sound/core/control.c

   1 /*
   2  *  Routines for driver control interface
   3  *  Copyright (c) by Jaroslav Kysela <perex@perex.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 <linux/threads.h>
  23 #include <linux/interrupt.h>
  24 #include <linux/slab.h>
  25 #include <linux/vmalloc.h>
  26 #include <linux/time.h>
  27 #include <sound/core.h>
  28 #include <sound/minors.h>
  29 #include <sound/info.h>
  30 #include <sound/control.h>
  31
  32 /* max number of user-defined controls */
  33 #define MAX_USER_CONTROLS       32
  34 #define MAX_CONTROL_COUNT       1028
  35
  36 struct snd_kctl_ioctl {
  37         struct list_head list;          /* list of all ioctls */
  38         snd_kctl_ioctl_func_t fioctl;
  39 };
  40
  41 static DECLARE_RWSEM(snd_ioctl_rwsem);
  42 static LIST_HEAD(snd_control_ioctls);
  43 #ifdef CONFIG_COMPAT
  44 static LIST_HEAD(snd_control_compat_ioctls);
  45 #endif
  46
  47 static int snd_ctl_open(struct inode *inode, struct file *file)
  48 {
  49         unsigned long flags;
  50         struct snd_card *card;
  51         struct snd_ctl_file *ctl;
  52         int err;
  53
  54         err = nonseekable_open(inode, file);
  55         if (err < 0)
  56                 return err;
  57
  58         card = snd_lookup_minor_data(iminor(inode), SNDRV_DEVICE_TYPE_CONTROL);
  59         if (!card) {
  60                 err = -ENODEV;
  61                 goto __error1;
  62         }
  63         err = snd_card_file_add(card, file);
  64         if (err < 0) {
  65                 err = -ENODEV;
  66                 goto __error1;
  67         }
  68         if (!try_module_get(card->module)) {
  69                 err = -EFAULT;
  70                 goto __error2;
  71         }
  72         ctl = kzalloc(sizeof(*ctl), GFP_KERNEL);
  73         if (ctl == NULL) {
  74                 err = -ENOMEM;
  75                 goto __error;
  76         }
  77         INIT_LIST_HEAD(&ctl->events);
  78         init_waitqueue_head(&ctl->change_sleep);
  79         spin_lock_init(&ctl->read_lock);
  80         ctl->card = card;
  81         ctl->prefer_pcm_subdevice = -1;
  82         ctl->prefer_rawmidi_subdevice = -1;
  83         ctl->pid = get_pid(task_pid(current));
  84         file->private_data = ctl;
  85         write_lock_irqsave(&card->ctl_files_rwlock, flags);
  86         list_add_tail(&ctl->list, &card->ctl_files);
  87         write_unlock_irqrestore(&card->ctl_files_rwlock, flags);
  88         return 0;
  89
  90       __error:
  91         module_put(card->module);
  92       __error2:
  93         snd_card_file_remove(card, file);
  94       __error1:
  95         return err;
  96 }
  97
  98 static void snd_ctl_empty_read_queue(struct snd_ctl_file * ctl)
  99 {
 100         unsigned long flags;
 101         struct snd_kctl_event *cread;
 102
 103         spin_lock_irqsave(&ctl->read_lock, flags);
 104         while (!list_empty(&ctl->events)) {
 105                 cread = snd_kctl_event(ctl->events.next);
 106                 list_del(&cread->list);
 107                 kfree(cread);
 108         }
 109         spin_unlock_irqrestore(&ctl->read_lock, flags);
 110 }
 111
 112 static int snd_ctl_release(struct inode *inode, struct file *file)
 113 {
 114         unsigned long flags;
 115         struct snd_card *card;
 116         struct snd_ctl_file *ctl;
 117         struct snd_kcontrol *control;
 118         unsigned int idx;
 119
 120         ctl = file->private_data;
 121         file->private_data = NULL;
 122         card = ctl->card;
 123         write_lock_irqsave(&card->ctl_files_rwlock, flags);
 124         list_del(&ctl->list);
 125         write_unlock_irqrestore(&card->ctl_files_rwlock, flags);
 126         down_write(&card->controls_rwsem);
 127         list_for_each_entry(control, &card->controls, list)
 128                 for (idx = 0; idx < control->count; idx++)
 129                         if (control->vd[idx].owner == ctl)
 130                                 control->vd[idx].owner = NULL;
 131         up_write(&card->controls_rwsem);
 132         snd_ctl_empty_read_queue(ctl);
 133         put_pid(ctl->pid);
 134         kfree(ctl);
 135         module_put(card->module);
 136         snd_card_file_remove(card, file);
 137         return 0;
 138 }
 139
 140 void snd_ctl_notify(struct snd_card *card, unsigned int mask,
 141                     struct snd_ctl_elem_id *id)
 142 {
 143         unsigned long flags;
 144         struct snd_ctl_file *ctl;
 145         struct snd_kctl_event *ev;
 146
 147         if (snd_BUG_ON(!card || !id))
 148                 return;
 149         read_lock(&card->ctl_files_rwlock);
 150 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
 151         card->mixer_oss_change_count++;
 152 #endif
 153         list_for_each_entry(ctl, &card->ctl_files, list) {
 154                 if (!ctl->subscribed)
 155                         continue;
 156                 spin_lock_irqsave(&ctl->read_lock, flags);
 157                 list_for_each_entry(ev, &ctl->events, list) {
 158                         if (ev->id.numid == id->numid) {
 159                                 ev->mask |= mask;
 160                                 goto _found;
 161                         }
 162                 }
 163                 ev = kzalloc(sizeof(*ev), GFP_ATOMIC);
 164                 if (ev) {
 165                         ev->id = *id;
 166                         ev->mask = mask;
 167                         list_add_tail(&ev->list, &ctl->events);
 168                 } else {
 169                         snd_printk(KERN_ERR "No memory available to allocate event\n");
 170                 }
 171         _found:
 172                 wake_up(&ctl->change_sleep);
 173                 spin_unlock_irqrestore(&ctl->read_lock, flags);
 174                 kill_fasync(&ctl->fasync, SIGIO, POLL_IN);
 175         }
 176         read_unlock(&card->ctl_files_rwlock);
 177 }
 178
 179 EXPORT_SYMBOL(snd_ctl_notify);
 180
 181 /**
 182  * snd_ctl_new - create a control instance from the template
 183  * @control: the control template
 184  * @access: the default control access
 185  *
 186  * Allocates a new struct snd_kcontrol instance and copies the given template
 187  * to the new instance. It does not copy volatile data (access).
 188  *
 189  * Returns the pointer of the new instance, or NULL on failure.
 190  */
 191 static struct snd_kcontrol *snd_ctl_new(struct snd_kcontrol *control,
 192                                         unsigned int access)
 193 {
 194         struct snd_kcontrol *kctl;
 195         unsigned int idx;
 196
 197         if (snd_BUG_ON(!control || !control->count))
 198                 return NULL;
 199
 200         if (control->count > MAX_CONTROL_COUNT)
 201                 return NULL;
 202
 203         kctl = kzalloc(sizeof(*kctl) + sizeof(struct snd_kcontrol_volatile) * control->count, GFP_KERNEL);
 204         if (kctl == NULL) {
 205                 snd_printk(KERN_ERR "Cannot allocate control instance\n");
 206                 return NULL;
 207         }
 208         *kctl = *control;
 209         for (idx = 0; idx < kctl->count; idx++)
 210                 kctl->vd[idx].access = access;
 211         return kctl;
 212 }
 213
 214 /**
 215  * snd_ctl_new1 - create a control instance from the template
 216  * @ncontrol: the initialization record
 217  * @private_data: the private data to set
 218  *
 219  * Allocates a new struct snd_kcontrol instance and initialize from the given
 220  * template.  When the access field of ncontrol is 0, it's assumed as
 221  * READWRITE access. When the count field is 0, it's assumes as one.
