1 /* snd_utils.h
2 ** Copyright (c) 2019, The Linux Foundation.
3 **
4 ** Redistribution and use in source and binary forms, with or without
5 ** modification, are permitted provided that the following conditions are
6 ** met:
7 **   * Redistributions of source code must retain the above copyright
8 **     notice, this list of conditions and the following disclaimer.
9 **   * Redistributions in binary form must reproduce the above
10 **     copyright notice, this list of conditions and the following
11 **     disclaimer in the documentation and/or other materials provided
12 **     with the distribution.
13 **   * Neither the name of The Linux Foundation nor the names of its
14 **     contributors may be used to endorse or promote products derived
15 **     from this software without specific prior written permission.
16 **
17 ** THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
18 ** WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
19 ** MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT
20 ** ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
21 ** BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
22 ** CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
23 ** SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
24 ** BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
25 ** WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
26 ** OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
27 ** IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 **/
29 
30 #ifndef TINYALSA_SRC_SND_CARD_UTILS_H
31 #define TINYALSA_SRC_SND_CARD_UTILS_H
32 
33 #include <tinyalsa/plugin.h>
34 
35 #include <dlfcn.h>
36 
37 /** Encapsulates the pcm device definition from
38  * the sound card definition configuration file.
39  */
40 struct snd_node {
41     /** Pointer the card definition */
42     void *card_node;
43     /** Pointer to device definition, either PCM or MIXER device */
44     void *dev_node;
45     /** Pointer to the sound card parser library */
46     void *dl_hdl;
47     /** A pointer to the operations structure. */
48     const struct snd_node_ops* ops;
49 };
50 
51 enum snd_node_type {
52     SND_NODE_TYPE_HW = 0,
53     SND_NODE_TYPE_PLUGIN,
54     SND_NODE_TYPE_INVALID,
55 };
56 
57 enum {
58   NODE_PCM,
59   NODE_MIXER
60 };
61 
62 struct snd_node *snd_utils_open_pcm(unsigned int card, unsigned int device);
63 
64 struct snd_node *snd_utils_open_mixer(unsigned int card);
65 
66 void snd_utils_close_dev_node(struct snd_node *node);
67 
68 enum snd_node_type snd_utils_get_node_type(struct snd_node *node);
69 
70 int snd_utils_get_int(struct snd_node *node, const char *prop, int *val);
71 
72 int snd_utils_get_str(struct snd_node *node, const char *prop, char **val);
73 
74 #endif /* end of TINYALSA_SRC_SND_CARD_UTILS_H */
75