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CommitLineData
1da177e4
LT
1/*
2 * Advanced Linux Sound Architecture
3 * Copyright (c) by Jaroslav Kysela <perex@suse.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/init.h>
24#include <linux/slab.h>
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
LT
36
37#define SNDRV_OS_MINORS 256
38
39static int major = CONFIG_SND_MAJOR;
40int snd_major;
c0d3fb39
TI
41EXPORT_SYMBOL(snd_major);
42
1da177e4 43static int cards_limit = 1;
1da177e4
LT
44
45MODULE_AUTHOR("Jaroslav Kysela <perex@suse.cz>");
46MODULE_DESCRIPTION("Advanced Linux Sound Architecture driver for soundcards.");
47MODULE_LICENSE("GPL");
48module_param(major, int, 0444);
49MODULE_PARM_DESC(major, "Major # for sound driver.");
50module_param(cards_limit, int, 0444);
51MODULE_PARM_DESC(cards_limit, "Count of auto-loadable soundcards.");
1da177e4
LT
52MODULE_ALIAS_CHARDEV_MAJOR(CONFIG_SND_MAJOR);
53
54/* this one holds the actual max. card number currently available.
55 * as default, it's identical with cards_limit option. when more
56 * modules are loaded manually, this limit number increases, too.
57 */
58int snd_ecards_limit;
c0d3fb39 59EXPORT_SYMBOL(snd_ecards_limit);
1da177e4 60
6983b724 61static struct snd_minor *snd_minors[SNDRV_OS_MINORS];
1a60d4c5 62static DEFINE_MUTEX(sound_mutex);
1da177e4 63
619e666b 64extern struct class *sound_class;
1da177e4
LT
65
66
67#ifdef CONFIG_KMOD
68
69/**
70 * snd_request_card - try to load the card module
71 * @card: the card number
72 *
73 * Tries to load the module "snd-card-X" for the given card number
74 * via KMOD. Returns immediately if already loaded.
75 */
76void snd_request_card(int card)
77{
1da177e4
LT
78 if (! current->fs->root)
79 return;
746df948 80 if (snd_card_locked(card))
1da177e4
LT
81 return;
82 if (card < 0 || card >= cards_limit)
83 return;
84 request_module("snd-card-%i", card);
85}
86
c0d3fb39
TI
87EXPORT_SYMBOL(snd_request_card);
88
1da177e4
LT
89static void snd_request_other(int minor)
90{
91 char *str;
92
93 if (! current->fs->root)
94 return;
95 switch (minor) {
96 case SNDRV_MINOR_SEQUENCER: str = "snd-seq"; break;
97 case SNDRV_MINOR_TIMER: str = "snd-timer"; break;
98 default: return;
99 }
100 request_module(str);
101}
102
103#endif /* request_module support */
104
f87135f5
CL
105/**
106 * snd_lookup_minor_data - get user data of a registered device
107 * @minor: the minor number
108 * @type: device type (SNDRV_DEVICE_TYPE_XXX)
109 *
110 * Checks that a minor device with the specified type is registered, and returns
111 * its user data pointer.
