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