diff options
Diffstat (limited to 'alsa_utils/alsa_device_proxy.c')
| -rw-r--r-- | alsa_utils/alsa_device_proxy.c | 159 |
1 files changed, 159 insertions, 0 deletions
diff --git a/alsa_utils/alsa_device_proxy.c b/alsa_utils/alsa_device_proxy.c new file mode 100644 index 00000000..d2d8b6f1 --- /dev/null +++ b/alsa_utils/alsa_device_proxy.c @@ -0,0 +1,159 @@ +/* + * Copyright (C) 2014 The Android Open Source Project + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#define LOG_TAG "alsa_device_proxy" +/*#define LOG_NDEBUG 0*/ +/*#define LOG_PCM_PARAMS 0*/ + +#include <log/log.h> + +#include <errno.h> + +#include "include/alsa_device_proxy.h" + +#include "include/alsa_logging.h" + +#define DEFAULT_PERIOD_SIZE 1024 +#define DEFAULT_PERIOD_COUNT 2 + +void proxy_prepare(alsa_device_proxy * proxy, alsa_device_profile* profile, + struct pcm_config * config) +{ + ALOGV("proxy_prepare(c:%d, d:%d)", profile->card, profile->device); + + proxy->profile = profile; + +#ifdef LOG_PCM_PARAMS + log_pcm_config(config, "proxy_setup()"); +#endif + + proxy->alsa_config.format = + config->format != PCM_FORMAT_INVALID && profile_is_format_valid(profile, config->format) + ? config->format : profile->default_config.format; + proxy->alsa_config.rate = + config->rate != 0 && profile_is_sample_rate_valid(profile, config->rate) + ? config->rate : profile->default_config.rate; + proxy->alsa_config.channels = + config->channels != 0 && profile_is_channel_count_valid(profile, config->channels) + ? config->channels : profile->default_config.channels; + + proxy->alsa_config.period_count = profile->default_config.period_count; + proxy->alsa_config.period_size = + profile_get_period_size(proxy->profile, proxy->alsa_config.rate); + + // Hack for USB accessory audio. + // Here we set the correct value for period_count if tinyalsa fails to get it from the + // f_audio_source driver. + if (proxy->alsa_config.period_count == 0) { + proxy->alsa_config.period_count = 4; + } + + proxy->pcm = NULL; +} + +int proxy_open(alsa_device_proxy * proxy) +{ + alsa_device_profile* profile = proxy->profile; + ALOGV("proxy_open(card:%d device:%d %s)", profile->card, profile->device, + profile->direction == PCM_OUT ? "PCM_OUT" : "PCM_IN"); + + if (profile->card < 0 || profile->device < 0) { + return -EINVAL; + } + + proxy->pcm = pcm_open(profile->card, profile->device, profile->direction, &proxy->alsa_config); + if (proxy->pcm == NULL) { + return -ENOMEM; + } + + if (!pcm_is_ready(proxy->pcm)) { + ALOGE(" proxy_open() pcm_open() failed: %s", pcm_get_error(proxy->pcm)); +#if defined(LOG_PCM_PARAMS) + log_pcm_config(&proxy->alsa_config, "config"); +#endif + pcm_close(proxy->pcm); + proxy->pcm = NULL; + return -ENOMEM; + } + + return 0; +} + +void proxy_close(alsa_device_proxy * proxy) +{ + ALOGV("proxy_close() [pcm:%p]", proxy->pcm); + + if (proxy->pcm != NULL) { + pcm_close(proxy->pcm); + proxy->pcm = NULL; + } +} + +/* + * Sample Rate + */ +unsigned proxy_get_sample_rate(const alsa_device_proxy * proxy) +{ + return proxy->alsa_config.rate; +} + +/* + * Format + */ +enum pcm_format proxy_get_format(const alsa_device_proxy * proxy) +{ + return proxy->alsa_config.format; +} + +/* + * Channel Count + */ +unsigned proxy_get_channel_count(const alsa_device_proxy * proxy) +{ + return proxy->alsa_config.channels; +} + +/* + * Other + */ +unsigned int proxy_get_period_size(const alsa_device_proxy * proxy) +{ + return proxy->alsa_config.period_size; +} + +unsigned int proxy_get_period_count(const alsa_device_proxy * proxy) +{ + return proxy->alsa_config.period_count; +} + +unsigned proxy_get_latency(const alsa_device_proxy * proxy) +{ + return (proxy_get_period_size(proxy) * proxy_get_period_count(proxy) * 1000) + / proxy_get_sample_rate(proxy); +} + +/* + * I/O + */ +int proxy_write(const alsa_device_proxy * proxy, const void *data, unsigned int count) +{ + return pcm_write(proxy->pcm, data, count); +} + +int proxy_read(const alsa_device_proxy * proxy, void *data, unsigned int count) +{ + return pcm_read(proxy->pcm, data, count); +} |