Merge branch 'tracing/core' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic...
[linux-2.6-block.git] / sound / core / sound.c
CommitLineData
1da177e4
LT
1/*
2 * Advanced Linux Sound Architecture
c1017a4c 3 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
1da177e4
LT
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
1da177e4
LT
22#include <linux/init.h>
23#include <linux/slab.h>
78a3c3d7 24#include <linux/smp_lock.h>
1da177e4 25#include <linux/time.h>
9a1a2a1d 26#include <linux/device.h>
1da177e4
LT
27#include <linux/moduleparam.h>
28#include <sound/core.h>
29#include <sound/minors.h>
30#include <sound/info.h>
31#include <sound/version.h>
32#include <sound/control.h>
33#include <sound/initval.h>
34#include <linux/kmod.h>
1a60d4c5 35#include <linux/mutex.h>
1da177e4 36
1da177e4
LT
37static int major = CONFIG_SND_MAJOR;
38int snd_major;
c0d3fb39
TI
39EXPORT_SYMBOL(snd_major);
40
1da177e4 41static int cards_limit = 1;
1da177e4 42
c1017a4c 43MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
1da177e4
LT
44MODULE_DESCRIPTION("Advanced Linux Sound Architecture driver for soundcards.");
45MODULE_LICENSE("GPL");
46module_param(major, int, 0444);
47MODULE_PARM_DESC(major, "Major # for sound driver.");
48module_param(cards_limit, int, 0444);
49MODULE_PARM_DESC(cards_limit, "Count of auto-loadable soundcards.");
1da177e4
LT
50MODULE_ALIAS_CHARDEV_MAJOR(CONFIG_SND_MAJOR);
51
52/* this one holds the actual max. card number currently available.
53 * as default, it's identical with cards_limit option. when more
54 * modules are loaded manually, this limit number increases, too.
55 */
56int snd_ecards_limit;
c0d3fb39 57EXPORT_SYMBOL(snd_ecards_limit);
1da177e4 58
6983b724 59static struct snd_minor *snd_minors[SNDRV_OS_MINORS];
1a60d4c5 60static DEFINE_MUTEX(sound_mutex);
1da177e4 61
ee2da997 62#ifdef CONFIG_MODULES
1da177e4
LT
63
64/**
65 * snd_request_card - try to load the card module
66 * @card: the card number
67 *
68 * Tries to load the module "snd-card-X" for the given card number
ee2da997 69 * via request_module. Returns immediately if already loaded.
1da177e4
LT
70 */
71void snd_request_card(int card)
72{
746df948 73 if (snd_card_locked(card))
1da177e4
LT
74 return;
75 if (card < 0 || card >= cards_limit)
76 return;
77 request_module("snd-card-%i", card);
78}
79
c0d3fb39
TI
80EXPORT_SYMBOL(snd_request_card);
81
1da177e4
LT
82static void snd_request_other(int minor)
83{
84 char *str;
85
1da177e4
LT
86 switch (minor) {
87 case SNDRV_MINOR_SEQUENCER: str = "snd-seq"; break;
88 case SNDRV_MINOR_TIMER: str = "snd-timer"; break;
89 default: return;
90 }
91 request_module(str);
92}
93
ee2da997 94#endif /* modular kernel */
1da177e4 95
f87135f5
CL
96/**
97 * snd_lookup_minor_data - get user data of a registered device
98 * @minor: the minor number
99 * @type: device type (SNDRV_DEVICE_TYPE_XXX)
100 *
101 * Checks that a minor device with the specified type is registered, and returns
102 * its user data pointer.
