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22#include <linux/init.h>
23#include <linux/slab.h>
24#include <linux/time.h>
25#include <linux/device.h>
26#include <linux/module.h>
27#include <sound/core.h>
28#include <sound/minors.h>
29#include <sound/info.h>
30#include <sound/control.h>
31#include <sound/initval.h>
32#include <linux/kmod.h>
33#include <linux/mutex.h>
34
35static int major = CONFIG_SND_MAJOR;
36int snd_major;
37EXPORT_SYMBOL(snd_major);
38
39static int cards_limit = 1;
40
41MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
42MODULE_DESCRIPTION("Advanced Linux Sound Architecture driver for soundcards.");
43MODULE_LICENSE("GPL");
44module_param(major, int, 0444);
45MODULE_PARM_DESC(major, "Major # for sound driver.");
46module_param(cards_limit, int, 0444);
47MODULE_PARM_DESC(cards_limit, "Count of auto-loadable soundcards.");
48MODULE_ALIAS_CHARDEV_MAJOR(CONFIG_SND_MAJOR);
49
50
51
52
53
54int snd_ecards_limit;
55EXPORT_SYMBOL(snd_ecards_limit);
56
57static struct snd_minor *snd_minors[SNDRV_OS_MINORS];
58static DEFINE_MUTEX(sound_mutex);
59
60#ifdef CONFIG_MODULES
61
62
63
64
65
66
67
68
69void snd_request_card(int card)
70{
71 if (snd_card_locked(card))
72 return;
73 if (card < 0 || card >= cards_limit)
74 return;
75 request_module("snd-card-%i", card);
76}
77
78EXPORT_SYMBOL(snd_request_card);
79
80static void snd_request_other(int minor)
81{
82 char *str;
83
84 switch (minor) {
85 case SNDRV_MINOR_SEQUENCER: str = "snd-seq"; break;
86 case SNDRV_MINOR_TIMER: str = "snd-timer"; break;
87 default: return;
88 }
89 request_module(str);
90}
91
92#endif
93
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107
108
109void *snd_lookup_minor_data(unsigned int minor, int type)
110{
111 struct snd_minor *mreg;
112 void *private_data;
113
114 if (minor >= ARRAY_SIZE(snd_minors))
115 return NULL;
116 mutex_lock(&sound_mutex);
117 mreg = snd_minors[minor];
118 if (mreg && mreg->type == type) {
119 private_data = mreg->private_data;
120 if (private_data && mreg->card_ptr)
121 get_device(&mreg->card_ptr->card_dev);
122 } else
123 private_data = NULL;
124 mutex_unlock(&sound_mutex);
125 return private_data;
126}
127
128EXPORT_SYMBOL(snd_lookup_minor_data);
129
130#ifdef CONFIG_MODULES
131static struct snd_minor *autoload_device(unsigned int minor)
132{
133 int dev;
134 mutex_unlock(&sound_mutex);
135 dev = SNDRV_MINOR_DEVICE(minor);
136 if (dev == SNDRV_MINOR_CONTROL) {
137
138 int card = SNDRV_MINOR_CARD(minor);
139 if (snd_cards[card] == NULL)
140 snd_request_card(card);
141 } else if (dev == SNDRV_MINOR_GLOBAL) {
142
143 snd_request_other(minor);
144 }
145 mutex_lock(&sound_mutex);
146 return snd_minors[minor];
147}
148#else
149#define autoload_device(minor) NULL
150#endif
151
152static int snd_open(struct inode *inode, struct file *file)
153{
154 unsigned int minor = iminor(inode);
155 struct snd_minor *mptr = NULL;
156 const struct file_operations *new_fops;
157 int err = 0;
158
159 if (minor >= ARRAY_SIZE(snd_minors))
