microblaze: uaccess: fix put_user and get_user macros
[linux-2.6.git] / 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
35 struct snd_kctl_ioctl {
36         struct list_head list;          /* list of all ioctls */
37         snd_kctl_ioctl_func_t fioctl;
38 };
39
40 static DECLARE_RWSEM(snd_ioctl_rwsem);
41 static LIST_HEAD(snd_control_ioctls);
42 #ifdef CONFIG_COMPAT
43 static LIST_HEAD(snd_control_compat_ioctls);
44 #endif
45
46 static int snd_ctl_open(struct inode *inode, struct file *file)
47 {
48         unsigned long flags;
49         struct snd_card *card;
50         struct snd_ctl_file *ctl;
51         int err;
52
53         card = snd_lookup_minor_data(iminor(inode), SNDRV_DEVICE_TYPE_CONTROL);
54         if (!card) {
55                 err = -ENODEV;
56                 goto __error1;
57         }
58         err = snd_card_file_add(card, file);
59         if (err < 0) {
60                 err = -ENODEV;
61                 goto __error1;
62         }
63         if (!try_module_get(card->module)) {
64                 err = -EFAULT;
65                 goto __error2;
66         }
67         ctl = kzalloc(sizeof(*ctl), GFP_KERNEL);
68         if (ctl == NULL) {
69                 err = -ENOMEM;
70                 goto __error;
71         }
72         INIT_LIST_HEAD(&ctl->events);
73         init_waitqueue_head(&ctl->change_sleep);
74         spin_lock_init(&ctl->read_lock);
75         ctl->card = card;
76         ctl->prefer_pcm_subdevice = -1;
77         ctl->prefer_rawmidi_subdevice = -1;
78         ctl->pid = get_pid(task_pid(current));
79         file->private_data = ctl;
80         write_lock_irqsave(&card->ctl_files_rwlock, flags);
81         list_add_tail(&ctl->list, &card->ctl_files);
82         write_unlock_irqrestore(&card->ctl_files_rwlock, flags);
83         return 0;
84
85       __error:
86         module_put(card->module);
87       __error2:
88         snd_card_file_remove(card, file);
89       __error1:
90         return err;
91 }
92
93 static void snd_ctl_empty_read_queue(struct snd_ctl_file * ctl)
94 {
95         unsigned long flags;
96         struct snd_kctl_event *cread;
97         
98         spin_lock_irqsave(&ctl->read_lock, flags);
99         while (!list_empty(&ctl->events)) {
100                 cread = snd_kctl_event(ctl->events.next);
101                 list_del(&cread->list);
102                 kfree(cread);
103         }
104         spin_unlock_irqrestore(&ctl->read_lock, flags);
105 }
106
107 static int snd_ctl_release(struct inode *inode, struct file *file)
108 {
109         unsigned long flags;
110         struct snd_card *card;
111         struct snd_ctl_file *ctl;
112         struct snd_kcontrol *control;
113         unsigned int idx;
114
115         ctl = file->private_data;
116         file->private_data = NULL;
117         card = ctl->card;
118         write_lock_irqsave(&card->ctl_files_rwlock, flags);
119         list_del(&ctl->list);
120         write_unlock_irqrestore(&card->ctl_files_rwlock, flags);
121         down_write(&card->controls_rwsem);
122         list_for_each_entry(control, &card->controls, list)
123                 for (idx = 0; idx < control->count; idx++)
124                         if (control->vd[idx].owner == ctl)
125                                 control->vd[idx].owner = NULL;
126         up_write(&card->controls_rwsem);
127         snd_ctl_empty_read_queue(ctl);
128         put_pid(ctl->pid);
129         kfree(ctl);
130         module_put(card->module);
131         snd_card_file_remove(card, file);
132         return 0;
133 }
134
135 void snd_ctl_notify(struct snd_card *card, unsigned int mask,
136                     struct snd_ctl_elem_id *id)
137 {
138         unsigned long flags;
139         struct snd_ctl_file *ctl;
140         struct snd_kctl_event *ev;
141         
142         if (snd_BUG_ON(!card || !id))
143                 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 static struct snd_kcontrol *snd_ctl_new(struct snd_kcontrol *control,
187                                         unsigned int access)
188 {
189         struct snd_kcontrol *kctl;
190         unsigned int idx;
191         
192         if (snd_BUG_ON(!control || !control->count))
193                 return NULL;
194         kctl = kzalloc(sizeof(*kctl) + sizeof(struct snd_kcontrol_volatile) * control->count, GFP_KERNEL);
195         if (kctl == NULL) {
196                 snd_printk(KERN_ERR "Cannot allocate control instance\n");
197                 return NULL;
198         }
199         *kctl = *control;
200         for (idx = 0; idx < kctl->count; idx++)
201                 kctl->vd[idx].access = access;
202         return kctl;
203 }
204
205 /**
206  * snd_ctl_new1 - create a control instance from the template
207  * @ncontrol: the initialization record
208  * @private_data: the private data to set
209  *
210  * Allocates a new struct snd_kcontrol instance and initialize from the given 
211  * template.  When the access field of ncontrol is 0, it's assumed as
212  * READWRITE access. When the count field is 0, it's assumes as one.
213  *
214  * Returns the pointer of the newly generated instance, or NULL on failure.
215  */
216 struct snd_kcontrol *snd_ctl_new1(const struct snd_kcontrol_new *ncontrol,
217                                   void *private_data)
218 {
219         struct snd_kcontrol kctl;
220         unsigned int access;
221         
222         if (snd_BUG_ON(!ncontrol || !ncontrol->info))
223                 return NULL;
224         memset(&kctl, 0, sizeof(kctl));
225         kctl.id.iface = ncontrol->iface;
226         kctl.id.device = ncontrol->device;
227         kctl.id.subdevice = ncontrol->subdevice;
228         if (ncontrol->name) {
229                 strlcpy(kctl.id.name, ncontrol->name, sizeof(kctl.id.name));
230                 if (strcmp(ncontrol->name, kctl.id.name) != 0)
231                         snd_printk(KERN_WARNING
232                                    "Control name '%s' truncated to '%s'\n",
233                                    ncontrol->name, kctl.id.name);
234         }
235         kctl.id.index = ncontrol->index;
236         kctl.count = ncontrol->count ? ncontrol->count : 1;
237         access = ncontrol->access == 0 ? SNDRV_CTL_ELEM_ACCESS_READWRITE :
238                  (ncontrol->access & (SNDRV_CTL_ELEM_ACCESS_READWRITE|
239                                       SNDRV_CTL_ELEM_ACCESS_INACTIVE|
240                                       SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE|
241                                       SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND|
242                                       SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK));
243         kctl.info = ncontrol->info;
244         kctl.get = ncontrol->get;
245         kctl.put = ncontrol->put;
246         kctl.tlv.p = ncontrol->tlv.p;
247         kctl.private_value = ncontrol->private_value;
248         kctl.private_data = private_data;
249         return snd_ctl_new(&kctl, access);
250 }
251
252 EXPORT_SYMBOL(snd_ctl_new1);
253
254 /**
255  * snd_ctl_free_one - release the control instance
256  * @kcontrol: the control instance
257  *
258  * Releases the control instance created via snd_ctl_new()
259  * or snd_ctl_new1().
