sound/core/control.c

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