160 return -ENODEV;
161 mutex_lock(&sound_mutex);
162 mptr = snd_minors[minor];
163 if (mptr == NULL) {
164 mptr = autoload_device(minor);
165 if (!mptr) {
166 mutex_unlock(&sound_mutex);
167 return -ENODEV;
168 }
169 }
170 new_fops = fops_get(mptr->f_ops);
171 mutex_unlock(&sound_mutex);
172 if (!new_fops)
173 return -ENODEV;
174 replace_fops(file, new_fops);
175
176 if (file->f_op->open)
177 err = file->f_op->open(inode, file);
178 return err;
179}
180
181static const struct file_operations snd_fops =
182{
183 .owner = THIS_MODULE,
184 .open = snd_open,
185 .llseek = noop_llseek,
186};
187
188#ifdef CONFIG_SND_DYNAMIC_MINORS
189static int snd_find_free_minor(int type, struct snd_card *card, int dev)
190{
191 int minor;
192
193
194 if (type == SNDRV_DEVICE_TYPE_SEQUENCER)
195 return SNDRV_MINOR_SEQUENCER;
196 if (type == SNDRV_DEVICE_TYPE_TIMER)
197 return SNDRV_MINOR_TIMER;
198
199 for (minor = 0; minor < ARRAY_SIZE(snd_minors); ++minor) {
200
201 if (SNDRV_MINOR_DEVICE(minor) == SNDRV_MINOR_CONTROL)
202 continue;
203 if (minor == SNDRV_MINOR_SEQUENCER ||
204 minor == SNDRV_MINOR_TIMER)
205 continue;
206 if (!snd_minors[minor])
207 return minor;
208 }
209 return -EBUSY;
210}
211#else
212static int snd_find_free_minor(int type, struct snd_card *card, int dev)
213{
214 int minor;
215
216 switch (type) {
217 case SNDRV_DEVICE_TYPE_SEQUENCER:
218 case SNDRV_DEVICE_TYPE_TIMER:
219 minor = type;
220 break;
221 case SNDRV_DEVICE_TYPE_CONTROL:
222 if (snd_BUG_ON(!card))
223 return -EINVAL;
224 minor = SNDRV_MINOR(card->number, type);
225 break;
226 case SNDRV_DEVICE_TYPE_HWDEP:
227 case SNDRV_DEVICE_TYPE_RAWMIDI:
228 case SNDRV_DEVICE_TYPE_PCM_PLAYBACK:
229 case SNDRV_DEVICE_TYPE_PCM_CAPTURE:
230 case SNDRV_DEVICE_TYPE_COMPRESS:
231 if (snd_BUG_ON(!card))
232 return -EINVAL;
233 minor = SNDRV_MINOR(card->number, type + dev);
234 break;
235 default:
236 return -EINVAL;
237 }
238 if (snd_BUG_ON(minor < 0 || minor >= SNDRV_OS_MINORS))
239 return -EINVAL;
240 if (snd_minors[minor])
241 return -EBUSY;
242 return minor;
243}
244#endif
245
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259
260int snd_register_device(int type, struct snd_card *card, int dev,
261 const struct file_operations *f_ops,
262 void *private_data, struct device *device)
263{
264 int minor;
265 int err = 0;
266 struct snd_minor *preg;
267
268 if (snd_BUG_ON(!device))
269 return -EINVAL;
270
271 preg = kmalloc(sizeof *preg, GFP_KERNEL);
272 if (preg == NULL)
273 return -ENOMEM;
274 preg->type = type;
275 preg->card = card ? card->number : -1;
276 preg->device = dev;
277 preg->f_ops = f_ops;
278 preg->private_data = private_data;
279 preg->card_ptr = card;
280 mutex_lock(&sound_mutex);
281 minor = snd_find_free_minor(type, card, dev);
282 if (minor < 0) {
283 err = minor;
284 goto error;
285 }
286
287 preg->dev = device;
288 device->devt = MKDEV(major, minor);
289 err = device_add(device);
290 if (err < 0)
291 goto error;
292
293 snd_minors[minor] = preg;
294 error:
295 mutex_unlock(&sound_mutex);
