Pileus Git - ~andy/linux/blob - 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
  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 list_head snd_minors_hash[SNDRV_CARDS];
  63
  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 static struct snd_minor *snd_minor_search(int minor)
 111 {
 112         struct list_head *list;
 113         struct snd_minor *mptr;
 114
 115         list_for_each(list, &snd_minors_hash[SNDRV_MINOR_CARD(minor)]) {
 116                 mptr = list_entry(list, struct snd_minor, list);
 117                 if (mptr->number == minor)
 118                         return mptr;
 119         }
 120         return NULL;
 121 }
 122
 123 static int snd_open(struct inode *inode, struct file *file)
 124 {
 125         int minor = iminor(inode);
 126         int card = SNDRV_MINOR_CARD(minor);
 127         int dev = SNDRV_MINOR_DEVICE(minor);
 128         struct snd_minor *mptr = NULL;
 129         struct file_operations *old_fops;
 130         int err = 0;
 131
 132         if (dev != SNDRV_MINOR_GLOBAL) {
 133                 if (snd_cards[card] == NULL) {
 134 #ifdef CONFIG_KMOD
 135                         snd_request_card(card);
 136                         if (snd_cards[card] == NULL)
 137 #endif
 138                                 return -ENODEV;
 139                 }
 140         } else {
 141 #ifdef CONFIG_KMOD
 142                 if ((mptr = snd_minor_search(minor)) == NULL)
 143                         snd_request_other(minor);
 144 #endif
 145         }
 146         if (mptr == NULL && (mptr = snd_minor_search(minor)) == NULL)
 147                 return -ENODEV;
 148         old_fops = file->f_op;
 149         file->f_op = fops_get(mptr->f_ops);
 150         if (file->f_op->open)
 151                 err = file->f_op->open(inode, file);
 152         if (err) {
 153                 fops_put(file->f_op);
 154                 file->f_op = fops_get(old_fops);
 155         }
 156         fops_put(old_fops);
 157         return err;
 158 }
 159
 160 static struct file_operations snd_fops =
 161 {
 162         .owner =        THIS_MODULE,
 163         .open =         snd_open
 164 };
 165
 166 static int snd_kernel_minor(int type, struct snd_card *card, int dev)
 167 {
 168         int minor;
 169
 170         switch (type) {
 171         case SNDRV_DEVICE_TYPE_SEQUENCER:
 172         case SNDRV_DEVICE_TYPE_TIMER:
 173                 minor = type;
 174                 break;
 175         case SNDRV_DEVICE_TYPE_CONTROL:
 176                 snd_assert(card != NULL, return -EINVAL);
 177                 minor = SNDRV_MINOR(card->number, type);
 178                 break;
 179         case SNDRV_DEVICE_TYPE_HWDEP:
 180         case SNDRV_DEVICE_TYPE_RAWMIDI:
 181         case SNDRV_DEVICE_TYPE_PCM_PLAYBACK:
 182         case SNDRV_DEVICE_TYPE_PCM_CAPTURE:
 183                 snd_assert(card != NULL, return -EINVAL);
 184                 minor = SNDRV_MINOR(card->number, type + dev);
 185                 break;
 186         default:
 187                 return -EINVAL;
 188         }
 189         snd_assert(minor >= 0 && minor < SNDRV_OS_MINORS, return -EINVAL);
 190         return minor;
 191 }
 192
 193 /**
 194  * snd_register_device - Register the ALSA device file for the card
 195  * @type: the device type, SNDRV_DEVICE_TYPE_XXX
 196  * @card: the card instance
 197  * @dev: the device index
 198  * @reg: the struct snd_minor record
 199  * @name: the device file name
 200  *
 201  * Registers an ALSA device file for the given card.
 202  * The operators have to be set in reg parameter.
 203  *
 204  * Retrurns zero if successful, or a negative error code on failure.
