summaryrefslogtreecommitdiff
path: root/sound/core/sound.c
blob: dee602245fe8cd1a7b60fd0cd14a0be8b5f497b2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
/*
 *  Advanced Linux Sound Architecture
 *  Copyright (c) by Jaroslav Kysela <perex@suse.cz>
 *
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 *
 */

#include <sound/driver.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/time.h>
#include <linux/moduleparam.h>
#include <sound/core.h>
#include <sound/minors.h>
#include <sound/info.h>
#include <sound/version.h>
#include <sound/control.h>
#include <sound/initval.h>
#include <linux/kmod.h>
#include <linux/devfs_fs_kernel.h>
#include <linux/device.h>

#define SNDRV_OS_MINORS 256

static int major = CONFIG_SND_MAJOR;
int snd_major;
static int cards_limit = 1;
static int device_mode = S_IFCHR | S_IRUGO | S_IWUGO;

MODULE_AUTHOR("Jaroslav Kysela <perex@suse.cz>");
MODULE_DESCRIPTION("Advanced Linux Sound Architecture driver for soundcards.");
MODULE_LICENSE("GPL");
module_param(major, int, 0444);
MODULE_PARM_DESC(major, "Major # for sound driver.");
module_param(cards_limit, int, 0444);
MODULE_PARM_DESC(cards_limit, "Count of auto-loadable soundcards.");
#ifdef CONFIG_DEVFS_FS
module_param(device_mode, int, 0444);
MODULE_PARM_DESC(device_mode, "Device file permission mask for devfs.");
#endif
MODULE_ALIAS_CHARDEV_MAJOR(CONFIG_SND_MAJOR);

/* this one holds the actual max. card number currently available.
 * as default, it's identical with cards_limit option.  when more
 * modules are loaded manually, this limit number increases, too.
 */
int snd_ecards_limit;

static struct list_head snd_minors_hash[SNDRV_CARDS];

static DECLARE_MUTEX(sound_mutex);

extern struct class *sound_class;


#ifdef CONFIG_KMOD

/**
 * snd_request_card - try to load the card module
 * @card: the card number
 *
 * Tries to load the module "snd-card-X" for the given card number
 * via KMOD.  Returns immediately if already loaded.
 */
void snd_request_card(int card)
{
	int locked;

	if (! current->fs->root)
		return;
	read_lock(&snd_card_rwlock);
	locked = snd_cards_lock & (1 << card);
	read_unlock(&snd_card_rwlock);
	if (locked)
		return;
	if (card < 0 || card >= cards_limit)
		return;
	request_module("snd-card-%i", card);
}

static void snd_request_other(int minor)
{
	char *str;

	if (! current->fs->root)
		return;
	switch (minor) {
	case SNDRV_MINOR_SEQUENCER:	str = "snd-seq";	break;
	case SNDRV_MINOR_TIMER:		str = "snd-timer";	break;
	default:			return;
	}
	request_module(str);
}

#endif				/* request_module support */

static snd_minor_t *snd_minor_search(int minor)
{
	struct list_head *list;
	snd_minor_t *mptr;

	list_for_each(list, &snd_minors_hash[SNDRV_MINOR_CARD(minor)]) {
		mptr = list_entry(list, snd_minor_t, list);
		if (mptr->number == minor)
			return mptr;
	}
	return NULL;
}

static int snd_open(struct inode *inode, struct file *file)
{
	int minor = iminor(inode);
	int card = SNDRV_MINOR_CARD(minor);
	int dev = SNDRV_MINOR_DEVICE(minor);
	snd_minor_t *mptr = NULL;
	struct file_operations *old_fops;
	int err = 0;

	if (dev != SNDRV_MINOR_SEQUENCER && dev != SNDRV_MINOR_TIMER) {
		if (snd_cards[card] == NULL) {
#ifdef CONFIG_KMOD
			snd_request_card(card);
			if (snd_cards[card] == NULL)
#endif
				return -ENODEV;
		}
	} else {
#ifdef CONFIG_KMOD
		if ((mptr = snd_minor_search(minor)) == NULL)
			snd_request_other(minor);
#endif
	}
	if (mptr == NULL && (mptr = snd_minor_search(minor)) == NULL)
		return -ENODEV;
	old_fops = file->f_op;
	file->f_op = fops_get(mptr->f_ops);
	if (file->f_op->open)
		err = file->f_op->open(inode, file);
	if (err) {
		fops_put(file->f_op);
		file->f_op = fops_get(old_fops);
	}
	fops_put(old_fops);
	return err;
}

