sound/core/sound.c

   1 /*
   2  *  Advanced Linux Sound Architecture
   3  *  Copyright (c) by Jaroslav Kysela <perex@suse.cz>
   4  *
   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 #include <sound/driver.h>
  23 #include <linux/init.h>
  24 #include <linux/slab.h>
  25 #include <linux/time.h>
  26 #include <sound/core.h>
  27 #include <sound/minors.h>
  28 #include <sound/info.h>
  29 #include <sound/version.h>
  30 #include <sound/control.h>
  31 #include <sound/initval.h>
  32 #include <linux/kmod.h>
  33 #include <linux/devfs_fs_kernel.h>
  34 #include <linux/device.h>
  35
  36 #define SNDRV_OS_MINORS 256
  37
  38 static int major = CONFIG_SND_MAJOR;
  39 int snd_major;
  40 static int cards_limit = 1;
  41 static int device_mode = S_IFCHR | S_IRUGO | S_IWUGO;
  42
  43 MODULE_AUTHOR("Jaroslav Kysela <perex@suse.cz>");
  44 MODULE_DESCRIPTION("Advanced Linux Sound Architecture driver for soundcards.");
  45 MODULE_LICENSE("GPL");
  46 MODULE_CLASSES("{sound}");
  47 MODULE_SUPPORTED_DEVICE("sound");
  48 MODULE_PARM(major, "i");
  49 MODULE_PARM_DESC(major, "Major # for sound driver.");
  50 MODULE_PARM_SYNTAX(major, "default:116,skill:devel");
  51 MODULE_PARM(cards_limit, "i");
  52 MODULE_PARM_DESC(cards_limit, "Count of auto-loadable soundcards.");
  53 MODULE_PARM_SYNTAX(cards_limit, "default:8,skill:advanced");
  54 MODULE_ALIAS_CHARDEV_MAJOR(CONFIG_SND_MAJOR);
  55 #ifdef CONFIG_DEVFS_FS
  56 MODULE_PARM(device_mode, "i");
  57 MODULE_PARM_DESC(device_mode, "Device file permission mask for devfs.");
  58 MODULE_PARM_SYNTAX(device_mode, "default:0666,base:8");
  59 #endif
  60 MODULE_ALIAS_CHARDEV_MAJOR(CONFIG_SND_MAJOR);
  61
  62 /* this one holds the actual max. card number currently available.
  63  * as default, it's identical with cards_limit option.  when more
  64  * modules are loaded manually, this limit number increases, too.
  65  */
  66 int snd_ecards_limit;
  67
  68 static struct list_head snd_minors_hash[SNDRV_CARDS];
  69
  70 static DECLARE_MUTEX(sound_mutex);
  71
  72 extern struct class_simple *sound_class;
  73
  74
  75 #ifdef CONFIG_KMOD
  76
  77 /**
  78  * snd_request_card - try to load the card module
  79  * @card: the card number
  80  *
  81  * Tries to load the module "snd-card-X" for the given card number
  82  * via KMOD.  Returns immediately if already loaded.
  83  */
  84 void snd_request_card(int card)
  85 {
  86         int locked;
  87
  88         if (! current->fs->root)
  89                 return;
  90         read_lock(&snd_card_rwlock);
  91         locked = snd_cards_lock & (1 << card);
  92         read_unlock(&snd_card_rwlock);
  93         if (locked)
  94                 return;
  95         if (card < 0 || card >= cards_limit)
  96                 return;
  97         request_module("snd-card-%i", card);
  98 }
  99
 100 static void snd_request_other(int minor)
 101 {
 102         char *str;
 103
 104         if (! current->fs->root)
 105                 return;
 106         switch (minor) {
 107         case SNDRV_MINOR_SEQUENCER:     str = "snd-seq";        break;
 108         case SNDRV_MINOR_TIMER:         str = "snd-timer";      break;
 109         default:                        return;
 110         }
 111         request_module(str);
 112 }
 113
 114 #endif                          /* request_module support */
 115
 116 static snd_minor_t *snd_minor_search(int minor)
 117 {
 118         struct list_head *list;
 119         snd_minor_t *mptr;
 120
 121         list_for_each(list, &snd_minors_hash[SNDRV_MINOR_CARD(minor)]) {
 122                 mptr = list_entry(list, snd_minor_t, list);
 123                 if (mptr->number == minor)
 124                         return mptr;
 125         }
 126         return NULL;
 127 }
 128
 129 static int snd_open(struct inode *inode, struct file *file)
 130 {
 131         int minor = iminor(inode);
 132         int card = SNDRV_MINOR_CARD(minor);
 133         int dev = SNDRV_MINOR_DEVICE(minor);
 134         snd_minor_t *mptr = NULL;
 135         struct file_operations *old_fops;
 136         int err = 0;
 137
 138         if (dev != SNDRV_MINOR_SEQUENCER && dev != SNDRV_MINOR_TIMER) {
 139                 if (snd_cards[card] == NULL) {