296 if (err < 0)
297 kfree(preg);
298 return err;
299}
300EXPORT_SYMBOL(snd_register_device);
301
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307
308
309
310
311int snd_unregister_device(struct device *dev)
312{
313 int minor;
314 struct snd_minor *preg;
315
316 mutex_lock(&sound_mutex);
317 for (minor = 0; minor < ARRAY_SIZE(snd_minors); ++minor) {
318 preg = snd_minors[minor];
319 if (preg && preg->dev == dev) {
320 snd_minors[minor] = NULL;
321 device_del(dev);
322 kfree(preg);
323 break;
324 }
325 }
326 mutex_unlock(&sound_mutex);
327 if (minor >= ARRAY_SIZE(snd_minors))
328 return -ENOENT;
329 return 0;
330}
331EXPORT_SYMBOL(snd_unregister_device);
332
333#ifdef CONFIG_SND_PROC_FS
334
335
336
337static const char *snd_device_type_name(int type)
338{
339 switch (type) {
340 case SNDRV_DEVICE_TYPE_CONTROL:
341 return "control";
342 case SNDRV_DEVICE_TYPE_HWDEP:
343 return "hardware dependent";
344 case SNDRV_DEVICE_TYPE_RAWMIDI:
345 return "raw midi";
346 case SNDRV_DEVICE_TYPE_PCM_PLAYBACK:
347 return "digital audio playback";
348 case SNDRV_DEVICE_TYPE_PCM_CAPTURE:
349 return "digital audio capture";
350 case SNDRV_DEVICE_TYPE_SEQUENCER:
351 return "sequencer";
352 case SNDRV_DEVICE_TYPE_TIMER:
353 return "timer";
354 default:
355 return "?";
356 }
357}
358
359static void snd_minor_info_read(struct snd_info_entry *entry, struct snd_info_buffer *buffer)
360{
361 int minor;
362 struct snd_minor *mptr;
363
364 mutex_lock(&sound_mutex);
365 for (minor = 0; minor < SNDRV_OS_MINORS; ++minor) {
366 if (!(mptr = snd_minors[minor]))
367 continue;
368 if (mptr->card >= 0) {
369 if (mptr->device >= 0)
370 snd_iprintf(buffer, "%3i: [%2i-%2i]: %s\n",
371 minor, mptr->card, mptr->device,
372 snd_device_type_name(mptr->type));
373 else
374 snd_iprintf(buffer, "%3i: [%2i] : %s\n",
375 minor, mptr->card,
376 snd_device_type_name(mptr->type));
377 } else
378 snd_iprintf(buffer, "%3i: : %s\n", minor,
379 snd_device_type_name(mptr->type));
380 }
381 mutex_unlock(&sound_mutex);
382}
383
384int __init snd_minor_info_init(void)
385{
386 struct snd_info_entry *entry;
387
388 entry = snd_info_create_module_entry(THIS_MODULE, "devices", NULL);
389 if (!entry)
390 return -ENOMEM;
391 entry->c.text.read = snd_minor_info_read;
392 return snd_info_register(entry);
393}
394#endif
395
396
397
398
399
400static int __init alsa_sound_init(void)
401{
402 snd_major = major;
403 snd_ecards_limit = cards_limit;
404 if (register_chrdev(major, "alsa", &snd_fops)) {
405 pr_err("ALSA core: unable to register native major device number %d\n", major);
406 return -EIO;
407 }
408 if (snd_info_init() < 0) {
409 unregister_chrdev(major, "alsa");
410 return -ENOMEM;
411 }
412#ifndef MODULE
413 pr_info("Advanced Linux Sound Architecture Driver Initialized.\n");
414#endif
415 return 0;
416}
417
418static void __exit alsa_sound_exit(void)
419{
420 snd_info_done();
421 unregister_chrdev(major, "alsa");
422}
423
424subsys_initcall(alsa_sound_init);
425module_exit(alsa_sound_exit);
426