static struct file_operations snd_fops =
{
	.owner =	THIS_MODULE,
	.open =		snd_open
};

static int snd_kernel_minor(int type, snd_card_t * card, int dev)
{
	int minor;

	switch (type) {
	case SNDRV_DEVICE_TYPE_SEQUENCER:
	case SNDRV_DEVICE_TYPE_TIMER:
		minor = type;
		break;
	case SNDRV_DEVICE_TYPE_CONTROL:
		snd_assert(card != NULL, return -EINVAL);
		minor = SNDRV_MINOR(card->number, type);
		break;
	case SNDRV_DEVICE_TYPE_HWDEP:
	case SNDRV_DEVICE_TYPE_RAWMIDI:
	case SNDRV_DEVICE_TYPE_PCM_PLAYBACK:
	case SNDRV_DEVICE_TYPE_PCM_CAPTURE:
		snd_assert(card != NULL, return -EINVAL);
		minor = SNDRV_MINOR(card->number, type + dev);
		break;
	default:
		return -EINVAL;
	}
	snd_assert(minor >= 0 && minor < SNDRV_OS_MINORS, return -EINVAL);
	return minor;
}

/**
 * snd_register_device - Register the ALSA device file for the card
 * @type: the device type, SNDRV_DEVICE_TYPE_XXX
 * @card: the card instance
 * @dev: the device index
 * @reg: the snd_minor_t record
 * @name: the device file name
 *
 * Registers an ALSA device file for the given card.
 * The operators have to be set in reg parameter.
 *
 * Retrurns zero if successful, or a negative error code on failure.
 */
int snd_register_device(int type, snd_card_t * card, int dev, snd_minor_t * reg, const char *name)
{
	int minor = snd_kernel_minor(type, card, dev);
	snd_minor_t *preg;
	struct device *device = NULL;

	if (minor < 0)
		return minor;
	snd_assert(name, return -EINVAL);
	preg = (snd_minor_t *)kmalloc(sizeof(snd_minor_t) + strlen(name) + 1, GFP_KERNEL);
	if (preg == NULL)
		return -ENOMEM;
	*preg = *reg;
	preg->number = minor;
	preg->device = dev;
	strcpy(preg->name, name);
	down(&sound_mutex);
	if (snd_minor_search(minor)) {
		up(&sound_mutex);
		kfree(preg);
		return -EBUSY;
	}
	list_add_tail(&preg->list, &snd_minors_hash[SNDRV_MINOR_CARD(minor)]);
	if (strncmp(name, "controlC", 8) || card->number >= cards_limit)
		devfs_mk_cdev(MKDEV(major, minor), S_IFCHR | device_mode, "snd/%s", name);
	if (card)
		device = card->dev;
	class_device_create(sound_class, NULL, MKDEV(major, minor), device, "%s", name);

	up(&sound_mutex);
	return 0;
}

/**
 * snd_unregister_device - unregister the device on the given card
 * @type: the device type, SNDRV_DEVICE_TYPE_XXX
 * @card: the card instance
 * @dev: the device index
 *
 * Unregisters the device file already registered via
 * snd_register_device().
 *
 * Returns zero if sucecessful, or a negative error code on failure
 */
int snd_unregister_device(int type, snd_card_t * card, int dev)
{
	int minor = snd_kernel_minor(type, card, dev);
	snd_minor_t *mptr;

	if (minor < 0)
		return minor;
	down(&sound_mutex);
	if ((mptr = snd_minor_search(minor)) == NULL) {
		up(&sound_mutex);
		return -EINVAL;
	}

	if (strncmp(mptr->name, "controlC", 8) || card->number >= cards_limit) /* created in sound.c */
		devfs_remove("snd/%s", mptr->name);
	class_device_destroy(sound_class, MKDEV(major, minor));

	list_del(&mptr->list);
	up(&sound_mutex);
	kfree(mptr);
	return 0;
}

/*
 *  INFO PART
 */

static snd_info_entry_t *snd_minor_info_entry = NULL;

