Merge branch 'drm-patches' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied...
[linux-2.6] / sound / core / device.c
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
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  * Returns zero if successful, or a negative error code on failure.
43  */
44 int snd_device_new(struct snd_card *card, snd_device_type_t type,
45                    void *device_data, struct snd_device_ops *ops)
46 {
47         struct snd_device *dev;
48
49         snd_assert(card != NULL, return -ENXIO);
50         snd_assert(device_data != NULL, return -ENXIO);
51         snd_assert(ops != NULL, return -ENXIO);
52         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
53         if (dev == NULL) {
54                 snd_printk(KERN_ERR "Cannot allocate device\n");
55                 return -ENOMEM;
56         }
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 EXPORT_SYMBOL(snd_device_new);
67
68 /**
69  * snd_device_free - release the device from the card
70  * @card: the card instance
71  * @device_data: the data pointer to release
72  *
73  * Removes the device from the list on the card and invokes the
74  * callbacks, dev_disconnect and dev_free, corresponding to the state.
75  * Then release the device.
76  *
77  * Returns zero if successful, or a negative error code on failure or if the
78  * device not found.
79  */
80 int snd_device_free(struct snd_card *card, void *device_data)
81 {
82         struct list_head *list;
83         struct snd_device *dev;
84         
85         snd_assert(card != NULL, return -ENXIO);
86         snd_assert(device_data != NULL, return -ENXIO);
87         list_for_each(list, &card->devices) {
88                 dev = snd_device(list);
89                 if (dev->device_data != device_data)
90                         continue;
91                 /* unlink */
92                 list_del(&dev->list);
93                 if (dev->state == SNDRV_DEV_REGISTERED &&
94                     dev->ops->dev_disconnect)
95                         if (dev->ops->dev_disconnect(dev))
96                                 snd_printk(KERN_ERR
97                                            "device disconnect failure\n");
98                 if (dev->ops->dev_free) {
99                         if (dev->ops->dev_free(dev))
100                                 snd_printk(KERN_ERR "device free failure\n");
101                 }
102                 kfree(dev);
103                 return 0;
104         }
105         snd_printd("device free %p (from %p), not found\n", device_data,
106                    __builtin_return_address(0));
107         return -ENXIO;
108 }
109
110 EXPORT_SYMBOL(snd_device_free);
111
112 /**
113  * snd_device_disconnect - disconnect the device
114  * @card: the card instance
115  * @device_data: the data pointer to disconnect
116  *
117  * Turns the device into the disconnection state, invoking
118  * dev_disconnect callback, if the device was already registered.
119  *
120  * Usually called from snd_card_disconnect().
121  *
122  * Returns zero if successful, or a negative error code on failure or if the
123  * device not found.
124  */
125 int snd_device_disconnect(struct snd_card *card, void *device_data)
126 {
127         struct list_head *list;
128         struct snd_device *dev;
129
130         snd_assert(card != NULL, return -ENXIO);
131         snd_assert(device_data != NULL, return -ENXIO);
132         list_for_each(list, &card->devices) {
133                 dev = snd_device(list);
134                 if (dev->device_data != device_data)
135                         continue;
136                 if (dev->state == SNDRV_DEV_REGISTERED &&
137                     dev->ops->dev_disconnect) {
138                         if (dev->ops->dev_disconnect(dev))
139                                 snd_printk(KERN_ERR "device disconnect failure\n");
140                         dev->state = SNDRV_DEV_DISCONNECTED;
141                 }
142                 return 0;
143         }
144         snd_printd("device disconnect %p (from %p), not found\n", device_data,
145                    __builtin_return_address(0));
146         return -ENXIO;
147 }
148
149 /**
150  * snd_device_register - register the device
151  * @card: the card instance
152  * @device_data: the data pointer to register
153  *
154  * Registers the device which was already created via
155  * snd_device_new().  Usually this is called from snd_card_register(),
156  * but it can be called later if any new devices are created after
157  * invocation of snd_card_register().
158  *
159  * Returns zero if successful, or a negative error code on failure or if the
160  * device not found.
161  */
162 int snd_device_register(struct snd_card *card, void *device_data)
163 {
164         struct list_head *list;
165         struct snd_device *dev;
166         int err;
167
168         snd_assert(card != NULL, return -ENXIO);
169         snd_assert(device_data != NULL, return -ENXIO);
170         list_for_each(list, &card->devices) {
171                 dev = snd_device(list);
172                 if (dev->device_data != device_data)
173                         continue;
174                 if (dev->state == SNDRV_DEV_BUILD && dev->ops->dev_register) {
175                         if ((err = dev->ops->dev_register(dev)) < 0)
176                                 return err;
177                         dev->state = SNDRV_DEV_REGISTERED;
178                         return 0;
179                 }
180                 snd_printd("snd_device_register busy\n");
181                 return -EBUSY;
182         }
183         snd_BUG();
184         return -ENXIO;
185 }
186
187 EXPORT_SYMBOL(snd_device_register);
188
189 /*
190  * register all the devices on the card.
191  * called from init.c
192  */
193 int snd_device_register_all(struct snd_card *card)
194 {
195         struct list_head *list;
196         struct snd_device *dev;
197         int err;
198         
199         snd_assert(card != NULL, return -ENXIO);
200         list_for_each(list, &card->devices) {
201                 dev = snd_device(list);
202                 if (dev->state == SNDRV_DEV_BUILD && dev->ops->dev_register) {
203                         if ((err = dev->ops->dev_register(dev)) < 0)
204                                 return err;
205                         dev->state = SNDRV_DEV_REGISTERED;
206                 }
207         }
208         return 0;
209 }
210
211 /*
212  * disconnect all the devices on the card.
213  * called from init.c
214  */
215 int snd_device_disconnect_all(struct snd_card *card)
216 {
217         struct snd_device *dev;
218         struct list_head *list;
219         int err = 0;
220
221         snd_assert(card != NULL, return -ENXIO);
222         list_for_each(list, &card->devices) {
223                 dev = snd_device(list);
224                 if (snd_device_disconnect(card, dev->device_data) < 0)
225                         err = -ENXIO;
226         }
227         return err;
228 }
229
230 /*
231  * release all the devices on the card.
232  * called from init.c
233  */
234 int snd_device_free_all(struct snd_card *card, snd_device_cmd_t cmd)
235 {
236         struct snd_device *dev;
237         struct list_head *list;
238         int err;
239         unsigned int range_low, range_high;
240
241         snd_assert(card != NULL, return -ENXIO);
242         range_low = cmd * SNDRV_DEV_TYPE_RANGE_SIZE;
243         range_high = range_low + SNDRV_DEV_TYPE_RANGE_SIZE - 1;
244       __again:
245         list_for_each(list, &card->devices) {
246                 dev = snd_device(list);         
247                 if (dev->type >= range_low && dev->type <= range_high) {
248                         if ((err = snd_device_free(card, dev->device_data)) < 0)
249                                 return err;
250                         goto __again;
251                 }
252         }
253         return 0;
254 }