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#define PCM_NORESTART 0x00000004 /* PCM_NORESTART - when set, calls to 49 * pcm_write for a playback stream will not 50 * attempt to restart the stream in the case 51 * of an underflow, but will return -EPIPE 52 * instead. After the first -EPIPE error, the 53 * stream is considered to be stopped, and a 54 * second call to pcm_write will attempt to 55 * restart the stream. 56 */ 57 58/* PCM runtime states */ 59#define PCM_STATE_OPEN 0 60#define PCM_STATE_SETUP 1 61#define PCM_STATE_PREPARED 2 62#define PCM_STATE_RUNNING 3 63#define PCM_STATE_XRUN 4 64#define PCM_STATE_DRAINING 5 65#define PCM_STATE_PAUSED 6 66#define PCM_STATE_SUSPENDED 7 67#define PCM_STATE_DISCONNECTED 8 68 69/* Bit formats */ 70enum pcm_format { 71 PCM_FORMAT_S16_LE = 0, 72 PCM_FORMAT_S32_LE, 73 74 PCM_FORMAT_MAX, 75}; 76 77/* Configuration for a stream */ 78struct pcm_config { 79 unsigned int channels; 80 unsigned int rate; 81 unsigned int period_size; 82 unsigned int period_count; 83 enum pcm_format format; 84 85 /* Values to use for the ALSA start, stop and silence thresholds. Setting 86 * any one of these values to 0 will cause the default tinyalsa values to be 87 * used instead. Tinyalsa defaults are as follows. 88 * 89 * start_threshold : period_count * period_size 90 * stop_threshold : period_count * period_size 91 * silence_threshold : 0 92 */ 93 unsigned int start_threshold; 94 unsigned int stop_threshold; 95 unsigned int silence_threshold; 96 97 /* Minimum number of frames available before pcm_mmap_write() will actually 98 * write into the kernel buffer. Only used if the stream is opened in mmap mode 99 * (pcm_open() called with PCM_MMAP flag set). Use 0 for default. 100 */ 101 int avail_min; 102}; 103 104/* Mixer control types */ 105enum mixer_ctl_type { 106 MIXER_CTL_TYPE_BOOL, 107 MIXER_CTL_TYPE_INT, 108 MIXER_CTL_TYPE_ENUM, 109 MIXER_CTL_TYPE_BYTE, 110 MIXER_CTL_TYPE_IEC958, 111 MIXER_CTL_TYPE_INT64, 112 MIXER_CTL_TYPE_UNKNOWN, 113 114 MIXER_CTL_TYPE_MAX, 115}; 116 117/* Open and close a stream */ 118struct pcm *pcm_open(unsigned int card, unsigned int device, 119 unsigned int flags, struct pcm_config *config); 120int pcm_close(struct pcm *pcm); 121int pcm_is_ready(struct pcm *pcm); 122 123/* Set and get config */ 124int pcm_get_config(struct pcm *pcm, struct pcm_config *config); 125int pcm_set_config(struct pcm *pcm, struct pcm_config *config); 126 127/* Returns a human readable reason for the last error */ 128const char *pcm_get_error(struct pcm *pcm); 129 130/* Returns the buffer size (int frames) that should be used for pcm_write. */ 131unsigned int pcm_get_buffer_size(struct pcm *pcm); 132unsigned int pcm_frames_to_bytes(struct pcm *pcm, unsigned int frames); 133unsigned int pcm_bytes_to_frames(struct pcm *pcm, unsigned int bytes); 134 135/* Returns the pcm latency in ms */ 136unsigned int pcm_get_latency(struct pcm *pcm); 137 138/* Returns available frames in pcm buffer and corresponding time stamp. 139 * For an input stream, frames available are frames ready for the 140 * application to read. 141 * For an output stream, frames available are the number of empty frames available 142 * for the application to write. 143 */ 144int pcm_get_htimestamp(struct pcm *pcm, unsigned int *avail, 145 struct timespec *tstamp); 146 147/* Write data to the fifo. 148 * Will start playback on the first write or on a write that 149 * occurs after a fifo underrun. 150 */ 151int pcm_write(struct pcm *pcm, const void *data, unsigned int count); 152int pcm_read(struct pcm *pcm, void *data, unsigned int count); 153 154/* 155 * mmap() support. 156 */ 157int pcm_mmap_write(struct pcm *pcm, const void *data, unsigned int count); 158int pcm_mmap_begin(struct pcm *pcm, void **areas, unsigned int *offset, 159 unsigned int *frames); 160int pcm_mmap_commit(struct pcm *pcm, unsigned int offset, unsigned int frames); 161 162/* Start and stop a PCM channel that doesn't transfer data */ 163int pcm_start(struct pcm *pcm); 164int pcm_stop(struct pcm *pcm); 165 166/* Change avail_min after the stream has been opened with no need to stop the stream. 167 * Only accepted if opened with PCM_MMAP and PCM_NOIRQ flags 168 */ 169int pcm_set_avail_min(struct pcm *pcm, int avail_min); 170 171/* 172 * MIXER API 173 */ 174 175struct mixer; 176struct mixer_ctl; 177 178/* Open and close a mixer */ 179struct mixer *mixer_open(unsigned int card); 180void mixer_close(struct mixer *mixer); 181 182/* Obtain mixer controls */ 183unsigned int mixer_get_num_ctls(struct mixer *mixer); 184struct mixer_ctl *mixer_get_ctl(struct mixer *mixer, unsigned int id); 185struct mixer_ctl *mixer_get_ctl_by_name(struct mixer *mixer, const char *name); 186 187/* Get info about mixer controls */ 188const char *mixer_ctl_get_name(struct mixer_ctl *ctl); 189enum mixer_ctl_type mixer_ctl_get_type(struct mixer_ctl *ctl); 190const char *mixer_ctl_get_type_string(struct mixer_ctl *ctl); 191unsigned int mixer_ctl_get_num_values(struct mixer_ctl *ctl); 192unsigned int mixer_ctl_get_num_enums(struct mixer_ctl *ctl); 193const char *mixer_ctl_get_enum_string(struct mixer_ctl *ctl, 194 unsigned int enum_id); 195 196/* Set and get mixer controls */ 197int mixer_ctl_get_percent(struct mixer_ctl *ctl, unsigned int id); 198int mixer_ctl_set_percent(struct mixer_ctl *ctl, unsigned int id, int percent); 199 200int mixer_ctl_get_value(struct mixer_ctl *ctl, unsigned int id); 201int mixer_ctl_set_value(struct mixer_ctl *ctl, unsigned int id, int value); 202int mixer_ctl_set_enum_by_string(struct mixer_ctl *ctl, const char *string); 203 204/* Determe range of integer mixer controls */ 205int mixer_ctl_get_range_min(struct mixer_ctl *ctl); 206int mixer_ctl_get_range_max(struct mixer_ctl *ctl); 207 208#if defined(__cplusplus) 209} /* extern "C" */ 210#endif 211 212#endif 213