static void snd_minor_info_read(snd_info_entry_t *entry, snd_info_buffer_t * buffer)
{
	int card, device;
	struct list_head *list;
	snd_minor_t *mptr;

	down(&sound_mutex);
	for (card = 0; card < SNDRV_CARDS; card++) {
		list_for_each(list, &snd_minors_hash[card]) {
			mptr = list_entry(list, snd_minor_t, list);
			if (SNDRV_MINOR_DEVICE(mptr->number) != SNDRV_MINOR_SEQUENCER) {
				if ((device = mptr->device) >= 0)
					snd_iprintf(buffer, "%3i: [%i-%2i]: %s\n", mptr->number, card, device, mptr->comment);
				else
					snd_iprintf(buffer, "%3i: [%i]   : %s\n", mptr->number, card, mptr->comment);
			} else {
				snd_iprintf(buffer, "%3i:       : %s\n", mptr->number, mptr->comment);
			}
		}
	}
	up(&sound_mutex);
}

int __init snd_minor_info_init(void)
{
	snd_info_entry_t *entry;

	entry = snd_info_create_module_entry(THIS_MODULE, "devices", NULL);
	if (entry) {
		entry->c.text.read_size = PAGE_SIZE;
		entry->c.text.read = snd_minor_info_read;
		if (snd_info_register(entry) < 0) {
			snd_info_free_entry(entry);
			entry = NULL;
		}
	}
	snd_minor_info_entry = entry;
	return 0;
}

int __exit snd_minor_info_done(void)
{
	if (snd_minor_info_entry)
		snd_info_unregister(snd_minor_info_entry);
	return 0;
}

/*
 *  INIT PART
 */

#ifdef CONFIG_SND_GENERIC_DRIVER
extern struct device_driver snd_generic_driver;
#endif

static int __init alsa_sound_init(void)
{
	short controlnum;
	int err;
	int card;

	snd_major = major;
	snd_ecards_limit = cards_limit;
	for (card = 0; card < SNDRV_CARDS; card++)
		INIT_LIST_HEAD(&snd_minors_hash[card]);
	if ((err = snd_oss_init_module()) < 0)
		return err;
	devfs_mk_dir("snd");
	if (register_chrdev(major, "alsa", &snd_fops)) {
		snd_printk(KERN_ERR "unable to register native major device number %d\n", major);
		devfs_remove("snd");
		return -EIO;
	}
	if (snd_info_init() < 0) {
		unregister_chrdev(major, "alsa");
		devfs_remove("snd");
		return -ENOMEM;
	}
	snd_info_minor_register();
#ifdef CONFIG_SND_GENERIC_DRIVER
	driver_register(&snd_generic_driver);
#endif
	for (controlnum = 0; controlnum < cards_limit; controlnum++)
		devfs_mk_cdev(MKDEV(major, controlnum<<5), S_IFCHR | device_mode, "snd/controlC%d", controlnum);
#ifndef MODULE
	printk(KERN_INFO "Advanced Linux Sound Architecture Driver Version " CONFIG_SND_VERSION CONFIG_SND_DATE ".\n");
#endif
	return 0;
}

static void __exit alsa_sound_exit(void)
{
	short controlnum;

	for (controlnum = 0; controlnum < cards_limit; controlnum++)
		devfs_remove("snd/controlC%d", controlnum);

#ifdef CONFIG_SND_GENERIC_DRIVER
	driver_unregister(&snd_generic_driver);
#endif
	snd_info_minor_unregister();
	snd_info_done();
	if (unregister_chrdev(major, "alsa") != 0)
		snd_printk(KERN_ERR "unable to unregister major device number %d\n", major);
	devfs_remove("snd");
}

module_init(alsa_sound_init)
module_exit(alsa_sound_exit)

