Merge master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6 into next
[linux-2.6] / 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 = current->pid;
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         fasync_helper(-1, file, 0, &ctl->fasync);
117         file->private_data = NULL;
118         card = ctl->card;
119         write_lock_irqsave(&card->ctl_files_rwlock, flags);
120         list_del(&ctl->list);
121         write_unlock_irqrestore(&card->ctl_files_rwlock, flags);
122         down_write(&card->controls_rwsem);
123         list_for_each_entry(control, &card->controls, list)
124                 for (idx = 0; idx < control->count; idx++)
125                         if (control->vd[idx].owner == ctl)
126                                 control->vd[idx].owner = NULL;
127         up_write(&card->controls_rwsem);
128         snd_ctl_empty_read_queue(ctl);
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         snd_assert(card != NULL && id != NULL, return);
143         read_lock(&card->ctl_files_rwlock);
144 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
145         card->mixer_oss_change_count++;
146 #endif
147         list_for_each_entry(ctl, &card->ctl_files, list) {
148                 if (!ctl->subscribed)
149                         continue;
150                 spin_lock_irqsave(&ctl->read_lock, flags);
151                 list_for_each_entry(ev, &ctl->events, list) {
152                         if (ev->id.numid == id->numid) {
153                                 ev->mask |= mask;
154                                 goto _found;
155                         }
156                 }
157                 ev = kzalloc(sizeof(*ev), GFP_ATOMIC);
158                 if (ev) {
159                         ev->id = *id;
160                         ev->mask = mask;
161                         list_add_tail(&ev->list, &ctl->events);
162                 } else {
163                         snd_printk(KERN_ERR "No memory available to allocate event\n");
164                 }
165         _found:
166                 wake_up(&ctl->change_sleep);
167                 spin_unlock_irqrestore(&ctl->read_lock, flags);
168                 kill_fasync(&ctl->fasync, SIGIO, POLL_IN);
169         }
170         read_unlock(&card->ctl_files_rwlock);
171 }
172
173 EXPORT_SYMBOL(snd_ctl_notify);
174
175 /**
176  * snd_ctl_new - create a control instance from the template
177  * @control: the control template
178  * @access: the default control access
179  *
180  * Allocates a new struct snd_kcontrol instance and copies the given template 
181  * to the new instance. It does not copy volatile data (access).
182  *
183  * Returns the pointer of the new instance, or NULL on failure.
184  */
185 static struct snd_kcontrol *snd_ctl_new(struct snd_kcontrol *control,
186                                         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 /**
205  * snd_ctl_new1 - create a control instance from the template
206  * @ncontrol: the initialization record
207  * @private_data: the private data to set
208  *
209  * Allocates a new struct snd_kcontrol instance and initialize from the given 
210  * template.  When the access field of ncontrol is 0, it's assumed as
211  * READWRITE access. When the count field is 0, it's assumes as one.
212  *
213  * Returns the pointer of the newly generated instance, or NULL on failure.
214  */
215 struct snd_kcontrol *snd_ctl_new1(const struct snd_kcontrol_new *ncontrol,
216                                   void *private_data)
217 {
218         struct snd_kcontrol kctl;
219         unsigned int access;
220         
221         snd_assert(ncontrol != NULL, return NULL);
222         snd_assert(ncontrol->info != NULL, return NULL);
223         memset(&kctl, 0, sizeof(kctl));
224         kctl.id.iface = ncontrol->iface;
225         kctl.id.device = ncontrol->device;
226         kctl.id.subdevice = ncontrol->subdevice;
227         if (ncontrol->name)
228                 strlcpy(kctl.id.name, ncontrol->name, sizeof(kctl.id.name));
229         kctl.id.index = ncontrol->index;
230         kctl.count = ncontrol->count ? ncontrol->count : 1;
231         access = ncontrol->access == 0 ? SNDRV_CTL_ELEM_ACCESS_READWRITE :
232                  (ncontrol->access & (SNDRV_CTL_ELEM_ACCESS_READWRITE|
233                                       SNDRV_CTL_ELEM_ACCESS_INACTIVE|
234                                       SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE|
235                                       SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK));
236         kctl.info = ncontrol->info;
237         kctl.get = ncontrol->get;
238         kctl.put = ncontrol->put;
239         kctl.tlv.p = ncontrol->tlv.p;
240         kctl.private_value = ncontrol->private_value;
241         kctl.private_data = private_data;
242         return snd_ctl_new(&kctl, access);
243 }
244
245 EXPORT_SYMBOL(snd_ctl_new1);
246
247 /**
248  * snd_ctl_free_one - release the control instance
249  * @kcontrol: the control instance
250  *
251  * Releases the control instance created via snd_ctl_new()
252  * or snd_ctl_new1().
253  * Don't call this after the control was added to the card.
254  */
255 void snd_ctl_free_one(struct snd_kcontrol *kcontrol)
256 {
257         if (kcontrol) {
258                 if (kcontrol->private_free)
259                         kcontrol->private_free(kcontrol);
260                 kfree(kcontrol);
261         }
262 }
263
264 EXPORT_SYMBOL(snd_ctl_free_one);
265
266 static unsigned int snd_ctl_hole_check(struct snd_card *card,
267                                        unsigned int count)
268 {
269         struct snd_kcontrol *kctl;
270
271         list_for_each_entry(kctl, &card->controls, list) {
272                 if ((kctl->id.numid <= card->last_numid &&
273                      kctl->id.numid + kctl->count > card->last_numid) ||
274                     (kctl->id.numid <= card->last_numid + count - 1 &&
275                      kctl->id.numid + kctl->count > card->last_numid + count - 1))
276                         return card->last_numid = kctl->id.numid + kctl->count - 1;
277         }
278         return card->last_numid;
279 }
280
281 static int snd_ctl_find_hole(struct snd_card *card, unsigned int count)
282 {
283         unsigned int last_numid, iter = 100000;
284
285         last_numid = card->last_numid;
286         while (last_numid != snd_ctl_hole_check(card, count)) {
287                 if (--iter == 0) {
288                         /* this situation is very unlikely */
289                         snd_printk(KERN_ERR "unable to allocate new control numid\n");
290                         return -ENOMEM;
291                 }
292                 last_numid = card->last_numid;
293         }
294         return 0;
295 }
296
297 /**
298  * snd_ctl_add - add the control instance to the card
299  * @card: the card instance
300  * @kcontrol: the control instance to add
301  *
302  * Adds the control instance created via snd_ctl_new() or
303  * snd_ctl_new1() to the given card. Assigns also an unique
304  * numid used for fast search.
