alsa_device_proxy.c revision c88e6ae584a5f7ea65ab6df89e381c2c7bf8e84e 
1/*
2 * Copyright (C) 2014 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#define LOG_TAG "alsa_device_proxy"
18/*#define LOG_NDEBUG 0*/
19/*#define LOG_PCM_PARAMS 0*/
20
21#include <log/log.h>
22
23#include "alsa_device_proxy.h"
24
25#include "logging.h"
26
27#define DEFAULT_PERIOD_SIZE     1024
28#define DEFAULT_PERIOD_COUNT    2
29
30//void proxy_init(alsa_device_proxy * proxy)
31//{
32//    proxy->profile = NULL;
33//
34//    proxy->alsa_config.format = DEFAULT_SAMPLE_FORMAT;
35//    proxy->alsa_config.rate = DEFAULT_SAMPLE_RATE;
36//    proxy->alsa_config.channels = DEFAULT_CHANNEL_COUNT;
37//
38//    proxy->alsa_config.period_size = DEFAULT_PERIOD_SIZE;
39//    proxy->alsa_config.period_count = DEFAULT_PERIOD_COUNT;
40//
41//    proxy->pcm = NULL;
42//}
43
44void proxy_prepare(alsa_device_proxy * proxy, alsa_device_profile* profile,
45                   struct pcm_config * config)
46{
47    ALOGV("proxy_prepare()");
48
49    proxy->profile = profile;
50
51#if LOG_PCM_PARAMS
52    log_pcm_config(config, "proxy_setup()");
53#endif
54
55    proxy->alsa_config.format =
56        config->format != PCM_FORMAT_INVALID && profile_is_format_valid(profile, config->format)
57            ? config->format : profile->default_config.format;
58    proxy->alsa_config.rate =
59        config->rate != 0 && profile_is_sample_rate_valid(profile, config->rate)
60            ? config->rate : profile->default_config.rate;
61    proxy->alsa_config.channels =
62        config->channels != 0 && profile_is_channel_count_valid(profile, config->channels)
63            ? config->channels : profile->default_config.channels;
64
65    proxy->alsa_config.period_count = profile->default_config.period_count;
66    proxy->alsa_config.period_size =
67            profile_get_period_size(proxy->profile, proxy->alsa_config.rate);
68
69    proxy->pcm = NULL;
70}
71
72int proxy_open(alsa_device_proxy * proxy)
73{
74    alsa_device_profile* profile = proxy->profile;
75
76    ALOGV("proxy_open(card:%d device:%d %s)", profile->card, profile->device,
77          profile->direction == PCM_OUT ? "PCM_OUT" : "PCM_IN");
78
79    proxy->pcm = pcm_open(profile->card, profile->device, profile->direction, &proxy->alsa_config);
80    if (proxy->pcm == NULL) {
81        return -ENOMEM;
82    }
83
84    if (!pcm_is_ready(proxy->pcm)) {
85        ALOGE("[%s] proxy_open() pcm_open() failed: %s", LOG_TAG, pcm_get_error(proxy->pcm));
86#ifdef LOG_PCM_PARAMS
87        log_pcm_config(&proxy->alsa_config, "config");
88#endif
89        pcm_close(proxy->pcm);
90        proxy->pcm = NULL;
91        return -ENOMEM;
92    }
93
94    return 0;
95}
96
97void proxy_close(alsa_device_proxy * proxy)
98{
99    pcm_close(proxy->pcm);
100    proxy->pcm = NULL;
101}
102
103/*
104 * Sample Rate
105 */
106unsigned proxy_get_sample_rate(const alsa_device_proxy * proxy)
107{
108    return proxy->alsa_config.rate;
109}
110
111/*
112 * Format
113 */
114enum pcm_format proxy_get_format(const alsa_device_proxy * proxy)
115{
116    return proxy->alsa_config.format;
117}
118
119/*
120 * Channel Count
121 */
122unsigned proxy_get_channel_count(const alsa_device_proxy * proxy)
123{
124    return proxy->alsa_config.channels;
125}
126
127/*
128 * Other
129 */
130unsigned int proxy_get_period_size(const alsa_device_proxy * proxy)
131{
132    return proxy->alsa_config.period_size;
133}
134
135unsigned int proxy_get_period_count(const alsa_device_proxy * proxy)
136{
137    return proxy->alsa_config.period_count;
138}
139
140unsigned proxy_get_latency(const alsa_device_proxy * proxy)
141{
142    return (proxy_get_period_size(proxy) * proxy_get_period_count(proxy) * 1000)
143               / proxy_get_sample_rate(proxy);
144}
145
146/*
147 * I/O
148 */
149int proxy_write(const alsa_device_proxy * proxy, const void *data, unsigned int count)
150{
151    return pcm_write(proxy->pcm, data, count);
152}
153
154int proxy_read(const alsa_device_proxy * proxy, void *data, unsigned int count)
155{
156    return pcm_read(proxy->pcm, data, count);
157}
158