 140 #ifdef CONFIG_KMOD
 141                         snd_request_card(card);
 142                         if (snd_cards[card] == NULL)
 143 #endif
 144                                 return -ENODEV;
 145                 }
 146         } else {
 147 #ifdef CONFIG_KMOD
 148                 if ((mptr = snd_minor_search(minor)) == NULL)
 149                         snd_request_other(minor);
 150 #endif
 151         }
 152         if (mptr == NULL && (mptr = snd_minor_search(minor)) == NULL)
 153                 return -ENODEV;
 154         old_fops = file->f_op;
 155         file->f_op = fops_get(mptr->f_ops);
 156         if (file->f_op->open)
 157                 err = file->f_op->open(inode, file);
 158         if (err) {
 159                 fops_put(file->f_op);
 160                 file->f_op = fops_get(old_fops);
 161         }
 162         fops_put(old_fops);
 163         return err;
 164 }
 165
 166 struct file_operations snd_fops =
 167 {
 168         .owner =        THIS_MODULE,
 169         .open =         snd_open
 170 };
 171
 172 static int snd_kernel_minor(int type, snd_card_t * card, int dev)
 173 {
 174         int minor;
 175
 176         switch (type) {
 177         case SNDRV_DEVICE_TYPE_SEQUENCER:
 178         case SNDRV_DEVICE_TYPE_TIMER:
 179                 minor = type;
 180                 break;
 181         case SNDRV_DEVICE_TYPE_CONTROL:
 182                 snd_assert(card != NULL, return -EINVAL);
 183                 minor = SNDRV_MINOR(card->number, type);
 184                 break;
 185         case SNDRV_DEVICE_TYPE_HWDEP:
 186         case SNDRV_DEVICE_TYPE_RAWMIDI:
 187         case SNDRV_DEVICE_TYPE_PCM_PLAYBACK:
 188         case SNDRV_DEVICE_TYPE_PCM_CAPTURE:
 189                 snd_assert(card != NULL, return -EINVAL);
 190                 minor = SNDRV_MINOR(card->number, type + dev);
 191                 break;
 192         default:
 193                 return -EINVAL;
 194         }
 195         snd_assert(minor >= 0 && minor < SNDRV_OS_MINORS, return -EINVAL);
 196         return minor;
 197 }
 198
 199 /**
 200  * snd_register_device - Register the ALSA device file for the card
 201  * @type: the device type, SNDRV_DEVICE_TYPE_XXX
 202  * @card: the card instance
 203  * @dev: the device index
 204  * @reg: the snd_minor_t record
 205  * @name: the device file name
 206  *
 207  * Registers an ALSA device file for the given card.
 208  * The operators have to be set in reg parameter.
 209  *
 210  * Retrurns zero if successful, or a negative error code on failure.
 211  */
 212 int snd_register_device(int type, snd_card_t * card, int dev, snd_minor_t * reg, const char *name)
 213 {
 214         int minor = snd_kernel_minor(type, card, dev);
 215         snd_minor_t *preg;
 216         struct device *device = NULL;
 217
 218         if (minor < 0)
 219                 return minor;
 220         snd_assert(name, return -EINVAL);
 221         preg = (snd_minor_t *)kmalloc(sizeof(snd_minor_t) + strlen(name) + 1, GFP_KERNEL);
 222         if (preg == NULL)
 223                 return -ENOMEM;
 224         *preg = *reg;
 225         preg->number = minor;
 226         preg->device = dev;
 227         strcpy(preg->name, name);
 228         down(&sound_mutex);
 229         if (snd_minor_search(minor)) {
 230                 up(&sound_mutex);
 231                 kfree(preg);
 232                 return -EBUSY;
 233         }
 234         list_add_tail(&preg->list, &snd_minors_hash[SNDRV_MINOR_CARD(minor)]);
 235         if (strncmp(name, "controlC", 8) || card->number >= cards_limit) {
 236                 devfs_mk_cdev(MKDEV(major, minor), S_IFCHR | device_mode, "snd/%s", name);
 237                 if (card)
 238                         device = card->dev;
 239                 class_simple_device_add(sound_class, MKDEV(major, minor), device, name);
 240         }
 241
 242         up(&sound_mutex);
 243         return 0;
 244 }
 245
 246 /**
 247  * snd_unregister_device - unregister the device on the given card
 248  * @type: the device type, SNDRV_DEVICE_TYPE_XXX
 249  * @card: the card instance
 250  * @dev: the device index
 251  *
 252  * Unregisters the device file already registered via
 253  * snd_register_device().
