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_INVALID = -1, 74 PCM_FORMAT_S16_LE = 0, /* 16-bit signed */ 75 PCM_FORMAT_S32_LE, /* 32-bit signed */ 76 PCM_FORMAT_S8, /* 8-bit signed */ 77 PCM_FORMAT_S24_LE, /* 24-bits in 4-bytes */ 78 PCM_FORMAT_S24_3LE, /* 24-bits in 3-bytes */ 79 80 PCM_FORMAT_MAX, 81 }; 82 83 /* Bitmask has 256 bits (32 bytes) in asound.h */ 84 struct pcm_mask { 85 unsigned int bits[32 / sizeof(unsigned int)]; 86 }; 87 88 /* Configuration for a stream */ 89 struct pcm_config { 90 unsigned int channels; 91 unsigned int rate; 92 unsigned int period_size; 93 unsigned int period_count; 94 enum pcm_format format; 95 96 /* Values to use for the ALSA start, stop and silence thresholds. Setting 97 * any one of these values to 0 will cause the default tinyalsa values to be 98 * used instead. Tinyalsa defaults are as follows. 99 * 100 * start_threshold : period_count * period_size 101 * stop_threshold : period_count * period_size 102 * silence_threshold : 0 103 */ 104 unsigned int start_threshold; 105 unsigned int stop_threshold; 106 unsigned int silence_threshold; 107 108 /* Minimum number of frames available before pcm_mmap_write() will actually 109 * write into the kernel buffer. Only used if the stream is opened in mmap mode 110 * (pcm_open() called with PCM_MMAP flag set). Use 0 for default. 111 */ 112 int avail_min; 113 }; 114 115 /* PCM parameters */ 116 enum pcm_param 117 { 118 /* mask parameters */ 119 PCM_PARAM_ACCESS, 120 PCM_PARAM_FORMAT, 121 PCM_PARAM_SUBFORMAT, 122 /* interval parameters */ 123 PCM_PARAM_SAMPLE_BITS, 124 PCM_PARAM_FRAME_BITS, 125 PCM_PARAM_CHANNELS, 126 PCM_PARAM_RATE, 127 PCM_PARAM_PERIOD_TIME, 128 PCM_PARAM_PERIOD_SIZE, 129 PCM_PARAM_PERIOD_BYTES, 130 PCM_PARAM_PERIODS, 131 PCM_PARAM_BUFFER_TIME, 132 PCM_PARAM_BUFFER_SIZE, 133 PCM_PARAM_BUFFER_BYTES, 134 PCM_PARAM_TICK_TIME, 135 }; 136 137 /* Mixer control types */ 138 enum mixer_ctl_type { 139 MIXER_CTL_TYPE_BOOL, 140 MIXER_CTL_TYPE_INT, 141 MIXER_CTL_TYPE_ENUM, 142 MIXER_CTL_TYPE_BYTE, 143 MIXER_CTL_TYPE_IEC958, 144 MIXER_CTL_TYPE_INT64, 145 MIXER_CTL_TYPE_UNKNOWN, 146 147 MIXER_CTL_TYPE_MAX, 148 }; 149 150 /* Open and close a stream */ 151 struct pcm *pcm_open(unsigned int card, unsigned int device, 152 unsigned int flags, struct pcm_config *config); 153 int pcm_close(struct pcm *pcm); 154 int pcm_is_ready(struct pcm *pcm); 155 156 /* Obtain the parameters for a PCM */ 157 struct pcm_params *pcm_params_get(unsigned int card, unsigned int device, 158 unsigned int flags); 159 void pcm_params_free(struct pcm_params *pcm_params); 160 161 struct pcm_mask *pcm_params_get_mask(struct pcm_params *pcm_params, 162 enum pcm_param param); 163 unsigned int pcm_params_get_min(struct pcm_params *pcm_params, 164 enum pcm_param param); 165 void pcm_params_set_min(struct pcm_params *pcm_params, 166 enum pcm_param param, unsigned int val); 167 unsigned int pcm_params_get_max(struct pcm_params *pcm_params, 168 enum pcm_param param); 169 void pcm_params_set_max(struct pcm_params *pcm_params, 170 enum pcm_param param, unsigned int val); 171 172 /* Converts the pcm parameters to a human readable string. 173 * The string parameter is a caller allocated buffer of size bytes, 174 * which is then filled up to size - 1 and null terminated, 175 * if size is greater than zero. 176 * The return value is the number of bytes copied to string 177 * (not including null termination) if less than size; otherwise, 178 * the number of bytes required for the buffer. 179 */ 180 int pcm_params_to_string(struct pcm_params *params, char *string, unsigned int size); 181 182 /* Returns 1 if the pcm_format is present (format bit set) in 183 * the pcm_params structure; 0 otherwise, or upon unrecognized format. 184 */ 185 int pcm_params_format_test(struct pcm_params *params, enum pcm_format format); 186 187 /* Set and get config */ 188 int pcm_get_config(struct pcm *pcm, struct pcm_config *config); 189 int pcm_set_config(struct pcm *pcm, struct pcm_config *config); 190 191 /* Returns a human readable reason for the last error */ 192 const char *pcm_get_error(struct pcm *pcm); 193 194 /* Returns the sample size in bits for a PCM format. 195 * As with ALSA formats, this is the storage size for the format, whereas the 196 * format represents the number of significant bits. For example, 197 * PCM_FORMAT_S24_LE uses 32 bits of storage. 