[linux.git] / sound / core / sound.c

/*
 *  Advanced Linux Sound Architecture
 *  Copyright (c) by Jaroslav Kysela <[email protected]>
 *
 *
 *   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 <linux/init.h>
#include <linux/slab.h>
#include <linux/smp_lock.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/mutex.h>

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

static int cards_limit = 1;

MODULE_AUTHOR("Jaroslav Kysela <[email protected]>");
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.");
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);

#ifdef CONFIG_MODULES

/**
 * 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 request_module.  Returns immediately if already loaded.
 */
void snd_request_card(int card)
{
	if (snd_card_locked(card))
		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;

	switch (minor) {
	case SNDRV_MINOR_SEQUENCER:	str = "snd-seq";	break;
	case SNDRV_MINOR_TIMER:		str = "snd-timer";	break;
	default:			return;
	}
	request_module(str);
}

#endif	/* modular kernel */

/**
 * 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_MODULES
		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 == NULL) {
		file->f_op = old_fops;
		return -ENODEV;
	}
	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;
}


/* BKL pushdown: nasty #ifdef avoidance wrapper */
static int snd_open(struct inode *inode, struct file *file)
{
	int ret;

	lock_kernel();
	ret = __snd_open(inode, file);
	unlock_kernel();
	return ret;
}

static const 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:
		if (snd_BUG_ON(!card))
			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:
		if (snd_BUG_ON(!card))
			return -EINVAL;
		minor = SNDRV_MINOR(card->number, type + dev);
		break;
	default:
		return -EINVAL;
	}
	if (snd_BUG_ON(minor < 0 || minor >= SNDRV_OS_MINORS))
		return -EINVAL;
	return minor;
}
#endif

/**
 * snd_register_device_for_dev - 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
 * @device: the &struct device to link this new device to
 *
 * Registers an ALSA device file for the given card.
 * The operators have to be set in reg parameter.
 *
 * Returns zero if successful, or a negative error code on failure.
 */
int snd_register_device_for_dev(int type, struct snd_card *card, int dev,
				const struct file_operations *f_ops,
				void *private_data,
				const char *name, struct device *device)
{
	int minor;
	struct snd_minor *preg;

	if (snd_BUG_ON(!name))
		return -EINVAL;
	preg = kmalloc(sizeof *preg, 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;
	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;
	preg->dev = device_create(sound_class, device, MKDEV(major, minor),
				  private_data, "%s", name);
	if (IS_ERR(preg->dev)) {
		snd_minors[minor] = NULL;
		mutex_unlock(&sound_mutex);
		minor = PTR_ERR(preg->dev);
		kfree(preg);
		return minor;
	}

	mutex_unlock(&sound_mutex);
	return 0;
}

EXPORT_SYMBOL(snd_register_device_for_dev);

/* find the matching minor record
 * return the index of snd_minor, or -1 if not found
 */
static int find_snd_minor(int type, struct snd_card *card, int dev)
{
	int cardnum, minor;
	struct snd_minor *mptr;

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

/**
 * 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 minor;

	mutex_lock(&sound_mutex);
	minor = find_snd_minor(type, card, dev);
	if (minor < 0) {
		mutex_unlock(&sound_mutex);
		return -EINVAL;
	}

	device_destroy(sound_class, MKDEV(major, minor));

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

EXPORT_SYMBOL(snd_unregister_device);

int snd_add_device_sysfs_file(int type, struct snd_card *card, int dev,
			      struct device_attribute *attr)
{
	int minor, ret = -EINVAL;
	struct device *d;

	mutex_lock(&sound_mutex);
	minor = find_snd_minor(type, card, dev);
	if (minor >= 0 && (d = snd_minors[minor]->dev) != NULL)
		ret = device_create_file(d, attr);
	mutex_unlock(&sound_mutex);
	return ret;

}

EXPORT_SYMBOL(snd_add_device_sysfs_file);

#ifdef CONFIG_PROC_FS
/*
 *  INFO PART
 */

static struct snd_info_entry *snd_minor_info_entry;

