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v4.10.11
  1/*
  2 *  Device management routines
  3 *  Copyright (c) by Jaroslav Kysela <perex@perex.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 <linux/slab.h>
 23#include <linux/time.h>
 24#include <linux/export.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
 31 * @type: the device type, SNDRV_DEV_XXX
 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 * Return: Zero if successful, or a negative error code on failure.
 43 */
 44int snd_device_new(struct snd_card *card, enum snd_device_type type,
 45		   void *device_data, struct snd_device_ops *ops)
 46{
 47	struct snd_device *dev;
 48	struct list_head *p;
 49
 50	if (snd_BUG_ON(!card || !device_data || !ops))
 51		return -ENXIO;
 52	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 53	if (!dev)
 
 54		return -ENOMEM;
 55	INIT_LIST_HEAD(&dev->list);
 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
 62	/* insert the entry in an incrementally sorted list */
 63	list_for_each_prev(p, &card->devices) {
 64		struct snd_device *pdev = list_entry(p, struct snd_device, list);
 65		if ((unsigned int)pdev->type <= (unsigned int)type)
 66			break;
 67	}
 68
 69	list_add(&dev->list, p);
 70	return 0;
 71}
 72EXPORT_SYMBOL(snd_device_new);
 73
 74static void __snd_device_disconnect(struct snd_device *dev)
 75{
 76	if (dev->state == SNDRV_DEV_REGISTERED) {
 77		if (dev->ops->dev_disconnect &&
 78		    dev->ops->dev_disconnect(dev))
 79			dev_err(dev->card->dev, "device disconnect failure\n");
 80		dev->state = SNDRV_DEV_DISCONNECTED;
 81	}
 82}
 83
 84static void __snd_device_free(struct snd_device *dev)
 
 
 
 
 
 
 
 
 
 
 
 
 85{
 86	/* unlink */
 87	list_del(&dev->list);
 88
 89	__snd_device_disconnect(dev);
 90	if (dev->ops->dev_free) {
 91		if (dev->ops->dev_free(dev))
 92			dev_err(dev->card->dev, "device free failure\n");
 
 
 
 
 
 
 
 
 
 
 
 
 
 93	}
 94	kfree(dev);
 
 
 95}
 96
 97static struct snd_device *look_for_dev(struct snd_card *card, void *device_data)
 98{
 99	struct snd_device *dev;
100
101	list_for_each_entry(dev, &card->devices, list)
102		if (dev->device_data == device_data)
103			return dev;
104
105	return NULL;
106}
107
108/**
109 * snd_device_disconnect - disconnect the device
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 * Return: Zero if successful, or a negative error code on failure or if the
119 * device not found.
120 */
121void snd_device_disconnect(struct snd_card *card, void *device_data)
122{
123	struct snd_device *dev;
124
125	if (snd_BUG_ON(!card || !device_data))
126		return;
127	dev = look_for_dev(card, device_data);
128	if (dev)
129		__snd_device_disconnect(dev);
130	else
131		dev_dbg(card->dev, "device disconnect %p (from %pF), not found\n",
132			device_data, __builtin_return_address(0));
133}
134EXPORT_SYMBOL_GPL(snd_device_disconnect);
135
136/**
137 * snd_device_free - release the device from the card
138 * @card: the card instance
139 * @device_data: the data pointer to release
140 *
141 * Removes the device from the list on the card and invokes the
142 * callbacks, dev_disconnect and dev_free, corresponding to the state.
143 * Then release the device.
144 */
145void snd_device_free(struct snd_card *card, void *device_data)
146{
147	struct snd_device *dev;
148	
149	if (snd_BUG_ON(!card || !device_data))
150		return;
151	dev = look_for_dev(card, device_data);
152	if (dev)
153		__snd_device_free(dev);
154	else
155		dev_dbg(card->dev, "device free %p (from %pF), not found\n",
156			device_data, __builtin_return_address(0));
157}
158EXPORT_SYMBOL(snd_device_free);
159
160static int __snd_device_register(struct snd_device *dev)
161{
162	if (dev->state == SNDRV_DEV_BUILD) {
163		if (dev->ops->dev_register) {
164			int err = dev->ops->dev_register(dev);
165			if (err < 0)
166				return err;
167		}
168		dev->state = SNDRV_DEV_REGISTERED;
169	}
170	return 0;
 