103 */
104void *snd_lookup_minor_data(unsigned int minor, int type)
105{
106 struct snd_minor *mreg;
107 void *private_data;
108
3a63e444 109 if (minor >= ARRAY_SIZE(snd_minors))
f87135f5 110 return NULL;
1a60d4c5 111 mutex_lock(&sound_mutex);
f87135f5
CL
112 mreg = snd_minors[minor];
113 if (mreg && mreg->type == type)
114 private_data = mreg->private_data;
115 else
116 private_data = NULL;
1a60d4c5 117 mutex_unlock(&sound_mutex);
f87135f5
CL
118 return private_data;
119}
120
c0d3fb39
TI
121EXPORT_SYMBOL(snd_lookup_minor_data);
122
78a3c3d7 123static int __snd_open(struct inode *inode, struct file *file)
1da177e4 124{
332682b1 125 unsigned int minor = iminor(inode);
512bbd6a 126 struct snd_minor *mptr = NULL;
99ac48f5 127 const struct file_operations *old_fops;
1da177e4
LT
128 int err = 0;
129
3a63e444 130 if (minor >= ARRAY_SIZE(snd_minors))
332682b1
CL
131 return -ENODEV;
132 mptr = snd_minors[minor];
133 if (mptr == NULL) {
ee2da997 134#ifdef CONFIG_MODULES
332682b1
CL
135 int dev = SNDRV_MINOR_DEVICE(minor);
136 if (dev == SNDRV_MINOR_CONTROL) {
137 /* /dev/aloadC? */
138 int card = SNDRV_MINOR_CARD(minor);
1da177e4 139 if (snd_cards[card] == NULL)
332682b1
CL
140 snd_request_card(card);
141 } else if (dev == SNDRV_MINOR_GLOBAL) {
142 /* /dev/aloadSEQ */
1da177e4 143 snd_request_other(minor);
332682b1
CL
144 }
145#ifndef CONFIG_SND_DYNAMIC_MINORS
146 /* /dev/snd/{controlC?,seq} */
147 mptr = snd_minors[minor];
148 if (mptr == NULL)
149#endif
1da177e4 150#endif
332682b1 151 return -ENODEV;
1da177e4 152 }
1da177e4
LT
153 old_fops = file->f_op;
154 file->f_op = fops_get(mptr->f_ops);
f41ced8f
LP
155 if (file->f_op == NULL) {
156 file->f_op = old_fops;
157 return -ENODEV;
158 }
1da177e4
LT
159 if (file->f_op->open)
160 err = file->f_op->open(inode, file);
161 if (err) {
162 fops_put(file->f_op);
163 file->f_op = fops_get(old_fops);
164 }
165 fops_put(old_fops);
166 return err;
167}
168
78a3c3d7
JC
169
170/* BKL pushdown: nasty #ifdef avoidance wrapper */
171static int snd_open(struct inode *inode, struct file *file)
172{
173 int ret;
174
175 lock_kernel();
176 ret = __snd_open(inode, file);
177 unlock_kernel();
178 return ret;
179}
180
9c2e08c5 181static const struct file_operations snd_fops =
1da177e4
LT
182{
183 .owner = THIS_MODULE,
184 .open = snd_open
185};
186
332682b1
CL
187#ifdef CONFIG_SND_DYNAMIC_MINORS
188static int snd_find_free_minor(void)
189{
190 int minor;
191
192 for (minor = 0; minor < ARRAY_SIZE(snd_minors); ++minor) {
193 /* skip minors still used statically for autoloading devices */
194 if (SNDRV_MINOR_DEVICE(minor) == SNDRV_MINOR_CONTROL ||
195 minor == SNDRV_MINOR_SEQUENCER)
196 continue;
197 if (!snd_minors[minor])
198 return minor;
199 }
200 return -EBUSY;
201}
202#else
512bbd6a 203static int snd_kernel_minor(int type, struct snd_card *card, int dev)
1da177e4
LT
204{
205 int minor;
206
207 switch (type) {
208 case SNDRV_DEVICE_TYPE_SEQUENCER:
209 case SNDRV_DEVICE_TYPE_TIMER:
210 minor = type;
211 break;
212 case SNDRV_DEVICE_TYPE_CONTROL:
7eaa943c
TI
213 if (snd_BUG_ON(!card))
214 return -EINVAL;
1da177e4
LT
215 minor = SNDRV_MINOR(card->number, type);
216 break;
217 case SNDRV_DEVICE_TYPE_HWDEP:
218 case SNDRV_DEVICE_TYPE_RAWMIDI:
219 case SNDRV_DEVICE_TYPE_PCM_PLAYBACK:
220 case SNDRV_DEVICE_TYPE_PCM_CAPTURE:
7eaa943c
TI
221 if (snd_BUG_ON(!card))
222 return -EINVAL;
1da177e4
LT
223 minor = SNDRV_MINOR(card->number, type + dev);
224 break;
225 default:
226 return -EINVAL;
227 }
7eaa943c
TI
228 if (snd_BUG_ON(minor < 0 || minor >= SNDRV_OS_MINORS))
229 return -EINVAL;
1da177e4
LT
230 return minor;
231}
332682b1 232#endif
1da177e4
LT
233
234/**
12b131c4 235 * snd_register_device_for_dev - Register the ALSA device file for the card
1da177e4
LT
236 * @type: the device type, SNDRV_DEVICE_TYPE_XXX
237 * @card: the card instance
238 * @dev: the device index
2af677fc 239 * @f_ops: the file operations
f87135f5 240 * @private_data: user pointer for f_ops->open()
1da177e4 241 * @name: the device file name
12b131c4 242 * @device: the &struct device to link this new device to
1da177e4
LT
243 *
244 * Registers an ALSA device file for the given card.
