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

/*
 *  Device management routines
 *  Copyright (c) by Jaroslav Kysela <perex@perex.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 <linux/slab.h>
#include <linux/time.h>
#include <linux/errno.h>
#include <sound/core.h>

/**
 * snd_device_new - create an ALSA device component
 * @card: the card instance
 * @type: the device type, SNDRV_DEV_XXX
 * @device_data: the data pointer of this device
 * @ops: the operator table
 *
 * Creates a new device component for the given data pointer.
 * The device will be assigned to the card and managed together
 * by the card.
 *
 * The data pointer plays a role as the identifier, too, so the
 * pointer address must be unique and unchanged.
 *
 * Returns zero if successful, or a negative error code on failure.
 */
int snd_device_new(struct snd_card *card, snd_device_type_t type,
		   void *device_data, struct snd_device_ops *ops)
{
	struct snd_device *dev;

	snd_assert(card != NULL, return -ENXIO);
	snd_assert(device_data != NULL, return -ENXIO);
	snd_assert(ops != NULL, return -ENXIO);
	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
	if (dev == NULL) {
		snd_printk(KERN_ERR "Cannot allocate device\n");
		return -ENOMEM;
	}
	dev->card = card;
	dev->type = type;
	dev->state = SNDRV_DEV_BUILD;
	dev->device_data = device_data;
	dev->ops = ops;
	list_add(&dev->list, &card->devices);	/* add to the head of list */
	return 0;
}

EXPORT_SYMBOL(snd_device_new);

/**
 * snd_device_free - release the device from the card
 * @card: the card instance
 * @device_data: the data pointer to release
 *
 * Removes the device from the list on the card and invokes the
 * callbacks, dev_disconnect and dev_free, corresponding to the state.
 * Then release the device.
 *
 * Returns zero if successful, or a negative error code on failure or if the
 * device not found.
 */
int snd_device_free(struct snd_card *card, void *device_data)
{
	struct snd_device *dev;
	
	snd_assert(card != NULL, return -ENXIO);
	snd_assert(device_data != NULL, return -ENXIO);
	list_for_each_entry(dev, &card->devices, list) {
		if (dev->device_data != device_data)
			continue;
		/* unlink */
		list_del(&dev->list);
		if (dev->state == SNDRV_DEV_REGISTERED &&
		    dev->ops->dev_disconnect)
			if (dev->ops->dev_disconnect(dev))
				snd_printk(KERN_ERR
					   "device disconnect failure\n");
		if (dev->ops->dev_free) {
			if (dev->ops->dev_free(dev))
				snd_printk(KERN_ERR "device free failure\n");
		}
		kfree(dev);
		return 0;
	}
	snd_printd("device free %p (from %p), not found\n", device_data,
		   __builtin_return_address(0));
	return -ENXIO;
}

EXPORT_SYMBOL(snd_device_free);

/**
 * snd_device_disconnect - disconnect the device
 * @card: the card instance
 * @device_data: the data pointer to disconnect
 *
 * Turns the device into the disconnection state, invoking
 * dev_disconnect callback, if the device was already registered.
 *
 * Usually called from snd_card_disconnect().
 *
 * Returns zero if successful, or a negative error code on failure or if the
 * device not found.
 */
int snd_device_disconnect(struct snd_card *card, void *device_data)
{
	struct snd_device *dev;

	snd_assert(card != NULL, return -ENXIO);
	snd_assert(device_data != NULL, return -ENXIO);
	list_for_each_entry(dev, &card->devices, list) {
		if (dev->device_data != device_data)
			continue;
		if (dev->state == SNDRV_DEV_REGISTERED &&
		    dev->ops->dev_disconnect) {
			if (dev->ops->dev_disconnect(dev))
				snd_printk(KERN_ERR "device disconnect failure\n");
			dev->state = SNDRV_DEV_DISCONNECTED;
		}
		return 0;
	}
	snd_printd("device disconnect %p (from %p), not found\n", device_data,
		   __builtin_return_address(0));
	return -ENXIO;
}

