[mirror_ubuntu-zesty-kernel.git] / sound / core / sound.c

/*
 *  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/device.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/mutex.h>

#define SNDRV_OS_MINORS 256

static int major = CONFIG_SND_MAJOR;
int snd_major;
EXPORT_SYMBOL(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;
EXPORT_SYMBOL(snd_ecards_limit);

static struct snd_minor *snd_minors[SNDRV_OS_MINORS];
static DEFINE_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);
}

EXPORT_SYMBOL(snd_request_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 */

/**
 * snd_lookup_minor_data - get user data of a registered device
 * @minor: the minor number
 * @type: device type (SNDRV_DEVICE_TYPE_XXX)
 *
 * Checks that a minor device with the specified type is registered, and returns
 * its user data pointer.
 */
void *snd_lookup_minor_data(unsigned int minor, int type)
{
	struct snd_minor *mreg;
	void *private_data;

	if (minor >= ARRAY_SIZE(snd_minors))
		return NULL;
	mutex_lock(&sound_mutex);
	mreg = snd_minors[minor];
	if (mreg && mreg->type == type)
		private_data = mreg->private_data;
	else
		private_data = NULL;
	mutex_unlock(&sound_mutex);
	return private_data;
}

EXPORT_SYMBOL(snd_lookup_minor_data);

static int snd_open(struct inode *inode, struct file *file)
{
	unsigned int minor = iminor(inode);
	struct snd_minor *mptr = NULL;
	const struct file_operations *old_fops;
	int err = 0;

	if (minor >= ARRAY_SIZE(snd_minors))
		return -ENODEV;
	mptr = snd_minors[minor];
	if (mptr == NULL) {
#ifdef CONFIG_KMOD
		int dev = SNDRV_MINOR_DEVICE(minor);
		if (dev == SNDRV_MINOR_CONTROL) {
			/* /dev/aloadC? */
			int card = SNDRV_MINOR_CARD(minor);
			if (snd_cards[card] == NULL)
				snd_request_card(card);
		} else if (dev == SNDRV_MINOR_GLOBAL) {
			/* /dev/aloadSEQ */
			snd_request_other(minor);
		}
#ifndef CONFIG_SND_DYNAMIC_MINORS
		/* /dev/snd/{controlC?,seq} */
		mptr = snd_minors[minor];
		if (mptr == NULL)
#endif
#endif
			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
};

#ifdef CONFIG_SND_DYNAMIC_MINORS
static int snd_find_free_minor(void)
{
	int minor;

	for (minor = 0; minor < ARRAY_SIZE(snd_minors); ++minor) {
		/* skip minors still used statically for autoloading devices */
		if (SNDRV_MINOR_DEVICE(minor) == SNDRV_MINOR_CONTROL ||
		    minor == SNDRV_MINOR_SEQUENCER)
			continue;
		if (!snd_minors[minor])
			return minor;
	}
	return -EBUSY;
}
#else
static int snd_kernel_minor(int type, struct snd_card *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;
}
#endif

/**
 * 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
 * @f_ops: the file operations
 * @private_data: user pointer for f_ops->open()
 * @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, struct snd_card *card, int dev,
			const struct file_operations *f_ops, void *private_data,
			const char *name)
{
	int minor;
	struct snd_minor *preg;
	struct device *device = NULL;

	snd_assert(name, return -EINVAL);
	preg = kmalloc(sizeof(struct snd_minor) + strlen(name) + 1, GFP_KERNEL);
	if (preg == NULL)
		return -ENOMEM;
	preg->type = type;
	preg->card = card ? card->number : -1;
	preg->device = dev;
	preg->f_ops = f_ops;
	preg->private_data = private_data;
	strcpy(preg->name, name);
	mutex_lock(&sound_mutex);
#ifdef CONFIG_SND_DYNAMIC_MINORS
	minor = snd_find_free_minor();
#else
	minor = snd_kernel_minor(type, card, dev);
	if (minor >= 0 && snd_minors[minor])
		minor = -EBUSY;
#endif
	if (minor < 0) {
		mutex_unlock(&sound_mutex);
		kfree(preg);
		return minor;
	}
	snd_minors[minor] = preg;
	if (type != SNDRV_DEVICE_TYPE_CONTROL || preg->card >= 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);

	mutex_unlock(&sound_mutex);
	return 0;
}

EXPORT_SYMBOL(snd_register_device);