 222  *
 223  * Returns the pointer of the newly generated instance, or NULL on failure.
 224  */
 225 struct snd_kcontrol *snd_ctl_new1(const struct snd_kcontrol_new *ncontrol,
 226                                   void *private_data)
 227 {
 228         struct snd_kcontrol kctl;
 229         unsigned int access;
 230
 231         if (snd_BUG_ON(!ncontrol || !ncontrol->info))
 232                 return NULL;
 233         memset(&kctl, 0, sizeof(kctl));
 234         kctl.id.iface = ncontrol->iface;
 235         kctl.id.device = ncontrol->device;
 236         kctl.id.subdevice = ncontrol->subdevice;
 237         if (ncontrol->name) {
 238                 strlcpy(kctl.id.name, ncontrol->name, sizeof(kctl.id.name));
 239                 if (strcmp(ncontrol->name, kctl.id.name) != 0)
 240                         snd_printk(KERN_WARNING
 241                                    "Control name '%s' truncated to '%s'\n",
 242                                    ncontrol->name, kctl.id.name);
 243         }
 244         kctl.id.index = ncontrol->index;
 245         kctl.count = ncontrol->count ? ncontrol->count : 1;
 246         access = ncontrol->access == 0 ? SNDRV_CTL_ELEM_ACCESS_READWRITE :
 247                  (ncontrol->access & (SNDRV_CTL_ELEM_ACCESS_READWRITE|
 248                                       SNDRV_CTL_ELEM_ACCESS_INACTIVE|
 249                                       SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE|
 250                                       SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND|
 251                                       SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK));
 252         kctl.info = ncontrol->info;
 253         kctl.get = ncontrol->get;
 254         kctl.put = ncontrol->put;
 255         kctl.tlv.p = ncontrol->tlv.p;
 256         kctl.private_value = ncontrol->private_value;
 257         kctl.private_data = private_data;
 258         return snd_ctl_new(&kctl, access);
 259 }
 260
 261 EXPORT_SYMBOL(snd_ctl_new1);
 262
 263 /**
 264  * snd_ctl_free_one - release the control instance
 265  * @kcontrol: the control instance
 266  *
 267  * Releases the control instance created via snd_ctl_new()
 268  * or snd_ctl_new1().
 269  * Don't call this after the control was added to the card.
 270  */
 271 void snd_ctl_free_one(struct snd_kcontrol *kcontrol)
 272 {
 273         if (kcontrol) {
 274                 if (kcontrol->private_free)
 275                         kcontrol->private_free(kcontrol);
 276                 kfree(kcontrol);
 277         }
 278 }
 279
 280 EXPORT_SYMBOL(snd_ctl_free_one);
 281
 282 static unsigned int snd_ctl_hole_check(struct snd_card *card,
 283                                        unsigned int count)
 284 {
 285         struct snd_kcontrol *kctl;
 286
 287         list_for_each_entry(kctl, &card->controls, list) {
 288                 if ((kctl->id.numid <= card->last_numid &&
 289                      kctl->id.numid + kctl->count > card->last_numid) ||
 290                     (kctl->id.numid <= card->last_numid + count - 1 &&
 291                      kctl->id.numid + kctl->count > card->last_numid + count - 1))
 292                         return card->last_numid = kctl->id.numid + kctl->count - 1;
 293         }
 294         return card->last_numid;
 295 }
 296
 297 static int snd_ctl_find_hole(struct snd_card *card, unsigned int count)
 298 {
 299         unsigned int last_numid, iter = 100000;
 300
 301         last_numid = card->last_numid;
 302         while (last_numid != snd_ctl_hole_check(card, count)) {
 303                 if (--iter == 0) {
 304                         /* this situation is very unlikely */
 305                         snd_printk(KERN_ERR "unable to allocate new control numid\n");
 306                         return -ENOMEM;
 307                 }
 308                 last_numid = card->last_numid;
 309         }
 310         return 0;
 311 }
 312
 313 /**
 314  * snd_ctl_add - add the control instance to the card
 315  * @card: the card instance
 316  * @kcontrol: the control instance to add
 317  *
 318  * Adds the control instance created via snd_ctl_new() or
 319  * snd_ctl_new1() to the given card. Assigns also an unique
 320  * numid used for fast search.
 321  *
 322  * Returns zero if successful, or a negative error code on failure.
 323  *
 324  * It frees automatically the control which cannot be added.
 325  */
 326 int snd_ctl_add(struct snd_card *card, struct snd_kcontrol *kcontrol)
 327 {
 328         struct snd_ctl_elem_id id;
 329         unsigned int idx;
 330         int err = -EINVAL;
 331
 332         if (! kcontrol)
 333                 return err;
 334         if (snd_BUG_ON(!card || !kcontrol->info))
 335                 goto error;
 336         id = kcontrol->id;
 337         down_write(&card->controls_rwsem);
 338         if (snd_ctl_find_id(card, &id)) {
 339                 up_write(&card->controls_rwsem);
 340                 snd_printd(KERN_ERR "control %i:%i:%i:%s:%i is already present\n",
 341                                         id.iface,
 342                                         id.device,
 343                                         id.subdevice,
 344                                         id.name,
 345                                         id.index);
 346                 err = -EBUSY;
 347                 goto error;
 348         }
 349         if (snd_ctl_find_hole(card, kcontrol->count) < 0) {
 350                 up_write(&card->controls_rwsem);
 351                 err = -ENOMEM;
 352                 goto error;
 353         }
 354         list_add_tail(&kcontrol->list, &card->controls);
 355         card->controls_count += kcontrol->count;
 356         kcontrol->id.numid = card->last_numid + 1;
 357         card->last_numid += kcontrol->count;
 358         up_write(&card->controls_rwsem);
 359         for (idx = 0; idx < kcontrol->count; idx++, id.index++, id.numid++)
 360                 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_ADD, &id);
 361         return 0;
 362
 363  error:
 364         snd_ctl_free_one(kcontrol);
 365         return err;
 366 }
 367
 368 EXPORT_SYMBOL(snd_ctl_add);
 369
 370 /**
 371  * snd_ctl_remove - remove the control from the card and release it
 372  * @card: the card instance
 373  * @kcontrol: the control instance to remove
 374  *
 375  * Removes the control from the card and then releases the instance.
 376  * You don't need to call snd_ctl_free_one(). You must be in
 377  * the write lock - down_write(&card->controls_rwsem).
 378  *
 379  * Returns 0 if successful, or a negative error code on failure.
 380  */
 381 int snd_ctl_remove(struct snd_card *card, struct snd_kcontrol *kcontrol)
 382 {
 383         struct snd_ctl_elem_id id;
 384         unsigned int idx;
 385
 386         if (snd_BUG_ON(!card || !kcontrol))
 387                 return -EINVAL;
 388         list_del(&kcontrol->list);
 389         card->controls_count -= kcontrol->count;
 390         id = kcontrol->id;
 391         for (idx = 0; idx < kcontrol->count; idx++, id.index++, id.numid++)
 392                 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_REMOVE, &id);
 393         snd_ctl_free_one(kcontrol);
 394         return 0;
 395 }
 396
 397 EXPORT_SYMBOL(snd_ctl_remove);
 398
 399 /**
 400  * snd_ctl_remove_id - remove the control of the given id and release it
 401  * @card: the card instance
 402  * @id: the control id to remove
 403  *
 404  * Finds the control instance with the given id, removes it from the
 405  * card list and releases it.
