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 <linux/moduleparam.h>
  27 #include <sound/core.h>
  28 #include <sound/minors.h>
  29 #include <sound/info.h>
  30 #include <sound/version.h>
  31 #include <sound/control.h>
  32 #include <sound/initval.h>
  33 #include <linux/kmod.h>
  34 #include <linux/devfs_fs_kernel.h>
  35 #include <linux/device.h>
  36
  37 #define SNDRV_OS_MINORS 256
  38
  39 static int major = CONFIG_SND_MAJOR;
  40 int snd_major;
  41 static int cards_limit = 1;
  42 static int device_mode = S_IFCHR | S_IRUGO | S_IWUGO;
  43
  44 MODULE_AUTHOR("Jaroslav Kysela <perex@suse.cz>");
  45 MODULE_DESCRIPTION("Advanced Linux Sound Architecture driver for soundcards.");
  46 MODULE_LICENSE("GPL");
  47 MODULE_CLASSES("{sound}");
  48 MODULE_SUPPORTED_DEVICE("sound");
  49 module_param(major, int, 0444);
  50 MODULE_PARM_DESC(major, "Major # for sound driver.");
  51 MODULE_PARM_SYNTAX(major, "default:116,skill:devel");
  52 module_param(cards_limit, int, 0444);
  53 MODULE_PARM_DESC(cards_limit, "Count of auto-loadable soundcards.");
  54 MODULE_PARM_SYNTAX(cards_limit, "default:8,skill:advanced");
  55 MODULE_ALIAS_CHARDEV_MAJOR(CONFIG_SND_MAJOR);
  56 #ifdef CONFIG_DEVFS_FS
  57 module_param(device_mode, int, 0444);
  58 MODULE_PARM_DESC(device_mode, "Device file permission mask for devfs.");
  59 MODULE_PARM_SYNTAX(device_mode, "default:0666,base:8");
  60 #endif
  61 MODULE_ALIAS_CHARDEV_MAJOR(CONFIG_SND_MAJOR);
  62
  63 /* this one holds the actual max. card number currently available.
  64  * as default, it's identical with cards_limit option.  when more
  65  * modules are loaded manually, this limit number increases, too.
  66  */
  67 int snd_ecards_limit;
  68
  69 static struct list_head snd_minors_hash[SNDRV_CARDS];
  70
  71 static DECLARE_MUTEX(sound_mutex);
  72
  73 extern struct class_simple *sound_class;
  74
  75
  76 #ifdef CONFIG_KMOD
  77
  78 /**
  79  * snd_request_card - try to load the card module
  80  * @card: the card number
  81  *
  82  * Tries to load the module "snd-card-X" for the given card number
  83  * via KMOD.  Returns immediately if already loaded.
  84  */
  85 void snd_request_card(int card)
  86 {
  87         int locked;
  88
  89         if (! current->fs->root)
  90                 return;
  91         read_lock(&snd_card_rwlock);
  92         locked = snd_cards_lock & (1 << card);
  93         read_unlock(&snd_card_rwlock);
  94         if (locked)
  95                 return;
  96         if (card < 0 || card >= cards_limit)
  97                 return;
  98         request_module("snd-card-%i", card);
  99 }
 100
 101 static void snd_request_other(int minor)
 102 {
 103         char *str;
 104
 105         if (! current->fs->root)
 106                 return;
 107         switch (minor) {
 108         case SNDRV_MINOR_SEQUENCER:     str = "snd-seq";        break;
 109         case SNDRV_MINOR_TIMER:         str = "snd-timer";      break;
 110         default:                        return;
 111         }
 112         request_module(str);
 113 }
 114
 115 #endif                          /* request_module support */
 116
 117 static snd_minor_t *snd_minor_search(int minor)
 118 {
 119         struct list_head *list;
 120         snd_minor_t *mptr;
 121
 122         list_for_each(list, &snd_minors_hash[SNDRV_MINOR_CARD(minor)]) {
 123                 mptr = list_entry(list, snd_minor_t, list);
 124                 if (mptr->number == minor)
 125                         return mptr;
 126         }
 127         return NULL;
 128 }
 129
 130 static int snd_open(struct inode *inode, struct file *file)
 131 {
 132         int minor = iminor(inode);
 133         int card = SNDRV_MINOR_CARD(minor);
 134         int dev = SNDRV_MINOR_DEVICE(minor);
 135         snd_minor_t *mptr = NULL;
 136         struct file_operations *old_fops;
 137         int err = 0;
 138
 139         if (dev != SNDRV_MINOR_SEQUENCER && dev != SNDRV_MINOR_TIMER) {
 140                 if (snd_cards[card] == NULL) {
 141 #ifdef CONFIG_KMOD
 142                         snd_request_card(card);
 143                         if (snd_cards[card] == NULL)
