/* * 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. */ #ifndef ANDROID_SYSTEM_MEDIA_ALSA_UTILS_ALSA_DEVICE_PROXY_H #define ANDROID_SYSTEM_MEDIA_ALSA_UTILS_ALSA_DEVICE_PROXY_H #include <tinyalsa/asoundlib.h> #include "alsa_device_profile.h" typedef struct { const alsa_device_profile* profile; struct pcm_config alsa_config; struct pcm * pcm; size_t frame_size; /* valid after proxy_prepare(), the frame size in bytes */ uint64_t transferred; /* the total frames transferred, not cleared on standby */ } alsa_device_proxy; /* State */ int proxy_prepare(alsa_device_proxy * proxy, const alsa_device_profile * profile, struct pcm_config * config); int proxy_open(alsa_device_proxy * proxy); void proxy_close(alsa_device_proxy * proxy); int proxy_get_presentation_position(const alsa_device_proxy * proxy, uint64_t *frames, struct timespec *timestamp); /* Attributes */ unsigned proxy_get_sample_rate(const alsa_device_proxy * proxy); enum pcm_format proxy_get_format(const alsa_device_proxy * proxy); unsigned proxy_get_channel_count(const alsa_device_proxy * proxy); unsigned int proxy_get_period_size(const alsa_device_proxy * proxy); unsigned proxy_get_latency(const alsa_device_proxy * proxy); /* * Scans the provided list of sample rates and finds the first one that works. * * returns the index of the first rate for which the ALSA device can be opened. * return negative value if none work or an error occurs. */ int proxy_scan_rates(alsa_device_proxy * proxy, const unsigned sample_rates[]); /* I/O */ int proxy_write(alsa_device_proxy * proxy, const void *data, unsigned int count); int proxy_read(const alsa_device_proxy * proxy, void *data, unsigned int count); /* Debugging */ void proxy_dump(const alsa_device_proxy * proxy, int fd); #endif /* ANDROID_SYSTEM_MEDIA_ALSA_UTILS_ALSA_DEVICE_PROXY_H */