 406  *
 407  * Returns 0 if successful, or a negative error code on failure.
 408  */
 409 int snd_ctl_remove_id(struct snd_card *card, struct snd_ctl_elem_id *id)
 410 {
 411         struct snd_kcontrol *kctl;
 412         int ret;
 413
 414         down_write(&card->controls_rwsem);
 415         kctl = snd_ctl_find_id(card, id);
 416         if (kctl == NULL) {
 417                 up_write(&card->controls_rwsem);
 418                 return -ENOENT;
 419         }
 420         ret = snd_ctl_remove(card, kctl);
 421         up_write(&card->controls_rwsem);
 422         return ret;
 423 }
 424
 425 EXPORT_SYMBOL(snd_ctl_remove_id);
 426
 427 /**
 428  * snd_ctl_remove_user_ctl - remove and release the unlocked user control
 429  * @file: active control handle
 430  * @id: the control id to remove
 431  *
 432  * Finds the control instance with the given id, removes it from the
 433  * card list and releases it.
 434  *
 435  * Returns 0 if successful, or a negative error code on failure.
 436  */
 437 static int snd_ctl_remove_user_ctl(struct snd_ctl_file * file,
 438                                    struct snd_ctl_elem_id *id)
 439 {
 440         struct snd_card *card = file->card;
 441         struct snd_kcontrol *kctl;
 442         int idx, ret;
 443
 444         down_write(&card->controls_rwsem);
 445         kctl = snd_ctl_find_id(card, id);
 446         if (kctl == NULL) {
 447                 ret = -ENOENT;
 448                 goto error;
 449         }
 450         if (!(kctl->vd[0].access & SNDRV_CTL_ELEM_ACCESS_USER)) {
 451                 ret = -EINVAL;
 452                 goto error;
 453         }
 454         for (idx = 0; idx < kctl->count; idx++)
 455                 if (kctl->vd[idx].owner != NULL && kctl->vd[idx].owner != file) {
 456                         ret = -EBUSY;
 457                         goto error;
 458                 }
 459         ret = snd_ctl_remove(card, kctl);
 460         if (ret < 0)
 461                 goto error;
 462         card->user_ctl_count--;
 463 error:
 464         up_write(&card->controls_rwsem);
 465         return ret;
 466 }
 467
 468 /**
 469  * snd_ctl_activate_id - activate/inactivate the control of the given id
 470  * @card: the card instance
 471  * @id: the control id to activate/inactivate
 472  * @active: non-zero to activate
 473  *
 474  * Finds the control instance with the given id, and activate or
 475  * inactivate the control together with notification, if changed.
 476  *
 477  * Returns 0 if unchanged, 1 if changed, or a negative error code on failure.
 478  */
 479 int snd_ctl_activate_id(struct snd_card *card, struct snd_ctl_elem_id *id,
 480                         int active)
 481 {
 482         struct snd_kcontrol *kctl;
 483         struct snd_kcontrol_volatile *vd;
 484         unsigned int index_offset;
 485         int ret;
 486
 487         down_write(&card->controls_rwsem);
 488         kctl = snd_ctl_find_id(card, id);
 489         if (kctl == NULL) {
 490                 ret = -ENOENT;
 491                 goto unlock;
 492         }
 493         index_offset = snd_ctl_get_ioff(kctl, &kctl->id);
 494         vd = &kctl->vd[index_offset];
 495         ret = 0;
 496         if (active) {
 497                 if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_INACTIVE))
 498                         goto unlock;
 499                 vd->access &= ~SNDRV_CTL_ELEM_ACCESS_INACTIVE;
 500         } else {
 501                 if (vd->access & SNDRV_CTL_ELEM_ACCESS_INACTIVE)
 502                         goto unlock;
 503                 vd->access |= SNDRV_CTL_ELEM_ACCESS_INACTIVE;
 504         }
 505         ret = 1;
 506  unlock:
 507         up_write(&card->controls_rwsem);
 508         if (ret > 0)
 509                 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_INFO, id);
 510         return ret;
 511 }
 512 EXPORT_SYMBOL_GPL(snd_ctl_activate_id);
 513
 514 /**
 515  * snd_ctl_rename_id - replace the id of a control on the card
 516  * @card: the card instance
 517  * @src_id: the old id
 518  * @dst_id: the new id
 519  *
 520  * Finds the control with the old id from the card, and replaces the
 521  * id with the new one.
 522  *
 523  * Returns zero if successful, or a negative error code on failure.
 524  */
 525 int snd_ctl_rename_id(struct snd_card *card, struct snd_ctl_elem_id *src_id,
 526                       struct snd_ctl_elem_id *dst_id)
 527 {
 528         struct snd_kcontrol *kctl;
 529
 530         down_write(&card->controls_rwsem);
 531         kctl = snd_ctl_find_id(card, src_id);
 532         if (kctl == NULL) {
 533                 up_write(&card->controls_rwsem);
 534                 return -ENOENT;
 535         }
 536         kctl->id = *dst_id;
 537         kctl->id.numid = card->last_numid + 1;
 538         card->last_numid += kctl->count;
 539         up_write(&card->controls_rwsem);
 540         return 0;
 541 }
 542
 543 EXPORT_SYMBOL(snd_ctl_rename_id);
 544
 545 /**
 546  * snd_ctl_find_numid - find the control instance with the given number-id
 547  * @card: the card instance
 548  * @numid: the number-id to search
 549  *
 550  * Finds the control instance with the given number-id from the card.
 551  *
 552  * Returns the pointer of the instance if found, or NULL if not.
 553  *
 554  * The caller must down card->controls_rwsem before calling this function
 555  * (if the race condition can happen).
 556  */
 557 struct snd_kcontrol *snd_ctl_find_numid(struct snd_card *card, unsigned int numid)
 558 {
 559         struct snd_kcontrol *kctl;
 560
 561         if (snd_BUG_ON(!card || !numid))
 562                 return NULL;
 563         list_for_each_entry(kctl, &card->controls, list) {
 564                 if (kctl->id.numid <= numid && kctl->id.numid + kctl->count > numid)
 565                         return kctl;
 566         }
 567         return NULL;
 568 }
 569
 570 EXPORT_SYMBOL(snd_ctl_find_numid);
 571
 572 /**
 573  * snd_ctl_find_id - find the control instance with the given id
 574  * @card: the card instance
 575  * @id: the id to search
 576  *
 577  * Finds the control instance with the given id from the card.
 578  *
 579  * Returns the pointer of the instance if found, or NULL if not.
 580  *
 581  * The caller must down card->controls_rwsem before calling this function
 582  * (if the race condition can happen).