 144 #endif
 145                                 return -ENODEV;
 146                 }
 147         } else {
 148 #ifdef CONFIG_KMOD
 149                 if ((mptr = snd_minor_search(minor)) == NULL)
 150                         snd_request_other(minor);
 151 #endif
 152         }
 153         if (mptr == NULL && (mptr = snd_minor_search(minor)) == NULL)
 154                 return -ENODEV;
 155         old_fops = file->f_op;
 156         file->f_op = fops_get(mptr->f_ops);
 157         if (file->f_op->open)
 158                 err = file->f_op->open(inode, file);
 159         if (err) {
 160                 fops_put(file->f_op);
 161                 file->f_op = fops_get(old_fops);
 162         }
 163         fops_put(old_fops);
 164         return err;
 165 }
 166
 167 struct file_operations snd_fops =
 168 {
 169         .owner =        THIS_MODULE,
 170         .open =         snd_open
 171 };
 172
 173 static int snd_kernel_minor(int type, snd_card_t * card, int dev)
 174 {
 175         int minor;
 176
 177         switch (type) {
 178         case SNDRV_DEVICE_TYPE_SEQUENCER:
 179         case SNDRV_DEVICE_TYPE_TIMER:
 180                 minor = type;
 181                 break;
 182         case SNDRV_DEVICE_TYPE_CONTROL:
 183                 snd_assert(card != NULL, return -EINVAL);
 184                 minor = SNDRV_MINOR(card->number, type);
 185                 break;
 186         case SNDRV_DEVICE_TYPE_HWDEP:
 187         case SNDRV_DEVICE_TYPE_RAWMIDI:
 188         case SNDRV_DEVICE_TYPE_PCM_PLAYBACK:
 189         case SNDRV_DEVICE_TYPE_PCM_CAPTURE:
 190                 snd_assert(card != NULL, return -EINVAL);
 191                 minor = SNDRV_MINOR(card->number, type + dev);
 192                 break;
 193         default:
 194                 return -EINVAL;
 195         }
 196         snd_assert(minor >= 0 && minor < SNDRV_OS_MINORS, return -EINVAL);
 197         return minor;
 198 }
 199
 200 /**
 201  * snd_register_device - Register the ALSA device file for the card
 202  * @type: the device type, SNDRV_DEVICE_TYPE_XXX
 203  * @card: the card instance
 204  * @dev: the device index
 205  * @reg: the snd_minor_t record
 206  * @name: the device file name
 207  *
 208  * Registers an ALSA device file for the given card.
 209  * The operators have to be set in reg parameter.
 210  *
 211  * Retrurns zero if successful, or a negative error code on failure.
 212  */
 213 int snd_register_device(int type, snd_card_t * card, int dev, snd_minor_t * reg, const char *name)
 214 {
 215         int minor = snd_kernel_minor(type, card, dev);
 216         snd_minor_t *preg;
 217         struct device *device = NULL;
 218
 219         if (minor < 0)
 220                 return minor;
 221         snd_assert(name, return -EINVAL);
 222         preg = (snd_minor_t *)kmalloc(sizeof(snd_minor_t) + strlen(name) + 1, GFP_KERNEL);
 223         if (preg == NULL)
 224                 return -ENOMEM;
 225         *preg = *reg;
 226         preg->number = minor;
 227         preg->device = dev;
 228         strcpy(preg->name, name);
 229         down(&sound_mutex);
 230         if (snd_minor_search(minor)) {
 231                 up(&sound_mutex);
 232                 kfree(preg);
 233                 return -EBUSY;
 234         }
 235         list_add_tail(&preg->list, &snd_minors_hash[SNDRV_MINOR_CARD(minor)]);
 236         if (strncmp(name, "controlC", 8) || card->number >= cards_limit) {
 237                 devfs_mk_cdev(MKDEV(major, minor), S_IFCHR | device_mode, "snd/%s", name);
 238                 if (card)
 239                         device = card->dev;
 240                 class_simple_device_add(sound_class, MKDEV(major, minor), device, name);
 241         }
 242
 243         up(&sound_mutex);
 244         return 0;
 245 }
 246
 247 /**
 248  * snd_unregister_device - unregister the device on the given card
 249  * @type: the device type, SNDRV_DEVICE_TYPE_XXX
 250  * @card: the card instance
 251  * @dev: the device index
 252  *
 253  * Unregisters the device file already registered via
 254  * snd_register_device().