260  * Don't call this after the control was added to the card.
261  */
262 void snd_ctl_free_one(struct snd_kcontrol *kcontrol)
263 {
264         if (kcontrol) {
265                 if (kcontrol->private_free)
266                         kcontrol->private_free(kcontrol);
267                 kfree(kcontrol);
268         }
269 }
270
271 EXPORT_SYMBOL(snd_ctl_free_one);
272
273 static unsigned int snd_ctl_hole_check(struct snd_card *card,
274                                        unsigned int count)
275 {
276         struct snd_kcontrol *kctl;
277
278         list_for_each_entry(kctl, &card->controls, list) {
279                 if ((kctl->id.numid <= card->last_numid &&
280                      kctl->id.numid + kctl->count > card->last_numid) ||
281                     (kctl->id.numid <= card->last_numid + count - 1 &&
282                      kctl->id.numid + kctl->count > card->last_numid + count - 1))
283                         return card->last_numid = kctl->id.numid + kctl->count - 1;
284         }
285         return card->last_numid;
286 }
287
288 static int snd_ctl_find_hole(struct snd_card *card, unsigned int count)
289 {
290         unsigned int last_numid, iter = 100000;
291
292         last_numid = card->last_numid;
293         while (last_numid != snd_ctl_hole_check(card, count)) {
294                 if (--iter == 0) {
295                         /* this situation is very unlikely */
296                         snd_printk(KERN_ERR "unable to allocate new control numid\n");
297                         return -ENOMEM;
298                 }
299                 last_numid = card->last_numid;
300         }
301         return 0;
302 }
303
304 /**
305  * snd_ctl_add - add the control instance to the card
306  * @card: the card instance
307  * @kcontrol: the control instance to add
308  *
309  * Adds the control instance created via snd_ctl_new() or
310  * snd_ctl_new1() to the given card. Assigns also an unique
311  * numid used for fast search.
312  *
313  * Returns zero if successful, or a negative error code on failure.
314  *
315  * It frees automatically the control which cannot be added.
316  */
317 int snd_ctl_add(struct snd_card *card, struct snd_kcontrol *kcontrol)
318 {
319         struct snd_ctl_elem_id id;
320         unsigned int idx;
321         int err = -EINVAL;
322
323         if (! kcontrol)
324                 return err;
325         if (snd_BUG_ON(!card || !kcontrol->info))
326                 goto error;
327         id = kcontrol->id;
328         down_write(&card->controls_rwsem);
329         if (snd_ctl_find_id(card, &id)) {
330                 up_write(&card->controls_rwsem);
331                 snd_printd(KERN_ERR "control %i:%i:%i:%s:%i is already present\n",
332                                         id.iface,
333                                         id.device,
334                                         id.subdevice,
335                                         id.name,
336                                         id.index);
337                 err = -EBUSY;
338                 goto error;
339         }
340         if (snd_ctl_find_hole(card, kcontrol->count) < 0) {
341                 up_write(&card->controls_rwsem);
342                 err = -ENOMEM;
343                 goto error;
344         }
345         list_add_tail(&kcontrol->list, &card->controls);
346         card->controls_count += kcontrol->count;
347         kcontrol->id.numid = card->last_numid + 1;
348         card->last_numid += kcontrol->count;
349         up_write(&card->controls_rwsem);
350         for (idx = 0; idx < kcontrol->count; idx++, id.index++, id.numid++)
351                 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_ADD, &id);
352         return 0;
353
354  error:
355         snd_ctl_free_one(kcontrol);
356         return err;
357 }
358
359 EXPORT_SYMBOL(snd_ctl_add);
360
361 /**
362  * snd_ctl_remove - remove the control from the card and release it
363  * @card: the card instance
364  * @kcontrol: the control instance to remove
365  *
366  * Removes the control from the card and then releases the instance.
367  * You don't need to call snd_ctl_free_one(). You must be in
368  * the write lock - down_write(&card->controls_rwsem).
369  * 
370  * Returns 0 if successful, or a negative error code on failure.
371  */
372 int snd_ctl_remove(struct snd_card *card, struct snd_kcontrol *kcontrol)
373 {
374         struct snd_ctl_elem_id id;
375         unsigned int idx;
376
377         if (snd_BUG_ON(!card || !kcontrol))
378                 return -EINVAL;
379         list_del(&kcontrol->list);
380         card->controls_count -= kcontrol->count;
381         id = kcontrol->id;
382         for (idx = 0; idx < kcontrol->count; idx++, id.index++, id.numid++)
383                 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_REMOVE, &id);
384         snd_ctl_free_one(kcontrol);
385         return 0;
386 }
387
388 EXPORT_SYMBOL(snd_ctl_remove);
389
390 /**
391  * snd_ctl_remove_id - remove the control of the given id and release it
392  * @card: the card instance
393  * @id: the control id to remove
394  *
395  * Finds the control instance with the given id, removes it from the
396  * card list and releases it.
397  * 
398  * Returns 0 if successful, or a negative error code on failure.
399  */
400 int snd_ctl_remove_id(struct snd_card *card, struct snd_ctl_elem_id *id)
401 {
402         struct snd_kcontrol *kctl;
403         int ret;
404
405         down_write(&card->controls_rwsem);
406         kctl = snd_ctl_find_id(card, id);
407         if (kctl == NULL) {
408                 up_write(&card->controls_rwsem);
409                 return -ENOENT;
410         }
411         ret = snd_ctl_remove(card, kctl);
412         up_write(&card->controls_rwsem);
413         return ret;
414 }
415
416 EXPORT_SYMBOL(snd_ctl_remove_id);
417
418 /**
419  * snd_ctl_remove_user_ctl - remove and release the unlocked user control
420  * @file: active control handle
421  * @id: the control id to remove
422  *
423  * Finds the control instance with the given id, removes it from the
424  * card list and releases it.
425  * 
426  * Returns 0 if successful, or a negative error code on failure.