/**
 * snd_device_register - register the device
 * @card: the card instance
 * @device_data: the data pointer to register
 *
 * Registers the device which was already created via
 * snd_device_new().  Usually this is called from snd_card_register(),
 * but it can be called later if any new devices are created after
 * invocation of snd_card_register().
 *
 * Returns zero if successful, or a negative error code on failure or if the
 * device not found.
 */
int snd_device_register(struct snd_card *card, void *device_data)
{
	struct snd_device *dev;
	int err;

	snd_assert(card != NULL, return -ENXIO);
	snd_assert(device_data != NULL, return -ENXIO);
	list_for_each_entry(dev, &card->devices, list) {
		if (dev->device_data != device_data)
			continue;
		if (dev->state == SNDRV_DEV_BUILD && dev->ops->dev_register) {
			if ((err = dev->ops->dev_register(dev)) < 0)
				return err;
			dev->state = SNDRV_DEV_REGISTERED;
			return 0;
		}
		snd_printd("snd_device_register busy\n");
		return -EBUSY;
	}
	snd_BUG();
	return -ENXIO;
}

EXPORT_SYMBOL(snd_device_register);

/*
 * register all the devices on the card.
 * called from init.c
 */
int snd_device_register_all(struct snd_card *card)
{
	struct snd_device *dev;
	int err;
	
	snd_assert(card != NULL, return -ENXIO);
	list_for_each_entry(dev, &card->devices, list) {
		if (dev->state == SNDRV_DEV_BUILD && dev->ops->dev_register) {
			if ((err = dev->ops->dev_register(dev)) < 0)
				return err;
			dev->state = SNDRV_DEV_REGISTERED;
		}
	}
	return 0;
}

/*
 * disconnect all the devices on the card.
 * called from init.c
 */
int snd_device_disconnect_all(struct snd_card *card)
{
	struct snd_device *dev;
	int err = 0;

	snd_assert(card != NULL, return -ENXIO);
	list_for_each_entry(dev, &card->devices, list) {
		if (snd_device_disconnect(card, dev->device_data) < 0)
			err = -ENXIO;
	}
	return err;
}

/*
 * release all the devices on the card.
 * called from init.c
 */
int snd_device_free_all(struct snd_card *card, snd_device_cmd_t cmd)
{
	struct snd_device *dev;
	int err;
	unsigned int range_low, range_high;