305  *
306  * Returns zero if successful, or a negative error code on failure.
307  *
308  * It frees automatically the control which cannot be added.
309  */
310 int snd_ctl_add(struct snd_card *card, struct snd_kcontrol *kcontrol)
311 {
312         struct snd_ctl_elem_id id;
313         unsigned int idx;
314         int err = -EINVAL;
315
316         if (! kcontrol)
317                 return err;
318         snd_assert(card != NULL, goto error);
319         snd_assert(kcontrol->info != NULL, goto error);
320         id = kcontrol->id;
321         down_write(&card->controls_rwsem);
322         if (snd_ctl_find_id(card, &id)) {
323                 up_write(&card->controls_rwsem);
324                 snd_printd(KERN_ERR "control %i:%i:%i:%s:%i is already present\n",
325                                         id.iface,
326                                         id.device,
327                                         id.subdevice,
328                                         id.name,
329                                         id.index);
330                 err = -EBUSY;
331                 goto error;
332         }
333         if (snd_ctl_find_hole(card, kcontrol->count) < 0) {
334                 up_write(&card->controls_rwsem);
335                 err = -ENOMEM;
336                 goto error;
337         }
338         list_add_tail(&kcontrol->list, &card->controls);
339         card->controls_count += kcontrol->count;
340         kcontrol->id.numid = card->last_numid + 1;
341         card->last_numid += kcontrol->count;
342         up_write(&card->controls_rwsem);
343         for (idx = 0; idx < kcontrol->count; idx++, id.index++, id.numid++)
344                 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_ADD, &id);
345         return 0;
346
347  error:
348         snd_ctl_free_one(kcontrol);
349         return err;
350 }
351
352 EXPORT_SYMBOL(snd_ctl_add);
353
354 /**
355  * snd_ctl_remove - remove the control from the card and release it
356  * @card: the card instance
357  * @kcontrol: the control instance to remove
358  *
359  * Removes the control from the card and then releases the instance.
360  * You don't need to call snd_ctl_free_one(). You must be in
361  * the write lock - down_write(&card->controls_rwsem).
362  * 
363  * Returns 0 if successful, or a negative error code on failure.
364  */
365 int snd_ctl_remove(struct snd_card *card, struct snd_kcontrol *kcontrol)
366 {
367         struct snd_ctl_elem_id id;
368         unsigned int idx;
369
370         snd_assert(card != NULL && kcontrol != NULL, return -EINVAL);
371         list_del(&kcontrol->list);
372         card->controls_count -= kcontrol->count;
373         id = kcontrol->id;
374         for (idx = 0; idx < kcontrol->count; idx++, id.index++, id.numid++)
375                 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_REMOVE, &id);
376         snd_ctl_free_one(kcontrol);
377         return 0;
378 }
379
380 EXPORT_SYMBOL(snd_ctl_remove);
381
382 /**
383  * snd_ctl_remove_id - remove the control of the given id and release it
384  * @card: the card instance
385  * @id: the control id to remove
386  *
387  * Finds the control instance with the given id, removes it from the
388  * card list and releases it.
389  * 
390  * Returns 0 if successful, or a negative error code on failure.
391  */
392 int snd_ctl_remove_id(struct snd_card *card, struct snd_ctl_elem_id *id)
393 {
394         struct snd_kcontrol *kctl;
395         int ret;
396
397         down_write(&card->controls_rwsem);
398         kctl = snd_ctl_find_id(card, id);
399         if (kctl == NULL) {
400                 up_write(&card->controls_rwsem);
401                 return -ENOENT;
402         }
403         ret = snd_ctl_remove(card, kctl);
404         up_write(&card->controls_rwsem);
405         return ret;
406 }
407
408 EXPORT_SYMBOL(snd_ctl_remove_id);
409
410 /**
411  * snd_ctl_remove_unlocked_id - remove the unlocked control of the given id and release it
412  * @file: active control handle
413  * @id: the control id to remove
414  *
415  * Finds the control instance with the given id, removes it from the
416  * card list and releases it.
417  * 
418  * Returns 0 if successful, or a negative error code on failure.
419  */
420 static int snd_ctl_remove_unlocked_id(struct snd_ctl_file * file,
421                                       struct snd_ctl_elem_id *id)
422 {
423         struct snd_card *card = file->card;
424         struct snd_kcontrol *kctl;
425         int idx, ret;
426
427         down_write(&card->controls_rwsem);
428         kctl = snd_ctl_find_id(card, id);
429         if (kctl == NULL) {
430                 up_write(&card->controls_rwsem);
431                 return -ENOENT;
432         }
433         for (idx = 0; idx < kctl->count; idx++)
434                 if (kctl->vd[idx].owner != NULL && kctl->vd[idx].owner != file) {
435                         up_write(&card->controls_rwsem);
436                         return -EBUSY;
437                 }
438         ret = snd_ctl_remove(card, kctl);
439         up_write(&card->controls_rwsem);
440         return ret;
441 }
442
443 /**
444  * snd_ctl_rename_id - replace the id of a control on the card
445  * @card: the card instance
446  * @src_id: the old id
447  * @dst_id: the new id
448  *
449  * Finds the control with the old id from the card, and replaces the
450  * id with the new one.
451  *
452  * Returns zero if successful, or a negative error code on failure.