 255  *
 256  * Returns zero if sucecessful, or a negative error code on failure
 257  */
 258 int snd_unregister_device(int type, snd_card_t * card, int dev)
 259 {
 260         int minor = snd_kernel_minor(type, card, dev);
 261         snd_minor_t *mptr;
 262
 263         if (minor < 0)
 264                 return minor;
 265         down(&sound_mutex);
 266         if ((mptr = snd_minor_search(minor)) == NULL) {
 267                 up(&sound_mutex);
 268                 return -EINVAL;
 269         }
 270
 271         if (strncmp(mptr->name, "controlC", 8) || card->number >= cards_limit) { /* created in sound.c */
 272                 devfs_remove("snd/%s", mptr->name);
 273                 class_simple_device_remove(MKDEV(major, minor));
 274         }
 275
 276         list_del(&mptr->list);
 277         up(&sound_mutex);
 278         kfree(mptr);
 279         return 0;
 280 }
 281
 282 /*
 283  *  INFO PART
 284  */
 285
 286 static snd_info_entry_t *snd_minor_info_entry = NULL;
 287
 288 static void snd_minor_info_read(snd_info_entry_t *entry, snd_info_buffer_t * buffer)
 289 {
 290         int card, device;
 291         struct list_head *list;
 292         snd_minor_t *mptr;
 293
 294         down(&sound_mutex);
 295         for (card = 0; card < SNDRV_CARDS; card++) {
 296                 list_for_each(list, &snd_minors_hash[card]) {
 297                         mptr = list_entry(list, snd_minor_t, list);
 298                         if (SNDRV_MINOR_DEVICE(mptr->number) != SNDRV_MINOR_SEQUENCER) {
 299                                 if ((device = mptr->device) >= 0)
 300                                         snd_iprintf(buffer, "%3i: [%i-%2i]: %s\n", mptr->number, card, device, mptr->comment);
 301                                 else
 302                                         snd_iprintf(buffer, "%3i: [%i]   : %s\n", mptr->number, card, mptr->comment);
 303                         } else {
 304                                 snd_iprintf(buffer, "%3i:       : %s\n", mptr->number, mptr->comment);
 305                         }
 306                 }
 307         }
 308         up(&sound_mutex);
 309 }
 310
 311 int __init snd_minor_info_init(void)
 312 {
 313         snd_info_entry_t *entry;
 314
 315         entry = snd_info_create_module_entry(THIS_MODULE, "devices", NULL);
 316         if (entry) {
 317                 entry->c.text.read_size = PAGE_SIZE;
 318                 entry->c.text.read = snd_minor_info_read;
 319                 if (snd_info_register(entry) < 0) {
 320                         snd_info_free_entry(entry);
 321                         entry = NULL;
 322                 }
 323         }
 324         snd_minor_info_entry = entry;
 325         return 0;
 326 }
 327
 328 int __exit snd_minor_info_done(void)
 329 {
 330         if (snd_minor_info_entry)
 331                 snd_info_unregister(snd_minor_info_entry);
 332         return 0;
 333 }
 334
 335 /*
 336  *  INIT PART
 337  */
 338
 339 static int __init alsa_sound_init(void)
 340 {
 341         short controlnum;
 342 #ifdef CONFIG_SND_OSSEMUL
 343         int err;
 344 #endif
 345         int card;
 346
 347         snd_major = major;
 348         snd_ecards_limit = cards_limit;