 583  */
 584 struct snd_kcontrol *snd_ctl_find_id(struct snd_card *card,
 585                                      struct snd_ctl_elem_id *id)
 586 {
 587         struct snd_kcontrol *kctl;
 588
 589         if (snd_BUG_ON(!card || !id))
 590                 return NULL;
 591         if (id->numid != 0)
 592                 return snd_ctl_find_numid(card, id->numid);
 593         list_for_each_entry(kctl, &card->controls, list) {
 594                 if (kctl->id.iface != id->iface)
 595                         continue;
 596                 if (kctl->id.device != id->device)
 597                         continue;
 598                 if (kctl->id.subdevice != id->subdevice)
 599                         continue;
 600                 if (strncmp(kctl->id.name, id->name, sizeof(kctl->id.name)))
 601                         continue;
 602                 if (kctl->id.index > id->index)
 603                         continue;
 604                 if (kctl->id.index + kctl->count <= id->index)
 605                         continue;
 606                 return kctl;
 607         }
 608         return NULL;
 609 }
 610
 611 EXPORT_SYMBOL(snd_ctl_find_id);
 612
 613 static int snd_ctl_card_info(struct snd_card *card, struct snd_ctl_file * ctl,
 614                              unsigned int cmd, void __user *arg)
 615 {
 616         struct snd_ctl_card_info *info;
 617
 618         info = kzalloc(sizeof(*info), GFP_KERNEL);
 619         if (! info)
 620                 return -ENOMEM;
 621         down_read(&snd_ioctl_rwsem);
 622         info->card = card->number;
 623         strlcpy(info->id, card->id, sizeof(info->id));
 624         strlcpy(info->driver, card->driver, sizeof(info->driver));
 625         strlcpy(info->name, card->shortname, sizeof(info->name));
 626         strlcpy(info->longname, card->longname, sizeof(info->longname));
 627         strlcpy(info->mixername, card->mixername, sizeof(info->mixername));
 628         strlcpy(info->components, card->components, sizeof(info->components));
 629         up_read(&snd_ioctl_rwsem);
 630         if (copy_to_user(arg, info, sizeof(struct snd_ctl_card_info))) {
 631                 kfree(info);
 632                 return -EFAULT;
 633         }
 634         kfree(info);
 635         return 0;
 636 }
 637
 638 static int snd_ctl_elem_list(struct snd_card *card,
 639                              struct snd_ctl_elem_list __user *_list)
 640 {
 641         struct list_head *plist;
 642         struct snd_ctl_elem_list list;
 643         struct snd_kcontrol *kctl;
 644         struct snd_ctl_elem_id *dst, *id;
 645         unsigned int offset, space, first, jidx;
 646
 647         if (copy_from_user(&list, _list, sizeof(list)))
 648                 return -EFAULT;
 649         offset = list.offset;
 650         space = list.space;
 651         first = 0;
 652         /* try limit maximum space */
 653         if (space > 16384)
 654                 return -ENOMEM;
 655         if (space > 0) {
 656                 /* allocate temporary buffer for atomic operation */
 657                 dst = vmalloc(space * sizeof(struct snd_ctl_elem_id));
 658                 if (dst == NULL)
 659                         return -ENOMEM;
 660                 down_read(&card->controls_rwsem);
 661                 list.count = card->controls_count;
 662                 plist = card->controls.next;
 663                 while (plist != &card->controls) {
 664                         if (offset == 0)
 665                                 break;
 666                         kctl = snd_kcontrol(plist);
 667                         if (offset < kctl->count)
 668                                 break;
 669                         offset -= kctl->count;
 670                         plist = plist->next;
 671                 }
 672                 list.used = 0;
 673                 id = dst;
 674                 while (space > 0 && plist != &card->controls) {
 675                         kctl = snd_kcontrol(plist);
 676                         for (jidx = offset; space > 0 && jidx < kctl->count; jidx++) {
 677                                 snd_ctl_build_ioff(id, kctl, jidx);
 678                                 id++;
 679                                 space--;
 680                                 list.used++;
 681                         }
 682                         plist = plist->next;
 683                         offset = 0;
 684                 }
 685                 up_read(&card->controls_rwsem);
 686                 if (list.used > 0 &&
 687                     copy_to_user(list.pids, dst,
 688                                  list.used * sizeof(struct snd_ctl_elem_id))) {
 689                         vfree(dst);
 690                         return -EFAULT;
 691                 }
 692                 vfree(dst);
 693         } else {
 694                 down_read(&card->controls_rwsem);
 695                 list.count = card->controls_count;
 696                 up_read(&card->controls_rwsem);
 697         }
 698         if (copy_to_user(_list, &list, sizeof(list)))
 699                 return -EFAULT;
 700         return 0;
 701 }
 702
 703 static int snd_ctl_elem_info(struct snd_ctl_file *ctl,
 704                              struct snd_ctl_elem_info *info)
 705 {
 706         struct snd_card *card = ctl->card;
 707         struct snd_kcontrol *kctl;
 708         struct snd_kcontrol_volatile *vd;
 709         unsigned int index_offset;
 710         int result;
 711
 712         down_read(&card->controls_rwsem);
 713         kctl = snd_ctl_find_id(card, &info->id);
 714         if (kctl == NULL) {
 715                 up_read(&card->controls_rwsem);
 716                 return -ENOENT;
 717         }
 718 #ifdef CONFIG_SND_DEBUG
 719         info->access = 0;
 720 #endif
 721         result = kctl->info(kctl, info);
 722         if (result >= 0) {
 723                 snd_BUG_ON(info->access);
 724                 index_offset = snd_ctl_get_ioff(kctl, &info->id);
 725                 vd = &kctl->vd[index_offset];
 726                 snd_ctl_build_ioff(&info->id, kctl, index_offset);
 727                 info->access = vd->access;
 728                 if (vd->owner) {
 729                         info->access |= SNDRV_CTL_ELEM_ACCESS_LOCK;
 730                         if (vd->owner == ctl)
 731                                 info->access |= SNDRV_CTL_ELEM_ACCESS_OWNER;
 732                         info->owner = pid_vnr(vd->owner->pid);
 733                 } else {
 734                         info->owner = -1;
 735                 }
 736         }
 737         up_read(&card->controls_rwsem);
 738         return result;
 739 }
 740
 741 static int snd_ctl_elem_info_user(struct snd_ctl_file *ctl,
 742                                   struct snd_ctl_elem_info __user *_info)
 743 {
 744         struct snd_ctl_elem_info info;
 745         int result;
 746
 747         if (copy_from_user(&info, _info, sizeof(info)))
 748                 return -EFAULT;
 749         snd_power_lock(ctl->card);
 750         result = snd_power_wait(ctl->card, SNDRV_CTL_POWER_D0);
 751         if (result >= 0)
 752                 result = snd_ctl_elem_info(ctl, &info);
 753         snd_power_unlock(ctl->card);
 754         if (result >= 0)
 755                 if (copy_to_user(_info, &info, sizeof(info)))
 756                         return -EFAULT;
 757         return result;
 758 }
 759
 760 static int snd_ctl_elem_read(struct snd_card *card,
 761                              struct snd_ctl_elem_value *control)
 762 {
 763         struct snd_kcontrol *kctl;
 764         struct snd_kcontrol_volatile *vd;
 765         unsigned int index_offset;
 766         int result;
 767
 768         down_read(&card->controls_rwsem);
 769         kctl = snd_ctl_find_id(card, &control->id);
 770         if (kctl == NULL) {
 771                 result = -ENOENT;
 772         } else {
 773                 index_offset = snd_ctl_get_ioff(kctl, &control->id);
 774                 vd = &kctl->vd[index_offset];
 775                 if ((vd->access & SNDRV_CTL_ELEM_ACCESS_READ) &&
 776                     kctl->get != NULL) {