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)
{
	snd_info_free_entry(snd_minor_info_entry);
	return 0;
}
#endif /* CONFIG_PROC_FS */

/*
 *  INIT PART
 */

static int __init alsa_sound_init(void)
{
	snd_major = major;
	snd_ecards_limit = cards_limit;
	if (register_chrdev(major, "alsa", &snd_fops)) {
		snd_printk(KERN_ERR "unable to register native major device number %d\n", major);
		return -EIO;
	}
	if (snd_info_init() < 0) {
		unregister_chrdev(major, "alsa");
		return -ENOMEM;
	}
	snd_info_minor_register();
#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)
{
	snd_info_minor_unregister();
	snd_info_done();
	unregister_chrdev(major, "alsa");
}

subsys_initcall(alsa_sound_init);
module_exit(alsa_sound_exit);
Commit	Line	Data
1da177e4 LT	1	/*
1da177e4 LT	2	* Advanced Linux Sound Architecture
c1017a4c	3	* Copyright (c) by Jaroslav Kysela <[email protected]>
1da177e4 LT	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
1da177e4 LT	22	#include <linux/init.h>
1da177e4 LT	23	#include <linux/slab.h>
78a3c3d7	24	#include <linux/smp_lock.h>
1da177e4	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	36
1da177e4 LT	37	static int major = CONFIG_SND_MAJOR;
1da177e4 LT	38	int snd_major;
c0d3fb39 TI	39	EXPORT_SYMBOL(snd_major);
c0d3fb39 TI	40
1da177e4	41	static int cards_limit = 1;
1da177e4	42
c1017a4c	43	MODULE_AUTHOR("Jaroslav Kysela <[email protected]>");
1da177e4 LT	44	MODULE_DESCRIPTION("Advanced Linux Sound Architecture driver for soundcards.");
	45	MODULE_LICENSE("GPL");
	46	module_param(major, int, 0444);
	47	MODULE_PARM_DESC(major, "Major # for sound driver.");
	48	module_param(cards_limit, int, 0444);
	49	MODULE_PARM_DESC(cards_limit, "Count of auto-loadable soundcards.");
1da177e4 LT	50	MODULE_ALIAS_CHARDEV_MAJOR(CONFIG_SND_MAJOR);
	51
	52	/* this one holds the actual max. card number currently available.
	53	* as default, it's identical with cards_limit option. when more
	54	* modules are loaded manually, this limit number increases, too.
	55	*/
	56	int snd_ecards_limit;
c0d3fb39	57	EXPORT_SYMBOL(snd_ecards_limit);
1da177e4	58
6983b724	59	static struct snd_minor *snd_minors[SNDRV_OS_MINORS];
1a60d4c5	60	static DEFINE_MUTEX(sound_mutex);
1da177e4	61
ee2da997	62	#ifdef CONFIG_MODULES
1da177e4 LT	63
	64	/**
	65	* snd_request_card - try to load the card module
	66	* @card: the card number
	67	*
	68	* Tries to load the module "snd-card-X" for the given card number
ee2da997	69	* via request_module. Returns immediately if already loaded.
1da177e4 LT	70	*/
	71	void snd_request_card(int card)
	72	{
746df948	73	if (snd_card_locked(card))
1da177e4 LT	74	return;
	75	if (card < 0 \|\| card >= cards_limit)
	76	return;
	77	request_module("snd-card-%i", card);
	78	}
	79
c0d3fb39 TI	80	EXPORT_SYMBOL(snd_request_card);
c0d3fb39 TI	81
1da177e4 LT	82	static void snd_request_other(int minor)
	83	{
	84	char *str;
	85
1da177e4 LT	86	switch (minor) {