427  */
428 static int snd_ctl_remove_user_ctl(struct snd_ctl_file * file,
429                                    struct snd_ctl_elem_id *id)
430 {
431         struct snd_card *card = file->card;
432         struct snd_kcontrol *kctl;
433         int idx, ret;
434
435         down_write(&card->controls_rwsem);
436         kctl = snd_ctl_find_id(card, id);
437         if (kctl == NULL) {
438                 ret = -ENOENT;
439                 goto error;
440         }
441         if (!(kctl->vd[0].access & SNDRV_CTL_ELEM_ACCESS_USER)) {
442                 ret = -EINVAL;
443                 goto error;
444         }
445         for (idx = 0; idx < kctl->count; idx++)
446                 if (kctl->vd[idx].owner != NULL && kctl->vd[idx].owner != file) {
447                         ret = -EBUSY;
448                         goto error;
449                 }
450         ret = snd_ctl_remove(card, kctl);
451         if (ret < 0)
452                 goto error;
453         card->user_ctl_count--;
454 error:
455         up_write(&card->controls_rwsem);
456         return ret;
457 }
458
459 /**
460  * snd_ctl_rename_id - replace the id of a control on the card
461  * @card: the card instance
462  * @src_id: the old id
463  * @dst_id: the new id
464  *
465  * Finds the control with the old id from the card, and replaces the
466  * id with the new one.
467  *
468  * Returns zero if successful, or a negative error code on failure.
469  */
470 int snd_ctl_rename_id(struct snd_card *card, struct snd_ctl_elem_id *src_id,
471                       struct snd_ctl_elem_id *dst_id)
472 {
473         struct snd_kcontrol *kctl;
474
475         down_write(&card->controls_rwsem);
476         kctl = snd_ctl_find_id(card, src_id);
477         if (kctl == NULL) {
478                 up_write(&card->controls_rwsem);
479                 return -ENOENT;
480         }
481         kctl->id = *dst_id;
482         kctl->id.numid = card->last_numid + 1;
483         card->last_numid += kctl->count;
484         up_write(&card->controls_rwsem);
485         return 0;
486 }
487
488 EXPORT_SYMBOL(snd_ctl_rename_id);
489
490 /**
491  * snd_ctl_find_numid - find the control instance with the given number-id
492  * @card: the card instance
493  * @numid: the number-id to search
494  *
495  * Finds the control instance with the given number-id from the card.
496  *
497  * Returns the pointer of the instance if found, or NULL if not.
498  *
499  * The caller must down card->controls_rwsem before calling this function
500  * (if the race condition can happen).
501  */
502 struct snd_kcontrol *snd_ctl_find_numid(struct snd_card *card, unsigned int numid)
503 {
504         struct snd_kcontrol *kctl;
505
506         if (snd_BUG_ON(!card || !numid))
507                 return NULL;
508         list_for_each_entry(kctl, &card->controls, list) {
509                 if (kctl->id.numid <= numid && kctl->id.numid + kctl->count > numid)
510                         return kctl;
511         }
512         return NULL;
513 }
514
515 EXPORT_SYMBOL(snd_ctl_find_numid);
516
517 /**
518  * snd_ctl_find_id - find the control instance with the given id
519  * @card: the card instance
520  * @id: the id to search
521  *
522  * Finds the control instance with the given id from the card.
523  *
524  * Returns the pointer of the instance if found, or NULL if not.
525  *
526  * The caller must down card->controls_rwsem before calling this function
527  * (if the race condition can happen).
528  */
529 struct snd_kcontrol *snd_ctl_find_id(struct snd_card *card,
530                                      struct snd_ctl_elem_id *id)
531 {
532         struct snd_kcontrol *kctl;
533
534         if (snd_BUG_ON(!card || !id))
535                 return NULL;
536         if (id->numid != 0)
537                 return snd_ctl_find_numid(card, id->numid);
538         list_for_each_entry(kctl, &card->controls, list) {
539                 if (kctl->id.iface != id->iface)
540                         continue;
541                 if (kctl->id.device != id->device)
542                         continue;
543                 if (kctl->id.subdevice != id->subdevice)
544                         continue;
545                 if (strncmp(kctl->id.name, id->name, sizeof(kctl->id.name)))
546                         continue;
547                 if (kctl->id.index > id->index)
548                         continue;
549                 if (kctl->id.index + kctl->count <= id->index)
550                         continue;
551                 return kctl;
552         }
553         return NULL;
554 }
555
556 EXPORT_SYMBOL(snd_ctl_find_id);
557
558 static int snd_ctl_card_info(struct snd_card *card, struct snd_ctl_file * ctl,
559                              unsigned int cmd, void __user *arg)
560 {
561         struct snd_ctl_card_info *info;
562
563         info = kzalloc(sizeof(*info), GFP_KERNEL);
564         if (! info)
565                 return -ENOMEM;
566         down_read(&snd_ioctl_rwsem);
567         info->card = card->number;
568         strlcpy(info->id, card->id, sizeof(info->id));
569         strlcpy(info->driver, card->driver, sizeof(info->driver));
570         strlcpy(info->name, card->shortname, sizeof(info->name));
571         strlcpy(info->longname, card->longname, sizeof(info->longname));
572         strlcpy(info->mixername, card->mixername, sizeof(info->mixername));
573         strlcpy(info->components, card->components, sizeof(info->components));
574         up_read(&snd_ioctl_rwsem);
575         if (copy_to_user(arg, info, sizeof(struct snd_ctl_card_info))) {
576                 kfree(info);
577                 return -EFAULT;
578         }
579         kfree(info);
580         return 0;
581 }
582
583 static int snd_ctl_elem_list(struct snd_card *card,
584                              struct snd_ctl_elem_list __user *_list)
585 {
586         struct list_head *plist;
587         struct snd_ctl_elem_list list;
588         struct snd_kcontrol *kctl;
589         struct snd_ctl_elem_id *dst, *id;
590         unsigned int offset, space, first, jidx;
591         
592         if (copy_from_user(&list, _list, sizeof(list)))
593                 return -EFAULT;
594         offset = list.offset;
595         space = list.space;
596         first = 0;
597         /* try limit maximum space */
598         if (space > 16384)
599                 return -ENOMEM;
600         if (space > 0) {
601                 /* allocate temporary buffer for atomic operation */
602                 dst = vmalloc(space * sizeof(struct snd_ctl_elem_id));
603                 if (dst == NULL)
604                         return -ENOMEM;
605                 down_read(&card->controls_rwsem);
606                 list.count = card->controls_count;
607                 plist = card->controls.next;
608                 while (plist != &card->controls) {
609                         if (offset == 0)
610                                 break;
611                         kctl = snd_kcontrol(plist);
612                         if (offset < kctl->count)
613                                 break;
614                         offset -= kctl->count;
