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22#include <sound/driver.h>
23#include <linux/init.h>
24#include <linux/slab.h>
25#include <linux/time.h>
26#include <linux/device.h>
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>
35#include <linux/mutex.h>
36
37#define SNDRV_OS_MINORS 256
38
39static int major = CONFIG_SND_MAJOR;
40int snd_major;
41EXPORT_SYMBOL(snd_major);
42
43static int cards_limit = 1;
44
45MODULE_AUTHOR("Jaroslav Kysela <perex@perex.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.");
52MODULE_ALIAS_CHARDEV_MAJOR(CONFIG_SND_MAJOR);
53
54
55
56
57
58int snd_ecards_limit;
59EXPORT_SYMBOL(snd_ecards_limit);
60
61static struct snd_minor *snd_minors[SNDRV_OS_MINORS];
62static DEFINE_MUTEX(sound_mutex);
63
64#ifdef CONFIG_KMOD
65
66
67
68
69
70
71
72
73void snd_request_card(int card)
74{
75 if (! current->fs->root)
76 return;
77 if (snd_card_locked(card))
78 return;
79 if (card < 0 || card >= cards_limit)
80 return;
81 request_module("snd-card-%i", card);
82}
83
84EXPORT_SYMBOL(snd_request_card);
85
86static void snd_request_other(int minor)
87{
88 char *str;
89
90 if (! current->fs->root)
91 return;
92 switch (minor) {
93 case SNDRV_MINOR_SEQUENCER: str = "snd-seq"; break;
94 case SNDRV_MINOR_TIMER: str = "snd-timer"; break;
95 default: return;
96 }
97 request_module(str);
98}
99
100#endif
101
102
103
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107
108
109
110void *snd_lookup_minor_data(unsigned int minor, int type)
111{
112 struct snd_minor *mreg;
113 void *private_data;
114
115 if (minor >= ARRAY_SIZE(snd_minors))
116 return NULL;
117 mutex_lock(&sound_mutex);
118 mreg = snd_minors[minor];
119 if (mreg && mreg->type == type)
120 private_data = mreg->private_data;
121 else
122 private_data = NULL;
123 mutex_unlock(&sound_mutex);
124 return private_data;
125}
126
127EXPORT_SYMBOL(snd_lookup_minor_data);
128
129static int snd_open(struct inode *inode, struct file *file)
130{
131 unsigned int minor = iminor(inode);
132 struct snd_minor *mptr = NULL;
133 const struct file_operations *old_fops;
134 int err = 0;
135
136 if (minor >= ARRAY_SIZE(snd_minors))
137 return -ENODEV;
138 mptr = snd_minors[minor];
139 if (mptr == NULL) {
140#ifdef CONFIG_KMOD
141 int dev = SNDRV_MINOR_DEVICE(minor);
142 if (dev == SNDRV_MINOR_CONTROL) {
143
144 int card = SNDRV_MINOR_CARD(minor);
145 if (snd_cards[card] == NULL)
146 snd_request_card(card);
147 } else if (dev == SNDRV_MINOR_GLOBAL) {
148
149 snd_request_other(minor);
150 }
151#ifndef CONFIG_SND_DYNAMIC_MINORS
152
153 mptr = snd_minors[minor];
154 if (mptr == NULL)
155#endif
156#endif
157 return -ENODEV;
158 }
159 old_fops = file->f_op;
160 file->f_op = fops_get(mptr->f_ops);
161 if (file->f_op->open)
162 err = file->f_op->open(inode, file);
163 if (err) {
164 fops_put(file->f_op);
165 file->f_op = fops_get(old_fops);
166 }
167 fops_put(old_fops);
168 return err;
169}
170
171static const struct file_operations snd_fops =
172{
173 .owner = THIS_MODULE,
174 .open = snd_open
175};
176
177#ifdef CONFIG_SND_DYNAMIC_MINORS
178static int snd_find_free_minor(void)
179{
180 int minor;
181
182 for (minor = 0; minor < ARRAY_SIZE(snd_minors); ++minor) {
183