/**
 * 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, struct snd_card *card, int dev)
{
	int cardnum, minor;
	struct snd_minor *mptr;

	cardnum = card ? card->number : -1;
	mutex_lock(&sound_mutex);
	for (minor = 0; minor < ARRAY_SIZE(snd_minors); ++minor)
		if ((mptr = snd_minors[minor]) != NULL &&
		    mptr->type == type &&
		    mptr->card == cardnum &&
		    mptr->device == dev)
			break;
	if (minor == ARRAY_SIZE(snd_minors)) {
		mutex_unlock(&sound_mutex);
		return -EINVAL;
	}

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

	snd_minors[minor] = NULL;
	mutex_unlock(&sound_mutex);
	kfree(mptr);
	return 0;
}

EXPORT_SYMBOL(snd_unregister_device);

#ifdef CONFIG_PROC_FS
/*
 *  INFO PART
 */

static struct snd_info_entry *snd_minor_info_entry = NULL;

static const char *snd_device_type_name(int type)
{
	switch (type) {
	case SNDRV_DEVICE_TYPE_CONTROL:
		return "control";
	case SNDRV_DEVICE_TYPE_HWDEP:
		return "hardware dependent";
	case SNDRV_DEVICE_TYPE_RAWMIDI:
		return "raw midi";
	case SNDRV_DEVICE_TYPE_PCM_PLAYBACK:
		return "digital audio playback";
	case SNDRV_DEVICE_TYPE_PCM_CAPTURE:
		return "digital audio capture";
	case SNDRV_DEVICE_TYPE_SEQUENCER:
		return "sequencer";
	case SNDRV_DEVICE_TYPE_TIMER:
		return "timer";
	default:
		return "?";
	}
}

static void snd_minor_info_read(struct snd_info_entry *entry, struct snd_info_buffer *buffer)
{
	int minor;
	struct snd_minor *mptr;

	mutex_lock(&sound_mutex);
	for (minor = 0; minor < SNDRV_OS_MINORS; ++minor) {
		if (!(mptr = snd_minors[minor]))
			continue;
		if (mptr->card >= 0) {
			if (mptr->device >= 0)
				snd_iprintf(buffer, "%3i: [%2i-%2i]: %s\n",
					    minor, mptr->card, mptr->device,
					    snd_device_type_name(mptr->type));
			else
				snd_iprintf(buffer, "%3i: [%2i]   : %s\n",
					    minor, mptr->card,
					    snd_device_type_name(mptr->type));
		} else
			snd_iprintf(buffer, "%3i:        : %s\n", minor,
				    snd_device_type_name(mptr->type));
	}
	mutex_unlock(&sound_mutex);
}

int __init snd_minor_info_init(void)
{
	struct snd_info_entry *entry;

	entry = snd_info_create_module_entry(THIS_MODULE, "devices", NULL);
	if (entry) {
		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;
}
#endif /* CONFIG_PROC_FS */

/*
 *  INIT PART
 */

static int __init alsa_sound_init(void)
{
	short controlnum;

	snd_major = major;
	snd_ecards_limit = cards_limit;
	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();
	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);