453  */
454 int snd_ctl_rename_id(struct snd_card *card, struct snd_ctl_elem_id *src_id,
455                       struct snd_ctl_elem_id *dst_id)
456 {
457         struct snd_kcontrol *kctl;
458
459         down_write(&card->controls_rwsem);
460         kctl = snd_ctl_find_id(card, src_id);
461         if (kctl == NULL) {
462                 up_write(&card->controls_rwsem);
463                 return -ENOENT;
464         }
465         kctl->id = *dst_id;
466         kctl->id.numid = card->last_numid + 1;
467         card->last_numid += kctl->count;
468         up_write(&card->controls_rwsem);
469         return 0;
470 }
471
472 EXPORT_SYMBOL(snd_ctl_rename_id);
473
474 /**
475  * snd_ctl_find_numid - find the control instance with the given number-id
476  * @card: the card instance
477  * @numid: the number-id to search
478  *
479  * Finds the control instance with the given number-id from the card.
480  *
481  * Returns the pointer of the instance if found, or NULL if not.
482  *
483  * The caller must down card->controls_rwsem before calling this function
484  * (if the race condition can happen).
485  */
486 struct snd_kcontrol *snd_ctl_find_numid(struct snd_card *card, unsigned int numid)
487 {
488         struct snd_kcontrol *kctl;
489
490         snd_assert(card != NULL && numid != 0, return NULL);
491         list_for_each_entry(kctl, &card->controls, list) {
492                 if (kctl->id.numid <= numid && kctl->id.numid + kctl->count > numid)
493                         return kctl;
494         }
495         return NULL;
496 }
497
498 EXPORT_SYMBOL(snd_ctl_find_numid);
499
500 /**
501  * snd_ctl_find_id - find the control instance with the given id
502  * @card: the card instance
503  * @id: the id to search
504  *
505  * Finds the control instance with the given id from the card.
506  *
507  * Returns the pointer of the instance if found, or NULL if not.
508  *
509  * The caller must down card->controls_rwsem before calling this function
510  * (if the race condition can happen).
511  */
512 struct snd_kcontrol *snd_ctl_find_id(struct snd_card *card,
513                                      struct snd_ctl_elem_id *id)
514 {
515         struct snd_kcontrol *kctl;
516
517         snd_assert(card != NULL && id != NULL, return NULL);
518         if (id->numid != 0)
519                 return snd_ctl_find_numid(card, id->numid);
520         list_for_each_entry(kctl, &card->controls, list) {
521                 if (kctl->id.iface != id->iface)
522                         continue;
523                 if (kctl->id.device != id->device)
524                         continue;
525                 if (kctl->id.subdevice != id->subdevice)
526                         continue;
527                 if (strncmp(kctl->id.name, id->name, sizeof(kctl->id.name)))
528                         continue;
529                 if (kctl->id.index > id->index)
530                         continue;
531                 if (kctl->id.index + kctl->count <= id->index)
532                         continue;
533                 return kctl;
534         }
535         return NULL;
536 }
537
538 EXPORT_SYMBOL(snd_ctl_find_id);
539
540 static int snd_ctl_card_info(struct snd_card *card, struct snd_ctl_file * ctl,
541                              unsigned int cmd, void __user *arg)
542 {
543         struct snd_ctl_card_info *info;
544
545         info = kzalloc(sizeof(*info), GFP_KERNEL);
546         if (! info)
547                 return -ENOMEM;
548         down_read(&snd_ioctl_rwsem);
549         info->card = card->number;
550         strlcpy(info->id, card->id, sizeof(info->id));
551         strlcpy(info->driver, card->driver, sizeof(info->driver));
552         strlcpy(info->name, card->shortname, sizeof(info->name));
553         strlcpy(info->longname, card->longname, sizeof(info->longname));
554         strlcpy(info->mixername, card->mixername, sizeof(info->mixername));
555         strlcpy(info->components, card->components, sizeof(info->components));
556         up_read(&snd_ioctl_rwsem);
557         if (copy_to_user(arg, info, sizeof(struct snd_ctl_card_info))) {
558                 kfree(info);
559                 return -EFAULT;
560         }
561         kfree(info);
562         return 0;
563 }
564
565 static int snd_ctl_elem_list(struct snd_card *card,
566                              struct snd_ctl_elem_list __user *_list)
567 {
568         struct list_head *plist;
569         struct snd_ctl_elem_list list;
570         struct snd_kcontrol *kctl;
571         struct snd_ctl_elem_id *dst, *id;
572         unsigned int offset, space, first, jidx;
573         
574         if (copy_from_user(&list, _list, sizeof(list)))
575                 return -EFAULT;
576         offset = list.offset;
577         space = list.space;
578         first = 0;
579         /* try limit maximum space */
580         if (space > 16384)
581                 return -ENOMEM;
582         if (space > 0) {
583                 /* allocate temporary buffer for atomic operation */
584                 dst = vmalloc(space * sizeof(struct snd_ctl_elem_id));
585                 if (dst == NULL)
586                         return -ENOMEM;
587                 down_read(&card->controls_rwsem);
588                 list.count = card->controls_count;
589                 plist = card->controls.next;
590                 while (plist != &card->controls) {
591                         if (offset == 0)
592                                 break;
593                         kctl = snd_kcontrol(plist);
594                         if (offset < kctl->count)
595                                 break;
596                         offset -= kctl->count;
597                         plist = plist->next;
598                 }
599                 list.used = 0;
600                 id = dst;
601                 while (space > 0 && plist != &card->controls) {
602                         kctl = snd_kcontrol(plist);
603                         for (jidx = offset; space > 0 && jidx < kctl->count; jidx++) {
604                                 snd_ctl_build_ioff(id, kctl, jidx);
605                                 id++;
606                                 space--;
607                                 list.used++;
608                         }
609                         plist = plist->next;
610                         offset = 0;
611                 }
612                 up_read(&card->controls_rwsem);
613                 if (list.used > 0 &&
