636b3b52ef8bdd56cc2f7eaccf6a779ca8c9c841
[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 = 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         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         kfree(ctl);
129         module_put(card->module);
130         snd_card_file_remove(card, file);
131         return 0;
132 }
133
134 void snd_ctl_notify(struct snd_card *card, unsigned int mask,
135                     struct snd_ctl_elem_id *id)
136 {
137         unsigned long flags;
138         struct snd_ctl_file *ctl;
139         struct snd_kctl_event *ev;
140         
141         if (snd_BUG_ON(!card || !id))
142                 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         if (snd_BUG_ON(!control || !control->count))
192                 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         if (snd_BUG_ON(!ncontrol || !ncontrol->info))
222                 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                 if (strcmp(ncontrol->name, kctl.id.name) != 0)
230                         snd_printk(KERN_WARNING
231                                    "Control name '%s' truncated to '%s'\n",
232                                    ncontrol->name, kctl.id.name);
233         }
234         kctl.id.index = ncontrol->index;
235         kctl.count = ncontrol->count ? ncontrol->count : 1;
236         access = ncontrol->access == 0 ? SNDRV_CTL_ELEM_ACCESS_READWRITE :
237                  (ncontrol->access & (SNDRV_CTL_ELEM_ACCESS_READWRITE|
238                                       SNDRV_CTL_ELEM_ACCESS_INACTIVE|
239                                       SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE|
240                                       SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK));
241         kctl.info = ncontrol->info;
242         kctl.get = ncontrol->get;
243         kctl.put = ncontrol->put;
244         kctl.tlv.p = ncontrol->tlv.p;
245         kctl.private_value = ncontrol->private_value;
246         kctl.private_data = private_data;
247         return snd_ctl_new(&kctl, access);
248 }
249
250 EXPORT_SYMBOL(snd_ctl_new1);
251
252 /**
253  * snd_ctl_free_one - release the control instance
254  * @kcontrol: the control instance
255  *
256  * Releases the control instance created via snd_ctl_new()
257  * or snd_ctl_new1().
258  * Don't call this after the control was added to the card.
259  */
260 void snd_ctl_free_one(struct snd_kcontrol *kcontrol)
261 {
262         if (kcontrol) {
263                 if (kcontrol->private_free)
264                         kcontrol->private_free(kcontrol);
265                 kfree(kcontrol);
266         }
267 }
268
269 EXPORT_SYMBOL(snd_ctl_free_one);
270
271 static unsigned int snd_ctl_hole_check(struct snd_card *card,
272                                        unsigned int count)
273 {
274         struct snd_kcontrol *kctl;
275
276         list_for_each_entry(kctl, &card->controls, list) {
277                 if ((kctl->id.numid <= card->last_numid &&
278                      kctl->id.numid + kctl->count > card->last_numid) ||
279                     (kctl->id.numid <= card->last_numid + count - 1 &&
280                      kctl->id.numid + kctl->count > card->last_numid + count - 1))
281                         return card->last_numid = kctl->id.numid + kctl->count - 1;
282         }
283         return card->last_numid;
284 }
285
286 static int snd_ctl_find_hole(struct snd_card *card, unsigned int count)
287 {
288         unsigned int last_numid, iter = 100000;
289
290         last_numid = card->last_numid;
291         while (last_numid != snd_ctl_hole_check(card, count)) {
292                 if (--iter == 0) {
293                         /* this situation is very unlikely */
294                         snd_printk(KERN_ERR "unable to allocate new control numid\n");
295                         return -ENOMEM;
296                 }
297                 last_numid = card->last_numid;
298         }
299         return 0;
300 }
301
302 /**
303  * snd_ctl_add - add the control instance to the card
304  * @card: the card instance
305  * @kcontrol: the control instance to add
306  *
307  * Adds the control instance created via snd_ctl_new() or
308  * snd_ctl_new1() to the given card. Assigns also an unique
309  * numid used for fast search.
310  *
311  * Returns zero if successful, or a negative error code on failure.
312  *
313  * It frees automatically the control which cannot be added.
314  */
315 int snd_ctl_add(struct snd_card *card, struct snd_kcontrol *kcontrol)
316 {
317         struct snd_ctl_elem_id id;
318         unsigned int idx;
319         int err = -EINVAL;
320
321         if (! kcontrol)
322                 return err;
323         if (snd_BUG_ON(!card || !kcontrol->info))
324                 goto error;
325         id = kcontrol->id;
326         down_write(&card->controls_rwsem);
327         if (snd_ctl_find_id(card, &id)) {
328                 up_write(&card->controls_rwsem);
329                 snd_printd(KERN_ERR "control %i:%i:%i:%s:%i is already present\n",
330                                         id.iface,
331                                         id.device,
332                                         id.subdevice,
333                                         id.name,
334                                         id.index);
335                 err = -EBUSY;
336                 goto error;
337         }
338         if (snd_ctl_find_hole(card, kcontrol->count) < 0) {
339                 up_write(&card->controls_rwsem);
340                 err = -ENOMEM;
341                 goto error;
342         }
343         list_add_tail(&kcontrol->list, &card->controls);
344         card->controls_count += kcontrol->count;
345         kcontrol->id.numid = card->last_numid + 1;
346         card->last_numid += kcontrol->count;
347         up_write(&card->controls_rwsem);
348         for (idx = 0; idx < kcontrol->count; idx++, id.index++, id.numid++)
349                 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_ADD, &id);
350         return 0;
351
352  error:
353         snd_ctl_free_one(kcontrol);
354         return err;
355 }
356
357 EXPORT_SYMBOL(snd_ctl_add);
358
359 /**
360  * snd_ctl_remove - remove the control from the card and release it
361  * @card: the card instance
362  * @kcontrol: the control instance to remove
363  *
364  * Removes the control from the card and then releases the instance.
365  * You don't need to call snd_ctl_free_one(). You must be in
366  * the write lock - down_write(&card->controls_rwsem).
367  * 
368  * Returns 0 if successful, or a negative error code on failure.