245 * The operators have to be set in reg parameter.
246 *
12b131c4 247 * Returns zero if successful, or a negative error code on failure.
1da177e4 248 */
12b131c4
JB
249int snd_register_device_for_dev(int type, struct snd_card *card, int dev,
250 const struct file_operations *f_ops,
251 void *private_data,
252 const char *name, struct device *device)
1da177e4 253{
332682b1 254 int minor;
512bbd6a 255 struct snd_minor *preg;
1da177e4 256
7eaa943c
TI
257 if (snd_BUG_ON(!name))
258 return -EINVAL;
562b590d 259 preg = kmalloc(sizeof *preg, GFP_KERNEL);
1da177e4
LT
260 if (preg == NULL)
261 return -ENOMEM;
2af677fc 262 preg->type = type;
6983b724 263 preg->card = card ? card->number : -1;
1da177e4 264 preg->device = dev;
2af677fc 265 preg->f_ops = f_ops;
f87135f5 266 preg->private_data = private_data;
1a60d4c5 267 mutex_lock(&sound_mutex);
332682b1
CL
268#ifdef CONFIG_SND_DYNAMIC_MINORS
269 minor = snd_find_free_minor();
270#else
271 minor = snd_kernel_minor(type, card, dev);
272 if (minor >= 0 && snd_minors[minor])
273 minor = -EBUSY;
274#endif
275 if (minor < 0) {
1a60d4c5 276 mutex_unlock(&sound_mutex);
1da177e4 277 kfree(preg);
332682b1 278 return minor;
1da177e4 279 }
6983b724 280 snd_minors[minor] = preg;
abe9ab8f
GKH
281 preg->dev = device_create(sound_class, device, MKDEV(major, minor),
282 private_data, "%s", name);
2469049e
MK
283 if (IS_ERR(preg->dev)) {
284 snd_minors[minor] = NULL;
285 mutex_unlock(&sound_mutex);
286 minor = PTR_ERR(preg->dev);
287 kfree(preg);
288 return minor;
289 }
290
1a60d4c5 291 mutex_unlock(&sound_mutex);
1da177e4
LT
292 return 0;
293}
294
12b131c4 295EXPORT_SYMBOL(snd_register_device_for_dev);
c0d3fb39 296
9d19f48c
TI
297/* find the matching minor record
298 * return the index of snd_minor, or -1 if not found
299 */
300static int find_snd_minor(int type, struct snd_card *card, int dev)
301{
302 int cardnum, minor;
303 struct snd_minor *mptr;
304
305 cardnum = card ? card->number : -1;
306 for (minor = 0; minor < ARRAY_SIZE(snd_minors); ++minor)
307 if ((mptr = snd_minors[minor]) != NULL &&
308 mptr->type == type &&
309 mptr->card == cardnum &&
310 mptr->device == dev)
311 return minor;
312 return -1;
313}
314
1da177e4
LT
315/**
316 * snd_unregister_device - unregister the device on the given card
317 * @type: the device type, SNDRV_DEVICE_TYPE_XXX
318 * @card: the card instance
319 * @dev: the device index
320 *
321 * Unregisters the device file already registered via
322 * snd_register_device().
323 *
324 * Returns zero if sucecessful, or a negative error code on failure
325 */
512bbd6a 326int snd_unregister_device(int type, struct snd_card *card, int dev)
1da177e4 327{
9d19f48c 328 int minor;
1da177e4 329
1a60d4c5 330 mutex_lock(&sound_mutex);
9d19f48c
TI
331 minor = find_snd_minor(type, card, dev);
332 if (minor < 0) {
1a60d4c5 333 mutex_unlock(&sound_mutex);
1da177e4
LT
334 return -EINVAL;
335 }
336
d80f19fa 337 device_destroy(sound_class, MKDEV(major, minor));
1da177e4 338
9d19f48c 339 kfree(snd_minors[minor]);
6983b724 340 snd_minors[minor] = NULL;
1a60d4c5 341 mutex_unlock(&sound_mutex);
1da177e4
LT
342 return 0;
343}
344
c0d3fb39
TI
345EXPORT_SYMBOL(snd_unregister_device);
346
9d19f48c 347int snd_add_device_sysfs_file(int type, struct snd_card *card, int dev,
d80f19fa 348 struct device_attribute *attr)
9d19f48c
TI
349{
350 int minor, ret = -EINVAL;
d80f19fa 351 struct device *d;
9d19f48c
TI
352
353 mutex_lock(&sound_mutex);
