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