184 if (SNDRV_MINOR_DEVICE(minor) == SNDRV_MINOR_CONTROL ||
185 minor == SNDRV_MINOR_SEQUENCER)
186 continue;
187 if (!snd_minors[minor])
188 return minor;
189 }
190 return -EBUSY;
191}
192#else
193static int snd_kernel_minor(int type, struct snd_card *card, int dev)
194{
195 int minor;
196
197 switch (type) {
198 case SNDRV_DEVICE_TYPE_SEQUENCER:
199 case SNDRV_DEVICE_TYPE_TIMER:
200 minor = type;
201 break;
202 case SNDRV_DEVICE_TYPE_CONTROL:
203 snd_assert(card != NULL, return -EINVAL);
204 minor = SNDRV_MINOR(card->number, type);
205 break;
206 case SNDRV_DEVICE_TYPE_HWDEP:
207 case SNDRV_DEVICE_TYPE_RAWMIDI:
208 case SNDRV_DEVICE_TYPE_PCM_PLAYBACK:
209 case SNDRV_DEVICE_TYPE_PCM_CAPTURE:
210 snd_assert(card != NULL, return -EINVAL);
211 minor = SNDRV_MINOR(card->number, type + dev);
212 break;
213 default:
214 return -EINVAL;
215 }
216 snd_assert(minor >= 0 && minor < SNDRV_OS_MINORS, return -EINVAL);
217 return minor;
218}
219#endif
220
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234
235
236int snd_register_device_for_dev(int type, struct snd_card *card, int dev,
237 const struct file_operations *f_ops,
238 void *private_data,
239 const char *name, struct device *device)
240{
241 int minor;
242 struct snd_minor *preg;
243
244 snd_assert(name, return -EINVAL);
245 preg = kmalloc(sizeof *preg, GFP_KERNEL);
246 if (preg == NULL)
247 return -ENOMEM;
248 preg->type = type;
249 preg->card = card ? card->number : -1;
250 preg->device = dev;
251 preg->f_ops = f_ops;
252 preg->private_data = private_data;
253 mutex_lock(&sound_mutex);
254#ifdef CONFIG_SND_DYNAMIC_MINORS
255 minor = snd_find_free_minor();
256#else
257 minor = snd_kernel_minor(type, card, dev);
258 if (minor >= 0 && snd_minors[minor])
259 minor = -EBUSY;
260#endif
261 if (minor < 0) {
262 mutex_unlock(&sound_mutex);
263 kfree(preg);
264 return minor;
265 }
266 snd_minors[minor] = preg;
267 preg->dev = device_create(sound_class, device, MKDEV(major, minor),
268 "%s", name);
269 if (IS_ERR(preg->dev)) {
270 snd_minors[minor] = NULL;
271 mutex_unlock(&sound_mutex);
272 minor = PTR_ERR(preg->dev);
273 kfree(preg);
274 return minor;
275 }
276
277 if (preg->dev)
278 dev_set_drvdata(preg->dev, private_data);
279
280 mutex_unlock(&sound_mutex);
281 return 0;
282}
283
284EXPORT_SYMBOL(snd_register_device_for_dev);
285
286
287
288
289static int find_snd_minor(int type, struct snd_card *card, int dev)
290{
291 int cardnum, minor;
292 struct snd_minor *mptr;
293
294 cardnum = card ? card->number : -1;
295 for (minor = 0; minor < ARRAY_SIZE(snd_minors); ++minor)
296 if ((mptr = snd_minors[minor]) != NULL &&
297 mptr->type == type &&
298 mptr->card == cardnum &&
299 mptr->device == dev)
300 return minor;
301 return -1;
302}
303
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311
312
313
314
315int snd_unregister_device(int type, struct snd_card *card, int dev)
316{
317 int minor;
318
319 mutex_lock(&sound_mutex);
320 minor = find_snd_minor(type, card, dev);
321 if (minor < 0) {
322 mutex_unlock(&sound_mutex);
323 return -EINVAL;
324 }
325
326 device_destroy(sound_class, MKDEV(major, minor));
327
328 kfree(snd_minors[minor]);
329 snd_minors[minor] = NULL;
330 mutex_unlock(&sound_mutex);
331 return 0;
332}