354 minor = find_snd_minor(type, card, dev);
d80f19fa
GKH
355 if (minor >= 0 && (d = snd_minors[minor]->dev) != NULL)
356 ret = device_create_file(d, attr);
9d19f48c
TI
357 mutex_unlock(&sound_mutex);
358 return ret;
359
360}
361
362EXPORT_SYMBOL(snd_add_device_sysfs_file);
363
e28563cc 364#ifdef CONFIG_PROC_FS
1da177e4
LT
365/*
366 * INFO PART
367 */
368
6581f4e7 369static struct snd_info_entry *snd_minor_info_entry;
1da177e4 370
2af677fc
CL
371static const char *snd_device_type_name(int type)
372{
373 switch (type) {
374 case SNDRV_DEVICE_TYPE_CONTROL:
375 return "control";
376 case SNDRV_DEVICE_TYPE_HWDEP:
377 return "hardware dependent";
378 case SNDRV_DEVICE_TYPE_RAWMIDI:
379 return "raw midi";
380 case SNDRV_DEVICE_TYPE_PCM_PLAYBACK:
381 return "digital audio playback";
382 case SNDRV_DEVICE_TYPE_PCM_CAPTURE:
383 return "digital audio capture";
384 case SNDRV_DEVICE_TYPE_SEQUENCER:
385 return "sequencer";
386 case SNDRV_DEVICE_TYPE_TIMER:
387 return "timer";
388 default:
389 return "?";
390 }
391}
392
512bbd6a 393static void snd_minor_info_read(struct snd_info_entry *entry, struct snd_info_buffer *buffer)
1da177e4 394{
6983b724 395 int minor;
512bbd6a 396 struct snd_minor *mptr;
1da177e4 397
1a60d4c5 398 mutex_lock(&sound_mutex);
6983b724
CL
399 for (minor = 0; minor < SNDRV_OS_MINORS; ++minor) {
400 if (!(mptr = snd_minors[minor]))
401 continue;
402 if (mptr->card >= 0) {
403 if (mptr->device >= 0)
d001544d 404 snd_iprintf(buffer, "%3i: [%2i-%2i]: %s\n",
6983b724
CL
405 minor, mptr->card, mptr->device,
406 snd_device_type_name(mptr->type));
407 else
d001544d 408 snd_iprintf(buffer, "%3i: [%2i] : %s\n",
6983b724
CL
409 minor, mptr->card,
410 snd_device_type_name(mptr->type));
411 } else
d001544d 412 snd_iprintf(buffer, "%3i: : %s\n", minor,
6983b724 413 snd_device_type_name(mptr->type));
1da177e4 414 }
1a60d4c5 415 mutex_unlock(&sound_mutex);
1da177e4
LT
416}
417
418int __init snd_minor_info_init(void)
419{
512bbd6a 420 struct snd_info_entry *entry;
1da177e4
LT
421
422 entry = snd_info_create_module_entry(THIS_MODULE, "devices", NULL);
423 if (entry) {
1da177e4
LT
424 entry->c.text.read = snd_minor_info_read;
425 if (snd_info_register(entry) < 0) {
426 snd_info_free_entry(entry);
427 entry = NULL;
428 }
429 }
430 snd_minor_info_entry = entry;
431 return 0;
432}
433
434int __exit snd_minor_info_done(void)
435{
746d4a02 436 snd_info_free_entry(snd_minor_info_entry);
1da177e4
LT
437 return 0;
438}
e28563cc 439#endif /* CONFIG_PROC_FS */
1da177e4
LT
440
441/*
442 * INIT PART
443 */
444
445static int __init alsa_sound_init(void)
446{
1da177e4
LT
447 snd_major = major;
448 snd_ecards_limit = cards_limit;
1da177e4
LT
449 if (register_chrdev(major, "alsa", &snd_fops)) {
450 snd_printk(KERN_ERR "unable to register native major device number %d\n", major);
1da177e4
LT
451 return -EIO;
452 }
1da177e4 453 if (snd_info_init() < 0) {
1da177e4 454 unregister_chrdev(major, "alsa");
1da177e4
LT
455 return -ENOMEM;
456 }
457 snd_info_minor_register();
1da177e4
LT
458#ifndef MODULE
459 printk(KERN_INFO "Advanced Linux Sound Architecture Driver Version " CONFIG_SND_VERSION CONFIG_SND_DATE ".\n");
460#endif
461 return 0;
462}
463
464static void __exit alsa_sound_exit(void)
465{
1da177e4
LT
466 snd_info_minor_unregister();
467 snd_info_done();
68fc4fab 468 unregister_chrdev(major, "alsa");
1da177e4
LT
469}
470
c181a13a
TLSC
471subsys_initcall(alsa_sound_init);
472module_exit(alsa_sound_exit);