 349         for (card = 0; card < SNDRV_CARDS; card++)
 350                 INIT_LIST_HEAD(&snd_minors_hash[card]);
 351 #ifdef CONFIG_SND_OSSEMUL
 352         if ((err = snd_oss_init_module()) < 0)
 353                 return err;
 354 #endif
 355         devfs_mk_dir("snd");
 356         if (register_chrdev(major, "alsa", &snd_fops)) {
 357                 snd_printk(KERN_ERR "unable to register native major device number %d\n", major);
 358                 devfs_remove("snd");
 359                 return -EIO;
 360         }
 361 #ifdef CONFIG_SND_DEBUG_MEMORY
 362         snd_memory_init();
 363 #endif
 364         if (snd_info_init() < 0) {
 365 #ifdef CONFIG_SND_DEBUG_MEMORY
 366                 snd_memory_done();
 367 #endif
 368                 unregister_chrdev(major, "alsa");
 369                 devfs_remove("snd");
 370                 return -ENOMEM;
 371         }
 372 #ifdef CONFIG_SND_OSSEMUL
 373         snd_info_minor_register();
 374 #endif
 375         for (controlnum = 0; controlnum < cards_limit; controlnum++) {
 376                 devfs_mk_cdev(MKDEV(major, controlnum<<5), S_IFCHR | device_mode, "snd/controlC%d", controlnum);
 377                 class_simple_device_add(sound_class, MKDEV(major, controlnum<<5), NULL, "controlC%d", controlnum);
 378         }
 379 #ifndef MODULE
 380         printk(KERN_INFO "Advanced Linux Sound Architecture Driver Version " CONFIG_SND_VERSION CONFIG_SND_DATE ".\n");
 381 #endif
 382         return 0;
 383 }
 384
 385 static void __exit alsa_sound_exit(void)
 386 {
 387         short controlnum;
 388
 389         for (controlnum = 0; controlnum < cards_limit; controlnum++) {
 390                 devfs_remove("snd/controlC%d", controlnum);
 391                 class_simple_device_remove(MKDEV(major, controlnum<<5));
 392         }
 393
 394 #ifdef CONFIG_SND_OSSEMUL
 395         snd_info_minor_unregister();
 396 #endif
 397         snd_info_done();
 398 #ifdef CONFIG_SND_DEBUG_MEMORY
 399         snd_memory_done();
 400 #endif
 401         if (unregister_chrdev(major, "alsa") != 0)
 402                 snd_printk(KERN_ERR "unable to unregister major device number %d\n", major);
 403         devfs_remove("snd");
 404 }
 405
 406 module_init(alsa_sound_init)
 407 module_exit(alsa_sound_exit)
 408
 409 #ifndef MODULE
 410
 411 /* format is: snd=major,cards_limit[,device_mode] */
 412
 413 static int __init alsa_sound_setup(char *str)
 414 {
 415         (void)(get_option(&str,&major) == 2 &&
 416                get_option(&str,&cards_limit) == 2);
 417 #ifdef CONFIG_DEVFS_FS
 418         (void)(get_option(&str,&device_mode) == 2);
 419 #endif
 420         return 1;
 421 }
 422
 423 __setup("snd=", alsa_sound_setup);
 424
 425 #endif /* ifndef MODULE */
 426
 427   /* sound.c */
 428 EXPORT_SYMBOL(snd_major);
 429 EXPORT_SYMBOL(snd_ecards_limit);
 430 #if defined(CONFIG_KMOD)
 431 EXPORT_SYMBOL(snd_request_card);
 432 #endif
 433 EXPORT_SYMBOL(snd_register_device);
 434 EXPORT_SYMBOL(snd_unregister_device);
 435 #if defined(CONFIG_SND_OSSEMUL)
 436 EXPORT_SYMBOL(snd_register_oss_device);
 437 EXPORT_SYMBOL(snd_unregister_oss_device);
 438 #endif
 439   /* memory.c */
 440 #ifdef CONFIG_SND_DEBUG_MEMORY
 441 EXPORT_SYMBOL(snd_hidden_kmalloc);
