| /* |
| * 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 |
| |
| #define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0])) |
| |
| static const unsigned format_byte_size_map[] = { |
| 2, /* PCM_FORMAT_S16_LE */ |
| 4, /* PCM_FORMAT_S32_LE */ |
| 1, /* PCM_FORMAT_S8 */ |
| 4, /* PCM_FORMAT_S24_LE */ |
| 3, /* PCM_FORMAT_S24_3LE */ |
| }; |
| |
| 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; |
| // config format should be checked earlier against profile. |
| if (config->format >= 0 && (size_t)config->format < ARRAY_SIZE(format_byte_size_map)) { |
| proxy->frame_size = format_byte_size_map[config->format] * proxy->alsa_config.channels; |
| } else { |
| proxy->frame_size = 1; |
| } |
| } |
| |
| 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 | PCM_MONOTONIC, &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); |
| } |
| |
| int proxy_get_presentation_position(const alsa_device_proxy * proxy, |
| uint64_t *frames, struct timespec *timestamp) |
| { |
| int ret = -EPERM; // -1 |
| unsigned int avail; |
| if (proxy->pcm != NULL |
| && pcm_get_htimestamp(proxy->pcm, &avail, timestamp) == 0) { |
| const size_t kernel_buffer_size = |
| proxy->alsa_config.period_size * proxy->alsa_config.period_count; |
| if (avail > kernel_buffer_size) { |
| ALOGE("available frames(%u) > buffer size(%zu)", avail, kernel_buffer_size); |
| } else { |
| int64_t signed_frames = proxy->transferred - kernel_buffer_size + avail; |
| // It is possible to compensate for additional driver and device delay |
| // by changing signed_frames. Example: |
| // signed_frames -= 20 /* ms */ * proxy->alsa_config.rate / 1000; |
| if (signed_frames >= 0) { |
| *frames = signed_frames; |
| ret = 0; |
| } |
| } |
| } |
| return ret; |
| } |
| |
| /* |
| * I/O |
| */ |
| int proxy_write(alsa_device_proxy * proxy, const void *data, unsigned int count) |
| { |
| int ret = pcm_write(proxy->pcm, data, count); |
| if (ret == 0) { |
| proxy->transferred += count / proxy->frame_size; |
| } |
| return ret; |
| } |
| |
| int proxy_read(const alsa_device_proxy * proxy, void *data, unsigned int count) |
| { |
| return pcm_read(proxy->pcm, data, count); |
| } |