 254  *
 255  * Returns zero if sucecessful, or a negative error code on failure
 256  */
 257 int snd_unregister_device(int type, snd_card_t * card, int dev)
 258 {
 259         int minor = snd_kernel_minor(type, card, dev);
 260         snd_minor_t *mptr;
 261
 262         if (minor < 0)
 263                 return minor;
 264         down(&sound_mutex);
 265         if ((mptr = snd_minor_search(minor)) == NULL) {
 266                 up(&sound_mutex);
 267                 return -EINVAL;
 268         }
 269
 270         if (strncmp(mptr->name, "controlC", 8) || card->number >= cards_limit) { /* created in sound.c */
 271                 devfs_remove("snd/%s", mptr->name);
 272                 class_simple_device_remove(MKDEV(major, minor));
 273         }
 274
 275         list_del(&mptr->list);
 276         up(&sound_mutex);
 277         kfree(mptr);
 278         return 0;
 279 }
 280
 281 /*
 282  *  INFO PART
 283  */
 284
 285 static snd_info_entry_t *snd_minor_info_entry = NULL;
 286
 287 static void snd_minor_info_read(snd_info_entry_t *entry, snd_info_buffer_t * buffer)
 288 {
 289         int card, device;
 290         struct list_head *list;
 291         snd_minor_t *mptr;
 292
 293         down(&sound_mutex);
 294         for (card = 0; card < SNDRV_CARDS; card++) {
 295                 list_for_each(list, &snd_minors_hash[card]) {
 296                         mptr = list_entry(list, snd_minor_t, list);
 297                         if (SNDRV_MINOR_DEVICE(mptr->number) != SNDRV_MINOR_SEQUENCER) {
 298                                 if ((device = mptr->device) >= 0)
 299                                         snd_iprintf(buffer, "%3i: [%i-%2i]: %s\n", mptr->number, card, device, mptr->comment);
 300                                 else
 301                                         snd_iprintf(buffer, "%3i: [%i]   : %s\n", mptr->number, card, mptr->comment);
 302                         } else {
 303                                 snd_iprintf(buffer, "%3i:       : %s\n", mptr->number, mptr->comment);
 304                         }
 305                 }
 306         }
 307         up(&sound_mutex);
 308 }
 309
 310 int __init snd_minor_info_init(void)
 311 {
 312         snd_info_entry_t *entry;
 313
 314         entry = snd_info_create_module_entry(THIS_MODULE, "devices", NULL);
 315         if (entry) {
 316                 entry->c.text.read_size = PAGE_SIZE;
 317                 entry->c.text.read = snd_minor_info_read;
 318                 if (snd_info_register(entry) < 0) {
 319                         snd_info_free_entry(entry);
 320                         entry = NULL;
 321                 }
 322         }
 323         snd_minor_info_entry = entry;
 324         return 0;
 325 }
 326
 327 int __exit snd_minor_info_done(void)
 328 {
 329         if (snd_minor_info_entry)
 330                 snd_info_unregister(snd_minor_info_entry);
 331         return 0;
 332 }
 333
 334 /*
 335  *  INIT PART
 336  */
 337
 338 static int __init alsa_sound_init(void)
 339 {
 340         short controlnum;
 341 #ifdef CONFIG_SND_OSSEMUL
 342         int err;
 343 #endif
 344         int card;
 345
