ALSA: Add a reference counter to card instance
[pandora-kernel.git] / sound / core / hwdep.c
1 /*
2  *  Hardware dependent layer
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/major.h>
23 #include <linux/init.h>
24 #include <linux/slab.h>
25 #include <linux/time.h>
26 #include <linux/mutex.h>
27 #include <linux/module.h>
28 #include <sound/core.h>
29 #include <sound/control.h>
30 #include <sound/minors.h>
31 #include <sound/hwdep.h>
32 #include <sound/info.h>
33
34 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
35 MODULE_DESCRIPTION("Hardware dependent layer");
36 MODULE_LICENSE("GPL");
37
38 static LIST_HEAD(snd_hwdep_devices);
39 static DEFINE_MUTEX(register_mutex);
40
41 static int snd_hwdep_free(struct snd_hwdep *hwdep);
42 static int snd_hwdep_dev_free(struct snd_device *device);
43 static int snd_hwdep_dev_register(struct snd_device *device);
44 static int snd_hwdep_dev_disconnect(struct snd_device *device);
45
46
47 static struct snd_hwdep *snd_hwdep_search(struct snd_card *card, int device)
48 {
49         struct snd_hwdep *hwdep;
50
51         list_for_each_entry(hwdep, &snd_hwdep_devices, list)
52                 if (hwdep->card == card && hwdep->device == device)
53                         return hwdep;
54         return NULL;
55 }
56
57 static loff_t snd_hwdep_llseek(struct file * file, loff_t offset, int orig)
58 {
59         struct snd_hwdep *hw = file->private_data;
60         if (hw->ops.llseek)
61                 return hw->ops.llseek(hw, file, offset, orig);
62         return -ENXIO;
63 }
64
65 static ssize_t snd_hwdep_read(struct file * file, char __user *buf,
66                               size_t count, loff_t *offset)
67 {
68         struct snd_hwdep *hw = file->private_data;
69         if (hw->ops.read)
70                 return hw->ops.read(hw, buf, count, offset);
71         return -ENXIO;  
72 }
73
74 static ssize_t snd_hwdep_write(struct file * file, const char __user *buf,
75                                size_t count, loff_t *offset)
76 {
77         struct snd_hwdep *hw = file->private_data;
78         if (hw->ops.write)
79                 return hw->ops.write(hw, buf, count, offset);
80         return -ENXIO;  
81 }
82
83 static int snd_hwdep_open(struct inode *inode, struct file * file)
84 {
85         int major = imajor(inode);
86         struct snd_hwdep *hw;
87         int err;
88         wait_queue_t wait;
89
90         if (major == snd_major) {
91                 hw = snd_lookup_minor_data(iminor(inode),
92                                            SNDRV_DEVICE_TYPE_HWDEP);
93 #ifdef CONFIG_SND_OSSEMUL
94         } else if (major == SOUND_MAJOR) {
95                 hw = snd_lookup_oss_minor_data(iminor(inode),
96                                                SNDRV_OSS_DEVICE_TYPE_DMFM);
97 #endif
98         } else
99                 return -ENXIO;
100         if (hw == NULL)
101                 return -ENODEV;
102
103         if (!try_module_get(hw->card->module)) {
104                 snd_card_unref(hw->card);
105                 return -EFAULT;
106         }
107
108         init_waitqueue_entry(&wait, current);
109         add_wait_queue(&hw->open_wait, &wait);
110         mutex_lock(&hw->open_mutex);
111         while (1) {
112                 if (hw->exclusive && hw->used > 0) {
113                         err = -EBUSY;
114                         break;
115                 }
116                 if (!hw->ops.open) {
117                         err = 0;
118                         break;
119                 }
120                 err = hw->ops.open(hw, file);
121                 if (err >= 0)
122                         break;
123                 if (err == -EAGAIN) {
124                         if (file->f_flags & O_NONBLOCK) {
125                                 err = -EBUSY;
126                                 break;
127                         }
128                 } else
129                         break;
130                 set_current_state(TASK_INTERRUPTIBLE);
131                 mutex_unlock(&hw->open_mutex);
132                 schedule();
