asoundlib.h revision 4c0f7e8e52f77fb914c5628e7ef5a974f70aab97
1/* asoundlib.h 2** 3** Copyright 2011, The Android Open Source Project 4** 5** Redistribution and use in source and binary forms, with or without 6** modification, are permitted provided that the following conditions are 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 copyright 10** notice, this list of conditions and the following disclaimer in the 11** documentation and/or other materials provided with the distribution. 12** * Neither the name of The Android Open Source Project nor the names of 13** its contributors may be used to endorse or promote products derived 14** from this software without specific prior written permission. 15** 16** THIS SOFTWARE IS PROVIDED BY The Android Open Source Project ``AS IS'' AND 17** ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19** ARE DISCLAIMED. IN NO EVENT SHALL The Android Open Source Project BE LIABLE 20** FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21** DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 22** SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 23** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25** OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH 26** DAMAGE. 27*/ 28 29#ifndef ASOUNDLIB_H 30#define ASOUNDLIB_H 31 32#include <sys/time.h> 33 34#if defined(__cplusplus) 35extern "C" { 36#endif 37 38/* 39 * PCM API 40 */ 41 42struct pcm; 43 44#define PCM_OUT 0x00000000 45#define PCM_IN 0x10000000 46#define PCM_MMAP 0x00000001 47#define PCM_NOIRQ 0x00000002 48 49/* PCM runtime states */ 50#define PCM_STATE_OPEN 0 51#define PCM_STATE_SETUP 1 52#define PCM_STATE_PREPARED 2 53#define PCM_STATE_RUNNING 3 54#define PCM_STATE_XRUN 4 55#define PCM_STATE_DRAINING 5 56#define PCM_STATE_PAUSED 6 57#define PCM_STATE_SUSPENDED 7 58#define PCM_STATE_DISCONNECTED 8 59 60/* Bit formats */ 61enum pcm_format { 62 PCM_FORMAT_S16_LE = 0, 63 PCM_FORMAT_S32_LE, 64 65 PCM_FORMAT_MAX, 66}; 67 68/* Configuration for a stream */ 69struct pcm_config { 70 unsigned int channels; 71 unsigned int rate; 72 unsigned int period_size; 73 unsigned int period_count; 74 enum pcm_format format; 75 76 /* Values to use for the ALSA start, stop and silence thresholds. Setting 77 * any one of these values to 0 will cause the default tinyalsa values to be 78 * used instead. Tinyalsa defaults are as follows. 79 * 80 * start_threshold : period_count * period_size 81 * stop_threshold : period_count * period_size 82 * silence_threshold : 0 83 */ 84 unsigned int start_threshold; 85 unsigned int stop_threshold; 86 unsigned int silence_threshold; 87 88 /* Minimum number of frames available before pcm_mmap_write() will actually 89 * write into the kernel buffer. Only used if the stream is opened in mmap mode 90 * (pcm_open() called with PCM_MMAP flag set). Use 0 for default. 91 */ 92 int avail_min; 93}; 94 95/* Mixer control types */ 96enum mixer_ctl_type { 97 MIXER_CTL_TYPE_BOOL, 98 MIXER_CTL_TYPE_INT, 99 MIXER_CTL_TYPE_ENUM, 100 MIXER_CTL_TYPE_BYTE, 101 MIXER_CTL_TYPE_IEC958, 102 MIXER_CTL_TYPE_INT64, 103 MIXER_CTL_TYPE_UNKNOWN, 104 105 MIXER_CTL_TYPE_MAX, 106}; 107 108/* Open and close a stream */ 109struct pcm *pcm_open(unsigned int card, unsigned int device, 110 unsigned int flags, struct pcm_config *config); 111int pcm_close(struct pcm *pcm); 112int pcm_is_ready(struct pcm *pcm); 113 114/* Set and get config */ 115int pcm_get_config(struct pcm *pcm, struct pcm_config *config); 116int pcm_set_config(struct