[mirror_ubuntu-bionic-kernel.git] / sound / core / device.c

/*
 *  Device management routines
 *  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/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)
		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;
		}
		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 <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/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);
1da177e4 LT	53	if (dev == NULL)
	54	return -ENOMEM;
	55	dev->card = card;
	56	dev->type = type;
	57	dev->state = SNDRV_DEV_BUILD;
	58	dev->device_data = device_data;
	59	dev->ops = ops;
	60	list_add(&dev->list, &card->devices); /* add to the head of list */
	61	return 0;
	62	}
	63
	64	/**
	65	* snd_device_free - release the device from the card
	66	* @card: the card instance
	67	* @device_data: the data pointer to release
	68	*
	69	* Removes the device from the list on the card and invokes the
	70	* callback, dev_unregister or dev_free, corresponding to the state.
	71	* Then release the device.
	72	*
	73	* Returns zero if successful, or a negative error code on failure or if the
	74	* device not found.
	75	*/
512bbd6a	76	int snd_device_free(struct snd_card card, void device_data)
1da177e4 LT	77	{
1da177e4 LT	78	struct list_head *list;
512bbd6a	79	struct snd_device *dev;
1da177e4 LT	80
	81	snd_assert(card != NULL, return -ENXIO);
	82	snd_assert(device_data != NULL, return -ENXIO);
	83	list_for_each(list, &card->devices) {
	84	dev = snd_device(list);
	85	if (dev->device_data != device_data)
	86	continue;
	87	/* unlink */
	88	list_del(&dev->list);
512bbd6a TI	89	if ((dev->state == SNDRV_DEV_REGISTERED \|\|
512bbd6a TI	90	dev->state == SNDRV_DEV_DISCONNECTED) &&
1da177e4 LT	91	dev->ops->dev_unregister) {
	92	if (dev->ops->dev_unregister(dev))
	93	snd_printk(KERN_ERR "device unregister failure\n");
	94	} else {
	95	if (dev->ops->dev_free) {
	96	if (dev->ops->dev_free(dev))
	97	snd_printk(KERN_ERR "device free failure\n");
	98	}
	99	}
	100	kfree(dev);
	101	return 0;
	102	}
512bbd6a TI	103	snd_printd("device free %p (from %p), not found\n", device_data,
512bbd6a TI	104	__builtin_return_address(0));
1da177e4 LT	105	return -ENXIO;
	106	}
	107
	108	/**
a3352f01	109	* snd_device_disconnect - disconnect the device
1da177e4 LT	110	* @card: the card instance
	111	* @device_data: the data pointer to disconnect
	112	*
	113	* Turns the device into the disconnection state, invoking
	114	* dev_disconnect callback, if the device was already registered.
	115	*
	116	* Usually called from snd_card_disconnect().
	117	*
	118	* Returns zero if successful, or a negative error code on failure or if the
	119	* device not found.
	120	*/
512bbd6a	121	int snd_device_disconnect(struct snd_card card, void device_data)
1da177e4 LT	122	{
1da177e4 LT	123	struct list_head *list;
512bbd6a	124	struct snd_device *dev;
a3352f01	125
1da177e4 LT	126	snd_assert(card != NULL, return -ENXIO);
	127	snd_assert(device_data != NULL, return -ENXIO);
	128	list_for_each(list, &card->devices) {
	129	dev = snd_device(list);
	130	if (dev->device_data != device_data)
	131	continue;
512bbd6a TI	132	if (dev->state == SNDRV_DEV_REGISTERED &&
512bbd6a TI	133	dev->ops->dev_disconnect) {
1da177e4 LT	134	if (dev->ops->dev_disconnect(dev))
	135	snd_printk(KERN_ERR "device disconnect failure\n");
	136	dev->state = SNDRV_DEV_DISCONNECTED;
	137	}
	138	return 0;
	139	}
512bbd6a TI	140	snd_printd("device disconnect %p (from %p), not found\n", device_data,
512bbd6a TI	141	__builtin_return_address(0));
1da177e4 LT	142	return -ENXIO;
	143	}
	144
	145	/**
	146	* snd_device_register - register the device
	147	* @card: the card instance
	148	* @device_data: the data pointer to register
	149	*
	150	* Registers the device which was already created via
	151	* snd_device_new(). Usually this is called from snd_card_register(),
	152	* but it can be called later if any new devices are created after
	153	* invocation of snd_card_register().
	154	*
	155	* Returns zero if successful, or a negative error code on failure or if the
	156	* device not found.
	157	*/
512bbd6a	158	int snd_device_register(struct snd_card card, void device_data)
1da177e4 LT	159	{
1da177e4 LT	160	struct list_head *list;
512bbd6a	161	struct snd_device *dev;
1da177e4	162	int err;
a3352f01 HK	163
	164	snd_assert(card != NULL, return -ENXIO);
	165	snd_assert(device_data != NULL, return -ENXIO);
1da177e4 LT	166	list_for_each(list, &card->devices) {
	167	dev = snd_device(list);
	168	if (dev->device_data != device_data)
	169	continue;
	170	if (dev->state == SNDRV_DEV_BUILD && dev->ops->dev_register) {
	171	if ((err = dev->ops->dev_register(dev)) < 0)
	172	return err;
	173	dev->state = SNDRV_DEV_REGISTERED;
	174	return 0;
	175	}
	176	return -EBUSY;
	177	}
	178	snd_BUG();
	179	return -ENXIO;
	180	}
	181
	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 LT	187	{
1da177e4 LT	188	struct list_head *list;
512bbd6a	189	struct snd_device *dev;
1da177e4 LT	190	int err;
	191
	192	snd_assert(card != NULL, return -ENXIO);
	193	list_for_each(list, &card->devices) {
	194	dev = snd_device(list);
	195	if (dev->state == SNDRV_DEV_BUILD && dev->ops->dev_register) {
	196	if ((err = dev->ops->dev_register(dev)) < 0)
	197	return err;
	198	dev->state = SNDRV_DEV_REGISTERED;
	199	}
	200	}
	201	return 0;
	202	}
	203
	204	/*
	205	* disconnect all the devices on the card.
	206	* called from init.c
	207	*/
512bbd6a	208	int snd_device_disconnect_all(struct snd_card *card)
1da177e4	209	{
512bbd6a	210	struct snd_device *dev;
1da177e4 LT	211	struct list_head *list;
	212	int err = 0;
	213
	214	snd_assert(card != NULL, return -ENXIO);
	215	list_for_each(list, &card->devices) {
	216	dev = snd_device(list);
	217	if (snd_device_disconnect(card, dev->device_data) < 0)
	218	err = -ENXIO;
	219	}
	220	return err;
	221	}
	222
	223	/*
	224	* release all the devices on the card.
	225	* called from init.c
	226	*/
512bbd6a	227	int snd_device_free_all(struct snd_card *card, snd_device_cmd_t cmd)
1da177e4	228	{
512bbd6a	229	struct snd_device *dev;
1da177e4 LT	230	struct list_head *list;
	231	int err;
	232	unsigned int range_low, range_high;
	233
	234	snd_assert(card != NULL, return -ENXIO);
	235	range_low = cmd * SNDRV_DEV_TYPE_RANGE_SIZE;
	236	range_high = range_low + SNDRV_DEV_TYPE_RANGE_SIZE - 1;
	237	__again:
	238	list_for_each(list, &card->devices) {
	239	dev = snd_device(list);
	240	if (dev->type >= range_low && dev->type <= range_high) {
	241	if ((err = snd_device_free(card, dev->device_data)) < 0)
	242	return err;
	243	goto __again;
	244	}
	245	}
	246	return 0;
	247	}