	87	case SNDRV_MINOR_SEQUENCER: str = "snd-seq"; break;
	88	case SNDRV_MINOR_TIMER: str = "snd-timer"; break;
	89	default: return;
	90	}
	91	request_module(str);
	92	}
	93
ee2da997	94	#endif /* modular kernel */
1da177e4	95
f87135f5 CL	96	/**
	97	* snd_lookup_minor_data - get user data of a registered device
	98	* @minor: the minor number
	99	* @type: device type (SNDRV_DEVICE_TYPE_XXX)
	100	*
	101	* Checks that a minor device with the specified type is registered, and returns
	102	* its user data pointer.
	103	*/
	104	void *snd_lookup_minor_data(unsigned int minor, int type)
	105	{
	106	struct snd_minor *mreg;
	107	void *private_data;
	108
3a63e444	109	if (minor >= ARRAY_SIZE(snd_minors))
f87135f5	110	return NULL;
1a60d4c5	111	mutex_lock(&sound_mutex);
f87135f5 CL	112	mreg = snd_minors[minor];
	113	if (mreg && mreg->type == type)
	114	private_data = mreg->private_data;
	115	else
	116	private_data = NULL;
1a60d4c5	117	mutex_unlock(&sound_mutex);
f87135f5 CL	118	return private_data;
	119	}
	120
c0d3fb39 TI	121	EXPORT_SYMBOL(snd_lookup_minor_data);
c0d3fb39 TI	122
78a3c3d7	123	static int __snd_open(struct inode inode, struct file file)
1da177e4	124	{
332682b1	125	unsigned int minor = iminor(inode);
512bbd6a	126	struct snd_minor *mptr = NULL;
99ac48f5	127	const struct file_operations *old_fops;
1da177e4 LT	128	int err = 0;
1da177e4 LT	129
3a63e444	130	if (minor >= ARRAY_SIZE(snd_minors))
332682b1 CL	131	return -ENODEV;
	132	mptr = snd_minors[minor];
	133	if (mptr == NULL) {
ee2da997	134	#ifdef CONFIG_MODULES
332682b1 CL	135	int dev = SNDRV_MINOR_DEVICE(minor);
	136	if (dev == SNDRV_MINOR_CONTROL) {
	137	/* /dev/aloadC? */
	138	int card = SNDRV_MINOR_CARD(minor);
1da177e4	139	if (snd_cards[card] == NULL)
332682b1 CL	140	snd_request_card(card);
	141	} else if (dev == SNDRV_MINOR_GLOBAL) {
	142	/* /dev/aloadSEQ */
1da177e4	143	snd_request_other(minor);
332682b1 CL	144	}
	145	#ifndef CONFIG_SND_DYNAMIC_MINORS
	146	/* /dev/snd/{controlC?,seq} */
	147	mptr = snd_minors[minor];
	148	if (mptr == NULL)
	149	#endif
1da177e4	150	#endif
332682b1	151	return -ENODEV;
1da177e4	152	}
1da177e4 LT	153	old_fops = file->f_op;
1da177e4 LT	154	file->f_op = fops_get(mptr->f_ops);
f41ced8f LP	155	if (file->f_op == NULL) {
	156	file->f_op = old_fops;
	157	return -ENODEV;
	158	}
1da177e4 LT	159	if (file->f_op->open)
	160	err = file->f_op->open(inode, file);
	161	if (err) {
	162	fops_put(file->f_op);
	163	file->f_op = fops_get(old_fops);
	164	}
	165	fops_put(old_fops);
	166	return err;
	167	}
	168
78a3c3d7 JC	169
	170	/* BKL pushdown: nasty #ifdef avoidance wrapper */
	171	static int snd_open(struct inode inode, struct file file)
	172	{
	173	int ret;
	174
	175	lock_kernel();
	176	ret = __snd_open(inode, file);
	177	unlock_kernel();
	178	return ret;
	179	}
	180
9c2e08c5	181	static const struct file_operations snd_fops =
1da177e4 LT	182	{
	183	.owner = THIS_MODULE,
	184	.open = snd_open
	185	};
	186
332682b1 CL	187	#ifdef CONFIG_SND_DYNAMIC_MINORS