133                 mutex_lock(&hw->open_mutex);
134                 if (signal_pending(current)) {
135                         err = -ERESTARTSYS;
136                         break;
137                 }
138         }
139         remove_wait_queue(&hw->open_wait, &wait);
140         if (err >= 0) {
141                 err = snd_card_file_add(hw->card, file);
142                 if (err >= 0) {
143                         file->private_data = hw;
144                         hw->used++;
145                 } else {
146                         if (hw->ops.release)
147                                 hw->ops.release(hw, file);
148                 }
149         }
150         mutex_unlock(&hw->open_mutex);
151         if (err < 0)
152                 module_put(hw->card->module);
153         snd_card_unref(hw->card);
154         return err;
155 }
156
157 static int snd_hwdep_release(struct inode *inode, struct file * file)
158 {
159         int err = 0;
160         struct snd_hwdep *hw = file->private_data;
161         struct module *mod = hw->card->module;
162
163         mutex_lock(&hw->open_mutex);
164         if (hw->ops.release)
165                 err = hw->ops.release(hw, file);
166         if (hw->used > 0)
167                 hw->used--;
168         mutex_unlock(&hw->open_mutex);
169         wake_up(&hw->open_wait);
170
171         snd_card_file_remove(hw->card, file);
172         module_put(mod);
173         return err;
174 }
175
176 static unsigned int snd_hwdep_poll(struct file * file, poll_table * wait)
177 {
178         struct snd_hwdep *hw = file->private_data;
179         if (hw->ops.poll)
180                 return hw->ops.poll(hw, file, wait);
181         return 0;
182 }
183
184 static int snd_hwdep_info(struct snd_hwdep *hw,
185                           struct snd_hwdep_info __user *_info)
186 {
187         struct snd_hwdep_info info;
188         
189         memset(&info, 0, sizeof(info));
190         info.card = hw->card->number;
191         strlcpy(info.id, hw->id, sizeof(info.id));      
192         strlcpy(info.name, hw->name, sizeof(info.name));
193         info.iface = hw->iface;
194         if (copy_to_user(_info, &info, sizeof(info)))
195                 return -EFAULT;
196         return 0;
197 }
198
199 static int snd_hwdep_dsp_status(struct snd_hwdep *hw,
200                                 struct snd_hwdep_dsp_status __user *_info)
201 {
202         struct snd_hwdep_dsp_status info;
203         int err;
204         
205         if (! hw->ops.dsp_status)
206                 return -ENXIO;
207         memset(&info, 0, sizeof(info));
208         info.dsp_loaded = hw->dsp_loaded;
209         if ((err = hw->ops.dsp_status(hw, &info)) < 0)
210                 return err;
211         if (copy_to_user(_info, &info, sizeof(info)))
212                 return -EFAULT;
213         return 0;
214 }
215
216 static int snd_hwdep_dsp_load(struct snd_hwdep *hw,
217                               struct snd_hwdep_dsp_image __user *_info)
218 {
219         struct snd_hwdep_dsp_image info;
220         int err;
221         
222         if (! hw->ops.dsp_load)
223                 return -ENXIO;
224         memset(&info, 0, sizeof(info));
225         if (copy_from_user(&info, _info, sizeof(info)))
226                 return -EFAULT;
227         /* check whether the dsp was already loaded */
228         if (hw->dsp_loaded & (1 << info.index))
229                 return -EBUSY;
230         if (!access_ok(VERIFY_READ, info.image, info.length))
231                 return -EFAULT;
232         err = hw->ops.dsp_load(hw, &info);
233         if (err < 0)
234                 return err;
235         hw->dsp_loaded |= (1 << info.index);
236         return 0;
237 }
238
239 static long snd_hwdep_ioctl(struct file * file, unsigned int cmd,
240                             unsigned long arg)
241 {
242         struct snd_hwdep *hw = file->private_data;
243         void __user *argp = (void __user *)arg;
244         switch (cmd) {
245         case SNDRV_HWDEP_IOCTL_PVERSION:
246                 return put_user(SNDRV_HWDEP_VERSION, (int __user *)argp);
247         case SNDRV_HWDEP_IOCTL_INFO:
248                 return snd_hwdep_info(hw, argp);
249         case SNDRV_HWDEP_IOCTL_DSP_STATUS:
250                 return snd_hwdep_dsp_status(hw, argp);
251         case SNDRV_HWDEP_IOCTL_DSP_LOAD:
252                 return snd_hwdep_dsp_load(hw, argp);
253         }
254         if (hw->ops.ioctl)
255                 return hw->ops.ioctl(hw, file, cmd, arg);
256         return -ENOTTY;
257 }
258
259 static int snd_hwdep_mmap(struct file * file, struct vm_area_struct * vma)
260 {
261         struct snd_hwdep *hw = file->private_data;
262         if (hw->ops.mmap)
263                 return hw->ops.mmap(hw, file, vma);
264         return -ENXIO;
265 }
266
267 static int snd_hwdep_control_ioctl(struct snd_card *card,
268                                    struct snd_ctl_file * control,
269                                    unsigned int cmd, unsigned long arg)
270 {
271         switch (cmd) {
272         case SNDRV_CTL_IOCTL_HWDEP_NEXT_DEVICE:
273                 {
274                         int device;
275
276                         if (get_user(device, (int __user *)arg))
277                                 return -EFAULT;
278                         mutex_lock(&register_mutex);
279
280                         if (device < 0)
281                                 device = 0;
282                         else if (device < SNDRV_MINOR_HWDEPS)
283                                 device++;
284                         else
285                                 device = SNDRV_MINOR_HWDEPS;
286
287                         while (device < SNDRV_MINOR_HWDEPS) {
288                                 if (snd_hwdep_search(card, device))
289                                         break;
290                                 device++;
291                         }
292                         if (device >= SNDRV_MINOR_HWDEPS)
293                                 device = -1;
294                         mutex_unlock(&register_mutex);
295                         if (put_user(device, (int __user *)arg))
296                                 return -EFAULT;
297                         return 0;
298                 }
299         case SNDRV_CTL_IOCTL_HWDEP_INFO:
300                 {
301                         struct snd_hwdep_info __user *info = (struct snd_hwdep_info __user *)arg;
302                         int device, err;
303                         struct snd_hwdep *hwdep;
304
305                         if (get_user(device, &info->device))
306                                 return -EFAULT;
307                         mutex_lock(&register_mutex);
308                         hwdep = snd_hwdep_search(card, device);
309                         if (hwdep)
310                                 err = snd_hwdep_info(hwdep, info);
311                         else
312                                 err = -ENXIO;
313                         mutex_unlock(&register_mutex);
314                         return err;
315                 }
316         }
317         return -ENOIOCTLCMD;
318 }
319
320 #ifdef CONFIG_COMPAT
321 #include "hwdep_compat.c"
322 #else
323 #define snd_hwdep_ioctl_compat  NULL
324 #endif
325
326 /*
327
328  */
329
330 static const struct file_operations snd_hwdep_f_ops =
331 {
332         .owner =        THIS_MODULE,
333         .llseek =       snd_hwdep_llseek,
334         .read =         snd_hwdep_read,
335         .write =        snd_hwdep_write,
336         .open =         snd_hwdep_open,
337         .release =      snd_hwdep_release,
338         .poll =         snd_hwdep_poll,
339         .unlocked_ioctl =       snd_hwdep_ioctl,
340         .compat_ioctl = snd_hwdep_ioctl_compat,
341         .mmap =         snd_hwdep_mmap,
342 };
343
344 /**
345  * snd_hwdep_new - create a new hwdep instance
346  * @card: the card instance
347  * @id: the id string
348  * @device: the device index (zero-based)
349  * @rhwdep: the pointer to store the new hwdep instance
350  *
351  * Creates a new hwdep instance with the given index on the card.