615                         plist = plist->next;
616                 }
617                 list.used = 0;
618                 id = dst;
619                 while (space > 0 && plist != &card->controls) {
620                         kctl = snd_kcontrol(plist);
621                         for (jidx = offset; space > 0 && jidx < kctl->count; jidx++) {
622                                 snd_ctl_build_ioff(id, kctl, jidx);
623                                 id++;
624                                 space--;
625                                 list.used++;
626                         }
627                         plist = plist->next;
628                         offset = 0;
629                 }
630                 up_read(&card->controls_rwsem);
631                 if (list.used > 0 &&
632                     copy_to_user(list.pids, dst,
633                                  list.used * sizeof(struct snd_ctl_elem_id))) {
634                         vfree(dst);
635                         return -EFAULT;
636                 }
637                 vfree(dst);
638         } else {
639                 down_read(&card->controls_rwsem);
640                 list.count = card->controls_count;
641                 up_read(&card->controls_rwsem);
642         }
643         if (copy_to_user(_list, &list, sizeof(list)))
644                 return -EFAULT;
645         return 0;
646 }
647
648 static int snd_ctl_elem_info(struct snd_ctl_file *ctl,
649                              struct snd_ctl_elem_info *info)
650 {
651         struct snd_card *card = ctl->card;
652         struct snd_kcontrol *kctl;
653         struct snd_kcontrol_volatile *vd;
654         unsigned int index_offset;
655         int result;
656         
657         down_read(&card->controls_rwsem);
658         kctl = snd_ctl_find_id(card, &info->id);
659         if (kctl == NULL) {
660                 up_read(&card->controls_rwsem);
661                 return -ENOENT;
662         }
663 #ifdef CONFIG_SND_DEBUG
664         info->access = 0;
665 #endif
666         result = kctl->info(kctl, info);
667         if (result >= 0) {
668                 snd_BUG_ON(info->access);
669                 index_offset = snd_ctl_get_ioff(kctl, &info->id);
670                 vd = &kctl->vd[index_offset];
671                 snd_ctl_build_ioff(&info->id, kctl, index_offset);
672                 info->access = vd->access;
673                 if (vd->owner) {
674                         info->access |= SNDRV_CTL_ELEM_ACCESS_LOCK;
675                         if (vd->owner == ctl)
676                                 info->access |= SNDRV_CTL_ELEM_ACCESS_OWNER;
677                         info->owner = pid_vnr(vd->owner->pid);
678                 } else {
679                         info->owner = -1;
680                 }
681         }
682         up_read(&card->controls_rwsem);
683         return result;
684 }
685
686 static int snd_ctl_elem_info_user(struct snd_ctl_file *ctl,
687                                   struct snd_ctl_elem_info __user *_info)
688 {
689         struct snd_ctl_elem_info info;
690         int result;
691
692         if (copy_from_user(&info, _info, sizeof(info)))
693                 return -EFAULT;
694         snd_power_lock(ctl->card);
695         result = snd_power_wait(ctl->card, SNDRV_CTL_POWER_D0);
696         if (result >= 0)
697                 result = snd_ctl_elem_info(ctl, &info);
698         snd_power_unlock(ctl->card);
699         if (result >= 0)
700                 if (copy_to_user(_info, &info, sizeof(info)))
701                         return -EFAULT;
702         return result;
703 }
704
705 static int snd_ctl_elem_read(struct snd_card *card,
706                              struct snd_ctl_elem_value *control)
707 {
708         struct snd_kcontrol *kctl;
709         struct snd_kcontrol_volatile *vd;
710         unsigned int index_offset;
711         int result;
712
713         down_read(&card->controls_rwsem);
714         kctl = snd_ctl_find_id(card, &control->id);
715         if (kctl == NULL) {
716                 result = -ENOENT;
717         } else {
718                 index_offset = snd_ctl_get_ioff(kctl, &control->id);
719                 vd = &kctl->vd[index_offset];
720                 if ((vd->access & SNDRV_CTL_ELEM_ACCESS_READ) &&
721                     kctl->get != NULL) {
722                         snd_ctl_build_ioff(&control->id, kctl, index_offset);
723                         result = kctl->get(kctl, control);
724                 } else
725                         result = -EPERM;
726         }
727         up_read(&card->controls_rwsem);
728         return result;
729 }
730
731 static int snd_ctl_elem_read_user(struct snd_card *card,
732                                   struct snd_ctl_elem_value __user *_control)
733 {
734         struct snd_ctl_elem_value *control;
735         int result;
736
737         control = memdup_user(_control, sizeof(*control));
738         if (IS_ERR(control))
739                 return PTR_ERR(control);
740
741         snd_power_lock(card);
742         result = snd_power_wait(card, SNDRV_CTL_POWER_D0);
743         if (result >= 0)
744                 result = snd_ctl_elem_read(card, control);
745         snd_power_unlock(card);
746         if (result >= 0)
747                 if (copy_to_user(_control, control, sizeof(*control)))
748                         result = -EFAULT;
749         kfree(control);
750         return result;
751 }
752
753 static int snd_ctl_elem_write(struct snd_card *card, struct snd_ctl_file *file,
754                               struct snd_ctl_elem_value *control)
755 {
756         struct snd_kcontrol *kctl;
757         struct snd_kcontrol_volatile *vd;
758         unsigned int index_offset;
759         int result;
760
761         down_read(&card->controls_rwsem);
762         kctl = snd_ctl_find_id(card, &control->id);
763         if (kctl == NULL) {
764                 result = -ENOENT;
765         } else {
766                 index_offset = snd_ctl_get_ioff(kctl, &control->id);
767                 vd = &kctl->vd[index_offset];
768                 if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_WRITE) ||
769                     kctl->put == NULL ||
770                     (file && vd->owner && vd->owner != file)) {
771                         result = -EPERM;
772                 } else {
773                         snd_ctl_build_ioff(&control->id, kctl, index_offset);
774                         result = kctl->put(kctl, control);
775                 }
776                 if (result > 0) {
777                         up_read(&card->controls_rwsem);
778                         snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
779                                        &control->id);
780                         return 0;
781                 }
782         }
783         up_read(&card->controls_rwsem);
784         return result;
785 }
786
787 static int snd_ctl_elem_write_user(struct snd_ctl_file *file,
788                                    struct snd_ctl_elem_value __user *_control)
789 {
790         struct snd_ctl_elem_value *control;
791         struct snd_card *card;