 777                         snd_ctl_build_ioff(&control->id, kctl, index_offset);
 778                         result = kctl->get(kctl, control);
 779                 } else
 780                         result = -EPERM;
 781         }
 782         up_read(&card->controls_rwsem);
 783         return result;
 784 }
 785
 786 static int snd_ctl_elem_read_user(struct snd_card *card,
 787                                   struct snd_ctl_elem_value __user *_control)
 788 {
 789         struct snd_ctl_elem_value *control;
 790         int result;
 791
 792         control = memdup_user(_control, sizeof(*control));
 793         if (IS_ERR(control))
 794                 return PTR_ERR(control);
 795
 796         snd_power_lock(card);
 797         result = snd_power_wait(card, SNDRV_CTL_POWER_D0);
 798         if (result >= 0)
 799                 result = snd_ctl_elem_read(card, control);
 800         snd_power_unlock(card);
 801         if (result >= 0)
 802                 if (copy_to_user(_control, control, sizeof(*control)))
 803                         result = -EFAULT;
 804         kfree(control);
 805         return result;
 806 }
 807
 808 static int snd_ctl_elem_write(struct snd_card *card, struct snd_ctl_file *file,
 809                               struct snd_ctl_elem_value *control)
 810 {
 811         struct snd_kcontrol *kctl;
 812         struct snd_kcontrol_volatile *vd;
 813         unsigned int index_offset;
 814         int result;
 815
 816         down_read(&card->controls_rwsem);
 817         kctl = snd_ctl_find_id(card, &control->id);
 818         if (kctl == NULL) {
 819                 result = -ENOENT;
 820         } else {
 821                 index_offset = snd_ctl_get_ioff(kctl, &control->id);
 822                 vd = &kctl->vd[index_offset];
 823                 if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_WRITE) ||
 824                     kctl->put == NULL ||
 825                     (file && vd->owner && vd->owner != file)) {
 826                         result = -EPERM;
 827                 } else {
 828                         snd_ctl_build_ioff(&control->id, kctl, index_offset);
 829                         result = kctl->put(kctl, control);
 830                 }
 831                 if (result > 0) {
 832                         up_read(&card->controls_rwsem);
 833                         snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
 834                                        &control->id);
 835                         return 0;
 836                 }
 837         }
 838         up_read(&card->controls_rwsem);
 839         return result;
 840 }
 841
 842 static int snd_ctl_elem_write_user(struct snd_ctl_file *file,
 843                                    struct snd_ctl_elem_value __user *_control)
 844 {
 845         struct snd_ctl_elem_value *control;
 846         struct snd_card *card;
 847         int result;
 848
 849         control = memdup_user(_control, sizeof(*control));
 850         if (IS_ERR(control))
 851                 return PTR_ERR(control);
 852
 853         card = file->card;
 854         snd_power_lock(card);
 855         result = snd_power_wait(card, SNDRV_CTL_POWER_D0);
 856         if (result >= 0)
 857                 result = snd_ctl_elem_write(card, file, control);
 858         snd_power_unlock(card);
 859         if (result >= 0)
 860                 if (copy_to_user(_control, control, sizeof(*control)))
 861                         result = -EFAULT;
 862         kfree(control);
 863         return result;
 864 }
 865
 866 static int snd_ctl_elem_lock(struct snd_ctl_file *file,
 867                              struct snd_ctl_elem_id __user *_id)
 868 {
 869         struct snd_card *card = file->card;
 870         struct snd_ctl_elem_id id;
 871         struct snd_kcontrol *kctl;
 872         struct snd_kcontrol_volatile *vd;
 873         int result;
 874
 875         if (copy_from_user(&id, _id, sizeof(id)))
 876                 return -EFAULT;
 877         down_write(&card->controls_rwsem);
 878         kctl = snd_ctl_find_id(card, &id);
 879         if (kctl == NULL) {
 880                 result = -ENOENT;
 881         } else {
 882                 vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)];
 883                 if (vd->owner != NULL)
 884                         result = -EBUSY;
 885                 else {
 886                         vd->owner = file;
 887                         result = 0;
 888                 }
 889         }
 890         up_write(&card->controls_rwsem);
 891         return result;
 892 }
 893
 894 static int snd_ctl_elem_unlock(struct snd_ctl_file *file,
 895                                struct snd_ctl_elem_id __user *_id)
 896 {
 897         struct snd_card *card = file->card;
 898         struct snd_ctl_elem_id id;
 899         struct snd_kcontrol *kctl;
 900         struct snd_kcontrol_volatile *vd;
 901         int result;
 902
 903         if (copy_from_user(&id, _id, sizeof(id)))
 904                 return -EFAULT;
 905         down_write(&card->controls_rwsem);
 906         kctl = snd_ctl_find_id(card, &id);
 907         if (kctl == NULL) {
 908                 result = -ENOENT;
 909         } else {
 910                 vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)];
 911                 if (vd->owner == NULL)
 912                         result = -EINVAL;
 913                 else if (vd->owner != file)
 914                         result = -EPERM;
 915                 else {
 916                         vd->owner = NULL;
 917                         result = 0;
 918                 }
 919         }
 920         up_write(&card->controls_rwsem);
 921         return result;
 922 }
 923
 924 struct user_element {
 925         struct snd_ctl_elem_info info;
 926         void *elem_data;                /* element data */
 927         unsigned long elem_data_size;   /* size of element data in bytes */
 928         void *tlv_data;                 /* TLV data */
 929         unsigned long tlv_data_size;    /* TLV data size */
 930         void *priv_data;                /* private data (like strings for enumerated type) */
 931         unsigned long priv_data_size;   /* size of private data in bytes */
 932 };
 933
 934 static int snd_ctl_elem_user_info(struct snd_kcontrol *kcontrol,
 935                                   struct snd_ctl_elem_info *uinfo)
 936 {
 937         struct user_element *ue = kcontrol->private_data;
 938
 939         *uinfo = ue->info;
 940         return 0;
 941 }
 942
 943 static int snd_ctl_elem_user_get(struct snd_kcontrol *kcontrol,
 944                                  struct snd_ctl_elem_value *ucontrol)
 945 {
 946         struct user_element *ue = kcontrol->private_data;
 947
 948         memcpy(&ucontrol->value, ue->elem_data, ue->elem_data_size);
 949         return 0;
 950 }
 951
 952 static int snd_ctl_elem_user_put(struct snd_kcontrol *kcontrol,
 953                                  struct snd_ctl_elem_value *ucontrol)
 954 {
 955         int change;
 956         struct user_element *ue = kcontrol->private_data;
 957
 958         change = memcmp(&ucontrol->value, ue->elem_data, ue->elem_data_size) != 0;
 959         if (change)
 960                 memcpy(ue->elem_data, &ucontrol->value, ue->elem_data_size);
 961         return change;
 962 }
 963
 964 static int snd_ctl_elem_user_tlv(struct snd_kcontrol *kcontrol,
 965                                  int op_flag,
 966                                  unsigned int size,
 967                                  unsigned int __user *tlv)
 968 {
 969         struct user_element *ue = kcontrol->private_data;
 970         int change = 0;
 971         void *new_data;
 972
 973         if (op_flag > 0) {
 974                 if (size > 1024 * 128)  /* sane value */
 975                         return -EINVAL;
 976
 977                 new_data = memdup_user(tlv, size);
 978                 if (IS_ERR(new_data))
 979                         return PTR_ERR(new_data);
 980                 change = ue->tlv_data_size != size;
 981                 if (!change)
