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 #include <stddef.h> 34 35 #if defined(__cplusplus) 36 extern "C" { 37 #endif 38 39 /* 40 * PCM API 41 */ 42 43 struct pcm; 44 45 #define PCM_OUT 0x00000000 46 #define PCM_IN 0x10000000 47 #define PCM_MMAP 0x00000001 48 #define PCM_NOIRQ 0x00000002 49 #define PCM_NORESTART 0x00000004 /* PCM_NORESTART - when set, calls to 50 * pcm_write for a playback stream will not 51 * attempt to restart the stream in the case 52 * of an underflow, but will return -EPIPE 53 * instead. After the first -EPIPE error, the 54 * stream is considered to be stopped, and a 55 * second call to pcm_write will attempt to 56 * restart the stream. 57 */ 58 #define PCM_MONOTONIC 0x00000008 /* see pcm_get_htimestamp */ 59 60 /* PCM runtime states */ 61 #define PCM_STATE_OPEN 0 62 #define PCM_STATE_SETUP 1 63 #define PCM_STATE_PREPARED 2 64 #define PCM_STATE_RUNNING 3 65 #define PCM_STATE_XRUN 4 66 #define PCM_STATE_DRAINING 5 67 #define PCM_STATE_PAUSED 6 68 #define PCM_STATE_SUSPENDED 7 69 #define PCM_STATE_DISCONNECTED 8 70 71 /* Bit formats */ 72 enum pcm_format { 73 PCM_FORMAT_S16_LE = 0, 74 PCM_FORMAT_S32_LE, 75 PCM_FORMAT_S8, 76 PCM_FORMAT_S24_LE, 77 78 PCM_FORMAT_MAX, 79 }; 80 81 /* Configuration for a stream */ 82 struct pcm_config { 83 unsigned int channels; 84 unsigned int rate; 85 unsigned int period_size; 86 unsigned int period_count; 87 enum pcm_format format; 88 89 /* Values to use for the ALSA start, stop and silence thresholds. Setting 90 * any one of these values to 0 will cause the default tinyalsa values to be 91 * used instead. Tinyalsa defaults are as follows. 92 * 93 * start_threshold : period_count * period_size 94 * stop_threshold : period_count * period_size 95 * silence_threshold : 0 96 */ 97 unsigned int start_threshold; 98 unsigned int stop_threshold; 99 unsigned int silence_threshold; 100 101 /* Minimum number of frames available before pcm_mmap_write() will actually 102 * write into the kernel buffer. Only used if the stream is opened in mmap mode 103 * (pcm_open() called with PCM_MMAP flag set). Use 0 for default. 104 */ 105 int avail_min; 106 }; 107 108 /* PCM parameters */ 109 enum pcm_param 110 { 111 PCM_PARAM_SAMPLE_BITS, 112 PCM_PARAM_FRAME_BITS, 113 PCM_PARAM_CHANNELS, 114 PCM_PARAM_RATE, 115 PCM_PARAM_PERIOD_TIME, 116 PCM_PARAM_PERIOD_SIZE, 117 PCM_PARAM_PERIOD_BYTES, 118 PCM_PARAM_PERIODS, 119 PCM_PARAM_BUFFER_TIME, 120 PCM_PARAM_BUFFER_SIZE, 121 PCM_PARAM_BUFFER_BYTES, 122 PCM_PARAM_TICK_TIME, 123 }; 124 125 /* Mixer control types */ 126 enum mixer_ctl_type { 127 MIXER_CTL_TYPE_BOOL, 128 MIXER_CTL_TYPE_INT, 129 MIXER_CTL_TYPE_ENUM, 130 MIXER_CTL_TYPE_BYTE, 131 MIXER_CTL_TYPE_IEC958, 132 MIXER_CTL_TYPE_INT64, 133 MIXER_CTL_TYPE_UNKNOWN, 134 135 MIXER_CTL_TYPE_MAX, 136 }; 137 138 /* Open and close a stream */ 139 struct pcm *pcm_open(unsigned int card, unsigned int device, 140 unsigned int flags, struct pcm_config *config); 141 int pcm_close(struct pcm *pcm); 142 int pcm_is_ready(struct pcm *pcm); 143 144 /* Obtain the parameters for a PCM */ 145 struct pcm_params *pcm_params_get(unsigned int card, unsigned int device, 146 unsigned int flags); 147 void pcm_params_free(struct pcm_params *pcm_params); 148 unsigned int pcm_params_get_min(struct pcm_params *pcm_params, 149 enum pcm_param param); 150 unsigned int pcm_params_get_max(struct pcm_params *pcm_params, 151 enum pcm_param param); 152 153 /* Set and get config */ 154 int pcm_get_config(struct pcm *pcm, struct pcm_config *config); 155 int pcm_set_config(struct pcm *pcm, struct pcm_config *config); 156 157 /* Returns a human readable reason for the last error */ 158 const char *pcm_get_error(struct pcm *pcm); 159 160 /* Returns the sample size in bits for a PCM format. 161 * As with ALSA formats, this is the storage size for the format, whereas the 162 * format represents the number of significant bits. For example, 163 * PCM_FORMAT_S24_LE uses 32 bits of storage. 