2 * Advanced Linux Sound Architecture
3 * Copyright (c) by Jaroslav Kysela <perex@suse.cz>
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.
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.
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
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/devfs_fs_kernel.h>
36 #include <linux/mutex.h>
38 #define SNDRV_OS_MINORS 256
40 static int major = CONFIG_SND_MAJOR;
42 EXPORT_SYMBOL(snd_major);
44 static int cards_limit = 1;
45 static int device_mode = S_IFCHR | S_IRUGO | S_IWUGO;
47 MODULE_AUTHOR("Jaroslav Kysela <perex@suse.cz>");
48 MODULE_DESCRIPTION("Advanced Linux Sound Architecture driver for soundcards.");
49 MODULE_LICENSE("GPL");
50 module_param(major, int, 0444);
51 MODULE_PARM_DESC(major, "Major # for sound driver.");
52 module_param(cards_limit, int, 0444);
53 MODULE_PARM_DESC(cards_limit, "Count of auto-loadable soundcards.");
54 #ifdef CONFIG_DEVFS_FS
55 module_param(device_mode, int, 0444);
56 MODULE_PARM_DESC(device_mode, "Device file permission mask for devfs.");
58 MODULE_ALIAS_CHARDEV_MAJOR(CONFIG_SND_MAJOR);
60 /* this one holds the actual max. card number currently available.
61 * as default, it's identical with cards_limit option. when more
62 * modules are loaded manually, this limit number increases, too.
65 EXPORT_SYMBOL(snd_ecards_limit);
67 static struct snd_minor *snd_minors[SNDRV_OS_MINORS];
68 static DEFINE_MUTEX(sound_mutex);
70 extern struct class *sound_class;
76 * snd_request_card - try to load the card module
77 * @card: the card number
79 * Tries to load the module "snd-card-X" for the given card number
80 * via KMOD. Returns immediately if already loaded.
82 void snd_request_card(int card)
86 if (! current->fs->root)
88 read_lock(&snd_card_rwlock);
89 locked = snd_cards_lock & (1 << card);
90 read_unlock(&snd_card_rwlock);
93 if (card < 0 || card >= cards_limit)
95 request_module("snd-card-%i", card);
98 EXPORT_SYMBOL(snd_request_card);
100 static void snd_request_other(int minor)
104 if (! current->fs->root)
107 case SNDRV_MINOR_SEQUENCER: str = "snd-seq"; break;
108 case SNDRV_MINOR_TIMER: str = "snd-timer"; break;
114 #endif /* request_module support */
117 * snd_lookup_minor_data - get user data of a registered device
118 * @minor: the minor number
119 * @type: device type (SNDRV_DEVICE_TYPE_XXX)
121 * Checks that a minor device with the specified type is registered, and returns
122 * its user data pointer.
124 void *snd_lookup_minor_data(unsigned int minor, int type)
126 struct snd_minor *mreg;
129 if (minor >= ARRAY_SIZE(snd_minors))
131 mutex_lock(&sound_mutex);
132 mreg = snd_minors[minor];
133 if (mreg && mreg->type == type)
134 private_data = mreg->private_data;
137 mutex_unlock(&sound_mutex);
141 EXPORT_SYMBOL(snd_lookup_minor_data);
143 static int snd_open(struct inode *inode, struct file *file)
145 unsigned int minor = iminor(inode);
146 struct snd_minor *mptr = NULL;
147 const struct file_operations *old_fops;
150 if (minor >= ARRAY_SIZE(snd_minors))
152 mptr = snd_minors[minor];
155 int dev = SNDRV_MINOR_DEVICE(minor);
156 if (dev == SNDRV_MINOR_CONTROL) {
158 int card = SNDRV_MINOR_CARD(minor);