352  * The callbacks (hwdep->ops) must be set on the returned instance
353  * after this call manually by the caller.
354  *
355  * Returns zero if successful, or a negative error code on failure.
356  */
357 int snd_hwdep_new(struct snd_card *card, char *id, int device,
358                   struct snd_hwdep **rhwdep)
359 {
360         struct snd_hwdep *hwdep;
361         int err;
362         static struct snd_device_ops ops = {
363                 .dev_free = snd_hwdep_dev_free,
364                 .dev_register = snd_hwdep_dev_register,
365                 .dev_disconnect = snd_hwdep_dev_disconnect,
366         };
367
368         if (snd_BUG_ON(!card))
369                 return -ENXIO;
370         if (rhwdep)
371                 *rhwdep = NULL;
372         hwdep = kzalloc(sizeof(*hwdep), GFP_KERNEL);
373         if (hwdep == NULL) {
374                 snd_printk(KERN_ERR "hwdep: cannot allocate\n");
375                 return -ENOMEM;
376         }
377         hwdep->card = card;
378         hwdep->device = device;
379         if (id)
380                 strlcpy(hwdep->id, id, sizeof(hwdep->id));
381 #ifdef CONFIG_SND_OSSEMUL
382         hwdep->oss_type = -1;
383 #endif
384         if ((err = snd_device_new(card, SNDRV_DEV_HWDEP, hwdep, &ops)) < 0) {
385                 snd_hwdep_free(hwdep);
386                 return err;
387         }
388         init_waitqueue_head(&hwdep->open_wait);
389         mutex_init(&hwdep->open_mutex);
390         if (rhwdep)
391                 *rhwdep = hwdep;
392         return 0;
393 }
394
395 static int snd_hwdep_free(struct snd_hwdep *hwdep)
396 {
397         if (!hwdep)
398                 return 0;
399         if (hwdep->private_free)
400                 hwdep->private_free(hwdep);
401         kfree(hwdep);
402         return 0;
403 }
404
405 static int snd_hwdep_dev_free(struct snd_device *device)
406 {
407         struct snd_hwdep *hwdep = device->device_data;
408         return snd_hwdep_free(hwdep);
409 }
410
411 static int snd_hwdep_dev_register(struct snd_device *device)
412 {
413         struct snd_hwdep *hwdep = device->device_data;
414         int err;
415         char name[32];
416
417         mutex_lock(&register_mutex);
418         if (snd_hwdep_search(hwdep->card, hwdep->device)) {
419                 mutex_unlock(&register_mutex);
420                 return -EBUSY;
421         }
422         list_add_tail(&hwdep->list, &snd_hwdep_devices);
423         sprintf(name, "hwC%iD%i", hwdep->card->number, hwdep->device);
424         if ((err = snd_register_device(SNDRV_DEVICE_TYPE_HWDEP,
425                                        hwdep->card, hwdep->device,
426                                        &snd_hwdep_f_ops, hwdep, name)) < 0) {
427                 snd_printk(KERN_ERR "unable to register hardware dependent device %i:%i\n",
428                            hwdep->card->number, hwdep->device);
429                 list_del(&hwdep->list);
430                 mutex_unlock(&register_mutex);
431                 return err;
432         }
433 #ifdef CONFIG_SND_OSSEMUL
434         hwdep->ossreg = 0;
435         if (hwdep->oss_type >= 0) {
436                 if ((hwdep->oss_type == SNDRV_OSS_DEVICE_TYPE_DMFM) && (hwdep->device != 0)) {
437                         snd_printk (KERN_WARNING "only hwdep device 0 can be registered as OSS direct FM device!\n");
438                 } else {
439                         if (snd_register_oss_device(hwdep->oss_type,