 205  */
 206 int snd_register_device(int type, struct snd_card *card, int dev, struct snd_minor * reg, const char *name)
 207 {
 208         int minor = snd_kernel_minor(type, card, dev);
 209         struct snd_minor *preg;
 210         struct device *device = NULL;
 211
 212         if (minor < 0)
 213                 return minor;
 214         snd_assert(name, return -EINVAL);
 215         preg = kmalloc(sizeof(struct snd_minor) + strlen(name) + 1, GFP_KERNEL);
 216         if (preg == NULL)
 217                 return -ENOMEM;
 218         *preg = *reg;
 219         preg->number = minor;
 220         preg->device = dev;
 221         strcpy(preg->name, name);
 222         down(&sound_mutex);
 223         if (snd_minor_search(minor)) {
 224                 up(&sound_mutex);
 225                 kfree(preg);
 226                 return -EBUSY;
 227         }
 228         list_add_tail(&preg->list, &snd_minors_hash[SNDRV_MINOR_CARD(minor)]);
 229         if (strncmp(name, "controlC", 8) || card->number >= cards_limit)
 230                 devfs_mk_cdev(MKDEV(major, minor), S_IFCHR | device_mode, "snd/%s", name);
 231         if (card)
 232                 device = card->dev;
 233         class_device_create(sound_class, NULL, MKDEV(major, minor), device, "%s", name);
 234
 235         up(&sound_mutex);
 236         return 0;
 237 }
 238
 239 /**
 240  * snd_unregister_device - unregister the device on the given card
 241  * @type: the device type, SNDRV_DEVICE_TYPE_XXX
 242  * @card: the card instance
 243  * @dev: the device index
 244  *
 245  * Unregisters the device file already registered via
 246  * snd_register_device().
 247  *
 248  * Returns zero if sucecessful, or a negative error code on failure
 249  */
 250 int snd_unregister_device(int type, struct snd_card *card, int dev)
 251 {
 252         int minor = snd_kernel_minor(type, card, dev);
 253         struct snd_minor *mptr;
 254
 255         if (minor < 0)
 256                 return minor;
 257         down(&sound_mutex);
 258         if ((mptr = snd_minor_search(minor)) == NULL) {
 259                 up(&sound_mutex);
 260                 return -EINVAL;
 261         }
 262
 263         if (strncmp(mptr->name, "controlC", 8) || card->number >= cards_limit) /* created in sound.c */
 264                 devfs_remove("snd/%s", mptr->name);
 265         class_device_destroy(sound_class, MKDEV(major, minor));
 266
 267         list_del(&mptr->list);
 268         up(&sound_mutex);
 269         kfree(mptr);
 270         return 0;
 271 }
 272
 273 /*
 274  *  INFO PART
 275  */
 276
 277 static struct snd_info_entry *snd_minor_info_entry = NULL;
 278
 279 static void snd_minor_info_read(struct snd_info_entry *entry, struct snd_info_buffer *buffer)
 280 {
 281         int card, device;
 282         struct list_head *list;
 283         struct snd_minor *mptr;
 284
 285         down(&sound_mutex);
 286         for (card = 0; card < SNDRV_CARDS; card++) {
 287                 list_for_each(list, &snd_minors_hash[card]) {
 288                         mptr = list_entry(list, struct snd_minor, list);
 289                         if (SNDRV_MINOR_DEVICE(mptr->number) != SNDRV_MINOR_GLOBAL) {