 442 EXPORT_SYMBOL(snd_hidden_kfree);
 443 EXPORT_SYMBOL(snd_hidden_vmalloc);
 444 EXPORT_SYMBOL(snd_hidden_vfree);
 445 EXPORT_SYMBOL(_snd_magic_kmalloc);
 446 EXPORT_SYMBOL(_snd_magic_kcalloc);
 447 EXPORT_SYMBOL(snd_magic_kfree);
 448 #endif
 449 EXPORT_SYMBOL(snd_kcalloc);
 450 EXPORT_SYMBOL(snd_kmalloc_strdup);
 451 EXPORT_SYMBOL(copy_to_user_fromio);
 452 EXPORT_SYMBOL(copy_from_user_toio);
 453   /* init.c */
 454 EXPORT_SYMBOL(snd_cards_count);
 455 EXPORT_SYMBOL(snd_cards);
 456 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
 457 EXPORT_SYMBOL(snd_mixer_oss_notify_callback);
 458 #endif
 459 EXPORT_SYMBOL(snd_card_new);
 460 EXPORT_SYMBOL(snd_card_disconnect);
 461 EXPORT_SYMBOL(snd_card_free);
 462 EXPORT_SYMBOL(snd_card_free_in_thread);
 463 EXPORT_SYMBOL(snd_card_register);
 464 EXPORT_SYMBOL(snd_component_add);
 465 EXPORT_SYMBOL(snd_card_file_add);
 466 EXPORT_SYMBOL(snd_card_file_remove);
 467 #ifdef CONFIG_PM
 468 EXPORT_SYMBOL(snd_power_wait);
 469 EXPORT_SYMBOL(snd_card_set_pm_callback);
 470 EXPORT_SYMBOL(snd_card_set_dev_pm_callback);
 471 #ifdef CONFIG_PCI
 472 EXPORT_SYMBOL(snd_card_pci_suspend);
 473 EXPORT_SYMBOL(snd_card_pci_resume);
 474 #endif
 475 #endif
 476   /* device.c */
 477 EXPORT_SYMBOL(snd_device_new);
 478 EXPORT_SYMBOL(snd_device_register);
 479 EXPORT_SYMBOL(snd_device_free);
 480 EXPORT_SYMBOL(snd_device_free_all);
 481   /* isadma.c */
 482 #ifdef CONFIG_ISA
 483 EXPORT_SYMBOL(snd_dma_program);
 484 EXPORT_SYMBOL(snd_dma_disable);
 485 EXPORT_SYMBOL(snd_dma_pointer);
 486 #endif
 487   /* info.c */
 488 #ifdef CONFIG_PROC_FS
 489 EXPORT_SYMBOL(snd_seq_root);
 490 EXPORT_SYMBOL(snd_create_proc_entry);
 491 EXPORT_SYMBOL(snd_remove_proc_entry);
 492 EXPORT_SYMBOL(snd_iprintf);
 493 EXPORT_SYMBOL(snd_info_get_line);
 494 EXPORT_SYMBOL(snd_info_get_str);
 495 EXPORT_SYMBOL(snd_info_create_module_entry);
 496 EXPORT_SYMBOL(snd_info_create_card_entry);
 497 EXPORT_SYMBOL(snd_info_free_entry);
 498 EXPORT_SYMBOL(snd_info_register);
 499 EXPORT_SYMBOL(snd_info_unregister);
 500 EXPORT_SYMBOL(snd_card_proc_new);
 501 #endif
 502   /* info_oss.c */
 503 #if defined(CONFIG_SND_OSSEMUL) && defined(CONFIG_PROC_FS)
 504 EXPORT_SYMBOL(snd_oss_info_register);
 505 #endif
 506   /* control.c */
 507 EXPORT_SYMBOL(snd_ctl_new);
 508 EXPORT_SYMBOL(snd_ctl_new1);
 509 EXPORT_SYMBOL(snd_ctl_free_one);
 510 EXPORT_SYMBOL(snd_ctl_add);
 511 EXPORT_SYMBOL(snd_ctl_remove);
 512 EXPORT_SYMBOL(snd_ctl_remove_id);
 513 EXPORT_SYMBOL(snd_ctl_rename_id);
 514 EXPORT_SYMBOL(snd_ctl_find_numid);
 515 EXPORT_SYMBOL(snd_ctl_find_id);
 516 EXPORT_SYMBOL(snd_ctl_notify);
 517 EXPORT_SYMBOL(snd_ctl_register_ioctl);
 518 EXPORT_SYMBOL(snd_ctl_unregister_ioctl);
 519   /* misc.c */
 520 EXPORT_SYMBOL(snd_task_name);
 521 #ifdef CONFIG_SND_VERBOSE_PRINTK
 522 EXPORT_SYMBOL(snd_verbose_printk);
 523 #endif
 524 #if defined(CONFIG_SND_DEBUG) && defined(CONFIG_SND_VERBOSE_PRINTK)
 525 EXPORT_SYMBOL(snd_verbose_printd);
 526 #endif
 527   /* wrappers */
 528 #ifdef CONFIG_SND_DEBUG_MEMORY
 529 EXPORT_SYMBOL(snd_wrapper_kmalloc);
 530 EXPORT_SYMBOL(snd_wrapper_kfree);
 531 EXPORT_SYMBOL(snd_wrapper_vmalloc);
 532 EXPORT_SYMBOL(snd_wrapper_vfree);
 533 #endif