pcm *pcm, struct pcm_config *config); 117 118/* Returns a human readable reason for the last error */ 119const char *pcm_get_error(struct pcm *pcm); 120 121/* Returns the buffer size (int frames) that should be used for pcm_write. */ 122unsigned int pcm_get_buffer_size(struct pcm *pcm); 123unsigned int pcm_frames_to_bytes(struct pcm *pcm, unsigned int frames); 124unsigned int pcm_bytes_to_frames(struct pcm *pcm, unsigned int bytes); 125 126/* Returns the pcm latency in ms */ 127unsigned int pcm_get_latency(struct pcm *pcm); 128 129/* Returns available frames in pcm buffer and corresponding time stamp. 130 * For an input stream, frames available are frames ready for the 131 * application to read. 132 * For an output stream, frames available are the number of empty frames available 133 * for the application to write. 134 */ 135int pcm_get_htimestamp(struct pcm *pcm, unsigned int *avail, 136 struct timespec *tstamp); 137 138/* Write data to the fifo. 139 * Will start playback on the first write or on a write that 140 * occurs after a fifo underrun. 141 */ 142int pcm_write(struct pcm *pcm, void *data, unsigned int count); 143int pcm_read(struct pcm *pcm, void *data, unsigned int count); 144 145/* 146 * mmap() support. 147 */ 148int pcm_mmap_write(struct pcm *pcm, void *data, unsigned int count); 149int pcm_mmap_begin(struct pcm *pcm, void **areas, unsigned int *offset, 150 unsigned int *frames); 151int pcm_mmap_commit(struct pcm *pcm, unsigned int offset, unsigned int frames); 152 153/* Start and stop a PCM channel that doesn't transfer data */ 154int pcm_start(struct pcm *pcm); 155int pcm_stop(struct pcm *pcm); 156 157/* Change avail_min after the stream has been opened with no need to stop the stream. 158 * Only accepted if opened with PCM_MMAP and PCM_NOIRQ flags 159 */ 160int pcm_set_avail_min(struct pcm *pcm, int avail_min); 161 162/* 163 * MIXER API 164 */ 165 166struct mixer; 167struct mixer_ctl; 168 169/* Open and close a mixer */ 170struct mixer *mixer_open(unsigned int card); 171void mixer_close(struct mixer *mixer); 172 173/* Obtain mixer controls */ 174unsigned int mixer_get_num_ctls(struct mixer *mixer); 175struct mixer_ctl *mixer_get_ctl(struct mixer *mixer, unsigned int id); 176struct mixer_ctl *mixer_get_ctl_by_name(struct mixer *mixer, const char *name); 177 178/* Get info about mixer controls */ 179int mixer_ctl_get_name(struct mixer_ctl *ctl, char *name, unsigned int size); 180enum mixer_ctl_type mixer_ctl_get_type(struct mixer_ctl *ctl); 181const char *mixer_ctl_get_type_string(struct mixer_ctl *ctl); 182unsigned int mixer_ctl_get_num_values(struct mixer_ctl *ctl); 183unsigned int mixer_ctl_get_num_enums(struct mixer_ctl *ctl); 184int mixer_ctl_get_enum_string(struct mixer_ctl *ctl, unsigned int enum_id, 185 char *string, unsigned int size); 186 187/* Set and get mixer controls */ 188int mixer_ctl_get_percent(struct mixer_ctl *ctl, unsigned int id); 189int mixer_ctl_set_percent(struct mixer_ctl *ctl, unsigned int id, int percent); 190 191int mixer_ctl_get_value(struct mixer_ctl *ctl, unsigned int id); 192int mixer_ctl_set_value(struct mixer_ctl *ctl, unsigned int id, int value); 193int mixer_ctl_set_enum_by_string(struct mixer_ctl *ctl, const char *string); 194 195/* Determe range of integer mixer controls */ 196int mixer_ctl_get_range_min(struct mixer_ctl *ctl); 197int mixer_ctl_get_range_max(struct mixer_ctl *ctl); 198 199#if defined(__cplusplus) 200} /* extern "C" */ 201#endif 202 203#endif 204