792         int result;
793
794         control = memdup_user(_control, sizeof(*control));
795         if (IS_ERR(control))
796                 return PTR_ERR(control);
797
798         card = file->card;
799         snd_power_lock(card);
800         result = snd_power_wait(card, SNDRV_CTL_POWER_D0);
801         if (result >= 0)
802                 result = snd_ctl_elem_write(card, file, control);
803         snd_power_unlock(card);
804         if (result >= 0)
805                 if (copy_to_user(_control, control, sizeof(*control)))
806                         result = -EFAULT;
807         kfree(control);
808         return result;
809 }
810
811 static int snd_ctl_elem_lock(struct snd_ctl_file *file,
812                              struct snd_ctl_elem_id __user *_id)
813 {
814         struct snd_card *card = file->card;
815         struct snd_ctl_elem_id id;
816         struct snd_kcontrol *kctl;
817         struct snd_kcontrol_volatile *vd;
818         int result;
819         
820         if (copy_from_user(&id, _id, sizeof(id)))
821                 return -EFAULT;
822         down_write(&card->controls_rwsem);
823         kctl = snd_ctl_find_id(card, &id);
824         if (kctl == NULL) {
825                 result = -ENOENT;
826         } else {
827                 vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)];
828                 if (vd->owner != NULL)
829                         result = -EBUSY;
830                 else {
831                         vd->owner = file;
832                         result = 0;
833                 }
834         }
835         up_write(&card->controls_rwsem);
836         return result;
837 }
838
839 static int snd_ctl_elem_unlock(struct snd_ctl_file *file,
840                                struct snd_ctl_elem_id __user *_id)
841 {
842         struct snd_card *card = file->card;
843         struct snd_ctl_elem_id id;
844         struct snd_kcontrol *kctl;
845         struct snd_kcontrol_volatile *vd;
846         int result;
847         
848         if (copy_from_user(&id, _id, sizeof(id)))
849                 return -EFAULT;
850         down_write(&card->controls_rwsem);
851         kctl = snd_ctl_find_id(card, &id);
852         if (kctl == NULL) {
853                 result = -ENOENT;
854         } else {
855                 vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)];
856                 if (vd->owner == NULL)
857                         result = -EINVAL;
858                 else if (vd->owner != file)
859                         result = -EPERM;
860                 else {
861                         vd->owner = NULL;
862                         result = 0;
863                 }
864         }
865         up_write(&card->controls_rwsem);
866         return result;
867 }
868
869 struct user_element {
870         struct snd_ctl_elem_info info;
871         void *elem_data;                /* element data */
872         unsigned long elem_data_size;   /* size of element data in bytes */
873         void *tlv_data;                 /* TLV data */
874         unsigned long tlv_data_size;    /* TLV data size */
875         void *priv_data;                /* private data (like strings for enumerated type) */
876         unsigned long priv_data_size;   /* size of private data in bytes */
877 };
878
879 static int snd_ctl_elem_user_info(struct snd_kcontrol *kcontrol,
880                                   struct snd_ctl_elem_info *uinfo)
881 {
882         struct user_element *ue = kcontrol->private_data;
883
884         *uinfo = ue->info;
885         return 0;
886 }
887
888 static int snd_ctl_elem_user_get(struct snd_kcontrol *kcontrol,
889                                  struct snd_ctl_elem_value *ucontrol)
890 {
891         struct user_element *ue = kcontrol->private_data;
892
893         memcpy(&ucontrol->value, ue->elem_data, ue->elem_data_size);
894         return 0;
895 }
896
897 static int snd_ctl_elem_user_put(struct snd_kcontrol *kcontrol,
898                                  struct snd_ctl_elem_value *ucontrol)
899 {
900         int change;
901         struct user_element *ue = kcontrol->private_data;
902         
903         change = memcmp(&ucontrol->value, ue->elem_data, ue->elem_data_size) != 0;
904         if (change)
905                 memcpy(ue->elem_data, &ucontrol->value, ue->elem_data_size);
906         return change;
907 }
908
909 static int snd_ctl_elem_user_tlv(struct snd_kcontrol *kcontrol,
910                                  int op_flag,
911                                  unsigned int size,
912                                  unsigned int __user *tlv)
913 {
914         struct user_element *ue = kcontrol->private_data;
915         int change = 0;
916         void *new_data;
917
918         if (op_flag > 0) {
919                 if (size > 1024 * 128)  /* sane value */
920                         return -EINVAL;
921
922                 new_data = memdup_user(tlv, size);
923                 if (IS_ERR(new_data))
924                         return PTR_ERR(new_data);
925                 change = ue->tlv_data_size != size;
926                 if (!change)
927                         change = memcmp(ue->tlv_data, new_data, size);
928                 kfree(ue->tlv_data);
929                 ue->tlv_data = new_data;
930                 ue->tlv_data_size = size;
931         } else {
932                 if (! ue->tlv_data_size || ! ue->tlv_data)
933                         return -ENXIO;
934                 if (size < ue->tlv_data_size)
935                         return -ENOSPC;
936                 if (copy_to_user(tlv, ue->tlv_data, ue->tlv_data_size))
937                         return -EFAULT;
938         }
939         return change;
940 }
941
942 static void snd_ctl_elem_user_free(struct snd_kcontrol *kcontrol)
943 {
944         struct user_element *ue = kcontrol->private_data;
945         if (ue->tlv_data)
946                 kfree(ue->tlv_data);
947         kfree(ue);
948 }
949
950 static int snd_ctl_elem_add(struct snd_ctl_file *file,
951                             struct snd_ctl_elem_info *info, int replace)
952 {
953         struct snd_card *card = file->card;
954         struct snd_kcontrol kctl, *_kctl;
955         unsigned int access;
956         long private_size;
957         struct user_element *ue;
958         int idx, err;
959         
960         if (card->user_ctl_count >= MAX_USER_CONTROLS)
961                 return -ENOMEM;
962         if (info->count < 1)
963                 return -EINVAL;
964         access = info->access == 0 ? SNDRV_CTL_ELEM_ACCESS_READWRITE :
965                 (info->access & (SNDRV_CTL_ELEM_ACCESS_READWRITE|
966                                  SNDRV_CTL_ELEM_ACCESS_INACTIVE|
967                                  SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE));
968         info->id.numid = 0;
969         memset(&kctl, 0, sizeof(kctl));
970         down_write(&card->controls_rwsem);
971         _kctl = snd_ctl_find_id(card, &info->id);
972         err = 0;
973         if (_kctl) {
974                 if (replace)
975                         err = snd_ctl_remove(card, _kctl);