 290                                 if ((device = mptr->device) >= 0)
 291                                         snd_iprintf(buffer, "%3i: [%i-%2i]: %s\n", mptr->number, card, device, mptr->comment);
 292                                 else
 293                                         snd_iprintf(buffer, "%3i: [%i]   : %s\n", mptr->number, card, mptr->comment);
 294                         } else {
 295                                 snd_iprintf(buffer, "%3i:       : %s\n", mptr->number, mptr->comment);
 296                         }
 297                 }
 298         }
 299         up(&sound_mutex);
 300 }
 301
 302 int __init snd_minor_info_init(void)
 303 {
 304         struct snd_info_entry *entry;
 305
 306         entry = snd_info_create_module_entry(THIS_MODULE, "devices", NULL);
 307         if (entry) {
 308                 entry->c.text.read_size = PAGE_SIZE;
 309                 entry->c.text.read = snd_minor_info_read;
 310                 if (snd_info_register(entry) < 0) {
 311                         snd_info_free_entry(entry);
 312                         entry = NULL;
 313                 }
 314         }
 315         snd_minor_info_entry = entry;
 316         return 0;
 317 }
 318
 319 int __exit snd_minor_info_done(void)
 320 {
 321         if (snd_minor_info_entry)
 322                 snd_info_unregister(snd_minor_info_entry);
 323         return 0;
 324 }
 325
 326 /*
 327  *  INIT PART
 328  */
 329
 330 static int __init alsa_sound_init(void)
 331 {
 332         short controlnum;
 333         int err;
 334         int card;
 335
 336         snd_major = major;
 337         snd_ecards_limit = cards_limit;
 338         for (card = 0; card < SNDRV_CARDS; card++)
 339                 INIT_LIST_HEAD(&snd_minors_hash[card]);
 340         if ((err = snd_oss_init_module()) < 0)
 341                 return err;
 342         devfs_mk_dir("snd");
 343         if (register_chrdev(major, "alsa", &snd_fops)) {
 344                 snd_printk(KERN_ERR "unable to register native major device number %d\n", major);
 345                 devfs_remove("snd");
 346                 return -EIO;
 347         }
 348         if (snd_info_init() < 0) {
 349                 unregister_chrdev(major, "alsa");
 350                 devfs_remove("snd");
 351                 return -ENOMEM;
 352         }
 353         snd_info_minor_register();
 354         for (controlnum = 0; controlnum < cards_limit; controlnum++)
 355                 devfs_mk_cdev(MKDEV(major, controlnum<<5), S_IFCHR | device_mode, "snd/controlC%d", controlnum);
 356 #ifndef MODULE
 357         printk(KERN_INFO "Advanced Linux Sound Architecture Driver Version " CONFIG_SND_VERSION CONFIG_SND_DATE ".\n");
 358 #endif
 359         return 0;
 360 }
 361
 362 static void __exit alsa_sound_exit(void)
 363 {
 364         short controlnum;
 365
 366         for (controlnum = 0; controlnum < cards_limit; controlnum++)
 367                 devfs_remove("snd/controlC%d", controlnum);
 368
 369         snd_info_minor_unregister();
 370         snd_info_done();
 371         if (unregister_chrdev(major, "alsa") != 0)