369  */
370 int snd_ctl_remove(struct snd_card *card, struct snd_kcontrol *kcontrol)
371 {
372         struct snd_ctl_elem_id id;
373         unsigned int idx;
374
375         if (snd_BUG_ON(!card || !kcontrol))
376                 return -EINVAL;
377         list_del(&kcontrol->list);
378         card->controls_count -= kcontrol->count;
379         id = kcontrol->id;
380         for (idx = 0; idx < kcontrol->count; idx++, id.index++, id.numid++)
381                 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_REMOVE, &id);
382         snd_ctl_free_one(kcontrol);
383         return 0;
384 }
385
386 EXPORT_SYMBOL(snd_ctl_remove);
387
388 /**
389  * snd_ctl_remove_id - remove the control of the given id and release it
390  * @card: the card instance
391  * @id: the control id to remove
392  *
393  * Finds the control instance with the given id, removes it from the
394  * card list and releases it.
395  * 
396  * Returns 0 if successful, or a negative error code on failure.
397  */
398 int snd_ctl_remove_id(struct snd_card *card, struct snd_ctl_elem_id *id)
399 {
400         struct snd_kcontrol *kctl;
401         int ret;
402
403         down_write(&card->controls_rwsem);
404         kctl = snd_ctl_find_id(card, id);
405         if (kctl == NULL) {
406                 up_write(&card->controls_rwsem);
407                 return -ENOENT;
408         }
409         ret = snd_ctl_remove(card, kctl);
410         up_write(&card->controls_rwsem);
411         return ret;
412 }
413
414 EXPORT_SYMBOL(snd_ctl_remove_id);
415
416 /**
417  * snd_ctl_remove_unlocked_id - remove the unlocked control of the given id and release it
418  * @file: active control handle
419  * @id: the control id to remove
420  *
421  * Finds the control instance with the given id, removes it from the
422  * card list and releases it.
423  * 
424  * Returns 0 if successful, or a negative error code on failure.
425  */
426 static int snd_ctl_remove_unlocked_id(struct snd_ctl_file * file,
427                                       struct snd_ctl_elem_id *id)
428 {
429         struct snd_card *card = file->card;
430         struct snd_kcontrol *kctl;
431         int idx, ret;
432
433         down_write(&card->controls_rwsem);
434         kctl = snd_ctl_find_id(card, id);
435         if (kctl == NULL) {
436                 up_write(&card->controls_rwsem);
437                 return -ENOENT;
438         }
439         for (idx = 0; idx < kctl->count; idx++)
440                 if (kctl->vd[idx].owner != NULL && kctl->vd[idx].owner != file) {
441                         up_write(&card->controls_rwsem);
442                         return -EBUSY;
443                 }
444         ret = snd_ctl_remove(card, kctl);
445         up_write(&card->controls_rwsem);
446         return ret;
447 }
448
449 /**
450  * snd_ctl_rename_id - replace the id of a control on the card
451  * @card: the card instance
452  * @src_id: the old id
453  * @dst_id: the new id
454  *
455  * Finds the control with the old id from the card, and replaces the
456  * id with the new one.
457  *
458  * Returns zero if successful, or a negative error code on failure.
459  */
460 int snd_ctl_rename_id(struct snd_card *card, struct snd_ctl_elem_id *src_id,
461                       struct snd_ctl_elem_id *dst_id)
462 {
463         struct snd_kcontrol *kctl;
464
465         down_write(&card->controls_rwsem);
466         kctl = snd_ctl_find_id(card, src_id);
467         if (kctl == NULL) {
468                 up_write(&card->controls_rwsem);
469                 return -ENOENT;
470         }
471         kctl->id = *dst_id;
472         kctl->id.numid = card->last_numid + 1;
473         card->last_numid += kctl->count;
474         up_write(&card->controls_rwsem);
475         return 0;
476 }
477
478 EXPORT_SYMBOL(snd_ctl_rename_id);
479
480 /**
481  * snd_ctl_find_numid - find the control instance with the given number-id
482  * @card: the card instance
483  * @numid: the number-id to search
484  *
485  * Finds the control instance with the given number-id from the card.
486  *
487  * Returns the pointer of the instance if found, or NULL if not.
488  *
489  * The caller must down card->controls_rwsem before calling this function
490  * (if the race condition can happen).
491  */
492 struct snd_kcontrol *snd_ctl_find_numid(struct snd_card *card, unsigned int numid)
493 {
494         struct snd_kcontrol *kctl;
495
496         if (snd_BUG_ON(!card || !numid))
497                 return NULL;
498         list_for_each_entry(kctl, &card->controls, list) {
499                 if (kctl->id.numid <= numid && kctl->id.numid + kctl->count > numid)
500                         return kctl;
501         }
502         return NULL;
503 }
504
505 EXPORT_SYMBOL(snd_ctl_find_numid);
506
507 /**
508  * snd_ctl_find_id - find the control instance with the given id
509  * @card: the card instance
510  * @id: the id to search
511  *
512  * Finds the control instance with the given id from the card.
513  *
514  * Returns the pointer of the instance if found, or NULL if not.
515  *
516  * The caller must down card->controls_rwsem before calling this function
517  * (if the race condition can happen).