112 */
113void *snd_lookup_minor_data(unsigned int minor, int type)
114{
115 struct snd_minor *mreg;
116 void *private_data;
117
3a63e444 118 if (minor >= ARRAY_SIZE(snd_minors))
f87135f5 119 return NULL;
1a60d4c5 120 mutex_lock(&sound_mutex);
f87135f5
CL
121 mreg = snd_minors[minor];
122 if (mreg && mreg->type == type)
123 private_data = mreg->private_data;
124 else
125 private_data = NULL;
1a60d4c5 126 mutex_unlock(&sound_mutex);
f87135f5
CL
127 return private_data;
128}
129
c0d3fb39
TI
130EXPORT_SYMBOL(snd_lookup_minor_data);
131
1da177e4
LT
132static int snd_open(struct inode *inode, struct file *file)
133{
332682b1 134 unsigned int minor = iminor(inode);
512bbd6a 135 struct snd_minor *mptr = NULL;
99ac48f5 136 const struct file_operations *old_fops;
1da177e4
LT
137 int err = 0;
138
3a63e444 139 if (minor >= ARRAY_SIZE(snd_minors))
332682b1
CL
140 return -ENODEV;
141 mptr = snd_minors[minor];
142 if (mptr == NULL) {
1da177e4 143#ifdef CONFIG_KMOD
332682b1
CL
144 int dev = SNDRV_MINOR_DEVICE(minor);
145 if (dev == SNDRV_MINOR_CONTROL) {
146 /* /dev/aloadC? */
147 int card = SNDRV_MINOR_CARD(minor);
1da177e4 148 if (snd_cards[card] == NULL)
332682b1
CL
149 snd_request_card(card);
150 } else if (dev == SNDRV_MINOR_GLOBAL) {
151 /* /dev/aloadSEQ */
1da177e4 152 snd_request_other(minor);
332682b1
CL
153 }
154#ifndef CONFIG_SND_DYNAMIC_MINORS
155 /* /dev/snd/{controlC?,seq} */
156 mptr = snd_minors[minor];
157 if (mptr == NULL)
158#endif
1da177e4 159#endif
332682b1 160 return -ENODEV;
1da177e4 161 }
1da177e4
LT
162 old_fops = file->f_op;
163 file->f_op = fops_get(mptr->f_ops);
164 if (file->f_op->open)
165 err = file->f_op->open(inode, file);
166 if (err) {
167 fops_put(file->f_op);
168 file->f_op = fops_get(old_fops);
169 }
170 fops_put(old_fops);
171 return err;
172}
173
174static struct file_operations snd_fops =
175{
176 .owner = THIS_MODULE,
177 .open = snd_open
178};
179
332682b1
CL
180#ifdef CONFIG_SND_DYNAMIC_MINORS
181static int snd_find_free_minor(void)
182{
183 int minor;
184
185 for (minor = 0; minor < ARRAY_SIZE(snd_minors); ++minor) {
186 /* skip minors still used statically for autoloading devices */
187 if (SNDRV_MINOR_DEVICE(minor) == SNDRV_MINOR_CONTROL ||
188 minor == SNDRV_MINOR_SEQUENCER)
189 continue;
190 if (!snd_minors[minor])
191 return minor;
192 }
193 return -EBUSY;
194}
195#else
512bbd6a 196static int snd_kernel_minor(int type, struct snd_card *card, int dev)
1da177e4
LT
197{
198 int minor;
199
200 switch (type) {
201 case SNDRV_DEVICE_TYPE_SEQUENCER:
202 case SNDRV_DEVICE_TYPE_TIMER:
203 minor = type;
204 break;
205 case SNDRV_DEVICE_TYPE_CONTROL:
206 snd_assert(card != NULL, return -EINVAL);
207 minor = SNDRV_MINOR(card->number, type);
208 break;
209 case SNDRV_DEVICE_TYPE_HWDEP:
210 case SNDRV_DEVICE_TYPE_RAWMIDI:
211 case SNDRV_DEVICE_TYPE_PCM_PLAYBACK:
212 case SNDRV_DEVICE_TYPE_PCM_CAPTURE:
213 snd_assert(card != NULL, return -EINVAL);
214 minor = SNDRV_MINOR(card->number, type + dev);
215 break;
216 default:
217 return -EINVAL;
218 }
219 snd_assert(minor >= 0 && minor < SNDRV_OS_MINORS, return -EINVAL);
220 return minor;
221}
332682b1 222#endif
1da177e4
LT
223
224/**
225 * snd_register_device - Register the ALSA device file for the card
226 * @type: the device type, SNDRV_DEVICE_TYPE_XXX
227 * @card: the card instance
228 * @dev: the device index
2af677fc 229 * @f_ops: the file operations
f87135f5 230 * @private_data: user pointer for f_ops->open()
1da177e4
LT
231 * @name: the device file name
232 *
233 * Registers an ALSA device file for the given card.
234 * The operators have to be set in reg parameter.
235 *
236 * Retrurns zero if successful, or a negative error code on failure.
