1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
|
/*
* 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) {
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 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->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 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;
}
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 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;
}
|