518  */
519 struct snd_kcontrol *snd_ctl_find_id(struct snd_card *card,
520                                      struct snd_ctl_elem_id *id)
521 {
522         struct snd_kcontrol *kctl;
523
524         if (snd_BUG_ON(!card || !id))
525                 return NULL;
526         if (id->numid != 0)
527                 return snd_ctl_find_numid(card, id->numid);
528         list_for_each_entry(kctl, &card->controls, list) {
529                 if (kctl->id.iface != id->iface)
530                         continue;
531                 if (kctl->id.device != id->device)
532                         continue;
533                 if (kctl->id.subdevice != id->subdevice)
534                         continue;
535                 if (strncmp(kctl->id.name, id->name, sizeof(kctl->id.name)))
536                         continue;
537                 if (kctl->id.index > id->index)
538                         continue;
539                 if (kctl->id.index + kctl->count <= id->index)
540                         continue;
541                 return kctl;
542         }
543         return NULL;
544 }
545
546 EXPORT_SYMBOL(snd_ctl_find_id);
547
548 static int snd_ctl_card_info(struct snd_card *card, struct snd_ctl_file * ctl,
549                              unsigned int cmd, void __user *arg)
550 {
551         struct snd_ctl_card_info *info;
552
553         info = kzalloc(sizeof(*info), GFP_KERNEL);
554         if (! info)
555                 return -ENOMEM;
556         down_read(&snd_ioctl_rwsem);
557         info->card = card->number;
558         strlcpy(info->id, card->id, sizeof(info->id));
559         strlcpy(info->driver, card->driver, sizeof(info->driver));
560         strlcpy(info->name, card->shortname, sizeof(info->name));
561         strlcpy(info->longname, card->longname, sizeof(info->longname));
562         strlcpy(info->mixername, card->mixername, sizeof(info->mixername));
563         strlcpy(info->components, card->components, sizeof(info->components));
564         up_read(&snd_ioctl_rwsem);
565         if (copy_to_user(arg, info, sizeof(struct snd_ctl_card_info))) {
566                 kfree(info);
567                 return -EFAULT;
568         }
569         kfree(info);
570         return 0;
571 }
572
573 static int snd_ctl_elem_list(struct snd_card *card,
574                              struct snd_ctl_elem_list __user *_list)
575 {
576         struct list_head *plist;
577         struct snd_ctl_elem_list list;
578         struct snd_kcontrol *kctl;
579         struct snd_ctl_elem_id *dst, *id;
580         unsigned int offset, space, first, jidx;
581         
582         if (copy_from_user(&list, _list, sizeof(list)))
583                 return -EFAULT;
584         offset = list.offset;
585         space = list.space;
586         first = 0;
587         /* try limit maximum space */
588         if (space > 16384)
589                 return -ENOMEM;
590         if (space > 0) {
591                 /* allocate temporary buffer for atomic operation */
592                 dst = vmalloc(space * sizeof(struct snd_ctl_elem_id));
593                 if (dst == NULL)
594                         return -ENOMEM;
595                 down_read(&card->controls_rwsem);
596                 list.count = card->controls_count;
597                 plist = card->controls.next;
598                 while (plist != &card->controls) {
599                         if (offset == 0)
600                                 break;
601                         kctl = snd_kcontrol(plist);
602                         if (offset < kctl->count)
603                                 break;
604                         offset -= kctl->count;
605                         plist = plist->next;
606                 }
607                 list.used = 0;
608                 id = dst;
609                 while (space > 0 && plist != &card->controls) {
610                         kctl = snd_kcontrol(plist);
611                         for (jidx = offset; space > 0 && jidx < kctl->count; jidx++) {
612                                 snd_ctl_build_ioff(id, kctl, jidx);
613                                 id++;
614                                 space--;
615                                 list.used++;
616                         }
617                         plist = plist->next;
618                         offset = 0;
619                 }
620                 up_read(&card->controls_rwsem);
621                 if (list.used > 0 &&
622                     copy_to_user(list.pids, dst,
623                                  list.used * sizeof(struct snd_ctl_elem_id))) {
624                         vfree(dst);
625                         return -EFAULT;
626                 }
627                 vfree(dst);
628         } else {
629                 down_read(&card->controls_rwsem);
630                 list.count = card->controls_count;
631                 up_read(&card->controls_rwsem);
632         }
633         if (copy_to_user(_list, &list, sizeof(list)))
634                 return -EFAULT;
635         return 0;
636 }
637
638 static int snd_ctl_elem_info(struct snd_ctl_file *ctl,
639                              struct snd_ctl_elem_info *info)
640 {
641         struct snd_card *card = ctl->card;
642         struct snd_kcontrol *kctl;
643         struct snd_kcontrol_volatile *vd;
644         unsigned int index_offset;
645         int result;
646         
647         down_read(&card->controls_rwsem);
648         kctl = snd_ctl_find_id(card, &info->id);
649         if (kctl == NULL) {
650                 up_read(&card->controls_rwsem);
651                 return -ENOENT;
652         }
653 #ifdef CONFIG_SND_DEBUG
654         info->access = 0;
655 #endif
656         result = kctl->info(kctl, info);
657         if (result >= 0) {
658                 snd_BUG_ON(info->access);
659                 index_offset = snd_ctl_get_ioff(kctl, &info->id);
660                 vd = &kctl->vd[index_offset];
661                 snd_ctl_build_ioff(&info->id, kctl, index_offset);
662                 info->access = vd->access;
663                 if (vd->owner) {
664                         info->access |= SNDRV_CTL_ELEM_ACCESS_LOCK;
665                         if (vd->owner == ctl)
666                                 info->access |= SNDRV_CTL_ELEM_ACCESS_OWNER;
667                         info->owner = vd->owner_pid;
668                 } else {
669                         info->owner = -1;
670                 }
671         }
672         up_read(&card->controls_rwsem);
673         return result;
674 }
675
676 static int snd_ctl_elem_info_user(struct snd_ctl_file *ctl,
