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

/*
 *  Device management routines
 *  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 <sound/driver.h>
#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;
}

/**
 * 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
 * callback, dev_unregister or 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 list_head *list;
	struct snd_device *dev;
	
	snd_assert(card != NULL, return -ENXIO);
	snd_assert(device_data != NULL, return -ENXIO);
	list_for_each(list, &card->devices) {
		dev = snd_device(list);
		if (dev->device_data != device_data)
			continue;
		/* unlink */
		list_del(&dev->list);
		if ((dev->state == SNDRV_DEV_REGISTERED ||
		     dev->state == SNDRV_DEV_DISCONNECTED) &&
		    dev->ops->dev_unregister) {
			if (dev->ops->dev_unregister(dev))
				snd_printk(KERN_ERR "device unregister failure\n");
		} else {
			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;
}

/**
 * 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 list_head *list;
	struct snd_device *dev;

	snd_assert(card != NULL, return -ENXIO);
	snd_assert(device_data != NULL, return -ENXIO);
	list_for_each(list, &card->devices) {
		dev = snd_device(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 list_head *list;
	struct snd_device *dev;
	int err;

	snd_assert(card != NULL, return -ENXIO);
	snd_assert(device_data != NULL, return -ENXIO);
	list_for_each(list, &card->devices) {
		dev = snd_device(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;
}

/*
 * register all the devices on the card.
 * called from init.c
 */
int snd_device_register_all(struct snd_card *card)
{
	struct list_head *list;
	struct snd_device *dev;
	int err;
	
	snd_assert(card != NULL, return -ENXIO);
	list_for_each(list, &card->devices) {
		dev = snd_device(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;
	struct list_head *list;
	int err = 0;