	188	static int snd_find_free_minor(void)
	189	{
	190	int minor;
	191
	192	for (minor = 0; minor < ARRAY_SIZE(snd_minors); ++minor) {
	193	/* skip minors still used statically for autoloading devices */
	194	if (SNDRV_MINOR_DEVICE(minor) == SNDRV_MINOR_CONTROL \|\|
	195	minor == SNDRV_MINOR_SEQUENCER)
	196	continue;
	197	if (!snd_minors[minor])
	198	return minor;
	199	}
	200	return -EBUSY;
	201	}
	202	#else
512bbd6a	203	static int snd_kernel_minor(int type, struct snd_card *card, int dev)
1da177e4 LT	204	{
	205	int minor;
	206
	207	switch (type) {
	208	case SNDRV_DEVICE_TYPE_SEQUENCER:
	209	case SNDRV_DEVICE_TYPE_TIMER:
	210	minor = type;
	211	break;
	212	case SNDRV_DEVICE_TYPE_CONTROL:
7eaa943c TI	213	if (snd_BUG_ON(!card))
7eaa943c TI	214	return -EINVAL;
1da177e4 LT	215	minor = SNDRV_MINOR(card->number, type);
	216	break;
	217	case SNDRV_DEVICE_TYPE_HWDEP:
	218	case SNDRV_DEVICE_TYPE_RAWMIDI:
	219	case SNDRV_DEVICE_TYPE_PCM_PLAYBACK:
	220	case SNDRV_DEVICE_TYPE_PCM_CAPTURE:
7eaa943c TI	221	if (snd_BUG_ON(!card))
7eaa943c TI	222	return -EINVAL;
1da177e4 LT	223	minor = SNDRV_MINOR(card->number, type + dev);
	224	break;
	225	default:
	226	return -EINVAL;
	227	}
7eaa943c TI	228	if (snd_BUG_ON(minor < 0 \|\| minor >= SNDRV_OS_MINORS))
7eaa943c TI	229	return -EINVAL;
1da177e4 LT	230	return minor;
1da177e4 LT	231	}
332682b1	232	#endif
1da177e4 LT	233
1da177e4 LT	234	/**
12b131c4	235	* snd_register_device_for_dev - Register the ALSA device file for the card
1da177e4 LT	236	* @type: the device type, SNDRV_DEVICE_TYPE_XXX
	237	* @card: the card instance
	238	* @dev: the device index
2af677fc	239	* @f_ops: the file operations
f87135f5	240	* @private_data: user pointer for f_ops->open()
1da177e4	241	* @name: the device file name
12b131c4	242	* @device: the &struct device to link this new device to
1da177e4 LT	243	*
	244	* Registers an ALSA device file for the given card.
	245	* The operators have to be set in reg parameter.
	246	*
12b131c4	247	* Returns zero if successful, or a negative error code on failure.
1da177e4	248	*/
12b131c4 JB	249	int snd_register_device_for_dev(int type, struct snd_card *card, int dev,
	250	const struct file_operations *f_ops,
	251	void *private_data,
	252	const char name, struct device device)
1da177e4	253	{
332682b1	254	int minor;
512bbd6a	255	struct snd_minor *preg;
1da177e4	256
7eaa943c TI	257	if (snd_BUG_ON(!name))
7eaa943c TI	258	return -EINVAL;
562b590d	259	preg = kmalloc(sizeof *preg, GFP_KERNEL);
1da177e4 LT	260	if (preg == NULL)
1da177e4 LT	261	return -ENOMEM;
2af677fc	262	preg->type = type;
6983b724	263	preg->card = card ? card->number : -1;
1da177e4	264	preg->device = dev;
2af677fc	265	preg->f_ops = f_ops;
f87135f5	266	preg->private_data = private_data;
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	280	snd_minors[minor] = preg;
abe9ab8f GKH	281	preg->dev = device_create(sound_class, device, MKDEV(major, minor),