237 */
2af677fc 238int snd_register_device(int type, struct snd_card *card, int dev,
99ac48f5 239 const struct file_operations *f_ops, void *private_data,
f87135f5 240 const char *name)
1da177e4 241{
332682b1 242 int minor;
512bbd6a 243 struct snd_minor *preg;
1da177e4
LT
244 struct device *device = NULL;
245
1da177e4 246 snd_assert(name, return -EINVAL);
6983b724 247 preg = kmalloc(sizeof(struct snd_minor) + strlen(name) + 1, GFP_KERNEL);
1da177e4
LT
248 if (preg == NULL)
249 return -ENOMEM;
2af677fc 250 preg->type = type;
6983b724 251 preg->card = card ? card->number : -1;
1da177e4 252 preg->device = dev;
2af677fc 253 preg->f_ops = f_ops;
f87135f5 254 preg->private_data = private_data;
1da177e4 255 strcpy(preg->name, name);
1a60d4c5 256 mutex_lock(&sound_mutex);
332682b1
CL
257#ifdef CONFIG_SND_DYNAMIC_MINORS
258 minor = snd_find_free_minor();
259#else
260 minor = snd_kernel_minor(type, card, dev);
261 if (minor >= 0 && snd_minors[minor])
262 minor = -EBUSY;
263#endif
264 if (minor < 0) {
1a60d4c5 265 mutex_unlock(&sound_mutex);
1da177e4 266 kfree(preg);
332682b1 267 return minor;
1da177e4 268 }
6983b724 269 snd_minors[minor] = preg;
3e23c658 270 if (card)
1da177e4 271 device = card->dev;
3e23c658 272 class_device_create(sound_class, NULL, MKDEV(major, minor), device, "%s", name);
1da177e4 273
1a60d4c5 274 mutex_unlock(&sound_mutex);
1da177e4
LT
275 return 0;
276}
277
c0d3fb39
TI
278EXPORT_SYMBOL(snd_register_device);
279
1da177e4
LT
280/**
281 * snd_unregister_device - unregister the device on the given card
282 * @type: the device type, SNDRV_DEVICE_TYPE_XXX
283 * @card: the card instance
284 * @dev: the device index
285 *
286 * Unregisters the device file already registered via
287 * snd_register_device().
288 *
289 * Returns zero if sucecessful, or a negative error code on failure
290 */
512bbd6a 291int snd_unregister_device(int type, struct snd_card *card, int dev)
1da177e4 292{
f87135f5 293 int cardnum, minor;
512bbd6a 294 struct snd_minor *mptr;
1da177e4 295
f87135f5 296 cardnum = card ? card->number : -1;
1a60d4c5 297 mutex_lock(&sound_mutex);
f87135f5
CL
298 for (minor = 0; minor < ARRAY_SIZE(snd_minors); ++minor)
299 if ((mptr = snd_minors[minor]) != NULL &&
300 mptr->type == type &&
301 mptr->card == cardnum &&
302 mptr->device == dev)
303 break;
304 if (minor == ARRAY_SIZE(snd_minors)) {
1a60d4c5 305 mutex_unlock(&sound_mutex);
1da177e4
LT
306 return -EINVAL;
307 }
308
619e666b 309 class_device_destroy(sound_class, MKDEV(major, minor));
1da177e4 310
6983b724 311 snd_minors[minor] = NULL;
1a60d4c5 312 mutex_unlock(&sound_mutex);
1da177e4
LT
313 kfree(mptr);
314 return 0;
315}
316
c0d3fb39
TI
317EXPORT_SYMBOL(snd_unregister_device);
318
e28563cc 319#ifdef CONFIG_PROC_FS
1da177e4
LT
320/*
321 * INFO PART
322 */
323
6581f4e7 324static struct snd_info_entry *snd_minor_info_entry;
1da177e4 325
2af677fc
CL
326static const char *snd_device_type_name(int type)
327{
328 switch (type) {
329 case SNDRV_DEVICE_TYPE_CONTROL:
330 return "control";
331 case SNDRV_DEVICE_TYPE_HWDEP:
332 return "hardware dependent";
333 case SNDRV_DEVICE_TYPE_RAWMIDI:
334 return "raw midi";
335 case SNDRV_DEVICE_TYPE_PCM_PLAYBACK:
336 return "digital audio playback";
337 case SNDRV_DEVICE_TYPE_PCM_CAPTURE:
338 return "digital audio capture";
339 case SNDRV_DEVICE_TYPE_SEQUENCER:
340 return "sequencer";
341 case SNDRV_DEVICE_TYPE_TIMER:
342 return "timer";
343 default:
344 return "?";
345 }
346}
347
512bbd6a 348static void snd_minor_info_read(struct snd_info_entry *entry, struct snd_info_buffer *buffer)
1da177e4 349{
6983b724 350 int minor;
512bbd6a 351 struct snd_minor *mptr;
1da177e4 352
1a60d4c5 353 mutex_lock(&sound_mutex);
6983b724
CL
354 for (minor = 0; minor < SNDRV_OS_MINORS; ++minor) {
355 if (!(mptr = snd_minors[minor]))
356 continue;
357 if (mptr->card >= 0) {
358 if (mptr->device >= 0)
d001544d 359 snd_iprintf(buffer, "%3i: [%2i-%2i]: %s\n",
6983b724
CL
360 minor, mptr->card, mptr->device,
361 snd_device_type_name(mptr->type));
362 else
d001544d 363 snd_iprintf(buffer, "%3i: [%2i] : %s\n",
6983b724
CL
364 minor, mptr->card,
365 snd_device_type_name(mptr->type));
366 } else
d001544d 367 snd_iprintf(buffer, "%3i: : %s\n", minor,
6983b724 368 snd_device_type_name(mptr->type));
1da177e4 369 }
1a60d4c5 370 mutex_unlock(&sound_mutex);
1da177e4
LT
371}
372
373int __init snd_minor_info_init(void)
374{
512bbd6a 375 struct snd_info_entry *entry;
1da177e4
LT
376
377 entry = snd_info_create_module_entry(THIS_MODULE, "devices", NULL);
378 if (entry) {
1da177e4
LT
379 entry->c.text.read = snd_minor_info_read;
380 if (snd_info_register(entry) < 0) {
381 snd_info_free_entry(entry);
382 entry = NULL;
383 }
384 }
385 snd_minor_info_entry = entry;
386 return 0;
387}
388
389int __exit snd_minor_info_done(void)
390{
391 if (snd_minor_info_entry)
392 snd_info_unregister(snd_minor_info_entry);
393 return 0;
394}
e28563cc 395#endif /* CONFIG_PROC_FS */
1da177e4
LT
396
397/*
398 * INIT PART
399 */
400
401static int __init alsa_sound_init(void)
402{
1da177e4
LT
403 snd_major = major;
404 snd_ecards_limit = cards_limit;
1da177e4
LT
405 if (register_chrdev(major, "alsa", &snd_fops)) {
406 snd_printk(KERN_ERR "unable to register native major device number %d\n", major);
1da177e4
LT
407 return -EIO;
408 }
1da177e4 409 if (snd_info_init() < 0) {
1da177e4 410 unregister_chrdev(major, "alsa");
1da177e4
LT
411 return -ENOMEM;
412 }
413 snd_info_minor_register();
1da177e4
LT
414#ifndef MODULE
415 printk(KERN_INFO "Advanced Linux Sound Architecture Driver Version " CONFIG_SND_VERSION CONFIG_SND_DATE ".\n");
416#endif
417 return 0;
418}
419
420static void __exit alsa_sound_exit(void)
421{
1da177e4
LT
422 snd_info_minor_unregister();
423 snd_info_done();
1da177e4
LT
424 if (unregister_chrdev(major, "alsa") != 0)
425 snd_printk(KERN_ERR "unable to unregister major device number %d\n", major);
1da177e4
LT
426}
427
428module_init(alsa_sound_init)
429module_exit(alsa_sound_exit)