 982                         change = memcmp(ue->tlv_data, new_data, size);
 983                 kfree(ue->tlv_data);
 984                 ue->tlv_data = new_data;
 985                 ue->tlv_data_size = size;
 986         } else {
 987                 if (! ue->tlv_data_size || ! ue->tlv_data)
 988                         return -ENXIO;
 989                 if (size < ue->tlv_data_size)
 990                         return -ENOSPC;
 991                 if (copy_to_user(tlv, ue->tlv_data, ue->tlv_data_size))
 992                         return -EFAULT;
 993         }
 994         return change;
 995 }
 996
 997 static void snd_ctl_elem_user_free(struct snd_kcontrol *kcontrol)
 998 {
 999         struct user_element *ue = kcontrol->private_data;
1000         if (ue->tlv_data)
1001                 kfree(ue->tlv_data);
1002         kfree(ue);
1003 }
1004
1005 static int snd_ctl_elem_add(struct snd_ctl_file *file,
1006                             struct snd_ctl_elem_info *info, int replace)
1007 {
1008         struct snd_card *card = file->card;
1009         struct snd_kcontrol kctl, *_kctl;
1010         unsigned int access;
1011         long private_size;
1012         struct user_element *ue;
1013         int idx, err;
1014
1015         if (card->user_ctl_count >= MAX_USER_CONTROLS)
1016                 return -ENOMEM;
1017         if (info->count < 1)
1018                 return -EINVAL;
1019         access = info->access == 0 ? SNDRV_CTL_ELEM_ACCESS_READWRITE :
1020                 (info->access & (SNDRV_CTL_ELEM_ACCESS_READWRITE|
1021                                  SNDRV_CTL_ELEM_ACCESS_INACTIVE|
1022                                  SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE));
1023         info->id.numid = 0;
1024         memset(&kctl, 0, sizeof(kctl));
1025         down_write(&card->controls_rwsem);
1026         _kctl = snd_ctl_find_id(card, &info->id);
1027         err = 0;
1028         if (_kctl) {
1029                 if (replace)
1030                         err = snd_ctl_remove(card, _kctl);
1031                 else
1032                         err = -EBUSY;
1033         } else {
1034                 if (replace)
1035                         err = -ENOENT;
1036         }
1037         up_write(&card->controls_rwsem);
1038         if (err < 0)
1039                 return err;
1040         memcpy(&kctl.id, &info->id, sizeof(info->id));
1041         kctl.count = info->owner ? info->owner : 1;
1042         access |= SNDRV_CTL_ELEM_ACCESS_USER;
1043         kctl.info = snd_ctl_elem_user_info;
1044         if (access & SNDRV_CTL_ELEM_ACCESS_READ)
1045                 kctl.get = snd_ctl_elem_user_get;
1046         if (access & SNDRV_CTL_ELEM_ACCESS_WRITE)
1047                 kctl.put = snd_ctl_elem_user_put;
1048         if (access & SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE) {
1049                 kctl.tlv.c = snd_ctl_elem_user_tlv;
1050                 access |= SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
1051         }
1052         switch (info->type) {
1053         case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
1054         case SNDRV_CTL_ELEM_TYPE_INTEGER:
1055                 private_size = sizeof(long);
1056                 if (info->count > 128)
1057                         return -EINVAL;
1058                 break;
1059         case SNDRV_CTL_ELEM_TYPE_INTEGER64:
1060                 private_size = sizeof(long long);
1061                 if (info->count > 64)
1062                         return -EINVAL;
1063                 break;
1064         case SNDRV_CTL_ELEM_TYPE_BYTES:
1065                 private_size = sizeof(unsigned char);
1066                 if (info->count > 512)
1067                         return -EINVAL;
1068                 break;
1069         case SNDRV_CTL_ELEM_TYPE_IEC958:
1070                 private_size = sizeof(struct snd_aes_iec958);
1071                 if (info->count != 1)
1072                         return -EINVAL;
1073                 break;
1074         default:
1075                 return -EINVAL;
1076         }
1077         private_size *= info->count;
1078         ue = kzalloc(sizeof(struct user_element) + private_size, GFP_KERNEL);
1079         if (ue == NULL)
1080                 return -ENOMEM;
1081         ue->info = *info;
1082         ue->info.access = 0;
1083         ue->elem_data = (char *)ue + sizeof(*ue);
1084         ue->elem_data_size = private_size;
1085         kctl.private_free = snd_ctl_elem_user_free;
1086         _kctl = snd_ctl_new(&kctl, access);
1087         if (_kctl == NULL) {
1088                 kfree(ue);
1089                 return -ENOMEM;
1090         }
1091         _kctl->private_data = ue;
1092         for (idx = 0; idx < _kctl->count; idx++)
1093                 _kctl->vd[idx].owner = file;
1094         err = snd_ctl_add(card, _kctl);
1095         if (err < 0)
1096                 return err;
1097
1098         down_write(&card->controls_rwsem);
1099         card->user_ctl_count++;
1100         up_write(&card->controls_rwsem);
1101
1102         return 0;
1103 }
1104
1105 static int snd_ctl_elem_add_user(struct snd_ctl_file *file,
1106                                  struct snd_ctl_elem_info __user *_info, int replace)
1107 {
1108         struct snd_ctl_elem_info info;
1109         if (copy_from_user(&info, _info, sizeof(info)))
1110                 return -EFAULT;
1111         return snd_ctl_elem_add(file, &info, replace);
1112 }
1113
1114 static int snd_ctl_elem_remove(struct snd_ctl_file *file,
1115                                struct snd_ctl_elem_id __user *_id)
1116 {
1117         struct snd_ctl_elem_id id;
1118
1119         if (copy_from_user(&id, _id, sizeof(id)))
1120                 return -EFAULT;
1121         return snd_ctl_remove_user_ctl(file, &id);
1122 }
1123
1124 static int snd_ctl_subscribe_events(struct snd_ctl_file *file, int __user *ptr)
1125 {
1126         int subscribe;
1127         if (get_user(subscribe, ptr))
1128                 return -EFAULT;
1129         if (subscribe < 0) {
1130                 subscribe = file->subscribed;
1131                 if (put_user(subscribe, ptr))
1132                         return -EFAULT;
1133                 return 0;
1134         }
1135         if (subscribe) {
1136                 file->subscribed = 1;
1137                 return 0;
1138         } else if (file->subscribed) {
1139                 snd_ctl_empty_read_queue(file);
1140                 file->subscribed = 0;
1141         }
1142         return 0;
1143 }
1144
1145 static int snd_ctl_tlv_ioctl(struct snd_ctl_file *file,
1146                              struct snd_ctl_tlv __user *_tlv,
1147                              int op_flag)
1148 {
1149         struct snd_card *card = file->card;
1150         struct snd_ctl_tlv tlv;
1151         struct snd_kcontrol *kctl;
1152         struct snd_kcontrol_volatile *vd;
1153         unsigned int len;
1154         int err = 0;
1155
1156         if (copy_from_user(&tlv, _tlv, sizeof(tlv)))
1157                 return -EFAULT;
1158         if (tlv.length < sizeof(unsigned int) * 2)
1159                 return -EINVAL;
1160         down_read(&card->controls_rwsem);
1161         kctl = snd_ctl_find_numid(card, tlv.numid);
1162         if (kctl == NULL) {
1163                 err = -ENOENT;
1164                 goto __kctl_end;
1165         }
1166         if (kctl->tlv.p == NULL) {
1167                 err = -ENXIO;
1168                 goto __kctl_end;
1169         }
1170         vd = &kctl->vd[tlv.numid - kctl->id.numid];
1171         if ((op_flag == 0 && (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_READ) == 0) ||
1172             (op_flag > 0 && (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_WRITE) == 0) ||
1173             (op_flag < 0 && (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND) == 0)) {
1174                 err = -ENXIO;
1175                 goto __kctl_end;
1176         }
1177         if (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK) {
1178                 if (vd->owner != NULL && vd->owner != file) {
1179                         err = -EPERM;
1180                         goto __kctl_end;
1181                 }