164 */ 165 unsigned int pcm_format_to_bits(enum pcm_format format); 166 167 /* Returns the buffer size (int frames) that should be used for pcm_write. */ 168 unsigned int pcm_get_buffer_size(struct pcm *pcm); 169 unsigned int pcm_frames_to_bytes(struct pcm *pcm, unsigned int frames); 170 unsigned int pcm_bytes_to_frames(struct pcm *pcm, unsigned int bytes); 171 172 /* Returns the pcm latency in ms */ 173 unsigned int pcm_get_latency(struct pcm *pcm); 174 175 /* Returns available frames in pcm buffer and corresponding time stamp. 176 * The clock is CLOCK_MONOTONIC if flag PCM_MONOTONIC was specified in pcm_open, 177 * otherwise the clock is CLOCK_REALTIME. 178 * For an input stream, frames available are frames ready for the 179 * application to read. 180 * For an output stream, frames available are the number of empty frames available 181 * for the application to write. 182 */ 183 int pcm_get_htimestamp(struct pcm *pcm, unsigned int *avail, 184 struct timespec *tstamp); 185 186 /* Write data to the fifo. 187 * Will start playback on the first write or on a write that 188 * occurs after a fifo underrun. 189 */ 190 int pcm_write(struct pcm *pcm, const void *data, unsigned int count); 191 int pcm_read(struct pcm *pcm, void *data, unsigned int count); 192 193 /* 194 * mmap() support. 195 */ 196 int pcm_mmap_write(struct pcm *pcm, const void *data, unsigned int count); 197 int pcm_mmap_read(struct pcm *pcm, void *data, unsigned int count); 198 int pcm_mmap_begin(struct pcm *pcm, void **areas, unsigned int *offset, 199 unsigned int *frames); 200 int pcm_mmap_commit(struct pcm *pcm, unsigned int offset, unsigned int frames); 201 202 /* Start and stop a PCM channel that doesn't transfer data */ 203 int pcm_start(struct pcm *pcm); 204 int pcm_stop(struct pcm *pcm); 205 206 /* Interrupt driven API */ 207 int pcm_wait(struct pcm *pcm, int timeout); 208 209 /* Change avail_min after the stream has been opened with no need to stop the stream. 210 * Only accepted if opened with PCM_MMAP and PCM_NOIRQ flags 211 */ 212 int pcm_set_avail_min(struct pcm *pcm, int avail_min); 213 214 /* 215 * MIXER API 216 */ 217 218 struct mixer; 219 struct mixer_ctl; 220 221 /* Open and close a mixer */ 222 struct mixer *mixer_open(unsigned int card); 223 void mixer_close(struct mixer *mixer); 224 225 /* Get info about a mixer */ 226 const char *mixer_get_name(struct mixer *mixer); 227 228 /* Obtain mixer controls */ 229 unsigned int mixer_get_num_ctls(struct mixer *mixer); 230 struct mixer_ctl *mixer_get_ctl(struct mixer *mixer, unsigned int id); 231 struct mixer_ctl *mixer_get_ctl_by_name(struct mixer *mixer, const char *name); 232 233 /* Get info about mixer controls */ 234 const char *mixer_ctl_get_name(struct mixer_ctl *ctl); 235 enum mixer_ctl_type mixer_ctl_get_type(struct mixer_ctl *ctl); 236 const char *mixer_ctl_get_type_string(struct mixer_ctl *ctl); 237 unsigned int mixer_ctl_get_num_values(struct mixer_ctl *ctl); 238 unsigned int mixer_ctl_get_num_enums(struct mixer_ctl *ctl); 239 const char *mixer_ctl_get_enum_string(struct mixer_ctl *ctl, 240 unsigned int enum_id); 241 242 /* Some sound cards update their controls due to external events, 243 * such as HDMI EDID byte data changing when an HDMI cable is 244 * connected. This API allows the count of elements to be updated. 245 */ 246 void mixer_ctl_update(struct mixer_ctl *ctl); 247 248 /* Set and get mixer controls */ 249 int mixer_ctl_get_percent(struct mixer_ctl *ctl, unsigned int id); 250 int mixer_ctl_set_percent(struct mixer_ctl *ctl, unsigned int id, int percent); 251 252 int mixer_ctl_get_value(struct mixer_ctl *ctl, unsigned int id); 253 int mixer_ctl_get_array(struct mixer_ctl *ctl, void *array, size_t count); 254 int mixer_ctl_set_value(struct mixer_ctl *ctl, unsigned int id, int value); 255 int mixer_ctl_set_array(struct mixer_ctl *ctl, const void *array, size_t count); 256 int mixer_ctl_set_enum_by_string(struct mixer_ctl *ctl, const char *string); 257 258 /* Determe range of integer mixer controls */ 259 int mixer_ctl_get_range_min(struct mixer_ctl *ctl); 260 int mixer_ctl_get_range_max(struct mixer_ctl *ctl); 261 262 #if defined(__cplusplus) 263 } /* extern "C" */ 264 #endif 265 266 #endif 267