614                     copy_to_user(list.pids, dst,
615                                  list.used * sizeof(struct snd_ctl_elem_id))) {
616                         vfree(dst);
617                         return -EFAULT;
618                 }
619                 vfree(dst);
620         } else {
621                 down_read(&card->controls_rwsem);
622                 list.count = card->controls_count;
623                 up_read(&card->controls_rwsem);
624         }
625         if (copy_to_user(_list, &list, sizeof(list)))
626                 return -EFAULT;
627         return 0;
628 }
629
630 static int snd_ctl_elem_info(struct snd_ctl_file *ctl,
631                              struct snd_ctl_elem_info *info)
632 {
633         struct snd_card *card = ctl->card;
634         struct snd_kcontrol *kctl;
635         struct snd_kcontrol_volatile *vd;
636         unsigned int index_offset;
637         int result;
638         
639         down_read(&card->controls_rwsem);
640         kctl = snd_ctl_find_id(card, &info->id);
641         if (kctl == NULL) {
642                 up_read(&card->controls_rwsem);
643                 return -ENOENT;
644         }
645 #ifdef CONFIG_SND_DEBUG
646         info->access = 0;
647 #endif
648         result = kctl->info(kctl, info);
649         if (result >= 0) {
650                 snd_assert(info->access == 0, );
651                 index_offset = snd_ctl_get_ioff(kctl, &info->id);
652                 vd = &kctl->vd[index_offset];
653                 snd_ctl_build_ioff(&info->id, kctl, index_offset);
654                 info->access = vd->access;
655                 if (vd->owner) {
656                         info->access |= SNDRV_CTL_ELEM_ACCESS_LOCK;
657                         if (vd->owner == ctl)
658                                 info->access |= SNDRV_CTL_ELEM_ACCESS_OWNER;
659                         info->owner = vd->owner_pid;
660                 } else {
661                         info->owner = -1;
662                 }
663         }
664         up_read(&card->controls_rwsem);
665         return result;
666 }
667
668 static int snd_ctl_elem_info_user(struct snd_ctl_file *ctl,
669                                   struct snd_ctl_elem_info __user *_info)
670 {
671         struct snd_ctl_elem_info info;
672         int result;
673
674         if (copy_from_user(&info, _info, sizeof(info)))
675                 return -EFAULT;
676         snd_power_lock(ctl->card);
677         result = snd_power_wait(ctl->card, SNDRV_CTL_POWER_D0);
678         if (result >= 0)
679                 result = snd_ctl_elem_info(ctl, &info);
680         snd_power_unlock(ctl->card);
681         if (result >= 0)
682                 if (copy_to_user(_info, &info, sizeof(info)))
683                         return -EFAULT;
684         return result;
685 }
686
687 static int snd_ctl_elem_read(struct snd_card *card,
688                              struct snd_ctl_elem_value *control)
689 {
690         struct snd_kcontrol *kctl;
691         struct snd_kcontrol_volatile *vd;
692         unsigned int index_offset;
693         int result;
694
695         down_read(&card->controls_rwsem);
696         kctl = snd_ctl_find_id(card, &control->id);
697         if (kctl == NULL) {
698                 result = -ENOENT;
699         } else {
700                 index_offset = snd_ctl_get_ioff(kctl, &control->id);
701                 vd = &kctl->vd[index_offset];
702                 if ((vd->access & SNDRV_CTL_ELEM_ACCESS_READ) &&
703                     kctl->get != NULL) {
704                         snd_ctl_build_ioff(&control->id, kctl, index_offset);
705                         result = kctl->get(kctl, control);
706                 } else
707                         result = -EPERM;
708         }
709         up_read(&card->controls_rwsem);
710         return result;
711 }
712
713 static int snd_ctl_elem_read_user(struct snd_card *card,
714                                   struct snd_ctl_elem_value __user *_control)
715 {
716         struct snd_ctl_elem_value *control;
717         int result;
718         
719         control = kmalloc(sizeof(*control), GFP_KERNEL);
720         if (control == NULL)
721                 return -ENOMEM; 
722         if (copy_from_user(control, _control, sizeof(*control))) {
723                 kfree(control);
724                 return -EFAULT;
725         }
726         snd_power_lock(card);
727         result = snd_power_wait(card, SNDRV_CTL_POWER_D0);
728         if (result >= 0)
729                 result = snd_ctl_elem_read(card, control);
730         snd_power_unlock(card);
731         if (result >= 0)
732                 if (copy_to_user(_control, control, sizeof(*control)))
733                         result = -EFAULT;
734         kfree(control);
735         return result;
736 }
737
738 static int snd_ctl_elem_write(struct snd_card *card, struct snd_ctl_file *file,
739                               struct snd_ctl_elem_value *control)
740 {
741         struct snd_kcontrol *kctl;
742         struct snd_kcontrol_volatile *vd;
743         unsigned int index_offset;
744         int result;
745
746         down_read(&card->controls_rwsem);
747         kctl = snd_ctl_find_id(card, &control->id);
748         if (kctl == NULL) {
749                 result = -ENOENT;
750         } else {
751                 index_offset = snd_ctl_get_ioff(kctl, &control->id);
752                 vd = &kctl->vd[index_offset];
753                 if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_WRITE) ||
754                     kctl->put == NULL ||
755                     (file && vd->owner && vd->owner != file)) {
756                         result = -EPERM;
757                 } else {
758                         snd_ctl_build_ioff(&control->id, kctl, index_offset);
759                         result = kctl->put(kctl, control);
760                 }
761                 if (result > 0) {
762                         up_read(&card->controls_rwsem);
763                         snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
764                                        &control->id);
765                         return 0;
766                 }
767         }
768         up_read(&card->controls_rwsem);
769         return result;
770 }
771
772 static int snd_ctl_elem_write_user(struct snd_ctl_file *file,
773                                    struct snd_ctl_elem_value __user *_control)
774 {
775         struct snd_ctl_elem_value *control;