976                 else
977                         err = -EBUSY;
978         } else {
979                 if (replace)
980                         err = -ENOENT;
981         }
982         up_write(&card->controls_rwsem);
983         if (err < 0)
984                 return err;
985         memcpy(&kctl.id, &info->id, sizeof(info->id));
986         kctl.count = info->owner ? info->owner : 1;
987         access |= SNDRV_CTL_ELEM_ACCESS_USER;
988         kctl.info = snd_ctl_elem_user_info;
989         if (access & SNDRV_CTL_ELEM_ACCESS_READ)
990                 kctl.get = snd_ctl_elem_user_get;
991         if (access & SNDRV_CTL_ELEM_ACCESS_WRITE)
992                 kctl.put = snd_ctl_elem_user_put;
993         if (access & SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE) {
994                 kctl.tlv.c = snd_ctl_elem_user_tlv;
995                 access |= SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
996         }
997         switch (info->type) {
998         case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
999         case SNDRV_CTL_ELEM_TYPE_INTEGER:
1000                 private_size = sizeof(long);
1001                 if (info->count > 128)
1002                         return -EINVAL;
1003                 break;
1004         case SNDRV_CTL_ELEM_TYPE_INTEGER64:
1005                 private_size = sizeof(long long);
1006                 if (info->count > 64)
1007                         return -EINVAL;
1008                 break;
1009         case SNDRV_CTL_ELEM_TYPE_BYTES:
1010                 private_size = sizeof(unsigned char);
1011                 if (info->count > 512)
1012                         return -EINVAL;
1013                 break;
1014         case SNDRV_CTL_ELEM_TYPE_IEC958:
1015                 private_size = sizeof(struct snd_aes_iec958);
1016                 if (info->count != 1)
1017                         return -EINVAL;
1018                 break;
1019         default:
1020                 return -EINVAL;
1021         }
1022         private_size *= info->count;
1023         ue = kzalloc(sizeof(struct user_element) + private_size, GFP_KERNEL);
1024         if (ue == NULL)
1025                 return -ENOMEM;
1026         ue->info = *info;
1027         ue->info.access = 0;
1028         ue->elem_data = (char *)ue + sizeof(*ue);
1029         ue->elem_data_size = private_size;
1030         kctl.private_free = snd_ctl_elem_user_free;
1031         _kctl = snd_ctl_new(&kctl, access);
1032         if (_kctl == NULL) {
1033                 kfree(ue);
1034                 return -ENOMEM;
1035         }
1036         _kctl->private_data = ue;
1037         for (idx = 0; idx < _kctl->count; idx++)
1038                 _kctl->vd[idx].owner = file;
1039         err = snd_ctl_add(card, _kctl);
1040         if (err < 0)
1041                 return err;
1042
1043         down_write(&card->controls_rwsem);
1044         card->user_ctl_count++;
1045         up_write(&card->controls_rwsem);
1046
1047         return 0;
1048 }
1049
1050 static int snd_ctl_elem_add_user(struct snd_ctl_file *file,
1051                                  struct snd_ctl_elem_info __user *_info, int replace)
1052 {
1053         struct snd_ctl_elem_info info;
1054         if (copy_from_user(&info, _info, sizeof(info)))
1055                 return -EFAULT;
1056         return snd_ctl_elem_add(file, &info, replace);
1057 }
1058
1059 static int snd_ctl_elem_remove(struct snd_ctl_file *file,
1060                                struct snd_ctl_elem_id __user *_id)
1061 {
1062         struct snd_ctl_elem_id id;
1063
1064         if (copy_from_user(&id, _id, sizeof(id)))
1065                 return -EFAULT;
1066         return snd_ctl_remove_user_ctl(file, &id);
1067 }
1068
1069 static int snd_ctl_subscribe_events(struct snd_ctl_file *file, int __user *ptr)
1070 {
1071         int subscribe;
1072         if (get_user(subscribe, ptr))
1073                 return -EFAULT;
1074         if (subscribe < 0) {
1075                 subscribe = file->subscribed;
1076                 if (put_user(subscribe, ptr))
1077                         return -EFAULT;
1078                 return 0;
1079         }
1080         if (subscribe) {
1081                 file->subscribed = 1;
1082                 return 0;
1083         } else if (file->subscribed) {
1084                 snd_ctl_empty_read_queue(file);
1085                 file->subscribed = 0;
1086         }
1087         return 0;
1088 }
1089
1090 static int snd_ctl_tlv_ioctl(struct snd_ctl_file *file,
1091                              struct snd_ctl_tlv __user *_tlv,
1092                              int op_flag)
1093 {
1094         struct snd_card *card = file->card;
1095         struct snd_ctl_tlv tlv;
1096         struct snd_kcontrol *kctl;
1097         struct snd_kcontrol_volatile *vd;
1098         unsigned int len;
1099         int err = 0;
1100
1101         if (copy_from_user(&tlv, _tlv, sizeof(tlv)))
1102                 return -EFAULT;
1103         if (tlv.length < sizeof(unsigned int) * 2)
1104                 return -EINVAL;
1105         down_read(&card->controls_rwsem);
1106         kctl = snd_ctl_find_numid(card, tlv.numid);
1107         if (kctl == NULL) {
1108                 err = -ENOENT;
1109                 goto __kctl_end;
1110         }
1111         if (kctl->tlv.p == NULL) {
1112                 err = -ENXIO;
1113                 goto __kctl_end;
1114         }
1115         vd = &kctl->vd[tlv.numid - kctl->id.numid];
1116         if ((op_flag == 0 && (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_READ) == 0) ||
1117             (op_flag > 0 && (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_WRITE) == 0) ||
1118             (op_flag < 0 && (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND) == 0)) {
1119                 err = -ENXIO;
1120                 goto __kctl_end;
1121         }
1122         if (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK) {
1123                 if (vd->owner != NULL && vd->owner != file) {
1124                         err = -EPERM;
1125                         goto __kctl_end;
1126                 }
1127                 err = kctl->tlv.c(kctl, op_flag, tlv.length, _tlv->tlv); 
1128                 if (err > 0) {
1129                         up_read(&card->controls_rwsem);
1130                         snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_TLV, &kctl->id);
1131                         return 0;
1132                 }
1133         } else {
1134                 if (op_flag) {
1135                         err = -ENXIO;
1136                         goto __kctl_end;
1137                 }
1138                 len = kctl->tlv.p[1] + 2 * sizeof(unsigned int);
1139                 if (tlv.length < len) {
1140                         err = -ENOMEM;
1141                         goto __kctl_end;
1142                 }
1143                 if (copy_to_user(_tlv->tlv, kctl->tlv.p, len))
1144                         err = -EFAULT;
1145         }
1146       __kctl_end:
1147         up_read(&card->controls_rwsem);
1148         return err;
1149 }
1150
1151 static long snd_ctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1152 {
