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