440                                                     hwdep->card, hwdep->device,
441                                                     &snd_hwdep_f_ops, hwdep,
442                                                     hwdep->oss_dev) < 0) {
443                                 snd_printk(KERN_ERR "unable to register OSS compatibility device %i:%i\n",
444                                            hwdep->card->number, hwdep->device);
445                         } else
446                                 hwdep->ossreg = 1;
447                 }
448         }
449 #endif
450         mutex_unlock(&register_mutex);
451         return 0;
452 }
453
454 static int snd_hwdep_dev_disconnect(struct snd_device *device)
455 {
456         struct snd_hwdep *hwdep = device->device_data;
457
458         if (snd_BUG_ON(!hwdep))
459                 return -ENXIO;
460         mutex_lock(&register_mutex);
461         if (snd_hwdep_search(hwdep->card, hwdep->device) != hwdep) {
462                 mutex_unlock(&register_mutex);
463                 return -EINVAL;
464         }
465 #ifdef CONFIG_SND_OSSEMUL
466         if (hwdep->ossreg)
467                 snd_unregister_oss_device(hwdep->oss_type, hwdep->card, hwdep->device);
468 #endif
469         snd_unregister_device(SNDRV_DEVICE_TYPE_HWDEP, hwdep->card, hwdep->device);
470         list_del_init(&hwdep->list);
471         mutex_unlock(&register_mutex);
472         return 0;
473 }
474
475 #ifdef CONFIG_PROC_FS
476 /*
477  *  Info interface
478  */
479
480 static void snd_hwdep_proc_read(struct snd_info_entry *entry,
481                                 struct snd_info_buffer *buffer)
482 {
483         struct snd_hwdep *hwdep;
484
485         mutex_lock(&register_mutex);
486         list_for_each_entry(hwdep, &snd_hwdep_devices, list)
487                 snd_iprintf(buffer, "%02i-%02i: %s\n",
488                             hwdep->card->number, hwdep->device, hwdep->name);
489         mutex_unlock(&register_mutex);
490 }
491
492 static struct snd_info_entry *snd_hwdep_proc_entry;
493
494 static void __init snd_hwdep_proc_init(void)
495 {
496         struct snd_info_entry *entry;
497
498         if ((entry = snd_info_create_module_entry(THIS_MODULE, "hwdep", NULL)) != NULL) {
499                 entry->c.text.read = snd_hwdep_proc_read;
500                 if (snd_info_register(entry) < 0) {
501                         snd_info_free_entry(entry);
502                         entry = NULL;
503                 }
504         }
505         snd_hwdep_proc_entry = entry;
506 }
507
508 static void __exit snd_hwdep_proc_done(void)
509 {
510         snd_info_free_entry(snd_hwdep_proc_entry);
511 }
512 #else /* !CONFIG_PROC_FS */
513 #define snd_hwdep_proc_init()
514 #define snd_hwdep_proc_done()
515 #endif /* CONFIG_PROC_FS */
516
517
518 /*
519  *  ENTRY functions
520  */
521
522 static int __init alsa_hwdep_init(void)
523 {
524         snd_hwdep_proc_init();
525         snd_ctl_register_ioctl(snd_hwdep_control_ioctl);
526         snd_ctl_register_ioctl_compat(snd_hwdep_control_ioctl);
527         return 0;
528 }
529
530 static void __exit alsa_hwdep_exit(void)
531 {
532         snd_ctl_unregister_ioctl(snd_hwdep_control_ioctl);
533         snd_ctl_unregister_ioctl_compat(snd_hwdep_control_ioctl);
534         snd_hwdep_proc_done();
535 }
536
537 module_init(alsa_hwdep_init)
538 module_exit(alsa_hwdep_exit)
539
540 EXPORT_SYMBOL(snd_hwdep_new);