677                                   struct snd_ctl_elem_info __user *_info)
678 {
679         struct snd_ctl_elem_info info;
680         int result;
681
682         if (copy_from_user(&info, _info, sizeof(info)))
683                 return -EFAULT;
684         snd_power_lock(ctl->card);
685         result = snd_power_wait(ctl->card, SNDRV_CTL_POWER_D0);
686         if (result >= 0)
687                 result = snd_ctl_elem_info(ctl, &info);
688         snd_power_unlock(ctl->card);
689         if (result >= 0)
690                 if (copy_to_user(_info, &info, sizeof(info)))
691                         return -EFAULT;
692         return result;
693 }
694
695 static int snd_ctl_elem_read(struct snd_card *card,
696                              struct snd_ctl_elem_value *control)
697 {
698         struct snd_kcontrol *kctl;
699         struct snd_kcontrol_volatile *vd;
700         unsigned int index_offset;
701         int result;
702
703         down_read(&card->controls_rwsem);
704         kctl = snd_ctl_find_id(card, &control->id);
705         if (kctl == NULL) {
706                 result = -ENOENT;
707         } else {
708                 index_offset = snd_ctl_get_ioff(kctl, &control->id);
709                 vd = &kctl->vd[index_offset];
710                 if ((vd->access & SNDRV_CTL_ELEM_ACCESS_READ) &&
711                     kctl->get != NULL) {
712                         snd_ctl_build_ioff(&control->id, kctl, index_offset);
713                         result = kctl->get(kctl, control);
714                 } else
715                         result = -EPERM;
716         }
717         up_read(&card->controls_rwsem);
718         return result;
719 }
720
721 static int snd_ctl_elem_read_user(struct snd_card *card,
722                                   struct snd_ctl_elem_value __user *_control)
723 {
724         struct snd_ctl_elem_value *control;
725         int result;
726         
727         control = kmalloc(sizeof(*control), GFP_KERNEL);
728         if (control == NULL)
729                 return -ENOMEM; 
730         if (copy_from_user(control, _control, sizeof(*control))) {
731                 kfree(control);
732                 return -EFAULT;
733         }
734         snd_power_lock(card);
735         result = snd_power_wait(card, SNDRV_CTL_POWER_D0);
736         if (result >= 0)
737                 result = snd_ctl_elem_read(card, control);
738         snd_power_unlock(card);
739         if (result >= 0)
740                 if (copy_to_user(_control, control, sizeof(*control)))
741                         result = -EFAULT;
742         kfree(control);
743         return result;
744 }
745
746 static int snd_ctl_elem_write(struct snd_card *card, struct snd_ctl_file *file,
747                               struct snd_ctl_elem_value *control)
748 {
749         struct snd_kcontrol *kctl;
750         struct snd_kcontrol_volatile *vd;
751         unsigned int index_offset;
752         int result;
753
754         down_read(&card->controls_rwsem);
755         kctl = snd_ctl_find_id(card, &control->id);
756         if (kctl == NULL) {
757                 result = -ENOENT;
758         } else {
759                 index_offset = snd_ctl_get_ioff(kctl, &control->id);
760                 vd = &kctl->vd[index_offset];
761                 if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_WRITE) ||
762                     kctl->put == NULL ||
763                     (file && vd->owner && vd->owner != file)) {
764                         result = -EPERM;
765                 } else {
766                         snd_ctl_build_ioff(&control->id, kctl, index_offset);
767                         result = kctl->put(kctl, control);
768                 }
769                 if (result > 0) {
770                         up_read(&card->controls_rwsem);
771                         snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
772                                        &control->id);
773                         return 0;
774                 }
775         }
776         up_read(&card->controls_rwsem);
777         return result;
778 }
779
780 static int snd_ctl_elem_write_user(struct snd_ctl_file *file,
781                                    struct snd_ctl_elem_value __user *_control)
782 {
783         struct snd_ctl_elem_value *control;
784         struct snd_card *card;
785         int result;
786
787         control = kmalloc(sizeof(*control), GFP_KERNEL);
788         if (control == NULL)
789                 return -ENOMEM; 
790         if (copy_from_user(control, _control, sizeof(*control))) {
791                 kfree(control);
792                 return -EFAULT;
793         }
794         card = file->card;
795         snd_power_lock(card);
796         result = snd_power_wait(card, SNDRV_CTL_POWER_D0);
797         if (result >= 0)
798                 result = snd_ctl_elem_write(card, file, control);
799         snd_power_unlock(card);
800         if (result >= 0)
801                 if (copy_to_user(_control, control, sizeof(*control)))
802                         result = -EFAULT;
803         kfree(control);
804         return result;
805 }
806
807 static int snd_ctl_elem_lock(struct snd_ctl_file *file,
808                              struct snd_ctl_elem_id __user *_id)
809 {
810         struct snd_card *card = file->card;
811         struct snd_ctl_elem_id id;
812         struct snd_kcontrol *kctl;
813         struct snd_kcontrol_volatile *vd;
814         int result;
815         
816         if (copy_from_user(&id, _id, sizeof(id)))
817                 return -EFAULT;
818         down_write(&card->controls_rwsem);
819         kctl = snd_ctl_find_id(card, &id);
820         if (kctl == NULL) {
821                 result = -ENOENT;
822         } else {
823                 vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)];
824                 if (vd->owner != NULL)
825                         result = -EBUSY;
826                 else {
827                         vd->owner = file;
828                         vd->owner_pid = current->pid;
829                         result = 0;
830                 }
831         }
832         up_write(&card->controls_rwsem);
833         return result;
834 }
835
836 static int snd_ctl_elem_unlock(struct snd_ctl_file *file,
837                                struct snd_ctl_elem_id __user *_id)
838 {
839         struct snd_card *card = file->card;
840         struct snd_ctl_elem_id id;
841         struct snd_kcontrol *kctl;
842         struct snd_kcontrol_volatile *vd;
843         int result;
844         
845         if (copy_from_user(&id, _id, sizeof(id)))