	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)
Commit	Line	Data
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>
	35	#include <linux/devfs_fs_kernel.h>
1a60d4c5	36	#include <linux/mutex.h>
1da177e4 LT	37
	38	#define SNDRV_OS_MINORS 256
	39
	40	static int major = CONFIG_SND_MAJOR;
	41	int snd_major;
c0d3fb39 TI	42	EXPORT_SYMBOL(snd_major);
c0d3fb39 TI	43
1da177e4 LT	44	static int cards_limit = 1;
	45	static int device_mode = S_IFCHR \| S_IRUGO \| S_IWUGO;
	46
	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.");
	57	#endif
	58	MODULE_ALIAS_CHARDEV_MAJOR(CONFIG_SND_MAJOR);
	59
	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.
	63	*/
	64	int snd_ecards_limit;
c0d3fb39	65	EXPORT_SYMBOL(snd_ecards_limit);
1da177e4	66
6983b724	67	static struct snd_minor *snd_minors[SNDRV_OS_MINORS];
1a60d4c5	68	static DEFINE_MUTEX(sound_mutex);
1da177e4	69
619e666b	70	extern struct class *sound_class;
1da177e4 LT	71
	72
	73	#ifdef CONFIG_KMOD
	74
	75	/**
	76	* snd_request_card - try to load the card module
	77	* @card: the card number
	78	*
	79	* Tries to load the module "snd-card-X" for the given card number
	80	* via KMOD. Returns immediately if already loaded.
	81	*/
	82	void snd_request_card(int card)
	83	{
	84	int locked;
	85
	86	if (! current->fs->root)
	87	return;
	88	read_lock(&snd_card_rwlock);
	89	locked = snd_cards_lock & (1 << card);
	90	read_unlock(&snd_card_rwlock);
	91	if (locked)
	92	return;
	93	if (card < 0 \|\| card >= cards_limit)
	94	return;
	95	request_module("snd-card-%i", card);
	96	}
	97
c0d3fb39 TI	98	EXPORT_SYMBOL(snd_request_card);
c0d3fb39 TI	99
1da177e4 LT	100	static void snd_request_other(int minor)
	101	{
	102	char *str;
	103
	104	if (! current->fs->root)
	105	return;
	106	switch (minor) {
	107	case SNDRV_MINOR_SEQUENCER: str = "snd-seq"; break;
	108	case SNDRV_MINOR_TIMER: str = "snd-timer"; break;
	109	default: return;
	110	}
	111	request_module(str);
	112	}
	113
	114	#endif /* request_module support */
	115
f87135f5 CL	116	/**
	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)
	120	*
	121	* Checks that a minor device with the specified type is registered, and returns
	122	* its user data pointer.
	123	*/
	124	void *snd_lookup_minor_data(unsigned int minor, int type)
	125	{
	126	struct snd_minor *mreg;
	127	void *private_data;
	128
3a63e444	129	if (minor >= ARRAY_SIZE(snd_minors))
f87135f5	130	return NULL;
1a60d4c5	131	mutex_lock(&sound_mutex);
f87135f5 CL	132	mreg = snd_minors[minor];
	133	if (mreg && mreg->type == type)
	134	private_data = mreg->private_data;
	135	else
	136	private_data = NULL;
1a60d4c5	137	mutex_unlock(&sound_mutex);
f87135f5 CL	138	return private_data;
	139	}
	140
c0d3fb39 TI	141	EXPORT_SYMBOL(snd_lookup_minor_data);
c0d3fb39 TI	142
1da177e4 LT	143	static int snd_open(struct inode inode, struct file file)
1da177e4 LT	144	{
332682b1	145	unsigned int minor = iminor(inode);
512bbd6a	146	struct snd_minor *mptr = NULL;
99ac48f5	147	const struct file_operations *old_fops;
1da177e4 LT	148	int err = 0;
1da177e4 LT	149
3a63e444	150	if (minor >= ARRAY_SIZE(snd_minors))
332682b1 CL	151	return -ENODEV;
	152	mptr = snd_minors[minor];
	153	if (mptr == NULL) {
1da177e4	154	#ifdef CONFIG_KMOD
332682b1 CL	155	int dev = SNDRV_MINOR_DEVICE(minor);
	156	if (dev == SNDRV_MINOR_CONTROL) {
	157	/* /dev/aloadC? */
	158	int card = SNDRV_MINOR_CARD(minor);
1da177e4	159	if (snd_cards[card] == NULL)
332682b1 CL	160	snd_request_card(card);
	161	} else if (dev == SNDRV_MINOR_GLOBAL) {
	162	/* /dev/aloadSEQ */
1da177e4	163	snd_request_other(minor);
332682b1 CL	164	}
	165	#ifndef CONFIG_SND_DYNAMIC_MINORS
	166	/* /dev/snd/{controlC?,seq} */
	167	mptr = snd_minors[minor];
	168	if (mptr == NULL)
	169	#endif
1da177e4	170	#endif
332682b1	171	return -ENODEV;
1da177e4	172	}
1da177e4 LT	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);
	177	if (err) {
	178	fops_put(file->f_op);
	179	file->f_op = fops_get(old_fops);
	180	}