	snd_assert(card != NULL, return -ENXIO);
	list_for_each(list, &card->devices) {
		dev = snd_device(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;
	struct list_head *list;
	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(list, &card->devices) {
		dev = snd_device(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	/*
	2	* Device management routines
	3	* Copyright (c) by Jaroslav Kysela <[email protected]>
	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/slab.h>
	24	#include <linux/time.h>
	25	#include <linux/errno.h>
	26	#include <sound/core.h>
	27
	28	/**
	29	* snd_device_new - create an ALSA device component
	30	* @card: the card instance
a3352f01	31	* @type: the device type, SNDRV_DEV_XXX
1da177e4 LT	32	* @device_data: the data pointer of this device
	33	* @ops: the operator table
	34	*
	35	* Creates a new device component for the given data pointer.
	36	* The device will be assigned to the card and managed together
	37	* by the card.
	38	*
	39	* The data pointer plays a role as the identifier, too, so the
	40	* pointer address must be unique and unchanged.
	41	*
	42	* Returns zero if successful, or a negative error code on failure.
	43	*/
512bbd6a TI	44	int snd_device_new(struct snd_card *card, snd_device_type_t type,
512bbd6a TI	45	void device_data, struct snd_device_ops ops)
1da177e4	46	{
512bbd6a	47	struct snd_device *dev;
1da177e4	48
a3352f01 HK	49	snd_assert(card != NULL, return -ENXIO);
	50	snd_assert(device_data != NULL, return -ENXIO);
	51	snd_assert(ops != NULL, return -ENXIO);
ca2c0966	52	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
73e77ba0 TI	53	if (dev == NULL) {
73e77ba0 TI	54	snd_printk(KERN_ERR "Cannot allocate device\n");
1da177e4	55	return -ENOMEM;
73e77ba0	56	}
1da177e4 LT	57	dev->card = card;
	58	dev->type = type;
	59	dev->state = SNDRV_DEV_BUILD;
	60	dev->device_data = device_data;
	61	dev->ops = ops;
	62	list_add(&dev->list, &card->devices); /* add to the head of list */
	63	return 0;
	64	}
	65
	66	/**
	67	* snd_device_free - release the device from the card
	68	* @card: the card instance
	69	* @device_data: the data pointer to release
	70	*
	71	* Removes the device from the list on the card and invokes the
	72	* callback, dev_unregister or dev_free, corresponding to the state.
	73	* Then release the device.
	74	*
	75	* Returns zero if successful, or a negative error code on failure or if the
	76	* device not found.
	77	*/
512bbd6a	78	int snd_device_free(struct snd_card card, void device_data)
1da177e4 LT	79	{
1da177e4 LT	80	struct list_head *list;
512bbd6a	81	struct snd_device *dev;
1da177e4 LT	82
	83	snd_assert(card != NULL, return -ENXIO);
	84	snd_assert(device_data != NULL, return -ENXIO);
	85	list_for_each(list, &card->devices) {
	86	dev = snd_device(list);
	87	if (dev->device_data != device_data)
	88	continue;
	89	/* unlink */
	90	list_del(&dev->list);
512bbd6a TI	91	if ((dev->state == SNDRV_DEV_REGISTERED \|\|
512bbd6a TI	92	dev->state == SNDRV_DEV_DISCONNECTED) &&
1da177e4 LT	93	dev->ops->dev_unregister) {
	94	if (dev->ops->dev_unregister(dev))
	95	snd_printk(KERN_ERR "device unregister failure\n");
	96	} else {
	97	if (dev->ops->dev_free) {
	98	if (dev->ops->dev_free(dev))
	99	snd_printk(KERN_ERR "device free failure\n");
	100	}
	101	}
	102	kfree(dev);
	103	return 0;
	104	}
512bbd6a TI	105	snd_printd("device free %p (from %p), not found\n", device_data,
512bbd6a TI	106	__builtin_return_address(0));
1da177e4 LT	107	return -ENXIO;
	108	}
	109
	110	/**
a3352f01	111	* snd_device_disconnect - disconnect the device
1da177e4 LT	112	* @card: the card instance
	113	* @device_data: the data pointer to disconnect
	114	*
	115	* Turns the device into the disconnection state, invoking
	116	* dev_disconnect callback, if the device was already registered.
	117	*
	118	* Usually called from snd_card_disconnect().
	119	*
	120	* Returns zero if successful, or a negative error code on failure or if the
	121	* device not found.
	122	*/
512bbd6a	123	int snd_device_disconnect(struct snd_card card, void device_data)
1da177e4 LT	124	{
1da177e4 LT	125	struct list_head *list;
512bbd6a	126	struct snd_device *dev;
a3352f01	127
1da177e4 LT	128	snd_assert(card != NULL, return -ENXIO);
	129	snd_assert(device_data != NULL, return -ENXIO);
	130	list_for_each(list, &card->devices) {
	131	dev = snd_device(list);
	132	if (dev->device_data != device_data)
	133	continue;
512bbd6a TI	134	if (dev->state == SNDRV_DEV_REGISTERED &&
512bbd6a TI	135	dev->ops->dev_disconnect) {
1da177e4 LT	136	if (dev->ops->dev_disconnect(dev))
	137	snd_printk(KERN_ERR "device disconnect failure\n");
	138	dev->state = SNDRV_DEV_DISCONNECTED;
	139	}
	140	return 0;
	141	}
512bbd6a TI	142	snd_printd("device disconnect %p (from %p), not found\n", device_data,
512bbd6a TI	143	__builtin_return_address(0));
1da177e4 LT	144	return -ENXIO;
	145	}
	146
	147	/**
	148	* snd_device_register - register the device
	149	* @card: the card instance
	150	* @device_data: the data pointer to register
	151	*
	152	* Registers the device which was already created via
	153	* snd_device_new(). Usually this is called from snd_card_register(),
	154	* but it can be called later if any new devices are created after
	155	* invocation of snd_card_register().
	156	*
	157	* Returns zero if successful, or a negative error code on failure or if the
	158	* device not found.
	159	*/
512bbd6a	160	int snd_device_register(struct snd_card card, void device_data)
1da177e4 LT	161	{
1da177e4 LT	162	struct list_head *list;
512bbd6a	163	struct snd_device *dev;
1da177e4	164	int err;
a3352f01 HK	165
	166	snd_assert(card != NULL, return -ENXIO);
	167	snd_assert(device_data != NULL, return -ENXIO);
1da177e4 LT	168	list_for_each(list, &card->devices) {
	169	dev = snd_device(list);
	170	if (dev->device_data != device_data)
	171	continue;
	172	if (dev->state == SNDRV_DEV_BUILD && dev->ops->dev_register) {
	173	if ((err = dev->ops->dev_register(dev)) < 0)
	174	return err;
	175	dev->state = SNDRV_DEV_REGISTERED;
	176	return 0;
	177	}
73e77ba0	178	snd_printd("snd_device_register busy\n");
1da177e4 LT	179	return -EBUSY;
	180	}
	181	snd_BUG();
	182	return -ENXIO;
	183	}
	184
	185	/*
	186	* register all the devices on the card.
	187	* called from init.c
	188	*/
512bbd6a	189	int snd_device_register_all(struct snd_card *card)
1da177e4 LT	190	{
1da177e4 LT	191	struct list_head *list;
512bbd6a	192	struct snd_device *dev;
1da177e4 LT	193	int err;
	194
	195	snd_assert(card != NULL, return -ENXIO);
3e23c658	196	list_for_each(list, &card->devices) {
1da177e4 LT	197	dev = snd_device(list);
	198	if (dev->state == SNDRV_DEV_BUILD && dev->ops->dev_register) {
	199	if ((err = dev->ops->dev_register(dev)) < 0)
	200	return err;
	201	dev->state = SNDRV_DEV_REGISTERED;
	202	}
	203	}
	204	return 0;
	205	}
	206
	207	/*
	208	* disconnect all the devices on the card.
	209	* called from init.c
	210	*/
512bbd6a	211	int snd_device_disconnect_all(struct snd_card *card)
1da177e4	212	{
512bbd6a	213	struct snd_device *dev;
1da177e4 LT	214	struct list_head *list;
	215	int err = 0;
	216
	217	snd_assert(card != NULL, return -ENXIO);
	218	list_for_each(list, &card->devices) {
	219	dev = snd_device(list);
	220	if (snd_device_disconnect(card, dev->device_data) < 0)
	221	err = -ENXIO;
	222	}
	223	return err;
	224	}
	225
	226	/*
	227	* release all the devices on the card.
	228	* called from init.c
	229	*/
512bbd6a	230	int snd_device_free_all(struct snd_card *card, snd_device_cmd_t cmd)
1da177e4	231	{
512bbd6a	232	struct snd_device *dev;
1da177e4 LT	233	struct list_head *list;
	234	int err;
	235	unsigned int range_low, range_high;
	236
	237	snd_assert(card != NULL, return -ENXIO);
	238	range_low = cmd * SNDRV_DEV_TYPE_RANGE_SIZE;
	239	range_high = range_low + SNDRV_DEV_TYPE_RANGE_SIZE - 1;
	240	__again:
	241	list_for_each(list, &card->devices) {
	242	dev = snd_device(list);
	243	if (dev->type >= range_low && dev->type <= range_high) {
	244	if ((err = snd_device_free(card, dev->device_data)) < 0)
	245	return err;
	246	goto __again;
	247	}
	248	}
	249	return 0;
	250	}