MODULE_PARM_DESC(midi_devs, "MIDI devices # (1-4)"); 78 79 struct snd_card_virmidi { 80 struct snd_card *card; 81 struct snd_rawmidi *midi[MAX_MIDI_DEVICES]; 82 }; 83 84 static struct platform_device *devices[SNDRV_CARDS]; 85 86 87 static int __devinit snd_virmidi_probe(struct platform_device *devptr) 88 { 89 struct snd_card *card; 90 struct snd_card_virmidi *vmidi; 91 int idx, err; 92 int dev = devptr->id; 93 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 struct snd_rawmidi *rmidi; 107 struct snd_virmidi_dev *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); 119 120 snd_card_set_dev(card, &devptr->dev); 121 122 if ((err = snd_card_register(card)) == 0) { 123 platform_set_drvdata(devptr, card); 124 return 0; 125 } 126 __nodev: 127 snd_card_free(card); 128 return err; 129 } 130 131 static int __devexit snd_virmidi_remove(struct platform_device *devptr) 132 { 133 snd_card_free(platform_get_drvdata(devptr)); 134 platform_set_drvdata(devptr, NULL); 135 return 0; 136 } 137 138 #define SND_VIRMIDI_DRIVER "snd_virmidi" 139 140 static struct platform_driver snd_virmidi_driver = { 141 .probe = snd_virmidi_probe, 142 .remove = __devexit_p(snd_virmidi_remove), 143 .driver = { 144 .name = SND_VIRMIDI_DRIVER 145 }, 146 }; 147 148 static void snd_virmidi_unregister_all(void) 149 { 150 int i; 151 152 for (i = 0; i < ARRAY_SIZE(devices); ++i) 153 platform_device_unregister(devices[i]); 154 platform_driver_unregister(&snd_virmidi_driver); 155 } 156 157 static int __init alsa_card_virmidi_init(void) 158 { 159 int i, cards, err; 160 161 if ((err = platform_driver_register(&snd_virmidi_driver)) < 0) 162 return err; 163 164 cards = 0; 165 for (i = 0; i < SNDRV_CARDS; i++) { 166 struct platform_device *device; 167 if (! enable[i]) 168 continue; 169 device = platform_device_register_simple(SND_VIRMIDI_DRIVER, 170 i, NULL, 0); 171 if (IS_ERR(device)) 172 continue; 173 if (!platform_get_drvdata(device)) { 174 platform_device_unregister(device); 175 continue; 176 } 177 devices[i] = device; 178 cards++; 179 } 180 if (!cards) { 181 #ifdef MODULE 182 printk(KERN_ERR "Card-VirMIDI soundcard not found or device busy\n"); 183 #endif 184 snd_virmidi_unregister_all(); 185 return -ENODEV; 186 } 187 return 0; 188 } 189 190 static void __exit alsa_card_virmidi_exit(void) 191 { 192 snd_virmidi_unregister_all(); 193 } 194 195 module_init(alsa_card_virmidi_init) 196 module_exit(alsa_card_virmidi_exit) 197