	181	fops_put(old_fops);
	182	return err;
	183	}
	184
	185	static struct file_operations snd_fops =
	186	{
	187	.owner = THIS_MODULE,
	188	.open = snd_open
	189	};
	190
332682b1 CL	191	#ifdef CONFIG_SND_DYNAMIC_MINORS
	192	static int snd_find_free_minor(void)
	193	{
	194	int minor;
	195
	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)
	200	continue;
	201	if (!snd_minors[minor])
	202	return minor;
	203	}
	204	return -EBUSY;
	205	}
	206	#else
512bbd6a	207	static int snd_kernel_minor(int type, struct snd_card *card, int dev)
1da177e4 LT	208	{
	209	int minor;
	210
	211	switch (type) {
	212	case SNDRV_DEVICE_TYPE_SEQUENCER:
	213	case SNDRV_DEVICE_TYPE_TIMER:
	214	minor = type;
	215	break;
	216	case SNDRV_DEVICE_TYPE_CONTROL:
	217	snd_assert(card != NULL, return -EINVAL);
	218	minor = SNDRV_MINOR(card->number, type);
	219	break;
	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);
	226	break;
	227	default:
	228	return -EINVAL;
	229	}
	230	snd_assert(minor >= 0 && minor < SNDRV_OS_MINORS, return -EINVAL);
	231	return minor;
	232	}
332682b1	233	#endif
1da177e4 LT	234
	235	/**
	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
2af677fc	240	* @f_ops: the file operations
f87135f5	241	* @private_data: user pointer for f_ops->open()
1da177e4 LT	242	* @name: the device file name
	243	*
	244	* Registers an ALSA device file for the given card.
	245	* The operators have to be set in reg parameter.
	246	*
	247	* Retrurns zero if successful, or a negative error code on failure.
	248	*/
2af677fc	249	int snd_register_device(int type, struct snd_card *card, int dev,
99ac48f5	250	const struct file_operations f_ops, void private_data,
f87135f5	251	const char *name)
1da177e4	252	{
332682b1	253	int minor;
512bbd6a	254	struct snd_minor *preg;
1da177e4 LT	255	struct device *device = NULL;
1da177e4 LT	256
1da177e4	257	snd_assert(name, return -EINVAL);
6983b724	258	preg = kmalloc(sizeof(struct snd_minor) + strlen(name) + 1, GFP_KERNEL);
1da177e4 LT	259	if (preg == NULL)
1da177e4 LT	260	return -ENOMEM;
2af677fc	261	preg->type = type;
6983b724	262	preg->card = card ? card->number : -1;
1da177e4	263	preg->device = dev;
2af677fc	264	preg->f_ops = f_ops;
f87135f5	265	preg->private_data = private_data;
1da177e4	266	strcpy(preg->name, name);
1a60d4c5	267	mutex_lock(&sound_mutex);
332682b1 CL	268	#ifdef CONFIG_SND_DYNAMIC_MINORS
	269	minor = snd_find_free_minor();
	270	#else
	271	minor = snd_kernel_minor(type, card, dev);
	272	if (minor >= 0 && snd_minors[minor])
	273	minor = -EBUSY;
	274	#endif
	275	if (minor < 0) {
1a60d4c5	276	mutex_unlock(&sound_mutex);
1da177e4	277	kfree(preg);
332682b1	278	return minor;
1da177e4	279	}
6983b724 CL	280	snd_minors[minor] = preg;
6983b724 CL	281	if (type != SNDRV_DEVICE_TYPE_CONTROL \|\| preg->card >= cards_limit)
1da177e4	282	devfs_mk_cdev(MKDEV(major, minor), S_IFCHR \| device_mode, "snd/%s", name);
3e23c658	283	if (card)
1da177e4	284	device = card->dev;
3e23c658	285	class_device_create(sound_class, NULL, MKDEV(major, minor), device, "%s", name);
1da177e4	286
1a60d4c5	287	mutex_unlock(&sound_mutex);
1da177e4 LT	288	return 0;
	289	}
	290
c0d3fb39 TI	291	EXPORT_SYMBOL(snd_register_device);
c0d3fb39 TI	292
1da177e4 LT	293	/**
	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
	298	*
	299	* Unregisters the device file already registered via
	300	* snd_register_device().
	301	*
	302	* Returns zero if sucecessful, or a negative error code on failure
	303	*/
512bbd6a	304	int snd_unregister_device(int type, struct snd_card *card, int dev)
1da177e4	305	{
f87135f5	306	int cardnum, minor;
512bbd6a	307	struct snd_minor *mptr;
1da177e4	308
f87135f5	309	cardnum = card ? card->number : -1;
1a60d4c5	310	mutex_lock(&sound_mutex);
f87135f5 CL	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 &&
	315	mptr->device == dev)
	316	break;
	317	if (minor == ARRAY_SIZE(snd_minors)) {
1a60d4c5	318	mutex_unlock(&sound_mutex);
1da177e4 LT	319	return -EINVAL;
	320	}
	321