 
171}
172
173/**
174 * snd_device_register - register the device
175 * @card: the card instance
176 * @device_data: the data pointer to register
177 *
178 * Registers the device which was already created via
179 * snd_device_new().  Usually this is called from snd_card_register(),
180 * but it can be called later if any new devices are created after
181 * invocation of snd_card_register().
182 *
183 * Return: Zero if successful, or a negative error code on failure or if the
184 * device not found.
185 */
186int snd_device_register(struct snd_card *card, void *device_data)
187{
188	struct snd_device *dev;
 
189
190	if (snd_BUG_ON(!card || !device_data))
191		return -ENXIO;
192	dev = look_for_dev(card, device_data);
193	if (dev)
194		return __snd_device_register(dev);
 
 
 
 
 
 
 
 
 
195	snd_BUG();
196	return -ENXIO;
197}
 
198EXPORT_SYMBOL(snd_device_register);
199
200/*
201 * register all the devices on the card.
202 * called from init.c
203 */
204int snd_device_register_all(struct snd_card *card)
205{
206	struct snd_device *dev;
207	int err;
208	
209	if (snd_BUG_ON(!card))
210		return -ENXIO;
211	list_for_each_entry(dev, &card->devices, list) {
212		err = __snd_device_register(dev);
213		if (err < 0)
214			return err;
 
 
215	}
216	return 0;
217}
218
219/*
220 * disconnect all the devices on the card.
221 * called from init.c
222 */
223void snd_device_disconnect_all(struct snd_card *card)
224{
225	struct snd_device *dev;
 
226
227	if (snd_BUG_ON(!card))
228		return;
229	list_for_each_entry_reverse(dev, &card->devices, list)
230		__snd_device_disconnect(dev);
 
 
 
231}
232
233/*
234 * release all the devices on the card.
235 * called from init.c
236 */
237void snd_device_free_all(struct snd_card *card)
238{
239	struct snd_device *dev, *next;
 
 
240
241	if (snd_BUG_ON(!card))
242		return;
243	list_for_each_entry_safe_reverse(dev, next, &card->devices, list)
244		__snd_device_free(dev);
 
 
 
 
 
 
 
 
 
 
245}
v3.1
  1/*
  2 *  Device management routines
  3 *  Copyright (c) by Jaroslav Kysela <perex@perex.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 <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
 30 * @type: the device type, SNDRV_DEV_XXX
 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 */
 43int snd_device_new(struct snd_card *card, snd_device_type_t type,
 44		   void *device_data, struct snd_device_ops *ops)
 45{
 46	struct snd_device *dev;
 
 47
 48	if (snd_BUG_ON(!card || !device_data || !ops))
 49		return -ENXIO;
 50	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 51	if (dev == NULL) {
 52		snd_printk(KERN_ERR "Cannot allocate device\n");
 53		return -ENOMEM;
 54	}
 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
 64EXPORT_SYMBOL(snd_device_new);
 
 
 
 
 
 
 
 
 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 * callbacks, dev_disconnect and 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 */
 78int snd_device_free(struct snd_card *card, void *device_data)
 79{
 80	struct snd_device *dev;
 81	
 82	if (snd_BUG_ON(!card || !device_data))
 83		return -ENXIO;
 84	list_for_each_entry(dev, &card->devices, list) {
 85		if (dev->device_data != device_data)
 86			continue;
 87		/* unlink */
 88		list_del(&dev->list);
 89		if (dev->state == SNDRV_DEV_REGISTERED &&
 90		    dev->ops->dev_disconnect)
 91			if (dev->ops->dev_disconnect(dev))
 92				snd_printk(KERN_ERR
 93					   "device disconnect failure\n");
 94		if (dev->ops->dev_free) {
 95			if (dev->ops->dev_free(dev))
 96				snd_printk(KERN_ERR "device free failure\n");
 97		}
 98		kfree(dev);
 99		return 0;
100	}
101	snd_printd("device free %p (from %pF), not found\n", device_data,
102		   __builtin_return_address(0));
103	return -ENXIO;
104}
105
106EXPORT_SYMBOL(snd_device_free);
 