776         struct snd_card *card;
777         int result;
778
779         control = kmalloc(sizeof(*control), GFP_KERNEL);
780         if (control == NULL)
781                 return -ENOMEM; 
782         if (copy_from_user(control, _control, sizeof(*control))) {
783                 kfree(control);
784                 return -EFAULT;
785         }
786         card = file->card;
787         snd_power_lock(card);
788         result = snd_power_wait(card, SNDRV_CTL_POWER_D0);
789         if (result >= 0)
790                 result = snd_ctl_elem_write(card, file, control);
791         snd_power_unlock(card);
792         if (result >= 0)
793                 if (copy_to_user(_control, control, sizeof(*control)))
794                         result = -EFAULT;
795         kfree(control);
796         return result;
797 }
798
799 static int snd_ctl_elem_lock(struct snd_ctl_file *file,
800                              struct snd_ctl_elem_id __user *_id)
801 {
802         struct snd_card *card = file->card;
803         struct snd_ctl_elem_id id;
804         struct snd_kcontrol *kctl;
805         struct snd_kcontrol_volatile *vd;
806         int result;
807         
808         if (copy_from_user(&id, _id, sizeof(id)))
809                 return -EFAULT;
810         down_write(&card->controls_rwsem);
811         kctl = snd_ctl_find_id(card, &id);
812         if (kctl == NULL) {
813                 result = -ENOENT;
814         } else {
815                 vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)];
816                 if (vd->owner != NULL)
817                         result = -EBUSY;
818                 else {
819                         vd->owner = file;
820                         vd->owner_pid = current->pid;
821                         result = 0;
822                 }
823         }
824         up_write(&card->controls_rwsem);
825         return result;
826 }
827
828 static int snd_ctl_elem_unlock(struct snd_ctl_file *file,
829                                struct snd_ctl_elem_id __user *_id)
830 {
831         struct snd_card *card = file->card;
832         struct snd_ctl_elem_id id;
833         struct snd_kcontrol *kctl;
834         struct snd_kcontrol_volatile *vd;
835         int result;
836         
837         if (copy_from_user(&id, _id, sizeof(id)))
838                 return -EFAULT;
839         down_write(&card->controls_rwsem);
840         kctl = snd_ctl_find_id(card, &id);
841         if (kctl == NULL) {
842                 result = -ENOENT;
843         } else {
844                 vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)];
845                 if (vd->owner == NULL)
846                         result = -EINVAL;
847                 else if (vd->owner != file)
848                         result = -EPERM;
849                 else {
850                         vd->owner = NULL;
851                         vd->owner_pid = 0;
852                         result = 0;
853                 }
854         }
855         up_write(&card->controls_rwsem);
856         return result;
857 }
858
859 struct user_element {
860         struct snd_ctl_elem_info info;
861         void *elem_data;                /* element data */
862         unsigned long elem_data_size;   /* size of element data in bytes */
863         void *tlv_data;                 /* TLV data */
864         unsigned long tlv_data_size;    /* TLV data size */
865         void *priv_data;                /* private data (like strings for enumerated type) */
866         unsigned long priv_data_size;   /* size of private data in bytes */
867 };
868
869 static int snd_ctl_elem_user_info(struct snd_kcontrol *kcontrol,
870                                   struct snd_ctl_elem_info *uinfo)
871 {
872         struct user_element *ue = kcontrol->private_data;
873
874         *uinfo = ue->info;
875         return 0;
876 }
877
878 static int snd_ctl_elem_user_get(struct snd_kcontrol *kcontrol,
879                                  struct snd_ctl_elem_value *ucontrol)
880 {
881         struct user_element *ue = kcontrol->private_data;
882
883         memcpy(&ucontrol->value, ue->elem_data, ue->elem_data_size);
884         return 0;
885 }
886
887 static int snd_ctl_elem_user_put(struct snd_kcontrol *kcontrol,
888                                  struct snd_ctl_elem_value *ucontrol)
889 {
890         int change;
891         struct user_element *ue = kcontrol->private_data;
892         
893         change = memcmp(&ucontrol->value, ue->elem_data, ue->elem_data_size) != 0;
894         if (change)
895                 memcpy(ue->elem_data, &ucontrol->value, ue->elem_data_size);
896         return change;
897 }
898
899 static int snd_ctl_elem_user_tlv(struct snd_kcontrol *kcontrol,
900                                  int op_flag,
901                                  unsigned int size,
902                                  unsigned int __user *tlv)
903 {
904         struct user_element *ue = kcontrol->private_data;
905         int change = 0;
906         void *new_data;
907
908         if (op_flag > 0) {
909                 if (size > 1024 * 128)  /* sane value */
910                         return -EINVAL;
911                 new_data = kmalloc(size, GFP_KERNEL);
912                 if (new_data == NULL)
913                         return -ENOMEM;
914                 if (copy_from_user(new_data, tlv, size)) {
915                         kfree(new_data);
916                         return -EFAULT;
917                 }
918                 change = ue->tlv_data_size != size;
919                 if (!change)
920                         change = memcmp(ue->tlv_data, new_data, size);
921                 kfree(ue->tlv_data);
922                 ue->tlv_data = new_data;
923                 ue->tlv_data_size = size;
924         } else {
925                 if (! ue->tlv_data_size || ! ue->tlv_data)
926                         return -ENXIO;
927                 if (size < ue->tlv_data_size)
928                         return -ENOSPC;
929                 if (copy_to_user(tlv, ue->tlv_data, ue->tlv_data_size))
930                         return -EFAULT;
931         }
932         return change;
933 }
934
935 static void snd_ctl_elem_user_free(struct snd_kcontrol *kcontrol)
936 {
937         struct user_element *ue = kcontrol->private_data;
938         if (ue->tlv_data)
939                 kfree(ue->tlv_data);
940         kfree(ue);
941 }
942
943 static int snd_ctl_elem_add(struct snd_ctl_file *file,