1153         struct snd_ctl_file *ctl;
1154         struct snd_card *card;
1155         struct snd_kctl_ioctl *p;
1156         void __user *argp = (void __user *)arg;
1157         int __user *ip = argp;
1158         int err;
1159
1160         ctl = file->private_data;
1161         card = ctl->card;
1162         if (snd_BUG_ON(!card))
1163                 return -ENXIO;
1164         switch (cmd) {
1165         case SNDRV_CTL_IOCTL_PVERSION:
1166                 return put_user(SNDRV_CTL_VERSION, ip) ? -EFAULT : 0;
1167         case SNDRV_CTL_IOCTL_CARD_INFO:
1168                 return snd_ctl_card_info(card, ctl, cmd, argp);
1169         case SNDRV_CTL_IOCTL_ELEM_LIST:
1170                 return snd_ctl_elem_list(card, argp);
1171         case SNDRV_CTL_IOCTL_ELEM_INFO:
1172                 return snd_ctl_elem_info_user(ctl, argp);
1173         case SNDRV_CTL_IOCTL_ELEM_READ:
1174                 return snd_ctl_elem_read_user(card, argp);
1175         case SNDRV_CTL_IOCTL_ELEM_WRITE:
1176                 return snd_ctl_elem_write_user(ctl, argp);
1177         case SNDRV_CTL_IOCTL_ELEM_LOCK:
1178                 return snd_ctl_elem_lock(ctl, argp);
1179         case SNDRV_CTL_IOCTL_ELEM_UNLOCK:
1180                 return snd_ctl_elem_unlock(ctl, argp);
1181         case SNDRV_CTL_IOCTL_ELEM_ADD:
1182                 return snd_ctl_elem_add_user(ctl, argp, 0);
1183         case SNDRV_CTL_IOCTL_ELEM_REPLACE:
1184                 return snd_ctl_elem_add_user(ctl, argp, 1);
1185         case SNDRV_CTL_IOCTL_ELEM_REMOVE:
1186                 return snd_ctl_elem_remove(ctl, argp);
1187         case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS:
1188                 return snd_ctl_subscribe_events(ctl, ip);
1189         case SNDRV_CTL_IOCTL_TLV_READ:
1190                 return snd_ctl_tlv_ioctl(ctl, argp, 0);
1191         case SNDRV_CTL_IOCTL_TLV_WRITE:
1192                 return snd_ctl_tlv_ioctl(ctl, argp, 1);
1193         case SNDRV_CTL_IOCTL_TLV_COMMAND:
1194                 return snd_ctl_tlv_ioctl(ctl, argp, -1);
1195         case SNDRV_CTL_IOCTL_POWER:
1196                 return -ENOPROTOOPT;
1197         case SNDRV_CTL_IOCTL_POWER_STATE:
1198 #ifdef CONFIG_PM
1199                 return put_user(card->power_state, ip) ? -EFAULT : 0;
1200 #else
1201                 return put_user(SNDRV_CTL_POWER_D0, ip) ? -EFAULT : 0;
1202 #endif
1203         }
1204         down_read(&snd_ioctl_rwsem);
1205         list_for_each_entry(p, &snd_control_ioctls, list) {
1206                 err = p->fioctl(card, ctl, cmd, arg);
1207                 if (err != -ENOIOCTLCMD) {
1208                         up_read(&snd_ioctl_rwsem);
1209                         return err;
1210                 }
1211         }
1212         up_read(&snd_ioctl_rwsem);
1213         snd_printdd("unknown ioctl = 0x%x\n", cmd);
1214         return -ENOTTY;
1215 }
1216
1217 static ssize_t snd_ctl_read(struct file *file, char __user *buffer,
1218                             size_t count, loff_t * offset)
1219 {
1220         struct snd_ctl_file *ctl;
1221         int err = 0;
1222         ssize_t result = 0;
1223
1224         ctl = file->private_data;
1225         if (snd_BUG_ON(!ctl || !ctl->card))
1226                 return -ENXIO;
1227         if (!ctl->subscribed)
1228                 return -EBADFD;
1229         if (count < sizeof(struct snd_ctl_event))
1230                 return -EINVAL;
1231         spin_lock_irq(&ctl->read_lock);
1232         while (count >= sizeof(struct snd_ctl_event)) {
1233                 struct snd_ctl_event ev;
1234                 struct snd_kctl_event *kev;
1235                 while (list_empty(&ctl->events)) {
1236                         wait_queue_t wait;
1237                         if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) {
1238                                 err = -EAGAIN;
1239                                 goto __end_lock;
1240                         }
1241                         init_waitqueue_entry(&wait, current);
1242                         add_wait_queue(&ctl->change_sleep, &wait);
1243                         set_current_state(TASK_INTERRUPTIBLE);
1244                         spin_unlock_irq(&ctl->read_lock);
1245                         schedule();
1246                         remove_wait_queue(&ctl->change_sleep, &wait);
1247                         if (signal_pending(current))
1248                                 return -ERESTARTSYS;
1249                         spin_lock_irq(&ctl->read_lock);
1250                 }
1251                 kev = snd_kctl_event(ctl->events.next);
1252                 ev.type = SNDRV_CTL_EVENT_ELEM;
1253                 ev.data.elem.mask = kev->mask;
1254                 ev.data.elem.id = kev->id;
1255                 list_del(&kev->list);
1256                 spin_unlock_irq(&ctl->read_lock);
1257                 kfree(kev);
1258                 if (copy_to_user(buffer, &ev, sizeof(struct snd_ctl_event))) {
1259                         err = -EFAULT;
1260                         goto __end;
1261                 }
1262                 spin_lock_irq(&ctl->read_lock);
1263                 buffer += sizeof(struct snd_ctl_event);
1264                 count -= sizeof(struct snd_ctl_event);
1265                 result += sizeof(struct snd_ctl_event);
1266         }
1267       __end_lock:
1268         spin_unlock_irq(&ctl->read_lock);
1269       __end:
1270         return result > 0 ? result : err;
1271 }
1272
1273 static unsigned int snd_ctl_poll(struct file *file, poll_table * wait)
1274 {
1275         unsigned int mask;
1276         struct snd_ctl_file *ctl;
1277
1278         ctl = file->private_data;
1279         if (!ctl->subscribed)
1280                 return 0;
1281         poll_wait(file, &ctl->change_sleep, wait);
1282
1283         mask = 0;
1284         if (!list_empty(&ctl->events))
1285                 mask |= POLLIN | POLLRDNORM;
1286
1287         return mask;
1288 }
1289
1290 /*
1291  * register the device-specific control-ioctls.
1292  * called from each device manager like pcm.c, hwdep.c, etc.
1293  */
1294 static int _snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn, struct list_head *lists)
1295 {
1296         struct snd_kctl_ioctl *pn;
1297
1298         pn = kzalloc(sizeof(struct snd_kctl_ioctl), GFP_KERNEL);
1299         if (pn == NULL)
1300                 return -ENOMEM;
1301         pn->fioctl = fcn;
1302         down_write(&snd_ioctl_rwsem);
1303         list_add_tail(&pn->list, lists);
1304         up_write(&snd_ioctl_rwsem);
1305         return 0;
1306 }
1307
1308 int snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn)
1309 {
1310         return _snd_ctl_register_ioctl(fcn, &snd_control_ioctls);
1311 }
1312
1313 EXPORT_SYMBOL(snd_ctl_register_ioctl);
1314
1315 #ifdef CONFIG_COMPAT
1316 int snd_ctl_register_ioctl_compat(snd_kctl_ioctl_func_t fcn)
1317 {
1318         return _snd_ctl_register_ioctl(fcn, &snd_control_compat_ioctls);
1319 }
1320
1321 EXPORT_SYMBOL(snd_ctl_register_ioctl_compat);
1322 #endif
1323
1324 /*
1325  * de-register the device-specific control-ioctls.