846                 return -EFAULT;
847         down_write(&card->controls_rwsem);
848         kctl = snd_ctl_find_id(card, &id);
849         if (kctl == NULL) {
850                 result = -ENOENT;
851         } else {
852                 vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)];
853                 if (vd->owner == NULL)
854                         result = -EINVAL;
855                 else if (vd->owner != file)
856                         result = -EPERM;
857                 else {
858                         vd->owner = NULL;
859                         vd->owner_pid = 0;
860                         result = 0;
861                 }
862         }
863         up_write(&card->controls_rwsem);
864         return result;
865 }
866
867 struct user_element {
868         struct snd_ctl_elem_info info;
869         void *elem_data;                /* element data */
870         unsigned long elem_data_size;   /* size of element data in bytes */
871         void *tlv_data;                 /* TLV data */
872         unsigned long tlv_data_size;    /* TLV data size */
873         void *priv_data;                /* private data (like strings for enumerated type) */
874         unsigned long priv_data_size;   /* size of private data in bytes */
875 };
876
877 static int snd_ctl_elem_user_info(struct snd_kcontrol *kcontrol,
878                                   struct snd_ctl_elem_info *uinfo)
879 {
880         struct user_element *ue = kcontrol->private_data;
881
882         *uinfo = ue->info;
883         return 0;
884 }
885
886 static int snd_ctl_elem_user_get(struct snd_kcontrol *kcontrol,
887                                  struct snd_ctl_elem_value *ucontrol)
888 {
889         struct user_element *ue = kcontrol->private_data;
890
891         memcpy(&ucontrol->value, ue->elem_data, ue->elem_data_size);
892         return 0;
893 }
894
895 static int snd_ctl_elem_user_put(struct snd_kcontrol *kcontrol,
896                                  struct snd_ctl_elem_value *ucontrol)
897 {
898         int change;
899         struct user_element *ue = kcontrol->private_data;
900         
901         change = memcmp(&ucontrol->value, ue->elem_data, ue->elem_data_size) != 0;
902         if (change)
903                 memcpy(ue->elem_data, &ucontrol->value, ue->elem_data_size);
904         return change;
905 }
906
907 static int snd_ctl_elem_user_tlv(struct snd_kcontrol *kcontrol,
908                                  int op_flag,
909                                  unsigned int size,
910                                  unsigned int __user *tlv)
911 {
912         struct user_element *ue = kcontrol->private_data;
913         int change = 0;
914         void *new_data;
915
916         if (op_flag > 0) {
917                 if (size > 1024 * 128)  /* sane value */
918                         return -EINVAL;
919                 new_data = kmalloc(size, GFP_KERNEL);
920                 if (new_data == NULL)
921                         return -ENOMEM;
922                 if (copy_from_user(new_data, tlv, size)) {
923                         kfree(new_data);
924                         return -EFAULT;
925                 }
926                 change = ue->tlv_data_size != size;
927                 if (!change)
928                         change = memcmp(ue->tlv_data, new_data, size);
929                 kfree(ue->tlv_data);
930                 ue->tlv_data = new_data;
931                 ue->tlv_data_size = size;
932         } else {
933                 if (! ue->tlv_data_size || ! ue->tlv_data)
934                         return -ENXIO;
935                 if (size < ue->tlv_data_size)
936                         return -ENOSPC;
937                 if (copy_to_user(tlv, ue->tlv_data, ue->tlv_data_size))
938                         return -EFAULT;
939         }
940         return change;
941 }
942
943 static void snd_ctl_elem_user_free(struct snd_kcontrol *kcontrol)
944 {
945         struct user_element *ue = kcontrol->private_data;
946         if (ue->tlv_data)
947                 kfree(ue->tlv_data);
948         kfree(ue);
949 }
950
951 static int snd_ctl_elem_add(struct snd_ctl_file *file,
952                             struct snd_ctl_elem_info *info, int replace)
953 {
954         struct snd_card *card = file->card;
955         struct snd_kcontrol kctl, *_kctl;
956         unsigned int access;
957         long private_size;
958         struct user_element *ue;
959         int idx, err;
960         
961         if (card->user_ctl_count >= MAX_USER_CONTROLS)
962                 return -ENOMEM;
963         if (info->count > 1024)
964                 return -EINVAL;
965         access = info->access == 0 ? SNDRV_CTL_ELEM_ACCESS_READWRITE :
966                 (info->access & (SNDRV_CTL_ELEM_ACCESS_READWRITE|
967                                  SNDRV_CTL_ELEM_ACCESS_INACTIVE|
968                                  SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE));
969         info->id.numid = 0;
970         memset(&kctl, 0, sizeof(kctl));
971         down_write(&card->controls_rwsem);
972         _kctl = snd_ctl_find_id(card, &info->id);
973         err = 0;
974         if (_kctl) {
975                 if (replace)
976                         err = snd_ctl_remove(card, _kctl);
977                 else
978                         err = -EBUSY;
979         } else {
980                 if (replace)
981                         err = -ENOENT;
982         }
983         up_write(&card->controls_rwsem);
984         if (err < 0)
985                 return err;
986         memcpy(&kctl.id, &info->id, sizeof(info->id));
987         kctl.count = info->owner ? info->owner : 1;
988         access |= SNDRV_CTL_ELEM_ACCESS_USER;
989         kctl.info = snd_ctl_elem_user_info;
990         if (access & SNDRV_CTL_ELEM_ACCESS_READ)
991                 kctl.get = snd_ctl_elem_user_get;
992         if (access & SNDRV_CTL_ELEM_ACCESS_WRITE)
993                 kctl.put = snd_ctl_elem_user_put;
994         if (access & SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE) {
995                 kctl.tlv.c = snd_ctl_elem_user_tlv;
996                 access |= SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
997         }
998         switch (info->type) {
999         case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
1000         case SNDRV_CTL_ELEM_TYPE_INTEGER:
1001                 private_size = sizeof(long);
1002                 if (info->count > 128)
1003                         return -EINVAL;
1004                 break;
1005         case SNDRV_CTL_ELEM_TYPE_INTEGER64:
1006                 private_size = sizeof(long long);