 346         snd_major = major;
 347         snd_ecards_limit = cards_limit;
 348         for (card = 0; card < SNDRV_CARDS; card++)
 349                 INIT_LIST_HEAD(&snd_minors_hash[card]);
 350 #ifdef CONFIG_SND_OSSEMUL
 351         if ((err = snd_oss_init_module()) < 0)
 352                 return err;
 353 #endif
 354         devfs_mk_dir("snd");
 355         if (register_chrdev(major, "alsa", &snd_fops)) {
 356                 snd_printk(KERN_ERR "unable to register native major device number %d\n", major);
 357                 devfs_remove("snd");
 358                 return -EIO;
 359         }
 360 #ifdef CONFIG_SND_DEBUG_MEMORY
 361         snd_memory_init();
 362 #endif
 363         if (snd_info_init() < 0) {
 364 #ifdef CONFIG_SND_DEBUG_MEMORY
 365                 snd_memory_done();
 366 #endif
 367                 unregister_chrdev(major, "alsa");
 368                 devfs_remove("snd");
 369                 return -ENOMEM;
 370         }
 371 #ifdef CONFIG_SND_OSSEMUL
 372         snd_info_minor_register();
 373 #endif
 374         for (controlnum = 0; controlnum < cards_limit; controlnum++) {
 375                 devfs_mk_cdev(MKDEV(major, controlnum<<5), S_IFCHR | device_mode, "snd/controlC%d", controlnum);
 376                 class_simple_device_add(sound_class, MKDEV(major, controlnum<<5), NULL, "controlC%d", controlnum);
 377         }
 378 #ifndef MODULE
 379         printk(KERN_INFO "Advanced Linux Sound Architecture Driver Version " CONFIG_SND_VERSION CONFIG_SND_DATE ".\n");
 380 #endif
 381         return 0;
 382 }
 383
 384 static void __exit alsa_sound_exit(void)
 385 {
 386         short controlnum;
 387
 388         for (controlnum = 0; controlnum < cards_limit; controlnum++) {
 389                 devfs_remove("snd/controlC%d", controlnum);
 390                 class_simple_device_remove(MKDEV(major, controlnum<<5));
 391         }
 392
 393 #ifdef CONFIG_SND_OSSEMUL
 394         snd_info_minor_unregister();
 395 #endif
 396         snd_info_done();
 397 #ifdef CONFIG_SND_DEBUG_MEMORY
 398         snd_memory_done();
 399 #endif
 400         if (unregister_chrdev(major, "alsa") != 0)
 401                 snd_printk(KERN_ERR "unable to unregister major device number %d\n", major);
 402         devfs_remove("snd");
 403 }
 404
 405 module_init(alsa_sound_init)
 406 module_exit(alsa_sound_exit)
 407
 408 #ifndef MODULE
 409
 410 /* format is: snd=major,cards_limit[,device_mode] */
 411
 412 static int __init alsa_sound_setup(char *str)
 413 {
 414         (void)(get_option(&str,&major) == 2 &&
 415                get_option(&str,&cards_limit) == 2);
 416 #ifdef CONFIG_DEVFS_FS
 417         (void)(get_option(&str,&device_mode) == 2);
 418 #endif
 419         return 1;
 420 }
 421
 422 __setup("snd=", alsa_sound_setup);
 423
 424 #endif /* ifndef MODULE */
 425
 426   /* sound.c */
 427 EXPORT_SYMBOL(snd_major);
 428 EXPORT_SYMBOL(snd_ecards_limit);
 429 #if defined(CONFIG_KMOD)
 430 EXPORT_SYMBOL(snd_request_card);
 431 #endif
 432 EXPORT_SYMBOL(snd_register_device);
 433 EXPORT_SYMBOL(snd_unregister_device);
 434 #if defined(CONFIG_SND_OSSEMUL)
 435 EXPORT_SYMBOL(snd_register_oss_device);