 
 
 
 
 
 
 
 
107
108/**
109 * snd_device_disconnect - disconnect the device
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 */
121int snd_device_disconnect(struct snd_card *card, void *device_data)
122{
123	struct snd_device *dev;
124
125	if (snd_BUG_ON(!card || !device_data))
126		return -ENXIO;
127	list_for_each_entry(dev, &card->devices, list) {
128		if (dev->device_data != device_data)
129			continue;
130		if (dev->state == SNDRV_DEV_REGISTERED &&
131		    dev->ops->dev_disconnect) {
132			if (dev->ops->dev_disconnect(dev))
133				snd_printk(KERN_ERR "device disconnect failure\n");
134			dev->state = SNDRV_DEV_DISCONNECTED;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
135		}
136		return 0;
137	}
138	snd_printd("device disconnect %p (from %pF), not found\n", device_data,
139		   __builtin_return_address(0));
140	return -ENXIO;
141}
142
143/**
144 * snd_device_register - register the device
145 * @card: the card instance
146 * @device_data: the data pointer to register
147 *
148 * Registers the device which was already created via
149 * snd_device_new().  Usually this is called from snd_card_register(),
150 * but it can be called later if any new devices are created after
151 * invocation of snd_card_register().
152 *
153 * Returns zero if successful, or a negative error code on failure or if the
154 * device not found.
155 */
156int snd_device_register(struct snd_card *card, void *device_data)
157{
158	struct snd_device *dev;
159	int err;
160
161	if (snd_BUG_ON(!card || !device_data))
162		return -ENXIO;
163	list_for_each_entry(dev, &card->devices, list) {
164		if (dev->device_data != device_data)
165			continue;
166		if (dev->state == SNDRV_DEV_BUILD && dev->ops->dev_register) {
167			if ((err = dev->ops->dev_register(dev)) < 0)
168				return err;
169			dev->state = SNDRV_DEV_REGISTERED;
170			return 0;
171		}
172		snd_printd("snd_device_register busy\n");
173		return -EBUSY;
174	}
175	snd_BUG();
176	return -ENXIO;
177}
178
179EXPORT_SYMBOL(snd_device_register);
180
181/*
182 * register all the devices on the card.
183 * called from init.c
184 */
185int snd_device_register_all(struct snd_card *card)
186{
187	struct snd_device *dev;
188	int err;
189	
190	if (snd_BUG_ON(!card))
191		return -ENXIO;
192	list_for_each_entry(dev, &card->devices, list) {
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 */
206int snd_device_disconnect_all(struct snd_card *card)
207{
208	struct snd_device *dev;
209	int err = 0;
210
211	if (snd_BUG_ON(!card))
212		return -ENXIO;
213	list_for_each_entry(dev, &card->devices, list) {
214		if (snd_device_disconnect(card, dev->device_data) < 0)
215			err = -ENXIO;
216	}
217	return err;
218}
219
220/*
221 * release all the devices on the card.
222 * called from init.c
223 */
224int snd_device_free_all(struct snd_card *card, snd_device_cmd_t cmd)
225{
226	struct snd_device *dev;
227	int err;
228	unsigned int range_low, range_high, type;
229
230	if (snd_BUG_ON(!card))
231		return -ENXIO;
232	range_low = (__force unsigned int)cmd * SNDRV_DEV_TYPE_RANGE_SIZE;
233	range_high = range_low + SNDRV_DEV_TYPE_RANGE_SIZE - 1;
234      __again:
235	list_for_each_entry(dev, &card->devices, list) {
236		type = (__force unsigned int)dev->type;
237		if (type >= range_low && type <= range_high) {
238			if ((err = snd_device_free(card, dev->device_data)) < 0)
239				return err;
240			goto __again;
241		}
242	}
243	return 0;
244}