1007                 if (info->count > 64)
1008                         return -EINVAL;
1009                 break;
1010         case SNDRV_CTL_ELEM_TYPE_BYTES:
1011                 private_size = sizeof(unsigned char);
1012                 if (info->count > 512)
1013                         return -EINVAL;
1014                 break;
1015         case SNDRV_CTL_ELEM_TYPE_IEC958:
1016                 private_size = sizeof(struct snd_aes_iec958);
1017                 if (info->count != 1)
1018                         return -EINVAL;
1019                 break;
1020         default:
1021                 return -EINVAL;
1022         }
1023         private_size *= info->count;
1024         ue = kzalloc(sizeof(struct user_element) + private_size, GFP_KERNEL);
1025         if (ue == NULL)
1026                 return -ENOMEM;
1027         ue->info = *info;
1028         ue->info.access = 0;
1029         ue->elem_data = (char *)ue + sizeof(*ue);
1030         ue->elem_data_size = private_size;
1031         kctl.private_free = snd_ctl_elem_user_free;
1032         _kctl = snd_ctl_new(&kctl, access);
1033         if (_kctl == NULL) {
1034                 kfree(ue);
1035                 return -ENOMEM;
1036         }
1037         _kctl->private_data = ue;
1038         for (idx = 0; idx < _kctl->count; idx++)
1039                 _kctl->vd[idx].owner = file;
1040         err = snd_ctl_add(card, _kctl);
1041         if (err < 0)
1042                 return err;
1043
1044         down_write(&card->controls_rwsem);
1045         card->user_ctl_count++;
1046         up_write(&card->controls_rwsem);
1047
1048         return 0;
1049 }
1050
1051 static int snd_ctl_elem_add_user(struct snd_ctl_file *file,
1052                                  struct snd_ctl_elem_info __user *_info, int replace)
1053 {
1054         struct snd_ctl_elem_info info;
1055         if (copy_from_user(&info, _info, sizeof(info)))
1056                 return -EFAULT;
1057         return snd_ctl_elem_add(file, &info, replace);
1058 }
1059
1060 static int snd_ctl_elem_remove(struct snd_ctl_file *file,
1061                                struct snd_ctl_elem_id __user *_id)
1062 {
1063         struct snd_ctl_elem_id id;
1064         int err;
1065
1066         if (copy_from_user(&id, _id, sizeof(id)))
1067                 return -EFAULT;
1068         err = snd_ctl_remove_unlocked_id(file, &id);
1069         if (! err) {
1070                 struct snd_card *card = file->card;
1071                 down_write(&card->controls_rwsem);
1072                 card->user_ctl_count--;
1073                 up_write(&card->controls_rwsem);
1074         }
1075         return err;
1076 }
1077
1078 static int snd_ctl_subscribe_events(struct snd_ctl_file *file, int __user *ptr)
1079 {
1080         int subscribe;
1081         if (get_user(subscribe, ptr))
1082                 return -EFAULT;
1083         if (subscribe < 0) {
1084                 subscribe = file->subscribed;
1085                 if (put_user(subscribe, ptr))
1086                         return -EFAULT;
1087                 return 0;
1088         }
1089         if (subscribe) {
1090                 file->subscribed = 1;
1091                 return 0;
1092         } else if (file->subscribed) {
1093                 snd_ctl_empty_read_queue(file);
1094                 file->subscribed = 0;
1095         }
1096         return 0;
1097 }
1098
1099 static int snd_ctl_tlv_ioctl(struct snd_ctl_file *file,
1100                              struct snd_ctl_tlv __user *_tlv,
1101                              int op_flag)
1102 {
1103         struct snd_card *card = file->card;
1104         struct snd_ctl_tlv tlv;
1105         struct snd_kcontrol *kctl;
1106         struct snd_kcontrol_volatile *vd;
1107         unsigned int len;
1108         int err = 0;
1109
1110         if (copy_from_user(&tlv, _tlv, sizeof(tlv)))
1111                 return -EFAULT;
1112         if (tlv.length < sizeof(unsigned int) * 3)
1113                 return -EINVAL;
1114         down_read(&card->controls_rwsem);
1115         kctl = snd_ctl_find_numid(card, tlv.numid);
1116         if (kctl == NULL) {
1117                 err = -ENOENT;
1118                 goto __kctl_end;
1119         }
1120         if (kctl->tlv.p == NULL) {
1121                 err = -ENXIO;
1122                 goto __kctl_end;
1123         }
1124         vd = &kctl->vd[tlv.numid - kctl->id.numid];
1125         if ((op_flag == 0 && (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_READ) == 0) ||
1126             (op_flag > 0 && (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_WRITE) == 0) ||
1127             (op_flag < 0 && (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND) == 0)) {
1128                 err = -ENXIO;
1129                 goto __kctl_end;
1130         }
1131         if (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK) {
1132                 if (file && vd->owner != NULL && vd->owner != file) {
1133                         err = -EPERM;
1134                         goto __kctl_end;
1135                 }
1136                 err = kctl->tlv.c(kctl, op_flag, tlv.length, _tlv->tlv); 
1137                 if (err > 0) {
1138                         up_read(&card->controls_rwsem);
1139                         snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_TLV, &kctl->id);
1140                         return 0;
1141                 }
1142         } else {
1143                 if (op_flag) {
1144                         err = -ENXIO;
1145                         goto __kctl_end;
1146                 }
1147                 len = kctl->tlv.p[1] + 2 * sizeof(unsigned int);
1148                 if (tlv.length < len) {
1149                         err = -ENOMEM;
1150                         goto __kctl_end;
1151                 }
1152                 if (copy_to_user(_tlv->tlv, kctl->tlv.p, len))
1153                         err = -EFAULT;
1154         }
1155       __kctl_end:
1156         up_read(&card->controls_rwsem);
1157         return err;
1158 }
1159
1160 static long snd_ctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1161 {
1162         struct snd_ctl_file *ctl;
1163         struct snd_card *card;
1164         struct snd_kctl_ioctl *p;
1165         void __user *argp = (void __user *)arg;
1166         int __user *ip = argp;
1167         int err;
1168
1169         ctl = file->private_data;
1170         card = ctl->card;
1171         if (snd_BUG_ON(!card))
1172                 return -ENXIO;
1173         switch (cmd) {
1174         case SNDRV_CTL_IOCTL_PVERSION:
1175                 return put_user(SNDRV_CTL_VERSION, ip) ? -EFAULT : 0;