944                             struct snd_ctl_elem_info *info, int replace)
945 {
946         struct snd_card *card = file->card;
947         struct snd_kcontrol kctl, *_kctl;
948         unsigned int access;
949         long private_size;
950         struct user_element *ue;
951         int idx, err;
952         
953         if (card->user_ctl_count >= MAX_USER_CONTROLS)
954                 return -ENOMEM;
955         if (info->count > 1024)
956                 return -EINVAL;
957         access = info->access == 0 ? SNDRV_CTL_ELEM_ACCESS_READWRITE :
958                 (info->access & (SNDRV_CTL_ELEM_ACCESS_READWRITE|
959                                  SNDRV_CTL_ELEM_ACCESS_INACTIVE|
960                                  SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE));
961         info->id.numid = 0;
962         memset(&kctl, 0, sizeof(kctl));
963         down_write(&card->controls_rwsem);
964         _kctl = snd_ctl_find_id(card, &info->id);
965         err = 0;
966         if (_kctl) {
967                 if (replace)
968                         err = snd_ctl_remove(card, _kctl);
969                 else
970                         err = -EBUSY;
971         } else {
972                 if (replace)
973                         err = -ENOENT;
974         }
975         up_write(&card->controls_rwsem);
976         if (err < 0)
977                 return err;
978         memcpy(&kctl.id, &info->id, sizeof(info->id));
979         kctl.count = info->owner ? info->owner : 1;
980         access |= SNDRV_CTL_ELEM_ACCESS_USER;
981         kctl.info = snd_ctl_elem_user_info;
982         if (access & SNDRV_CTL_ELEM_ACCESS_READ)
983                 kctl.get = snd_ctl_elem_user_get;
984         if (access & SNDRV_CTL_ELEM_ACCESS_WRITE)
985                 kctl.put = snd_ctl_elem_user_put;
986         if (access & SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE) {
987                 kctl.tlv.c = snd_ctl_elem_user_tlv;
988                 access |= SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
989         }
990         switch (info->type) {
991         case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
992         case SNDRV_CTL_ELEM_TYPE_INTEGER:
993                 private_size = sizeof(long);
994                 if (info->count > 128)
995                         return -EINVAL;
996                 break;
997         case SNDRV_CTL_ELEM_TYPE_INTEGER64:
998                 private_size = sizeof(long long);
999                 if (info->count > 64)
1000                         return -EINVAL;
1001                 break;
1002         case SNDRV_CTL_ELEM_TYPE_BYTES:
1003                 private_size = sizeof(unsigned char);
1004                 if (info->count > 512)
1005                         return -EINVAL;
1006                 break;
1007         case SNDRV_CTL_ELEM_TYPE_IEC958:
1008                 private_size = sizeof(struct snd_aes_iec958);
1009                 if (info->count != 1)
1010                         return -EINVAL;
1011                 break;
1012         default:
1013                 return -EINVAL;
1014         }
1015         private_size *= info->count;
1016         ue = kzalloc(sizeof(struct user_element) + private_size, GFP_KERNEL);
1017         if (ue == NULL)
1018                 return -ENOMEM;
1019         ue->info = *info;
1020         ue->info.access = 0;
1021         ue->elem_data = (char *)ue + sizeof(*ue);
1022         ue->elem_data_size = private_size;
1023         kctl.private_free = snd_ctl_elem_user_free;
1024         _kctl = snd_ctl_new(&kctl, access);
1025         if (_kctl == NULL) {
1026                 kfree(ue);
1027                 return -ENOMEM;
1028         }
1029         _kctl->private_data = ue;
1030         for (idx = 0; idx < _kctl->count; idx++)
1031                 _kctl->vd[idx].owner = file;
1032         err = snd_ctl_add(card, _kctl);
1033         if (err < 0)
1034                 return err;
1035
1036         down_write(&card->controls_rwsem);
1037         card->user_ctl_count++;
1038         up_write(&card->controls_rwsem);
1039
1040         return 0;
1041 }
1042
1043 static int snd_ctl_elem_add_user(struct snd_ctl_file *file,
1044                                  struct snd_ctl_elem_info __user *_info, int replace)
1045 {
1046         struct snd_ctl_elem_info info;
1047         if (copy_from_user(&info, _info, sizeof(info)))
1048                 return -EFAULT;
1049         return snd_ctl_elem_add(file, &info, replace);
1050 }
1051
1052 static int snd_ctl_elem_remove(struct snd_ctl_file *file,
1053                                struct snd_ctl_elem_id __user *_id)
1054 {
1055         struct snd_ctl_elem_id id;
1056         int err;
1057
1058         if (copy_from_user(&id, _id, sizeof(id)))
1059                 return -EFAULT;
1060         err = snd_ctl_remove_unlocked_id(file, &id);
1061         if (! err) {
1062                 struct snd_card *card = file->card;
1063                 down_write(&card->controls_rwsem);
1064                 card->user_ctl_count--;
1065                 up_write(&card->controls_rwsem);
1066         }
1067         return err;
1068 }
1069
1070 static int snd_ctl_subscribe_events(struct snd_ctl_file *file, int __user *ptr)
1071 {
1072         int subscribe;
1073         if (get_user(subscribe, ptr))
1074                 return -EFAULT;
1075         if (subscribe < 0) {
1076                 subscribe = file->subscribed;
1077                 if (put_user(subscribe, ptr))
1078                         return -EFAULT;
1079                 return 0;
1080         }
1081         if (subscribe) {
1082                 file->subscribed = 1;
1083                 return 0;
1084         } else if (file->subscribed) {
1085                 snd_ctl_empty_read_queue(file);
1086                 file->subscribed = 0;
1087         }
1088         return 0;
1089 }
1090
1091 static int snd_ctl_tlv_ioctl(struct snd_ctl_file *file,
1092                              struct snd_ctl_tlv __user *_tlv,
1093                              int op_flag)
1094 {
1095         struct snd_card *card = file->card;
1096         struct snd_ctl_tlv tlv;
1097         struct snd_kcontrol *kctl;
1098         struct snd_kcontrol_volatile *vd;
1099         unsigned int len;
1100         int err = 0;
1101
1102         if (copy_from_user(&tlv, _tlv, sizeof(tlv)))
1103                 return -EFAULT;
1104         if (tlv.length < sizeof(unsigned int) * 3)