198 */ 199 unsigned int pcm_format_to_bits(enum pcm_format format); 200 201 /* Returns the buffer size (int frames) that should be used for pcm_write. */ 202 unsigned int pcm_get_buffer_size(struct pcm *pcm); 203 unsigned int pcm_frames_to_bytes(struct pcm *pcm, unsigned int frames); 204 unsigned int pcm_bytes_to_frames(struct pcm *pcm, unsigned int bytes); 205 206 /* Returns the pcm latency in ms */ 207 unsigned int pcm_get_latency(struct pcm *pcm); 208 209 /* Returns available frames in pcm buffer and corresponding time stamp. 210 * The clock is CLOCK_MONOTONIC if flag PCM_MONOTONIC was specified in pcm_open, 211 * otherwise the clock is CLOCK_REALTIME. 212 * For an input stream, frames available are frames ready for the 213 * application to read. 214 * For an output stream, frames available are the number of empty frames available 215 * for the application to write. 216 */ 217 int pcm_get_htimestamp(struct pcm *pcm, unsigned int *avail, 218 struct timespec *tstamp); 219 220 /* Write data to the fifo. 221 * Will start playback on the first write or on a write that 222 * occurs after a fifo underrun. 223 */ 224 int pcm_write(struct pcm *pcm, const void *data, unsigned int count); 225 int pcm_read(struct pcm *pcm, void *data, unsigned int count); 226 227 /* 228 * mmap() support. 229 */ 230 int pcm_mmap_write(struct pcm *pcm, const void *data, unsigned int count); 231 int pcm_mmap_read(struct pcm *pcm, void *data, unsigned int count); 232 int pcm_mmap_begin(struct pcm *pcm, void **areas, unsigned int *offset, 233 unsigned int *frames); 234 int pcm_mmap_commit(struct pcm *pcm, unsigned int offset, unsigned int frames); 235 236 /* Prepare the PCM substream to be triggerable */ 237 int pcm_prepare(struct pcm *pcm); 238 /* Start and stop a PCM channel that doesn't transfer data */ 239 int pcm_start(struct pcm *pcm); 240 int pcm_stop(struct pcm *pcm); 241 242 /* Interrupt driven API */ 243 int pcm_wait(struct pcm *pcm, int timeout); 244 245 /* Change avail_min after the stream has been opened with no need to stop the stream. 246 * Only accepted if opened with PCM_MMAP and PCM_NOIRQ flags 247 */ 248 int pcm_set_avail_min(struct pcm *pcm, int avail_min); 249 250 /* 251 * MIXER API 252 */ 253 254 struct mixer; 255 struct mixer_ctl; 256 257 /* Open and close a mixer */ 258 struct mixer *mixer_open(unsigned int card); 259 void mixer_close(struct mixer *mixer); 260 261 /* Get info about a mixer */ 262 const char *mixer_get_name(struct mixer *mixer); 263 264 /* Obtain mixer controls */ 265 unsigned int mixer_get_num_ctls(struct mixer *mixer); 266 struct mixer_ctl *mixer_get_ctl(struct mixer *mixer, unsigned int id); 267 struct mixer_ctl *mixer_get_ctl_by_name(struct mixer *mixer, const char *name); 268 269 /* Get info about mixer controls */ 270 const char *mixer_ctl_get_name(struct mixer_ctl *ctl); 271 enum mixer_ctl_type mixer_ctl_get_type(struct mixer_ctl *ctl); 272 const char *mixer_ctl_get_type_string(struct mixer_ctl *ctl); 273 unsigned int mixer_ctl_get_num_values(struct mixer_ctl *ctl); 274 unsigned int mixer_ctl_get_num_enums(struct mixer_ctl *ctl); 275 const char *mixer_ctl_get_enum_string(struct mixer_ctl *ctl, 276 unsigned int enum_id); 277 278 /* Some sound cards update their controls due to external events, 279 * such as HDMI EDID byte data changing when an HDMI cable is 280 * connected. This API allows the count of elements to be updated. 281 */ 282 void mixer_ctl_update(struct mixer_ctl *ctl); 283 284 /* Set and get mixer controls */ 285 int mixer_ctl_get_percent(struct mixer_ctl *ctl, unsigned int id); 286 int mixer_ctl_set_percent(struct mixer_ctl *ctl, unsigned int id, int percent); 287 288 int mixer_ctl_get_value(struct mixer_ctl *ctl, unsigned int id); 289 int mixer_ctl_get_array(struct mixer_ctl *ctl, void *array, size_t count); 290 int mixer_ctl_set_value(struct mixer_ctl *ctl, unsigned int id, int value); 291 int mixer_ctl_set_array(struct mixer_ctl *ctl, const void *array, size_t count); 292 int mixer_ctl_set_enum_by_string(struct mixer_ctl *ctl, const char *string); 293 294 /* Determe range of integer mixer controls */ 295 int mixer_ctl_get_range_min(struct mixer_ctl *ctl); 296 int mixer_ctl_get_range_max(struct mixer_ctl *ctl); 297 298 #if defined(__cplusplus) 299 } /* extern "C" */ 300 #endif 301 302 #endif 303