1176         case SNDRV_CTL_IOCTL_CARD_INFO:
1177                 return snd_ctl_card_info(card, ctl, cmd, argp);
1178         case SNDRV_CTL_IOCTL_ELEM_LIST:
1179                 return snd_ctl_elem_list(card, argp);
1180         case SNDRV_CTL_IOCTL_ELEM_INFO:
1181                 return snd_ctl_elem_info_user(ctl, argp);
1182         case SNDRV_CTL_IOCTL_ELEM_READ:
1183                 return snd_ctl_elem_read_user(card, argp);
1184         case SNDRV_CTL_IOCTL_ELEM_WRITE:
1185                 return snd_ctl_elem_write_user(ctl, argp);
1186         case SNDRV_CTL_IOCTL_ELEM_LOCK:
1187                 return snd_ctl_elem_lock(ctl, argp);
1188         case SNDRV_CTL_IOCTL_ELEM_UNLOCK:
1189                 return snd_ctl_elem_unlock(ctl, argp);
1190         case SNDRV_CTL_IOCTL_ELEM_ADD:
1191                 return snd_ctl_elem_add_user(ctl, argp, 0);
1192         case SNDRV_CTL_IOCTL_ELEM_REPLACE:
1193                 return snd_ctl_elem_add_user(ctl, argp, 1);
1194         case SNDRV_CTL_IOCTL_ELEM_REMOVE:
1195                 return snd_ctl_elem_remove(ctl, argp);
1196         case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS:
1197                 return snd_ctl_subscribe_events(ctl, ip);
1198         case SNDRV_CTL_IOCTL_TLV_READ:
1199                 return snd_ctl_tlv_ioctl(ctl, argp, 0);
1200         case SNDRV_CTL_IOCTL_TLV_WRITE:
1201                 return snd_ctl_tlv_ioctl(ctl, argp, 1);
1202         case SNDRV_CTL_IOCTL_TLV_COMMAND:
1203                 return snd_ctl_tlv_ioctl(ctl, argp, -1);
1204         case SNDRV_CTL_IOCTL_POWER:
1205                 return -ENOPROTOOPT;
1206         case SNDRV_CTL_IOCTL_POWER_STATE:
1207 #ifdef CONFIG_PM
1208                 return put_user(card->power_state, ip) ? -EFAULT : 0;
1209 #else
1210                 return put_user(SNDRV_CTL_POWER_D0, ip) ? -EFAULT : 0;
1211 #endif
1212         }
1213         down_read(&snd_ioctl_rwsem);
1214         list_for_each_entry(p, &snd_control_ioctls, list) {
1215                 err = p->fioctl(card, ctl, cmd, arg);
1216                 if (err != -ENOIOCTLCMD) {
1217                         up_read(&snd_ioctl_rwsem);
1218                         return err;
1219                 }
1220         }
1221         up_read(&snd_ioctl_rwsem);
1222         snd_printdd("unknown ioctl = 0x%x\n", cmd);
1223         return -ENOTTY;
1224 }
1225
1226 static ssize_t snd_ctl_read(struct file *file, char __user *buffer,
1227                             size_t count, loff_t * offset)
1228 {
1229         struct snd_ctl_file *ctl;
1230         int err = 0;
1231         ssize_t result = 0;
1232
1233         ctl = file->private_data;
1234         if (snd_BUG_ON(!ctl || !ctl->card))
1235                 return -ENXIO;
1236         if (!ctl->subscribed)
1237                 return -EBADFD;
1238         if (count < sizeof(struct snd_ctl_event))
1239                 return -EINVAL;
1240         spin_lock_irq(&ctl->read_lock);
1241         while (count >= sizeof(struct snd_ctl_event)) {
1242                 struct snd_ctl_event ev;
1243                 struct snd_kctl_event *kev;
1244                 while (list_empty(&ctl->events)) {
1245                         wait_queue_t wait;
1246                         if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) {
1247                                 err = -EAGAIN;
1248                                 goto __end_lock;
1249                         }
1250                         init_waitqueue_entry(&wait, current);
1251                         add_wait_queue(&ctl->change_sleep, &wait);
1252                         set_current_state(TASK_INTERRUPTIBLE);
1253                         spin_unlock_irq(&ctl->read_lock);
1254                         schedule();
1255                         remove_wait_queue(&ctl->change_sleep, &wait);
1256                         if (signal_pending(current))
1257                                 return -ERESTARTSYS;
1258                         spin_lock_irq(&ctl->read_lock);
1259                 }
1260                 kev = snd_kctl_event(ctl->events.next);
1261                 ev.type = SNDRV_CTL_EVENT_ELEM;
1262                 ev.data.elem.mask = kev->mask;
1263                 ev.data.elem.id = kev->id;
1264                 list_del(&kev->list);
1265                 spin_unlock_irq(&ctl->read_lock);
1266                 kfree(kev);
1267                 if (copy_to_user(buffer, &ev, sizeof(struct snd_ctl_event))) {
1268                         err = -EFAULT;
1269                         goto __end;
1270                 }
1271                 spin_lock_irq(&ctl->read_lock);
1272                 buffer += sizeof(struct snd_ctl_event);
1273                 count -= sizeof(struct snd_ctl_event);
1274                 result += sizeof(struct snd_ctl_event);
1275         }
1276       __end_lock:
1277         spin_unlock_irq(&ctl->read_lock);
1278       __end:
1279         return result > 0 ? result : err;
1280 }
1281
1282 static unsigned int snd_ctl_poll(struct file *file, poll_table * wait)
1283 {
1284         unsigned int mask;
1285         struct snd_ctl_file *ctl;
1286
1287         ctl = file->private_data;
1288         if (!ctl->subscribed)
1289                 return 0;
1290         poll_wait(file, &ctl->change_sleep, wait);
1291
1292         mask = 0;
1293         if (!list_empty(&ctl->events))
1294                 mask |= POLLIN | POLLRDNORM;
1295
1296         return mask;
1297 }
1298
1299 /*
1300  * register the device-specific control-ioctls.
1301  * called from each device manager like pcm.c, hwdep.c, etc.
1302  */
1303 static int _snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn, struct list_head *lists)
1304 {
1305         struct snd_kctl_ioctl *pn;
1306
1307         pn = kzalloc(sizeof(struct snd_kctl_ioctl), GFP_KERNEL);
1308         if (pn == NULL)
1309                 return -ENOMEM;
1310         pn->fioctl = fcn;
1311         down_write(&snd_ioctl_rwsem);
1312         list_add_tail(&pn->list, lists);
1313         up_write(&snd_ioctl_rwsem);
1314         return 0;
1315 }
1316
1317 int snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn)
1318 {
1319         return _snd_ctl_register_ioctl(fcn, &snd_control_ioctls);
1320 }
1321
1322 EXPORT_SYMBOL(snd_ctl_register_ioctl);
1323
1324 #ifdef CONFIG_COMPAT
1325 int snd_ctl_register_ioctl_compat(snd_kctl_ioctl_func_t fcn)
1326 {
1327         return _snd_ctl_register_ioctl(fcn, &snd_control_compat_ioctls);
1328 }
1329
1330 EXPORT_SYMBOL(snd_ctl_register_ioctl_compat);
1331 #endif
1332
1333 /*
1334  * de-register the device-specific control-ioctls.