1326  */
1327 static int _snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn,
1328                                      struct list_head *lists)
1329 {
1330         struct snd_kctl_ioctl *p;
1331
1332         if (snd_BUG_ON(!fcn))
1333                 return -EINVAL;
1334         down_write(&snd_ioctl_rwsem);
1335         list_for_each_entry(p, lists, list) {
1336                 if (p->fioctl == fcn) {
1337                         list_del(&p->list);
1338                         up_write(&snd_ioctl_rwsem);
1339                         kfree(p);
1340                         return 0;
1341                 }
1342         }
1343         up_write(&snd_ioctl_rwsem);
1344         snd_BUG();
1345         return -EINVAL;
1346 }
1347
1348 int snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn)
1349 {
1350         return _snd_ctl_unregister_ioctl(fcn, &snd_control_ioctls);
1351 }
1352
1353 EXPORT_SYMBOL(snd_ctl_unregister_ioctl);
1354
1355 #ifdef CONFIG_COMPAT
1356 int snd_ctl_unregister_ioctl_compat(snd_kctl_ioctl_func_t fcn)
1357 {
1358         return _snd_ctl_unregister_ioctl(fcn, &snd_control_compat_ioctls);
1359 }
1360
1361 EXPORT_SYMBOL(snd_ctl_unregister_ioctl_compat);
1362 #endif
1363
1364 static int snd_ctl_fasync(int fd, struct file * file, int on)
1365 {
1366         struct snd_ctl_file *ctl;
1367
1368         ctl = file->private_data;
1369         return fasync_helper(fd, file, on, &ctl->fasync);
1370 }
1371
1372 /*
1373  * ioctl32 compat
1374  */
1375 #ifdef CONFIG_COMPAT
1376 #include "control_compat.c"
1377 #else
1378 #define snd_ctl_ioctl_compat    NULL
1379 #endif
1380
1381 /*
1382  *  INIT PART
1383  */
1384
1385 static const struct file_operations snd_ctl_f_ops =
1386 {
1387         .owner =        THIS_MODULE,
1388         .read =         snd_ctl_read,
1389         .open =         snd_ctl_open,
1390         .release =      snd_ctl_release,
1391         .poll =         snd_ctl_poll,
1392         .unlocked_ioctl =       snd_ctl_ioctl,
1393         .compat_ioctl = snd_ctl_ioctl_compat,
1394         .fasync =       snd_ctl_fasync,
1395 };
1396
1397 /*
1398  * registration of the control device
1399  */
1400 static int snd_ctl_dev_register(struct snd_device *device)
1401 {
1402         struct snd_card *card = device->device_data;
1403         int err, cardnum;
1404         char name[16];
1405
1406         if (snd_BUG_ON(!card))
1407                 return -ENXIO;
1408         cardnum = card->number;
1409         if (snd_BUG_ON(cardnum < 0 || cardnum >= SNDRV_CARDS))
1410                 return -ENXIO;
1411         sprintf(name, "controlC%i", cardnum);
1412         if ((err = snd_register_device(SNDRV_DEVICE_TYPE_CONTROL, card, -1,
1413                                        &snd_ctl_f_ops, card, name)) < 0)
1414                 return err;
1415         return 0;
1416 }
1417
1418 /*
1419  * disconnection of the control device
1420  */
1421 static int snd_ctl_dev_disconnect(struct snd_device *device)
1422 {
1423         struct snd_card *card = device->device_data;
1424         struct snd_ctl_file *ctl;
1425         int err, cardnum;
1426
1427         if (snd_BUG_ON(!card))
1428                 return -ENXIO;
1429         cardnum = card->number;
1430         if (snd_BUG_ON(cardnum < 0 || cardnum >= SNDRV_CARDS))
1431                 return -ENXIO;
1432
1433         read_lock(&card->ctl_files_rwlock);
1434         list_for_each_entry(ctl, &card->ctl_files, list) {
1435                 wake_up(&ctl->change_sleep);
1436                 kill_fasync(&ctl->fasync, SIGIO, POLL_ERR);
1437         }
1438         read_unlock(&card->ctl_files_rwlock);
1439
1440         if ((err = snd_unregister_device(SNDRV_DEVICE_TYPE_CONTROL,
1441                                          card, -1)) < 0)
1442                 return err;
1443         return 0;
1444 }
1445
1446 /*
1447  * free all controls
1448  */
1449 static int snd_ctl_dev_free(struct snd_device *device)
1450 {
1451         struct snd_card *card = device->device_data;
1452         struct snd_kcontrol *control;
1453
1454         down_write(&card->controls_rwsem);
1455         while (!list_empty(&card->controls)) {
1456                 control = snd_kcontrol(card->controls.next);
1457                 snd_ctl_remove(card, control);
1458         }
1459         up_write(&card->controls_rwsem);
1460         return 0;
1461 }
1462
1463 /*
1464  * create control core:
1465  * called from init.c
1466  */
1467 int snd_ctl_create(struct snd_card *card)
1468 {
1469         static struct snd_device_ops ops = {
1470                 .dev_free = snd_ctl_dev_free,
1471                 .dev_register = snd_ctl_dev_register,
1472                 .dev_disconnect = snd_ctl_dev_disconnect,
1473         };
1474
1475         if (snd_BUG_ON(!card))
1476                 return -ENXIO;
1477         return snd_device_new(card, SNDRV_DEV_CONTROL, card, &ops);
1478 }
1479
1480 /*
1481  * Frequently used control callbacks
1482  */
1483 int snd_ctl_boolean_mono_info(struct snd_kcontrol *kcontrol,
1484                               struct snd_ctl_elem_info *uinfo)
1485 {
1486         uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
1487         uinfo->count = 1;
1488         uinfo->value.integer.min = 0;
1489         uinfo->value.integer.max = 1;
1490         return 0;
1491 }
1492
1493 EXPORT_SYMBOL(snd_ctl_boolean_mono_info);
1494
1495 int snd_ctl_boolean_stereo_info(struct snd_kcontrol *kcontrol,
1496                                 struct snd_ctl_elem_info *uinfo)
1497 {
1498         uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
1499         uinfo->count = 2;
1500         uinfo->value.integer.min = 0;
1501         uinfo->value.integer.max = 1;
1502         return 0;
1503 }
1504
1505 EXPORT_SYMBOL(snd_ctl_boolean_stereo_info);