1105                 return -EINVAL;
1106         down_read(&card->controls_rwsem);
1107         kctl = snd_ctl_find_numid(card, tlv.numid);
1108         if (kctl == NULL) {
1109                 err = -ENOENT;
1110                 goto __kctl_end;
1111         }
1112         if (kctl->tlv.p == NULL) {
1113                 err = -ENXIO;
1114                 goto __kctl_end;
1115         }
1116         vd = &kctl->vd[tlv.numid - kctl->id.numid];
1117         if ((op_flag == 0 && (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_READ) == 0) ||
1118             (op_flag > 0 && (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_WRITE) == 0) ||
1119             (op_flag < 0 && (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND) == 0)) {
1120                 err = -ENXIO;
1121                 goto __kctl_end;
1122         }
1123         if (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK) {
1124                 if (file && vd->owner != NULL && vd->owner != file) {
1125                         err = -EPERM;
1126                         goto __kctl_end;
1127                 }
1128                 err = kctl->tlv.c(kctl, op_flag, tlv.length, _tlv->tlv); 
1129                 if (err > 0) {
1130                         up_read(&card->controls_rwsem);
1131                         snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_TLV, &kctl->id);
1132                         return 0;
1133                 }
1134         } else {
1135                 if (op_flag) {
1136                         err = -ENXIO;
1137                         goto __kctl_end;
1138                 }
1139                 len = kctl->tlv.p[1] + 2 * sizeof(unsigned int);
1140                 if (tlv.length < len) {
1141                         err = -ENOMEM;
1142                         goto __kctl_end;
1143                 }
1144                 if (copy_to_user(_tlv->tlv, kctl->tlv.p, len))
1145                         err = -EFAULT;
1146         }
1147       __kctl_end:
1148         up_read(&card->controls_rwsem);
1149         return err;
1150 }
1151
1152 static long snd_ctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1153 {
1154         struct snd_ctl_file *ctl;
1155         struct snd_card *card;
1156         struct snd_kctl_ioctl *p;
1157         void __user *argp = (void __user *)arg;
1158         int __user *ip = argp;
1159         int err;
1160
1161         ctl = file->private_data;
1162         card = ctl->card;
1163         snd_assert(card != NULL, 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         snd_assert(ctl != NULL && ctl->card != NULL, return -ENXIO);
1226         if (!ctl->subscribed)
1227                 return -EBADFD;
1228         if (count < sizeof(struct snd_ctl_event))
1229                 return -EINVAL;
1230         spin_lock_irq(&ctl->read_lock);
1231         while (count >= sizeof(struct snd_ctl_event)) {
1232                 struct snd_ctl_event ev;
1233                 struct snd_kctl_event *kev;
1234                 while (list_empty(&ctl->events)) {
1235                         wait_queue_t wait;
1236                         if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) {
1237                                 err = -EAGAIN;
1238                                 goto __end_lock;
1239                         }
1240                         init_waitqueue_entry(&wait, current);
1241                         add_wait_queue(&ctl->change_sleep, &wait);
1242                         set_current_state(TASK_INTERRUPTIBLE);
1243                         spin_unlock_irq(&ctl->read_lock);
1244                         schedule();
1245                         remove_wait_queue(&ctl->change_sleep, &wait);
1246                         if (signal_pending(current))
1247                                 return -ERESTARTSYS;
1248                         spin_lock_irq(&ctl->read_lock);
1249                 }
1250                 kev = snd_kctl_event(ctl->events.next);
1251                 ev.type = SNDRV_CTL_EVENT_ELEM;
1252                 ev.data.elem.mask = kev->mask;
1253                 ev.data.elem.id = kev->id;
1254                 list_del(&kev->list);
1255                 spin_unlock_irq(&ctl->read_lock);
1256                 kfree(kev);
1257                 if (copy_to_user(buffer, &ev, sizeof(struct snd_ctl_event))) {
1258                         err = -EFAULT;
1259                         goto __end;
1260                 }
1261                 spin_lock_irq(&ctl->read_lock);
1262                 buffer += sizeof(struct snd_ctl_event);
1263                 count -= sizeof(struct snd_ctl_event);
1264                 result += sizeof(struct snd_ctl_event);
1265         }
1266       __end_lock:
1267         spin_unlock_irq(&ctl->read_lock);
1268       __end:
1269         return result > 0 ? result : err;
1270 }
1271
1272 static unsigned int snd_ctl_poll(struct file *file, poll_table * wait)
1273 {
1274         unsigned int mask;
1275         struct snd_ctl_file *ctl;
1276
1277         ctl = file->private_data;
1278         if (!ctl->subscribed)
1279                 return 0;
1280         poll_wait(file, &ctl->change_sleep, wait);
1281
1282         mask = 0;
1283         if (!list_empty(&ctl->events))
1284                 mask |= POLLIN | POLLRDNORM;
1285
1286         return mask;
1287 }
1288
1289 /*
1290  * register the device-specific control-ioctls.
1291  * called from each device manager like pcm.c, hwdep.c, etc.
1292  */
1293 static int _snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn, struct list_head *lists)
1294 {
1295         struct snd_kctl_ioctl *pn;
1296
1297         pn = kzalloc(sizeof(struct snd_kctl_ioctl), GFP_KERNEL);
1298         if (pn == NULL)
1299                 return -ENOMEM;
1300         pn->fioctl = fcn;
1301         down_write(&snd_ioctl_rwsem);
1302         list_add_tail(&pn->list, lists);
1303         up_write(&snd_ioctl_rwsem);
1304         return 0;
1305 }
1306
1307 int snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn)
1308 {
1309         return _snd_ctl_register_ioctl(fcn, &snd_control_ioctls);
1310 }
1311
1312 EXPORT_SYMBOL(snd_ctl_register_ioctl);
1313
1314 #ifdef CONFIG_COMPAT
1315 int snd_ctl_register_ioctl_compat(snd_kctl_ioctl_func_t fcn)
1316 {
1317         return _snd_ctl_register_ioctl(fcn, &snd_control_compat_ioctls);
1318 }
1319
1320 EXPORT_SYMBOL(snd_ctl_register_ioctl_compat);
1321 #endif
1322
1323 /*
1324  * de-register the device-specific control-ioctls.