abe9ab8f GKH	282	private_data, "%s", name);
2469049e MK	283	if (IS_ERR(preg->dev)) {
	284	snd_minors[minor] = NULL;
	285	mutex_unlock(&sound_mutex);
	286	minor = PTR_ERR(preg->dev);
	287	kfree(preg);
	288	return minor;
	289	}
	290
1a60d4c5	291	mutex_unlock(&sound_mutex);
1da177e4 LT	292	return 0;
	293	}
	294
12b131c4	295	EXPORT_SYMBOL(snd_register_device_for_dev);
c0d3fb39	296
9d19f48c TI	297	/* find the matching minor record
	298	* return the index of snd_minor, or -1 if not found
	299	*/
	300	static int find_snd_minor(int type, struct snd_card *card, int dev)
	301	{
	302	int cardnum, minor;
	303	struct snd_minor *mptr;
	304
	305	cardnum = card ? card->number : -1;
	306	for (minor = 0; minor < ARRAY_SIZE(snd_minors); ++minor)
	307	if ((mptr = snd_minors[minor]) != NULL &&
	308	mptr->type == type &&
	309	mptr->card == cardnum &&
	310	mptr->device == dev)
	311	return minor;
	312	return -1;
	313	}
	314
1da177e4 LT	315	/**
	316	* snd_unregister_device - unregister the device on the given card
	317	* @type: the device type, SNDRV_DEVICE_TYPE_XXX
	318	* @card: the card instance
	319	* @dev: the device index
	320	*
	321	* Unregisters the device file already registered via
	322	* snd_register_device().
	323	*
	324	* Returns zero if sucecessful, or a negative error code on failure
	325	*/
512bbd6a	326	int snd_unregister_device(int type, struct snd_card *card, int dev)
1da177e4	327	{
9d19f48c	328	int minor;
1da177e4	329
1a60d4c5	330	mutex_lock(&sound_mutex);
9d19f48c TI	331	minor = find_snd_minor(type, card, dev);
9d19f48c TI	332	if (minor < 0) {
1a60d4c5	333	mutex_unlock(&sound_mutex);
1da177e4 LT	334	return -EINVAL;
	335	}
	336
d80f19fa	337	device_destroy(sound_class, MKDEV(major, minor));
1da177e4	338
9d19f48c	339	kfree(snd_minors[minor]);
6983b724	340	snd_minors[minor] = NULL;
1a60d4c5	341	mutex_unlock(&sound_mutex);
1da177e4 LT	342	return 0;
	343	}
	344
c0d3fb39 TI	345	EXPORT_SYMBOL(snd_unregister_device);
c0d3fb39 TI	346
9d19f48c	347	int snd_add_device_sysfs_file(int type, struct snd_card *card, int dev,
d80f19fa	348	struct device_attribute *attr)
9d19f48c TI	349	{
9d19f48c TI	350	int minor, ret = -EINVAL;
d80f19fa	351	struct device *d;
9d19f48c TI	352
	353	mutex_lock(&sound_mutex);
	354	minor = find_snd_minor(type, card, dev);
d80f19fa GKH	355	if (minor >= 0 && (d = snd_minors[minor]->dev) != NULL)
d80f19fa GKH	356	ret = device_create_file(d, attr);
9d19f48c TI	357	mutex_unlock(&sound_mutex);
	358	return ret;
	359
	360	}
	361
	362	EXPORT_SYMBOL(snd_add_device_sysfs_file);
	363
e28563cc	364	#ifdef CONFIG_PROC_FS
1da177e4 LT	365	/*
	366	* INFO PART
	367	*/
	368
6581f4e7	369	static struct snd_info_entry *snd_minor_info_entry;
1da177e4	370
2af677fc CL	371	static const char *snd_device_type_name(int type)
	372	{
	373	switch (type) {
	374	case SNDRV_DEVICE_TYPE_CONTROL:
	375	return "control";
	376	case SNDRV_DEVICE_TYPE_HWDEP:
	377	return "hardware dependent";
	378	case SNDRV_DEVICE_TYPE_RAWMIDI:
	379	return "raw midi";
	380	case SNDRV_DEVICE_TYPE_PCM_PLAYBACK:
	381	return "digital audio playback";
	382	case SNDRV_DEVICE_TYPE_PCM_CAPTURE:
	383	return "digital audio capture";
	384	case SNDRV_DEVICE_TYPE_SEQUENCER:
	385	return "sequencer";
	386	case SNDRV_DEVICE_TYPE_TIMER:
	387	return "timer";
	388	default:
	389	return "?";
	390	}
	391	}
	392
512bbd6a	393	static void snd_minor_info_read(struct snd_info_entry entry, struct snd_info_buffer buffer)
1da177e4	394	{
6983b724	395	int minor;
512bbd6a	396	struct snd_minor *mptr;
1da177e4	397
1a60d4c5	398	mutex_lock(&sound_mutex);
6983b724 CL	399	for (minor = 0; minor < SNDRV_OS_MINORS; ++minor) {
	400	if (!(mptr = snd_minors[minor]))
	401	continue;
	402	if (mptr->card >= 0) {
	403	if (mptr->device >= 0)
d001544d	404	snd_iprintf(buffer, "%3i: [%2i-%2i]: %s\n",
6983b724 CL	405	minor, mptr->card, mptr->device,
	406	snd_device_type_name(mptr->type));
	407	else
d001544d	408	snd_iprintf(buffer, "%3i: [%2i] : %s\n",
6983b724 CL	409	minor, mptr->card,
	410	snd_device_type_name(mptr->type));
	411	} else
d001544d	412	snd_iprintf(buffer, "%3i: : %s\n", minor,
6983b724	413	snd_device_type_name(mptr->type));
1da177e4	414	}
1a60d4c5	415	mutex_unlock(&sound_mutex);
1da177e4 LT	416	}
	417
	418	int __init snd_minor_info_init(void)
	419	{
512bbd6a	420	struct snd_info_entry *entry;
1da177e4 LT	421
	422	entry = snd_info_create_module_entry(THIS_MODULE, "devices", NULL);
	423	if (entry) {
1da177e4 LT	424	entry->c.text.read = snd_minor_info_read;
	425	if (snd_info_register(entry) < 0) {
	426	snd_info_free_entry(entry);
	427	entry = NULL;
	428	}
	429	}
	430	snd_minor_info_entry = entry;
	431	return 0;
	432	}
	433
	434	int __exit snd_minor_info_done(void)
	435	{
746d4a02	436	snd_info_free_entry(snd_minor_info_entry);
1da177e4 LT	437	return 0;
1da177e4 LT	438	}
e28563cc	439	#endif /* CONFIG_PROC_FS */
1da177e4 LT	440
	441	/*
	442	* INIT PART
	443	*/
	444
	445	static int __init alsa_sound_init(void)
	446	{
1da177e4 LT	447	snd_major = major;
1da177e4 LT	448	snd_ecards_limit = cards_limit;
1da177e4 LT	449	if (register_chrdev(major, "alsa", &snd_fops)) {
1da177e4 LT	450	snd_printk(KERN_ERR "unable to register native major device number %d\n", major);
1da177e4 LT	451	return -EIO;
1da177e4 LT	452	}
1da177e4	453	if (snd_info_init() < 0) {
1da177e4	454	unregister_chrdev(major, "alsa");
1da177e4 LT	455	return -ENOMEM;
	456	}
	457	snd_info_minor_register();
1da177e4 LT	458	#ifndef MODULE
	459	printk(KERN_INFO "Advanced Linux Sound Architecture Driver Version " CONFIG_SND_VERSION CONFIG_SND_DATE ".\n");
	460	#endif
	461	return 0;
	462	}
	463
	464	static void __exit alsa_sound_exit(void)
	465	{
1da177e4 LT	466	snd_info_minor_unregister();
1da177e4 LT	467	snd_info_done();
68fc4fab	468	unregister_chrdev(major, "alsa");
1da177e4 LT	469	}
1da177e4 LT	470
c181a13a TLSC	471	subsys_initcall(alsa_sound_init);
c181a13a TLSC	472	module_exit(alsa_sound_exit);