	snd_assert(card != NULL, return -ENXIO);
	range_low = cmd * SNDRV_DEV_TYPE_RANGE_SIZE;
	range_high = range_low + SNDRV_DEV_TYPE_RANGE_SIZE - 1;
      __again:
	list_for_each_entry(dev, &card->devices, list) {
		if (dev->type >= range_low && dev->type <= range_high) {
			if ((err = snd_device_free(card, dev->device_data)) < 0)
				return err;
			goto __again;
		}
	}
	return 0;
}
Commit	Line	Data
1da177e4 LT	1	/*
1da177e4 LT	2	* Device management routines
c1017a4c	3	* Copyright (c) by Jaroslav Kysela <perex@perex.cz>
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/slab.h>
	23	#include <linux/time.h>
	24	#include <linux/errno.h>
	25	#include <sound/core.h>
	26
	27	/**
	28	* snd_device_new - create an ALSA device component
	29	* @card: the card instance
a3352f01	30	* @type: the device type, SNDRV_DEV_XXX
1da177e4 LT	31	* @device_data: the data pointer of this device
	32	* @ops: the operator table
	33	*
	34	* Creates a new device component for the given data pointer.
	35	* The device will be assigned to the card and managed together
	36	* by the card.
	37	*
	38	* The data pointer plays a role as the identifier, too, so the
	39	* pointer address must be unique and unchanged.
	40	*
	41	* Returns zero if successful, or a negative error code on failure.
	42	*/
512bbd6a TI	43	int snd_device_new(struct snd_card *card, snd_device_type_t type,
512bbd6a TI	44	void device_data, struct snd_device_ops ops)
1da177e4	45	{
512bbd6a	46	struct snd_device *dev;
1da177e4	47
a3352f01 HK	48	snd_assert(card != NULL, return -ENXIO);
	49	snd_assert(device_data != NULL, return -ENXIO);
	50	snd_assert(ops != NULL, return -ENXIO);
ca2c0966	51	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
73e77ba0 TI	52	if (dev == NULL) {
73e77ba0 TI	53	snd_printk(KERN_ERR "Cannot allocate device\n");
1da177e4	54	return -ENOMEM;
73e77ba0	55	}
1da177e4 LT	56	dev->card = card;
	57	dev->type = type;
	58	dev->state = SNDRV_DEV_BUILD;
	59	dev->device_data = device_data;
	60	dev->ops = ops;
	61	list_add(&dev->list, &card->devices); /* add to the head of list */
	62	return 0;
	63	}
	64
c0d3fb39 TI	65	EXPORT_SYMBOL(snd_device_new);
c0d3fb39 TI	66
1da177e4 LT	67	/**
	68	* snd_device_free - release the device from the card
	69	* @card: the card instance
	70	* @device_data: the data pointer to release
	71	*
	72	* Removes the device from the list on the card and invokes the
c461482c	73	* callbacks, dev_disconnect and dev_free, corresponding to the state.
1da177e4 LT	74	* Then release the device.
	75	*
	76	* Returns zero if successful, or a negative error code on failure or if the
	77	* device not found.
	78	*/
512bbd6a	79	int snd_device_free(struct snd_card card, void device_data)
1da177e4	80	{
512bbd6a	81	struct snd_device *dev;
1da177e4 LT	82
	83	snd_assert(card != NULL, return -ENXIO);
	84	snd_assert(device_data != NULL, return -ENXIO);
9244b2c3	85	list_for_each_entry(dev, &card->devices, list) {
1da177e4 LT	86	if (dev->device_data != device_data)
	87	continue;
	88	/* unlink */
	89	list_del(&dev->list);
c461482c TI	90	if (dev->state == SNDRV_DEV_REGISTERED &&
	91	dev->ops->dev_disconnect)
	92	if (dev->ops->dev_disconnect(dev))
	93	snd_printk(KERN_ERR
	94	"device disconnect failure\n");
	95	if (dev->ops->dev_free) {
	96	if (dev->ops->dev_free(dev))
	97	snd_printk(KERN_ERR "device free failure\n");
1da177e4 LT	98	}
	99	kfree(dev);
	100	return 0;
	101	}
512bbd6a TI	102	snd_printd("device free %p (from %p), not found\n", device_data,
512bbd6a TI	103	__builtin_return_address(0));
1da177e4 LT	104	return -ENXIO;
	105	}
	106
c0d3fb39 TI	107	EXPORT_SYMBOL(snd_device_free);
c0d3fb39 TI	108
1da177e4	109	/**
a3352f01	110	* snd_device_disconnect - disconnect the device
1da177e4 LT	111	* @card: the card instance
	112	* @device_data: the data pointer to disconnect
	113	*
	114	* Turns the device into the disconnection state, invoking
	115	* dev_disconnect callback, if the device was already registered.
	116	*
	117	* Usually called from snd_card_disconnect().
	118	*
	119	* Returns zero if successful, or a negative error code on failure or if the