159 if (snd_cards[card] == NULL)
160 snd_request_card(card);
161 } else if (dev == SNDRV_MINOR_GLOBAL) {
163 snd_request_other(minor);
165 #ifndef CONFIG_SND_DYNAMIC_MINORS
166 /* /dev/snd/{controlC?,seq} */
167 mptr = snd_minors[minor];
173 old_fops = file->f_op;
174 file->f_op = fops_get(mptr->f_ops);
175 if (file->f_op->open)
176 err = file->f_op->open(inode, file);
178 fops_put(file->f_op);
179 file->f_op = fops_get(old_fops);
185 static struct file_operations snd_fops =
187 .owner = THIS_MODULE,
191 #ifdef CONFIG_SND_DYNAMIC_MINORS
192 static int snd_find_free_minor(void)
196 for (minor = 0; minor < ARRAY_SIZE(snd_minors); ++minor) {
197 /* skip minors still used statically for autoloading devices */
198 if (SNDRV_MINOR_DEVICE(minor) == SNDRV_MINOR_CONTROL ||
199 minor == SNDRV_MINOR_SEQUENCER)
201 if (!snd_minors[minor])
207 static int snd_kernel_minor(int type, struct snd_card *card, int dev)
212 case SNDRV_DEVICE_TYPE_SEQUENCER:
213 case SNDRV_DEVICE_TYPE_TIMER:
216 case SNDRV_DEVICE_TYPE_CONTROL:
217 snd_assert(card != NULL, return -EINVAL);
218 minor = SNDRV_MINOR(card->number, type);
220 case SNDRV_DEVICE_TYPE_HWDEP:
221 case SNDRV_DEVICE_TYPE_RAWMIDI:
222 case SNDRV_DEVICE_TYPE_PCM_PLAYBACK:
223 case SNDRV_DEVICE_TYPE_PCM_CAPTURE:
224 snd_assert(card != NULL, return -EINVAL);
225 minor = SNDRV_MINOR(card->number, type + dev);
230 snd_assert(minor >= 0 && minor < SNDRV_OS_MINORS, return -EINVAL);
236 * snd_register_device - Register the ALSA device file for the card
237 * @type: the device type, SNDRV_DEVICE_TYPE_XXX
238 * @card: the card instance
239 * @dev: the device index
240 * @f_ops: the file operations
241 * @private_data: user pointer for f_ops->open()
242 * @name: the device file name
244 * Registers an ALSA device file for the given card.
245 * The operators have to be set in reg parameter.
247 * Retrurns zero if successful, or a negative error code on failure.
249 int snd_register_device(int type, struct snd_card *card, int dev,
250 const struct file_operations *f_ops, void *private_data,
254 struct snd_minor *preg;
255 struct device *device = NULL;
257 snd_assert(name, return -EINVAL);
258 preg = kmalloc(sizeof(struct snd_minor) + strlen(name) + 1, GFP_KERNEL);
262 preg->card = card ? card->number : -1;
265 preg->private_data = private_data;
266 strcpy(preg->name, name);
267 mutex_lock(&sound_mutex);
268 #ifdef CONFIG_SND_DYNAMIC_MINORS
269 minor = snd_find_free_minor();
271 minor = snd_kernel_minor(type, card, dev);
272 if (minor >= 0 && snd_minors[minor])
276 mutex_unlock(&sound_mutex);
280 snd_minors[minor] = preg;
281 if (type != SNDRV_DEVICE_TYPE_CONTROL || preg->card >= cards_limit)
282 devfs_mk_cdev(MKDEV(major, minor), S_IFCHR | device_mode, "snd/%s", name);
285 class_device_create(sound_class, NULL, MKDEV(major, minor), device, "%s", name);
287 mutex_unlock(&sound_mutex);
291 EXPORT_SYMBOL(snd_register_device);
294 * snd_unregister_device - unregister the device on the given card
295 * @type: the device type, SNDRV_DEVICE_TYPE_XXX
296 * @card: the card instance
297 * @dev: the device index
299 * Unregisters the device file already registered via
300 * snd_register_device().