1182                 err = kctl->tlv.c(kctl, op_flag, tlv.length, _tlv->tlv);
1183                 if (err > 0) {
1184                         up_read(&card->controls_rwsem);
1185                         snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_TLV, &kctl->id);
1186                         return 0;
1187                 }
1188         } else {
1189                 if (op_flag) {
1190                         err = -ENXIO;
1191                         goto __kctl_end;
1192                 }
1193                 len = kctl->tlv.p[1] + 2 * sizeof(unsigned int);
1194                 if (tlv.length < len) {
1195                         err = -ENOMEM;
1196                         goto __kctl_end;
1197                 }
1198                 if (copy_to_user(_tlv->tlv, kctl->tlv.p, len))
1199                         err = -EFAULT;
1200         }
1201       __kctl_end:
1202         up_read(&card->controls_rwsem);
1203         return err;
1204 }
1205
1206 static long snd_ctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1207 {
1208         struct snd_ctl_file *ctl;
1209         struct snd_card *card;
1210         struct snd_kctl_ioctl *p;
1211         void __user *argp = (void __user *)arg;
1212         int __user *ip = argp;
1213         int err;
1214
1215         ctl = file->private_data;
1216         card = ctl->card;
1217         if (snd_BUG_ON(!card))
1218                 return -ENXIO;
1219         switch (cmd) {
1220         case SNDRV_CTL_IOCTL_PVERSION:
1221                 return put_user(SNDRV_CTL_VERSION, ip) ? -EFAULT : 0;
1222         case SNDRV_CTL_IOCTL_CARD_INFO:
1223                 return snd_ctl_card_info(card, ctl, cmd, argp);
1224         case SNDRV_CTL_IOCTL_ELEM_LIST:
1225                 return snd_ctl_elem_list(card, argp);
1226         case SNDRV_CTL_IOCTL_ELEM_INFO:
1227                 return snd_ctl_elem_info_user(ctl, argp);
1228         case SNDRV_CTL_IOCTL_ELEM_READ:
1229                 return snd_ctl_elem_read_user(card, argp);
1230         case SNDRV_CTL_IOCTL_ELEM_WRITE:
1231                 return snd_ctl_elem_write_user(ctl, argp);
1232         case SNDRV_CTL_IOCTL_ELEM_LOCK:
1233                 return snd_ctl_elem_lock(ctl, argp);
1234         case SNDRV_CTL_IOCTL_ELEM_UNLOCK:
1235                 return snd_ctl_elem_unlock(ctl, argp);
1236         case SNDRV_CTL_IOCTL_ELEM_ADD:
1237                 return snd_ctl_elem_add_user(ctl, argp, 0);
1238         case SNDRV_CTL_IOCTL_ELEM_REPLACE:
1239                 return snd_ctl_elem_add_user(ctl, argp, 1);
1240         case SNDRV_CTL_IOCTL_ELEM_REMOVE:
1241                 return snd_ctl_elem_remove(ctl, argp);
1242         case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS:
1243                 return snd_ctl_subscribe_events(ctl, ip);
1244         case SNDRV_CTL_IOCTL_TLV_READ:
1245                 return snd_ctl_tlv_ioctl(ctl, argp, 0);
1246         case SNDRV_CTL_IOCTL_TLV_WRITE:
1247                 return snd_ctl_tlv_ioctl(ctl, argp, 1);
1248         case SNDRV_CTL_IOCTL_TLV_COMMAND:
1249                 return snd_ctl_tlv_ioctl(ctl, argp, -1);
1250         case SNDRV_CTL_IOCTL_POWER:
1251                 return -ENOPROTOOPT;
1252         case SNDRV_CTL_IOCTL_POWER_STATE:
1253 #ifdef CONFIG_PM
1254                 return put_user(card->power_state, ip) ? -EFAULT : 0;
1255 #else
1256                 return put_user(SNDRV_CTL_POWER_D0, ip) ? -EFAULT : 0;
1257 #endif
1258         }
1259         down_read(&snd_ioctl_rwsem);
1260         list_for_each_entry(p, &snd_control_ioctls, list) {
1261                 err = p->fioctl(card, ctl, cmd, arg);
1262                 if (err != -ENOIOCTLCMD) {
1263                         up_read(&snd_ioctl_rwsem);
1264                         return err;
1265                 }
1266         }
1267         up_read(&snd_ioctl_rwsem);
1268         snd_printdd("unknown ioctl = 0x%x\n", cmd);
1269         return -ENOTTY;
1270 }
1271
1272 static ssize_t snd_ctl_read(struct file *file, char __user *buffer,
1273                             size_t count, loff_t * offset)
1274 {
1275         struct snd_ctl_file *ctl;
1276         int err = 0;
1277         ssize_t result = 0;
1278
1279         ctl = file->private_data;
1280         if (snd_BUG_ON(!ctl || !ctl->card))
1281                 return -ENXIO;
1282         if (!ctl->subscribed)
1283                 return -EBADFD;
1284         if (count < sizeof(struct snd_ctl_event))
1285                 return -EINVAL;
1286         spin_lock_irq(&ctl->read_lock);
1287         while (count >= sizeof(struct snd_ctl_event)) {
1288                 struct snd_ctl_event ev;
1289                 struct snd_kctl_event *kev;
1290                 while (list_empty(&ctl->events)) {
1291                         wait_queue_t wait;
1292                         if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) {
1293                                 err = -EAGAIN;
1294                                 goto __end_lock;
1295                         }
1296                         init_waitqueue_entry(&wait, current);
1297                         add_wait_queue(&ctl->change_sleep, &wait);
1298                         set_current_state(TASK_INTERRUPTIBLE);
1299                         spin_unlock_irq(&ctl->read_lock);
1300                         schedule();
1301                         remove_wait_queue(&ctl->change_sleep, &wait);
1302                         if (signal_pending(current))
1303                                 return -ERESTARTSYS;
1304                         spin_lock_irq(&ctl->read_lock);
1305                 }
1306                 kev = snd_kctl_event(ctl->events.next);
1307                 ev.type = SNDRV_CTL_EVENT_ELEM;
1308                 ev.data.elem.mask = kev->mask;
1309                 ev.data.elem.id = kev->id;
1310                 list_del(&kev->list);
1311                 spin_unlock_irq(&ctl->read_lock);
1312                 kfree(kev);
1313                 if (copy_to_user(buffer, &ev, sizeof(struct snd_ctl_event))) {
1314                         err = -EFAULT;
1315                         goto __end;
1316                 }
1317                 spin_lock_irq(&ctl->read_lock);
1318                 buffer += sizeof(struct snd_ctl_event);
1319                 count -= sizeof(struct snd_ctl_event);
1320                 result += sizeof(struct snd_ctl_event);
1321         }
1322       __end_lock:
1323         spin_unlock_irq(&ctl->read_lock);
1324       __end:
1325         return result > 0 ? result : err;
1326 }
1327
1328 static unsigned int snd_ctl_poll(struct file *file, poll_table * wait)
1329 {
1330         unsigned int mask;
1331         struct snd_ctl_file *ctl;
1332
1333         ctl = file->private_data;
1334         if (!ctl->subscribed)
1335                 return 0;
1336         poll_wait(file, &ctl->change_sleep, wait);
1337
1338         mask = 0;
1339         if (!list_empty(&ctl->events))
1340                 mask |= POLLIN | POLLRDNORM;
1341
1342         return mask;
1343 }
1344
1345 /*
1346  * register the device-specific control-ioctls.
1347  * called from each device manager like pcm.c, hwdep.c, etc.
1348  */
1349 static int _snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn, struct list_head *lists)
1350 {
1351         struct snd_kctl_ioctl *pn;
1352
1353         pn = kzalloc(sizeof(struct snd_kctl_ioctl), GFP_KERNEL);
1354         if (pn == NULL)
1355                 return -ENOMEM;
1356         pn->fioctl = fcn;
1357         down_write(&snd_ioctl_rwsem);
1358         list_add_tail(&pn->list, lists);
1359         up_write(&snd_ioctl_rwsem);
1360         return 0;
1361 }
1362
1363 int snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn)
1364 {
1365         return _snd_ctl_register_ioctl(fcn, &snd_control_ioctls);
1366 }
1367
1368 EXPORT_SYMBOL(snd_ctl_register_ioctl);
1369
1370 #ifdef CONFIG_COMPAT
1371 int snd_ctl_register_ioctl_compat(snd_kctl_ioctl_func_t fcn)
1372 {
1373         return _snd_ctl_register_ioctl(fcn, &snd_control_compat_ioctls);
1374 }
1375
1376 EXPORT_SYMBOL(snd_ctl_register_ioctl_compat);
1377 #endif
1378
1379 /*
1380  * de-register the device-specific control-ioctls.