 436 EXPORT_SYMBOL(snd_unregister_oss_device);
 437 #endif
 438   /* memory.c */
 439 #ifdef CONFIG_SND_DEBUG_MEMORY
 440 EXPORT_SYMBOL(snd_hidden_kmalloc);
 441 EXPORT_SYMBOL(snd_hidden_kfree);
 442 EXPORT_SYMBOL(snd_hidden_vmalloc);
 443 EXPORT_SYMBOL(snd_hidden_vfree);
 444 EXPORT_SYMBOL(_snd_magic_kmalloc);
 445 EXPORT_SYMBOL(_snd_magic_kcalloc);
 446 EXPORT_SYMBOL(snd_magic_kfree);
 447 #endif
 448 EXPORT_SYMBOL(snd_kcalloc);
 449 EXPORT_SYMBOL(snd_kmalloc_strdup);
 450 EXPORT_SYMBOL(copy_to_user_fromio);
 451 EXPORT_SYMBOL(copy_from_user_toio);
 452   /* init.c */
 453 EXPORT_SYMBOL(snd_cards_count);
 454 EXPORT_SYMBOL(snd_cards);
 455 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
 456 EXPORT_SYMBOL(snd_mixer_oss_notify_callback);
 457 #endif
 458 EXPORT_SYMBOL(snd_card_new);
 459 EXPORT_SYMBOL(snd_card_disconnect);
 460 EXPORT_SYMBOL(snd_card_free);
 461 EXPORT_SYMBOL(snd_card_free_in_thread);
 462 EXPORT_SYMBOL(snd_card_register);
 463 EXPORT_SYMBOL(snd_component_add);
 464 EXPORT_SYMBOL(snd_card_file_add);
 465 EXPORT_SYMBOL(snd_card_file_remove);
 466 #ifdef CONFIG_PM
 467 EXPORT_SYMBOL(snd_power_wait);
 468 #endif
 469   /* device.c */
 470 EXPORT_SYMBOL(snd_device_new);
 471 EXPORT_SYMBOL(snd_device_register);
 472 EXPORT_SYMBOL(snd_device_free);
 473 EXPORT_SYMBOL(snd_device_free_all);
 474   /* isadma.c */
 475 #ifdef CONFIG_ISA
 476 EXPORT_SYMBOL(snd_dma_program);
 477 EXPORT_SYMBOL(snd_dma_disable);
 478 EXPORT_SYMBOL(snd_dma_pointer);
 479 #endif
 480   /* info.c */
 481 #ifdef CONFIG_PROC_FS
 482 EXPORT_SYMBOL(snd_seq_root);
 483 EXPORT_SYMBOL(snd_create_proc_entry);
 484 EXPORT_SYMBOL(snd_remove_proc_entry);
 485 EXPORT_SYMBOL(snd_iprintf);
 486 EXPORT_SYMBOL(snd_info_get_line);
 487 EXPORT_SYMBOL(snd_info_get_str);
 488 EXPORT_SYMBOL(snd_info_create_module_entry);
 489 EXPORT_SYMBOL(snd_info_create_card_entry);
 490 EXPORT_SYMBOL(snd_info_free_entry);
 491 EXPORT_SYMBOL(snd_info_register);
 492 EXPORT_SYMBOL(snd_info_unregister);
 493 EXPORT_SYMBOL(snd_card_proc_new);
 494 #endif
 495   /* info_oss.c */
 496 #if defined(CONFIG_SND_OSSEMUL) && defined(CONFIG_PROC_FS)
 497 EXPORT_SYMBOL(snd_oss_info_register);
 498 #endif
 499   /* control.c */
 500 EXPORT_SYMBOL(snd_ctl_new);
 501 EXPORT_SYMBOL(snd_ctl_new1);
 502 EXPORT_SYMBOL(snd_ctl_free_one);
 503 EXPORT_SYMBOL(snd_ctl_add);
 504 EXPORT_SYMBOL(snd_ctl_remove);
 505 EXPORT_SYMBOL(snd_ctl_remove_id);
 506 EXPORT_SYMBOL(snd_ctl_rename_id);
 507 EXPORT_SYMBOL(snd_ctl_find_numid);
 508 EXPORT_SYMBOL(snd_ctl_find_id);
 509 EXPORT_SYMBOL(snd_ctl_notify);
 510 EXPORT_SYMBOL(snd_ctl_register_ioctl);
 511 EXPORT_SYMBOL(snd_ctl_unregister_ioctl);
 512   /* misc.c */
 513 EXPORT_SYMBOL(snd_task_name);
 514 #ifdef CONFIG_SND_VERBOSE_PRINTK
 515 EXPORT_SYMBOL(snd_verbose_printk);
 516 #endif
 517 #if defined(CONFIG_SND_DEBUG) && defined(CONFIG_SND_VERBOSE_PRINTK)
 518 EXPORT_SYMBOL(snd_verbose_printd);
 519 #endif
 520   /* wrappers */
 521 #ifdef CONFIG_SND_DEBUG_MEMORY
 522 EXPORT_SYMBOL(snd_wrapper_kmalloc);
 523 EXPORT_SYMBOL(snd_wrapper_kfree);
 524 EXPORT_SYMBOL(snd_wrapper_vmalloc);
 525 EXPORT_SYMBOL(snd_wrapper_vfree);
 526 #endif