	120	* device not found.
	121	*/
512bbd6a	122	int snd_device_disconnect(struct snd_card card, void device_data)
1da177e4	123	{
512bbd6a	124	struct snd_device *dev;
a3352f01	125
1da177e4 LT	126	snd_assert(card != NULL, return -ENXIO);
1da177e4 LT	127	snd_assert(device_data != NULL, return -ENXIO);
9244b2c3	128	list_for_each_entry(dev, &card->devices, list) {
1da177e4 LT	129	if (dev->device_data != device_data)
1da177e4 LT	130	continue;
512bbd6a TI	131	if (dev->state == SNDRV_DEV_REGISTERED &&
512bbd6a TI	132	dev->ops->dev_disconnect) {
1da177e4 LT	133	if (dev->ops->dev_disconnect(dev))
	134	snd_printk(KERN_ERR "device disconnect failure\n");
	135	dev->state = SNDRV_DEV_DISCONNECTED;
	136	}
	137	return 0;
	138	}
512bbd6a TI	139	snd_printd("device disconnect %p (from %p), not found\n", device_data,
512bbd6a TI	140	__builtin_return_address(0));
1da177e4 LT	141	return -ENXIO;
	142	}
	143
	144	/**
	145	* snd_device_register - register the device
	146	* @card: the card instance
	147	* @device_data: the data pointer to register
	148	*
	149	* Registers the device which was already created via
	150	* snd_device_new(). Usually this is called from snd_card_register(),
	151	* but it can be called later if any new devices are created after
	152	* invocation of snd_card_register().
	153	*
	154	* Returns zero if successful, or a negative error code on failure or if the
	155	* device not found.
	156	*/
512bbd6a	157	int snd_device_register(struct snd_card card, void device_data)
1da177e4	158	{
512bbd6a	159	struct snd_device *dev;
1da177e4	160	int err;
a3352f01 HK	161
	162	snd_assert(card != NULL, return -ENXIO);
	163	snd_assert(device_data != NULL, return -ENXIO);
9244b2c3	164	list_for_each_entry(dev, &card->devices, list) {
1da177e4 LT	165	if (dev->device_data != device_data)
	166	continue;
	167	if (dev->state == SNDRV_DEV_BUILD && dev->ops->dev_register) {
	168	if ((err = dev->ops->dev_register(dev)) < 0)
	169	return err;
	170	dev->state = SNDRV_DEV_REGISTERED;
	171	return 0;
	172	}
73e77ba0	173	snd_printd("snd_device_register busy\n");
1da177e4 LT	174	return -EBUSY;
	175	}
	176	snd_BUG();
	177	return -ENXIO;
	178	}
	179
c0d3fb39 TI	180	EXPORT_SYMBOL(snd_device_register);
c0d3fb39 TI	181
1da177e4 LT	182	/*
	183	* register all the devices on the card.
	184	* called from init.c
	185	*/
512bbd6a	186	int snd_device_register_all(struct snd_card *card)
1da177e4	187	{
512bbd6a	188	struct snd_device *dev;
1da177e4 LT	189	int err;
	190
	191	snd_assert(card != NULL, return -ENXIO);
9244b2c3	192	list_for_each_entry(dev, &card->devices, list) {
1da177e4 LT	193	if (dev->state == SNDRV_DEV_BUILD && dev->ops->dev_register) {
	194	if ((err = dev->ops->dev_register(dev)) < 0)
	195	return err;
	196	dev->state = SNDRV_DEV_REGISTERED;
	197	}
	198	}
	199	return 0;
	200	}
	201
	202	/*
	203	* disconnect all the devices on the card.
	204	* called from init.c
	205	*/
512bbd6a	206	int snd_device_disconnect_all(struct snd_card *card)
1da177e4	207	{
512bbd6a	208	struct snd_device *dev;
1da177e4 LT	209	int err = 0;
	210
	211	snd_assert(card != NULL, return -ENXIO);
9244b2c3	212	list_for_each_entry(dev, &card->devices, list) {
1da177e4 LT	213	if (snd_device_disconnect(card, dev->device_data) < 0)
	214	err = -ENXIO;
	215	}
	216	return err;
	217	}
	218
	219	/*
	220	* release all the devices on the card.
	221	* called from init.c
	222	*/
512bbd6a	223	int snd_device_free_all(struct snd_card *card, snd_device_cmd_t cmd)
1da177e4	224	{
512bbd6a	225	struct snd_device *dev;
1da177e4 LT	226	int err;
	227	unsigned int range_low, range_high;
	228
	229	snd_assert(card != NULL, return -ENXIO);
	230	range_low = cmd * SNDRV_DEV_TYPE_RANGE_SIZE;
	231	range_high = range_low + SNDRV_DEV_TYPE_RANGE_SIZE - 1;
	232	__again:
9244b2c3	233	list_for_each_entry(dev, &card->devices, list) {
1da177e4 LT	234	if (dev->type >= range_low && dev->type <= range_high) {
	235	if ((err = snd_device_free(card, dev->device_data)) < 0)
	236	return err;
	237	goto __again;
	238	}
	239	}
	240	return 0;
	241	}