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