  /* sound.c */
EXPORT_SYMBOL(snd_major);
EXPORT_SYMBOL(snd_ecards_limit);
#if defined(CONFIG_KMOD)
EXPORT_SYMBOL(snd_request_card);
#endif
EXPORT_SYMBOL(snd_register_device);
EXPORT_SYMBOL(snd_unregister_device);
#if defined(CONFIG_SND_OSSEMUL)
EXPORT_SYMBOL(snd_register_oss_device);
EXPORT_SYMBOL(snd_unregister_oss_device);
#endif
  /* memory.c */
EXPORT_SYMBOL(copy_to_user_fromio);
EXPORT_SYMBOL(copy_from_user_toio);
  /* init.c */
EXPORT_SYMBOL(snd_cards);
#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
EXPORT_SYMBOL(snd_mixer_oss_notify_callback);
#endif
EXPORT_SYMBOL(snd_card_new);
EXPORT_SYMBOL(snd_card_disconnect);
EXPORT_SYMBOL(snd_card_free);
EXPORT_SYMBOL(snd_card_free_in_thread);
EXPORT_SYMBOL(snd_card_register);
EXPORT_SYMBOL(snd_component_add);
EXPORT_SYMBOL(snd_card_file_add);
EXPORT_SYMBOL(snd_card_file_remove);
#ifdef CONFIG_SND_GENERIC_DRIVER
EXPORT_SYMBOL(snd_card_set_generic_dev);
#endif
#ifdef CONFIG_PM
EXPORT_SYMBOL(snd_power_wait);
EXPORT_SYMBOL(snd_card_set_pm_callback);
#ifdef CONFIG_SND_GENERIC_DRIVER
EXPORT_SYMBOL(snd_card_set_generic_pm_callback);
#endif
#ifdef CONFIG_PCI
EXPORT_SYMBOL(snd_card_pci_suspend);
EXPORT_SYMBOL(snd_card_pci_resume);
#endif
#endif
  /* device.c */
EXPORT_SYMBOL(snd_device_new);
EXPORT_SYMBOL(snd_device_register);
EXPORT_SYMBOL(snd_device_free);
  /* isadma.c */
#ifdef CONFIG_ISA_DMA_API
EXPORT_SYMBOL(snd_dma_program);
EXPORT_SYMBOL(snd_dma_disable);
EXPORT_SYMBOL(snd_dma_pointer);
#endif
  /* info.c */
#ifdef CONFIG_PROC_FS
EXPORT_SYMBOL(snd_seq_root);
EXPORT_SYMBOL(snd_iprintf);
EXPORT_SYMBOL(snd_info_get_line);
EXPORT_SYMBOL(snd_info_get_str);
EXPORT_SYMBOL(snd_info_create_module_entry);
EXPORT_SYMBOL(snd_info_create_card_entry);
EXPORT_SYMBOL(snd_info_free_entry);
EXPORT_SYMBOL(snd_info_register);
EXPORT_SYMBOL(snd_info_unregister);
EXPORT_SYMBOL(snd_card_proc_new);
#endif
  /* info_oss.c */
#if defined(CONFIG_SND_OSSEMUL) && defined(CONFIG_PROC_FS)
EXPORT_SYMBOL(snd_oss_info_register);
#endif
  /* control.c */
EXPORT_SYMBOL(snd_ctl_new);
EXPORT_SYMBOL(snd_ctl_new1);
EXPORT_SYMBOL(snd_ctl_free_one);
EXPORT_SYMBOL(snd_ctl_add);
EXPORT_SYMBOL(snd_ctl_remove);
EXPORT_SYMBOL(snd_ctl_remove_id);
EXPORT_SYMBOL(snd_ctl_rename_id);
EXPORT_SYMBOL(snd_ctl_find_numid);
EXPORT_SYMBOL(snd_ctl_find_id);
EXPORT_SYMBOL(snd_ctl_notify);
EXPORT_SYMBOL(snd_ctl_register_ioctl);
EXPORT_SYMBOL(snd_ctl_unregister_ioctl);
#ifdef CONFIG_COMPAT
EXPORT_SYMBOL(snd_ctl_register_ioctl_compat);
EXPORT_SYMBOL(snd_ctl_unregister_ioctl_compat);
#endif
EXPORT_SYMBOL(snd_ctl_elem_read);
EXPORT_SYMBOL(snd_ctl_elem_write);
  /* misc.c */
EXPORT_SYMBOL(release_and_free_resource);
#ifdef CONFIG_SND_VERBOSE_PRINTK
EXPORT_SYMBOL(snd_verbose_printk);
#endif
#if defined(CONFIG_SND_DEBUG) && defined(CONFIG_SND_VERBOSE_PRINTK)
EXPORT_SYMBOL(snd_verbose_printd);
#endif