1381  */
1382 static int _snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn,
1383                                      struct list_head *lists)
1384 {
1385         struct snd_kctl_ioctl *p;
1386
1387         if (snd_BUG_ON(!fcn))
1388                 return -EINVAL;
1389         down_write(&snd_ioctl_rwsem);
1390         list_for_each_entry(p, lists, list) {
1391                 if (p->fioctl == fcn) {
1392                         list_del(&p->list);
1393                         up_write(&snd_ioctl_rwsem);
1394                         kfree(p);
1395                         return 0;
1396                 }
1397         }
1398         up_write(&snd_ioctl_rwsem);
1399         snd_BUG();
1400         return -EINVAL;
1401 }
1402
1403 int snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn)
1404 {
1405         return _snd_ctl_unregister_ioctl(fcn, &snd_control_ioctls);
1406 }
1407
1408 EXPORT_SYMBOL(snd_ctl_unregister_ioctl);
1409
1410 #ifdef CONFIG_COMPAT
1411 int snd_ctl_unregister_ioctl_compat(snd_kctl_ioctl_func_t fcn)
1412 {
1413         return _snd_ctl_unregister_ioctl(fcn, &snd_control_compat_ioctls);
1414 }
1415
1416 EXPORT_SYMBOL(snd_ctl_unregister_ioctl_compat);
1417 #endif
1418
1419 static int snd_ctl_fasync(int fd, struct file * file, int on)
1420 {
1421         struct snd_ctl_file *ctl;
1422
1423         ctl = file->private_data;
1424         return fasync_helper(fd, file, on, &ctl->fasync);
1425 }
1426
1427 /*
1428  * ioctl32 compat
1429  */
1430 #ifdef CONFIG_COMPAT
1431 #include "control_compat.c"
1432 #else
1433 #define snd_ctl_ioctl_compat    NULL
1434 #endif
1435
1436 /*
1437  *  INIT PART
1438  */
1439
1440 static const struct file_operations snd_ctl_f_ops =
1441 {
1442         .owner =        THIS_MODULE,
1443         .read =         snd_ctl_read,
1444         .open =         snd_ctl_open,
1445         .release =      snd_ctl_release,
1446         .llseek =       no_llseek,
1447         .poll =         snd_ctl_poll,
1448         .unlocked_ioctl =       snd_ctl_ioctl,
1449         .compat_ioctl = snd_ctl_ioctl_compat,
1450         .fasync =       snd_ctl_fasync,
1451 };
1452
1453 /*
1454  * registration of the control device
1455  */
1456 static int snd_ctl_dev_register(struct snd_device *device)
1457 {
1458         struct snd_card *card = device->device_data;
1459         int err, cardnum;
1460         char name[16];
1461
1462         if (snd_BUG_ON(!card))
1463                 return -ENXIO;
1464         cardnum = card->number;
1465         if (snd_BUG_ON(cardnum < 0 || cardnum >= SNDRV_CARDS))
1466                 return -ENXIO;
1467         sprintf(name, "controlC%i", cardnum);
1468         if ((err = snd_register_device(SNDRV_DEVICE_TYPE_CONTROL, card, -1,
1469                                        &snd_ctl_f_ops, card, name)) < 0)
1470                 return err;
1471         return 0;
1472 }
1473
1474 /*
1475  * disconnection of the control device
1476  */
1477 static int snd_ctl_dev_disconnect(struct snd_device *device)
1478 {
1479         struct snd_card *card = device->device_data;
1480         struct snd_ctl_file *ctl;
1481         int err, cardnum;
1482
1483         if (snd_BUG_ON(!card))
1484                 return -ENXIO;
1485         cardnum = card->number;
1486         if (snd_BUG_ON(cardnum < 0 || cardnum >= SNDRV_CARDS))
1487                 return -ENXIO;
1488
1489         read_lock(&card->ctl_files_rwlock);
1490         list_for_each_entry(ctl, &card->ctl_files, list) {
1491                 wake_up(&ctl->change_sleep);
1492                 kill_fasync(&ctl->fasync, SIGIO, POLL_ERR);
1493         }
1494         read_unlock(&card->ctl_files_rwlock);
1495
1496         if ((err = snd_unregister_device(SNDRV_DEVICE_TYPE_CONTROL,
1497                                          card, -1)) < 0)
1498                 return err;
1499         return 0;
1500 }
1501
1502 /*
1503  * free all controls
1504  */
1505 static int snd_ctl_dev_free(struct snd_device *device)
1506 {
1507         struct snd_card *card = device->device_data;
1508         struct snd_kcontrol *control;
1509
1510         down_write(&card->controls_rwsem);
1511         while (!list_empty(&card->controls)) {
1512                 control = snd_kcontrol(card->controls.next);
1513                 snd_ctl_remove(card, control);
1514         }
1515         up_write(&card->controls_rwsem);
1516         return 0;
1517 }
1518
1519 /*
1520  * create control core:
1521  * called from init.c
1522  */
1523 int snd_ctl_create(struct snd_card *card)
1524 {
1525         static struct snd_device_ops ops = {
1526                 .dev_free = snd_ctl_dev_free,
1527                 .dev_register = snd_ctl_dev_register,
1528                 .dev_disconnect = snd_ctl_dev_disconnect,
1529         };
1530
1531         if (snd_BUG_ON(!card))
1532                 return -ENXIO;
1533         return snd_device_new(card, SNDRV_DEV_CONTROL, card, &ops);
1534 }
1535
1536 /*
1537  * Frequently used control callbacks/helpers
1538  */
1539 int snd_ctl_boolean_mono_info(struct snd_kcontrol *kcontrol,
1540                               struct snd_ctl_elem_info *uinfo)
1541 {
1542         uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
1543         uinfo->count = 1;
1544         uinfo->value.integer.min = 0;
1545         uinfo->value.integer.max = 1;
1546         return 0;
1547 }
1548
1549 EXPORT_SYMBOL(snd_ctl_boolean_mono_info);
1550
1551 int snd_ctl_boolean_stereo_info(struct snd_kcontrol *kcontrol,
1552                                 struct snd_ctl_elem_info *uinfo)
1553 {
1554         uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
1555         uinfo->count = 2;
1556         uinfo->value.integer.min = 0;
1557         uinfo->value.integer.max = 1;
1558         return 0;
1559 }
1560
1561 EXPORT_SYMBOL(snd_ctl_boolean_stereo_info);
1562
1563 /**
1564  * snd_ctl_enum_info - fills the info structure for an enumerated control
1565  * @info: the structure to be filled
1566  * @channels: the number of the control's channels; often one
1567  * @items: the number of control values; also the size of @names
1568  * @names: an array containing the names of all control values
1569  *
1570  * Sets all required fields in @info to their appropriate values.
1571  * If the control's accessibility is not the default (readable and writable),
1572  * the caller has to fill @info->access.
1573  */
1574 int snd_ctl_enum_info(struct snd_ctl_elem_info *info, unsigned int channels,
1575                       unsigned int items, const char *const names[])
1576 {
1577         info->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED;
1578         info->count = channels;
1579         info->value.enumerated.items = items;
1580         if (info->value.enumerated.item >= items)
1581                 info->value.enumerated.item = items - 1;
1582         strlcpy(info->value.enumerated.name,
1583                 names[info->value.enumerated.item],
1584                 sizeof(info->value.enumerated.name));
1585         return 0;
1586 }
1587 EXPORT_SYMBOL(snd_ctl_enum_info);