333
334EXPORT_SYMBOL(snd_unregister_device);
335
336int snd_add_device_sysfs_file(int type, struct snd_card *card, int dev,
337 struct device_attribute *attr)
338{
339 int minor, ret = -EINVAL;
340 struct device *d;
341
342 mutex_lock(&sound_mutex);
343 minor = find_snd_minor(type, card, dev);
344 if (minor >= 0 && (d = snd_minors[minor]->dev) != NULL)
345 ret = device_create_file(d, attr);
346 mutex_unlock(&sound_mutex);
347 return ret;
348
349}
350
351EXPORT_SYMBOL(snd_add_device_sysfs_file);
352
353#ifdef CONFIG_PROC_FS
354
355
356
357
358static struct snd_info_entry *snd_minor_info_entry;
359
360static const char *snd_device_type_name(int type)
361{
362 switch (type) {
363 case SNDRV_DEVICE_TYPE_CONTROL:
364 return "control";
365 case SNDRV_DEVICE_TYPE_HWDEP:
366 return "hardware dependent";
367 case SNDRV_DEVICE_TYPE_RAWMIDI:
368 return "raw midi";
369 case SNDRV_DEVICE_TYPE_PCM_PLAYBACK:
370 return "digital audio playback";
371 case SNDRV_DEVICE_TYPE_PCM_CAPTURE:
372 return "digital audio capture";
373 case SNDRV_DEVICE_TYPE_SEQUENCER:
374 return "sequencer";
375 case SNDRV_DEVICE_TYPE_TIMER:
376 return "timer";
377 default:
378 return "?";
379 }
380}
381
382static void snd_minor_info_read(struct snd_info_entry *entry, struct snd_info_buffer *buffer)
383{
384 int minor;
385 struct snd_minor *mptr;
386
387 mutex_lock(&sound_mutex);
388 for (minor = 0; minor < SNDRV_OS_MINORS; ++minor) {
389 if (!(mptr = snd_minors[minor]))
390 continue;
391 if (mptr->card >= 0) {
392 if (mptr->device >= 0)
393 snd_iprintf(buffer, "%3i: [%2i-%2i]: %s\n",
394 minor, mptr->card, mptr->device,
395 snd_device_type_name(mptr->type));
396 else
397 snd_iprintf(buffer, "%3i: [%2i] : %s\n",
398 minor, mptr->card,
399 snd_device_type_name(mptr->type));
400 } else
401 snd_iprintf(buffer, "%3i: : %s\n", minor,
402 snd_device_type_name(mptr->type));
403 }
404 mutex_unlock(&sound_mutex);
405}
406
407int __init snd_minor_info_init(void)
408{
409 struct snd_info_entry *entry;
410
411 entry = snd_info_create_module_entry(THIS_MODULE, "devices", NULL);
412 if (entry) {
413 entry->c.text.read = snd_minor_info_read;
414 if (snd_info_register(entry) < 0) {
415 snd_info_free_entry(entry);
416 entry = NULL;
417 }
418 }
419 snd_minor_info_entry = entry;
420 return 0;
421}
422
423int __exit snd_minor_info_done(void)
424{
425 snd_info_free_entry(snd_minor_info_entry);
426 return 0;
427}
428#endif
429
430
431
432
433
434static int __init alsa_sound_init(void)
435{
436 snd_major = major;
437 snd_ecards_limit = cards_limit;
438 if (register_chrdev(major, "alsa", &snd_fops)) {
439 snd_printk(KERN_ERR "unable to register native major device number %d\n", major);
440 return -EIO;
441 }
442 if (snd_info_init() < 0) {
443 unregister_chrdev(major, "alsa");
444 return -ENOMEM;
445 }
446 snd_info_minor_register();
447#ifndef MODULE
448 printk(KERN_INFO "Advanced Linux Sound Architecture Driver Version " CONFIG_SND_VERSION CONFIG_SND_DATE ".\n");
449#endif
450 return 0;
451}
452
453static void __exit alsa_sound_exit(void)
454{
455 snd_info_minor_unregister();
456 snd_info_done();
457 unregister_chrdev(major, "alsa");
458}
459
460module_init(alsa_sound_init)
461module_exit(alsa_sound_exit)
462