1325  */
1326 static int _snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn,
1327                                      struct list_head *lists)
1328 {
1329         struct snd_kctl_ioctl *p;
1330
1331         snd_assert(fcn != NULL, return -EINVAL);
1332         down_write(&snd_ioctl_rwsem);
1333         list_for_each_entry(p, lists, list) {
1334                 if (p->fioctl == fcn) {
1335                         list_del(&p->list);
1336                         up_write(&snd_ioctl_rwsem);
1337                         kfree(p);
1338                         return 0;
1339                 }
1340         }
1341         up_write(&snd_ioctl_rwsem);
1342         snd_BUG();
1343         return -EINVAL;
1344 }
1345
1346 int snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn)
1347 {
1348         return _snd_ctl_unregister_ioctl(fcn, &snd_control_ioctls);
1349 }
1350
1351 EXPORT_SYMBOL(snd_ctl_unregister_ioctl);
1352
1353 #ifdef CONFIG_COMPAT
1354 int snd_ctl_unregister_ioctl_compat(snd_kctl_ioctl_func_t fcn)
1355 {
1356         return _snd_ctl_unregister_ioctl(fcn, &snd_control_compat_ioctls);
1357 }
1358
1359 EXPORT_SYMBOL(snd_ctl_unregister_ioctl_compat);
1360 #endif
1361
1362 static int snd_ctl_fasync(int fd, struct file * file, int on)
1363 {
1364         struct snd_ctl_file *ctl;
1365         int err;
1366         ctl = file->private_data;
1367         err = fasync_helper(fd, file, on, &ctl->fasync);
1368         if (err < 0)
1369                 return err;
1370         return 0;
1371 }
1372
1373 /*
1374  * ioctl32 compat
1375  */
1376 #ifdef CONFIG_COMPAT
1377 #include "control_compat.c"
1378 #else
1379 #define snd_ctl_ioctl_compat    NULL
1380 #endif
1381
1382 /*
1383  *  INIT PART
1384  */
1385
1386 static const struct file_operations snd_ctl_f_ops =
1387 {
1388         .owner =        THIS_MODULE,
1389         .read =         snd_ctl_read,
1390         .open =         snd_ctl_open,
1391         .release =      snd_ctl_release,
1392         .poll =         snd_ctl_poll,
1393         .unlocked_ioctl =       snd_ctl_ioctl,
1394         .compat_ioctl = snd_ctl_ioctl_compat,
1395         .fasync =       snd_ctl_fasync,
1396 };
1397
1398 /*
1399  * registration of the control device
1400  */
1401 static int snd_ctl_dev_register(struct snd_device *device)
1402 {
1403         struct snd_card *card = device->device_data;
1404         int err, cardnum;
1405         char name[16];
1406
1407         snd_assert(card != NULL, return -ENXIO);
1408         cardnum = card->number;
1409         snd_assert(cardnum >= 0 && cardnum < SNDRV_CARDS, return -ENXIO);
1410         sprintf(name, "controlC%i", cardnum);
1411         if ((err = snd_register_device(SNDRV_DEVICE_TYPE_CONTROL, card, -1,
1412                                        &snd_ctl_f_ops, card, name)) < 0)
1413                 return err;
1414         return 0;
1415 }
1416
1417 /*
1418  * disconnection of the control device
1419  */
1420 static int snd_ctl_dev_disconnect(struct snd_device *device)
1421 {
1422         struct snd_card *card = device->device_data;
1423         struct snd_ctl_file *ctl;
1424         int err, cardnum;
1425
1426         snd_assert(card != NULL, return -ENXIO);
1427         cardnum = card->number;
1428         snd_assert(cardnum >= 0 && cardnum < SNDRV_CARDS, return -ENXIO);
1429
1430         down_read(&card->controls_rwsem);
1431         list_for_each_entry(ctl, &card->ctl_files, list) {
1432                 wake_up(&ctl->change_sleep);
1433                 kill_fasync(&ctl->fasync, SIGIO, POLL_ERR);
1434         }
1435         up_read(&card->controls_rwsem);
1436
1437         if ((err = snd_unregister_device(SNDRV_DEVICE_TYPE_CONTROL,
1438                                          card, -1)) < 0)
1439                 return err;
1440         return 0;
1441 }
1442
1443 /*
1444  * free all controls
1445  */
1446 static int snd_ctl_dev_free(struct snd_device *device)
1447 {
1448         struct snd_card *card = device->device_data;
1449         struct snd_kcontrol *control;
1450
1451         down_write(&card->controls_rwsem);
1452         while (!list_empty(&card->controls)) {
1453                 control = snd_kcontrol(card->controls.next);
1454                 snd_ctl_remove(card, control);
1455         }
1456         up_write(&card->controls_rwsem);
1457         return 0;
1458 }
1459
1460 /*
1461  * create control core:
1462  * called from init.c
1463  */
1464 int snd_ctl_create(struct snd_card *card)
1465 {
1466         static struct snd_device_ops ops = {
1467                 .dev_free = snd_ctl_dev_free,
1468                 .dev_register = snd_ctl_dev_register,
1469                 .dev_disconnect = snd_ctl_dev_disconnect,
1470         };
1471
1472         snd_assert(card != NULL, return -ENXIO);
1473         return snd_device_new(card, SNDRV_DEV_CONTROL, card, &ops);
1474 }
1475
1476 /*
1477  * Frequently used control callbacks
1478  */
1479 int snd_ctl_boolean_mono_info(struct snd_kcontrol *kcontrol,
1480                               struct snd_ctl_elem_info *uinfo)
1481 {
1482         uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
1483         uinfo->count = 1;
1484         uinfo->value.integer.min = 0;
1485         uinfo->value.integer.max = 1;
1486         return 0;
1487 }
1488
1489 EXPORT_SYMBOL(snd_ctl_boolean_mono_info);
1490
1491 int snd_ctl_boolean_stereo_info(struct snd_kcontrol *kcontrol,
1492                                 struct snd_ctl_elem_info *uinfo)
1493 {
1494         uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
1495         uinfo->count = 2;
1496         uinfo->value.integer.min = 0;
1497         uinfo->value.integer.max = 1;
1498         return 0;
1499 }
1500
1501 EXPORT_SYMBOL(snd_ctl_boolean_stereo_info);