1335  */
1336 static int _snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn,
1337                                      struct list_head *lists)
1338 {
1339         struct snd_kctl_ioctl *p;
1340
1341         if (snd_BUG_ON(!fcn))
1342                 return -EINVAL;
1343         down_write(&snd_ioctl_rwsem);
1344         list_for_each_entry(p, lists, list) {
1345                 if (p->fioctl == fcn) {
1346                         list_del(&p->list);
1347                         up_write(&snd_ioctl_rwsem);
1348                         kfree(p);
1349                         return 0;
1350                 }
1351         }
1352         up_write(&snd_ioctl_rwsem);
1353         snd_BUG();
1354         return -EINVAL;
1355 }
1356
1357 int snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn)
1358 {
1359         return _snd_ctl_unregister_ioctl(fcn, &snd_control_ioctls);
1360 }
1361
1362 EXPORT_SYMBOL(snd_ctl_unregister_ioctl);
1363
1364 #ifdef CONFIG_COMPAT
1365 int snd_ctl_unregister_ioctl_compat(snd_kctl_ioctl_func_t fcn)
1366 {
1367         return _snd_ctl_unregister_ioctl(fcn, &snd_control_compat_ioctls);
1368 }
1369
1370 EXPORT_SYMBOL(snd_ctl_unregister_ioctl_compat);
1371 #endif
1372
1373 static int snd_ctl_fasync(int fd, struct file * file, int on)
1374 {
1375         struct snd_ctl_file *ctl;
1376         int err;
1377         ctl = file->private_data;
1378         err = fasync_helper(fd, file, on, &ctl->fasync);
1379         if (err < 0)
1380                 return err;
1381         return 0;
1382 }
1383
1384 /*
1385  * ioctl32 compat
1386  */
1387 #ifdef CONFIG_COMPAT
1388 #include "control_compat.c"
1389 #else
1390 #define snd_ctl_ioctl_compat    NULL
1391 #endif
1392
1393 /*
1394  *  INIT PART
1395  */
1396
1397 static const struct file_operations snd_ctl_f_ops =
1398 {
1399         .owner =        THIS_MODULE,
1400         .read =         snd_ctl_read,
1401         .open =         snd_ctl_open,
1402         .release =      snd_ctl_release,
1403         .poll =         snd_ctl_poll,
1404         .unlocked_ioctl =       snd_ctl_ioctl,
1405         .compat_ioctl = snd_ctl_ioctl_compat,
1406         .fasync =       snd_ctl_fasync,
1407 };
1408
1409 /*
1410  * registration of the control device
1411  */
1412 static int snd_ctl_dev_register(struct snd_device *device)
1413 {
1414         struct snd_card *card = device->device_data;
1415         int err, cardnum;
1416         char name[16];
1417
1418         if (snd_BUG_ON(!card))
1419                 return -ENXIO;
1420         cardnum = card->number;
1421         if (snd_BUG_ON(cardnum < 0 || cardnum >= SNDRV_CARDS))
1422                 return -ENXIO;
1423         sprintf(name, "controlC%i", cardnum);
1424         if ((err = snd_register_device(SNDRV_DEVICE_TYPE_CONTROL, card, -1,
1425                                        &snd_ctl_f_ops, card, name)) < 0)
1426                 return err;
1427         return 0;
1428 }
1429
1430 /*
1431  * disconnection of the control device
1432  */
1433 static int snd_ctl_dev_disconnect(struct snd_device *device)
1434 {
1435         struct snd_card *card = device->device_data;
1436         struct snd_ctl_file *ctl;
1437         int err, cardnum;
1438
1439         if (snd_BUG_ON(!card))
1440                 return -ENXIO;
1441         cardnum = card->number;
1442         if (snd_BUG_ON(cardnum < 0 || cardnum >= SNDRV_CARDS))
1443                 return -ENXIO;
1444
1445         read_lock(&card->ctl_files_rwlock);
1446         list_for_each_entry(ctl, &card->ctl_files, list) {
1447                 wake_up(&ctl->change_sleep);
1448                 kill_fasync(&ctl->fasync, SIGIO, POLL_ERR);
1449         }
1450         read_unlock(&card->ctl_files_rwlock);
1451
1452         if ((err = snd_unregister_device(SNDRV_DEVICE_TYPE_CONTROL,
1453                                          card, -1)) < 0)
1454                 return err;
1455         return 0;
1456 }
1457
1458 /*
1459  * free all controls
1460  */
1461 static int snd_ctl_dev_free(struct snd_device *device)
1462 {
1463         struct snd_card *card = device->device_data;
1464         struct snd_kcontrol *control;
1465
1466         down_write(&card->controls_rwsem);
1467         while (!list_empty(&card->controls)) {
1468                 control = snd_kcontrol(card->controls.next);
1469                 snd_ctl_remove(card, control);
1470         }
1471         up_write(&card->controls_rwsem);
1472         return 0;
1473 }
1474
1475 /*
1476  * create control core:
1477  * called from init.c
1478  */
1479 int snd_ctl_create(struct snd_card *card)
1480 {
1481         static struct snd_device_ops ops = {
1482                 .dev_free = snd_ctl_dev_free,
1483                 .dev_register = snd_ctl_dev_register,
1484                 .dev_disconnect = snd_ctl_dev_disconnect,
1485         };
1486
1487         if (snd_BUG_ON(!card))
1488                 return -ENXIO;
1489         return snd_device_new(card, SNDRV_DEV_CONTROL, card, &ops);
1490 }
1491
1492 /*
1493  * Frequently used control callbacks
1494  */
1495 int snd_ctl_boolean_mono_info(struct snd_kcontrol *kcontrol,
1496                               struct snd_ctl_elem_info *uinfo)
1497 {
1498         uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
1499         uinfo->count = 1;
1500         uinfo->value.integer.min = 0;
1501         uinfo->value.integer.max = 1;
1502         return 0;
1503 }
1504
1505 EXPORT_SYMBOL(snd_ctl_boolean_mono_info);
1506
1507 int snd_ctl_boolean_stereo_info(struct snd_kcontrol *kcontrol,
1508                                 struct snd_ctl_elem_info *uinfo)
1509 {
1510         uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
1511         uinfo->count = 2;
1512         uinfo->value.integer.min = 0;
1513         uinfo->value.integer.max = 1;
1514         return 0;
1515 }
1516
1517 EXPORT_SYMBOL(snd_ctl_boolean_stereo_info);