6983b724 CL	322	if (mptr->type != SNDRV_DEVICE_TYPE_CONTROL \|\|
6983b724 CL	323	mptr->card >= cards_limit) /* created in sound.c */
1da177e4	324	devfs_remove("snd/%s", mptr->name);
619e666b	325	class_device_destroy(sound_class, MKDEV(major, minor));
1da177e4	326
6983b724	327	snd_minors[minor] = NULL;
1a60d4c5	328	mutex_unlock(&sound_mutex);
1da177e4 LT	329	kfree(mptr);
	330	return 0;
	331	}
	332
c0d3fb39 TI	333	EXPORT_SYMBOL(snd_unregister_device);
c0d3fb39 TI	334
e28563cc	335	#ifdef CONFIG_PROC_FS
1da177e4 LT	336	/*
	337	* INFO PART
	338	*/
	339
512bbd6a	340	static struct snd_info_entry *snd_minor_info_entry = NULL;
1da177e4	341
2af677fc CL	342	static const char *snd_device_type_name(int type)
	343	{
	344	switch (type) {
	345	case SNDRV_DEVICE_TYPE_CONTROL:
	346	return "control";
	347	case SNDRV_DEVICE_TYPE_HWDEP:
	348	return "hardware dependent";
	349	case SNDRV_DEVICE_TYPE_RAWMIDI:
	350	return "raw midi";
	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:
	356	return "sequencer";
	357	case SNDRV_DEVICE_TYPE_TIMER:
	358	return "timer";
	359	default:
	360	return "?";
	361	}
	362	}
	363
512bbd6a	364	static void snd_minor_info_read(struct snd_info_entry entry, struct snd_info_buffer buffer)
1da177e4	365	{
6983b724	366	int minor;
512bbd6a	367	struct snd_minor *mptr;
1da177e4	368
1a60d4c5	369	mutex_lock(&sound_mutex);
6983b724 CL	370	for (minor = 0; minor < SNDRV_OS_MINORS; ++minor) {
	371	if (!(mptr = snd_minors[minor]))
	372	continue;
	373	if (mptr->card >= 0) {
	374	if (mptr->device >= 0)
d001544d	375	snd_iprintf(buffer, "%3i: [%2i-%2i]: %s\n",
6983b724 CL	376	minor, mptr->card, mptr->device,
	377	snd_device_type_name(mptr->type));
	378	else
d001544d	379	snd_iprintf(buffer, "%3i: [%2i] : %s\n",
6983b724 CL	380	minor, mptr->card,
	381	snd_device_type_name(mptr->type));
	382	} else
d001544d	383	snd_iprintf(buffer, "%3i: : %s\n", minor,
6983b724	384	snd_device_type_name(mptr->type));
1da177e4	385	}
1a60d4c5	386	mutex_unlock(&sound_mutex);
1da177e4 LT	387	}
	388
	389	int __init snd_minor_info_init(void)
	390	{
512bbd6a	391	struct snd_info_entry *entry;
1da177e4 LT	392
	393	entry = snd_info_create_module_entry(THIS_MODULE, "devices", NULL);
	394	if (entry) {
1da177e4 LT	395	entry->c.text.read = snd_minor_info_read;
	396	if (snd_info_register(entry) < 0) {
	397	snd_info_free_entry(entry);
	398	entry = NULL;
	399	}
	400	}
	401	snd_minor_info_entry = entry;
	402	return 0;
	403	}
	404
	405	int __exit snd_minor_info_done(void)
	406	{
	407	if (snd_minor_info_entry)
	408	snd_info_unregister(snd_minor_info_entry);
	409	return 0;
	410	}
e28563cc	411	#endif /* CONFIG_PROC_FS */
1da177e4 LT	412
	413	/*
	414	* INIT PART
	415	*/
	416
	417	static int __init alsa_sound_init(void)
	418	{
	419	short controlnum;
1da177e4 LT	420
	421	snd_major = major;
	422	snd_ecards_limit = cards_limit;
1da177e4 LT	423	devfs_mk_dir("snd");
	424	if (register_chrdev(major, "alsa", &snd_fops)) {
	425	snd_printk(KERN_ERR "unable to register native major device number %d\n", major);
	426	devfs_remove("snd");
	427	return -EIO;
	428	}
1da177e4	429	if (snd_info_init() < 0) {
1da177e4 LT	430	unregister_chrdev(major, "alsa");
	431	devfs_remove("snd");
	432	return -ENOMEM;
	433	}
	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);
	437	#ifndef MODULE
	438	printk(KERN_INFO "Advanced Linux Sound Architecture Driver Version " CONFIG_SND_VERSION CONFIG_SND_DATE ".\n");
	439	#endif
	440	return 0;
	441	}
	442
	443	static void __exit alsa_sound_exit(void)
	444	{
	445	short controlnum;
	446
	447	for (controlnum = 0; controlnum < cards_limit; controlnum++)
	448	devfs_remove("snd/controlC%d", controlnum);
	449
	450	snd_info_minor_unregister();
	451	snd_info_done();
1da177e4 LT	452	if (unregister_chrdev(major, "alsa") != 0)
	453	snd_printk(KERN_ERR "unable to unregister major device number %d\n", major);
	454	devfs_remove("snd");
	455	}
	456
	457	module_init(alsa_sound_init)
	458	module_exit(alsa_sound_exit)