302 * Returns zero if sucecessful, or a negative error code on failure
304 int snd_unregister_device(int type, struct snd_card *card, int dev)
307 struct snd_minor *mptr;
309 cardnum = card ? card->number : -1;
310 mutex_lock(&sound_mutex);
311 for (minor = 0; minor < ARRAY_SIZE(snd_minors); ++minor)
312 if ((mptr = snd_minors[minor]) != NULL &&
313 mptr->type == type &&
314 mptr->card == cardnum &&
317 if (minor == ARRAY_SIZE(snd_minors)) {
318 mutex_unlock(&sound_mutex);
322 if (mptr->type != SNDRV_DEVICE_TYPE_CONTROL ||
323 mptr->card >= cards_limit) /* created in sound.c */
324 devfs_remove("snd/%s", mptr->name);
325 class_device_destroy(sound_class, MKDEV(major, minor));
327 snd_minors[minor] = NULL;
328 mutex_unlock(&sound_mutex);
333 EXPORT_SYMBOL(snd_unregister_device);
335 #ifdef CONFIG_PROC_FS
340 static struct snd_info_entry *snd_minor_info_entry = NULL;
342 static const char *snd_device_type_name(int type)
345 case SNDRV_DEVICE_TYPE_CONTROL:
347 case SNDRV_DEVICE_TYPE_HWDEP:
348 return "hardware dependent";
349 case SNDRV_DEVICE_TYPE_RAWMIDI:
351 case SNDRV_DEVICE_TYPE_PCM_PLAYBACK:
352 return "digital audio playback";
353 case SNDRV_DEVICE_TYPE_PCM_CAPTURE:
354 return "digital audio capture";
355 case SNDRV_DEVICE_TYPE_SEQUENCER:
357 case SNDRV_DEVICE_TYPE_TIMER:
364 static void snd_minor_info_read(struct snd_info_entry *entry, struct snd_info_buffer *buffer)
367 struct snd_minor *mptr;
369 mutex_lock(&sound_mutex);
370 for (minor = 0; minor < SNDRV_OS_MINORS; ++minor) {
371 if (!(mptr = snd_minors[minor]))
373 if (mptr->card >= 0) {
374 if (mptr->device >= 0)
375 snd_iprintf(buffer, "%3i: [%2i-%2i]: %s\n",
376 minor, mptr->card, mptr->device,
377 snd_device_type_name(mptr->type));
379 snd_iprintf(buffer, "%3i: [%2i] : %s\n",
381 snd_device_type_name(mptr->type));
383 snd_iprintf(buffer, "%3i: : %s\n", minor,
384 snd_device_type_name(mptr->type));
386 mutex_unlock(&sound_mutex);
389 int __init snd_minor_info_init(void)
391 struct snd_info_entry *entry;
393 entry = snd_info_create_module_entry(THIS_MODULE, "devices", NULL);
395 entry->c.text.read = snd_minor_info_read;
396 if (snd_info_register(entry) < 0) {
397 snd_info_free_entry(entry);
401 snd_minor_info_entry = entry;
405 int __exit snd_minor_info_done(void)
407 if (snd_minor_info_entry)
408 snd_info_unregister(snd_minor_info_entry);
411 #endif /* CONFIG_PROC_FS */
417 static int __init alsa_sound_init(void)
422 snd_ecards_limit = cards_limit;
424 if (register_chrdev(major, "alsa", &snd_fops)) {
425 snd_printk(KERN_ERR "unable to register native major device number %d\n", major);
429 if (snd_info_init() < 0) {
430 unregister_chrdev(major, "alsa");
434 snd_info_minor_register();
435 for (controlnum = 0; controlnum < cards_limit; controlnum++)
436 devfs_mk_cdev(MKDEV(major, controlnum<<5), S_IFCHR | device_mode, "snd/controlC%d", controlnum);
438 printk(KERN_INFO "Advanced Linux Sound Architecture Driver Version " CONFIG_SND_VERSION CONFIG_SND_DATE ".\n");
443 static void __exit alsa_sound_exit(void)
447 for (controlnum = 0; controlnum < cards_limit; controlnum++)
448 devfs_remove("snd/controlC%d", controlnum);
450 snd_info_minor_unregister();
452 if (unregister_chrdev(major, "alsa") != 0)
453 snd_printk(KERN_ERR "unable to unregister major device number %d\n", major);
457 module_init(alsa_sound_init)
458 module_exit(alsa_sound_exit)