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