 372                 snd_printk(KERN_ERR "unable to unregister major device number %d\n", major);
 373         devfs_remove("snd");
 374 }
 375
 376 module_init(alsa_sound_init)
 377 module_exit(alsa_sound_exit)
 378
 379   /* sound.c */
 380 EXPORT_SYMBOL(snd_major);
 381 EXPORT_SYMBOL(snd_ecards_limit);
 382 #if defined(CONFIG_KMOD)
 383 EXPORT_SYMBOL(snd_request_card);
 384 #endif
 385 EXPORT_SYMBOL(snd_register_device);
 386 EXPORT_SYMBOL(snd_unregister_device);
 387 #if defined(CONFIG_SND_OSSEMUL)
 388 EXPORT_SYMBOL(snd_register_oss_device);
 389 EXPORT_SYMBOL(snd_unregister_oss_device);
 390 #endif
 391   /* memory.c */
 392 EXPORT_SYMBOL(copy_to_user_fromio);
 393 EXPORT_SYMBOL(copy_from_user_toio);
 394   /* init.c */
 395 EXPORT_SYMBOL(snd_cards);
 396 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
 397 EXPORT_SYMBOL(snd_mixer_oss_notify_callback);
 398 #endif
 399 EXPORT_SYMBOL(snd_card_new);
 400 EXPORT_SYMBOL(snd_card_disconnect);
 401 EXPORT_SYMBOL(snd_card_free);
 402 EXPORT_SYMBOL(snd_card_free_in_thread);
 403 EXPORT_SYMBOL(snd_card_register);
 404 EXPORT_SYMBOL(snd_component_add);
 405 EXPORT_SYMBOL(snd_card_file_add);
 406 EXPORT_SYMBOL(snd_card_file_remove);
 407 #ifdef CONFIG_PM
 408 EXPORT_SYMBOL(snd_power_wait);
 409 #endif
 410   /* device.c */
 411 EXPORT_SYMBOL(snd_device_new);
 412 EXPORT_SYMBOL(snd_device_register);
 413 EXPORT_SYMBOL(snd_device_free);
 414   /* isadma.c */
 415 #ifdef CONFIG_ISA_DMA_API
 416 EXPORT_SYMBOL(snd_dma_program);
 417 EXPORT_SYMBOL(snd_dma_disable);
 418 EXPORT_SYMBOL(snd_dma_pointer);
 419 #endif
 420   /* info.c */
 421 #ifdef CONFIG_PROC_FS
 422 EXPORT_SYMBOL(snd_seq_root);
 423 EXPORT_SYMBOL(snd_iprintf);
 424 EXPORT_SYMBOL(snd_info_get_line);
 425 EXPORT_SYMBOL(snd_info_get_str);
 426 EXPORT_SYMBOL(snd_info_create_module_entry);
 427 EXPORT_SYMBOL(snd_info_create_card_entry);
 428 EXPORT_SYMBOL(snd_info_free_entry);
 429 EXPORT_SYMBOL(snd_info_register);
 430 EXPORT_SYMBOL(snd_info_unregister);
 431 EXPORT_SYMBOL(snd_card_proc_new);
 432 #endif
 433   /* info_oss.c */
 434 #if defined(CONFIG_SND_OSSEMUL) && defined(CONFIG_PROC_FS)
 435 EXPORT_SYMBOL(snd_oss_info_register);
 436 #endif
 437   /* control.c */
 438 EXPORT_SYMBOL(snd_ctl_new);
 439 EXPORT_SYMBOL(snd_ctl_new1);
 440 EXPORT_SYMBOL(snd_ctl_free_one);
 441 EXPORT_SYMBOL(snd_ctl_add);
 442 EXPORT_SYMBOL(snd_ctl_remove);
 443 EXPORT_SYMBOL(snd_ctl_remove_id);
 444 EXPORT_SYMBOL(snd_ctl_rename_id);
 445 EXPORT_SYMBOL(snd_ctl_find_numid);
 446 EXPORT_SYMBOL(snd_ctl_find_id);
 447 EXPORT_SYMBOL(snd_ctl_notify);
 448 EXPORT_SYMBOL(snd_ctl_register_ioctl);
 449 EXPORT_SYMBOL(snd_ctl_unregister_ioctl);
 450 #ifdef CONFIG_COMPAT
 451 EXPORT_SYMBOL(snd_ctl_register_ioctl_compat);
 452 EXPORT_SYMBOL(snd_ctl_unregister_ioctl_compat);
 453 #endif
 454 EXPORT_SYMBOL(snd_ctl_elem_read);
 455 EXPORT_SYMBOL(snd_ctl_elem_write);
 456   /* misc.c */
 457 EXPORT_SYMBOL(release_and_free_resource);
 458 #ifdef CONFIG_SND_VERBOSE_PRINTK
 459 EXPORT_SYMBOL(snd_verbose_printk);
 460 #endif
 461 #if defined(CONFIG_SND_DEBUG) && defined(CONFIG_SND_VERBOSE_PRINTK)
 462 EXPORT_SYMBOL(snd_verbose_printd);
 463 #endif