include/uapi/sound/compress_params.h

   1 /* SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) AND MIT) */
   2 /*
   3  *  compress_params.h - codec types and parameters for compressed data
   4  *  streaming interface
   5  *
   6  *  Copyright (C) 2011 Intel Corporation
   7  *  Authors:    Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
   8  *              Vinod Koul <vinod.koul@linux.intel.com>
   9  *
  10  *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  11  *
  12  *  This program is free software; you can redistribute it and/or modify
  13  *  it under the terms of the GNU General Public License as published by
  14  *  the Free Software Foundation; version 2 of the License.
  15  *
  16  *  This program is distributed in the hope that it will be useful, but
  17  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  18  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  19  *  General Public License for more details.
  20  *
  21  *  You should have received a copy of the GNU General Public License along
  22  *  with this program; if not, write to the Free Software Foundation, Inc.,
  23  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  24  *
  25  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  26  *
  27  * The definitions in this file are derived from the OpenMAX AL version 1.1
  28  * and OpenMAX IL v 1.1.2 header files which contain the copyright notice below.
  29  *
  30  * Copyright (c) 2007-2010 The Khronos Group Inc.
  31  *
  32  * Permission is hereby granted, free of charge, to any person obtaining
  33  * a copy of this software and/or associated documentation files (the
  34  * "Materials "), to deal in the Materials without restriction, including
  35  * without limitation the rights to use, copy, modify, merge, publish,
  36  * distribute, sublicense, and/or sell copies of the Materials, and to
  37  * permit persons to whom the Materials are furnished to do so, subject to
  38  * the following conditions:
  39  *
  40  * The above copyright notice and this permission notice shall be included
  41  * in all copies or substantial portions of the Materials.
  42  *
  43  * THE MATERIALS ARE PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  44  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  45  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
  46  * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
  47  * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  48  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  49  * MATERIALS OR THE USE OR OTHER DEALINGS IN THE MATERIALS.
  50  *
  51  */
  52 #ifndef __SND_COMPRESS_PARAMS_H
  53 #define __SND_COMPRESS_PARAMS_H
  54
  55 #include <linux/types.h>
  56
  57 /* AUDIO CODECS SUPPORTED */
  58 #define MAX_NUM_CODECS 32
  59 #define MAX_NUM_CODEC_DESCRIPTORS 32
  60 #define MAX_NUM_BITRATES 32
  61 #define MAX_NUM_SAMPLE_RATES 32
  62
  63 /* Codecs are listed linearly to allow for extensibility */
  64 #define SND_AUDIOCODEC_PCM                   ((__u32) 0x00000001)
  65 #define SND_AUDIOCODEC_MP3                   ((__u32) 0x00000002)
  66 #define SND_AUDIOCODEC_AMR                   ((__u32) 0x00000003)
  67 #define SND_AUDIOCODEC_AMRWB                 ((__u32) 0x00000004)
  68 #define SND_AUDIOCODEC_AMRWBPLUS             ((__u32) 0x00000005)
  69 #define SND_AUDIOCODEC_AAC                   ((__u32) 0x00000006)
  70 #define SND_AUDIOCODEC_WMA                   ((__u32) 0x00000007)
  71 #define SND_AUDIOCODEC_REAL                  ((__u32) 0x00000008)
  72 #define SND_AUDIOCODEC_VORBIS                ((__u32) 0x00000009)
  73 #define SND_AUDIOCODEC_FLAC                  ((__u32) 0x0000000A)
  74 #define SND_AUDIOCODEC_IEC61937              ((__u32) 0x0000000B)
  75 #define SND_AUDIOCODEC_G723_1                ((__u32) 0x0000000C)
  76 #define SND_AUDIOCODEC_G729                  ((__u32) 0x0000000D)
  77 #define SND_AUDIOCODEC_BESPOKE               ((__u32) 0x0000000E)
  78 #define SND_AUDIOCODEC_ALAC                  ((__u32) 0x0000000F)
  79 #define SND_AUDIOCODEC_APE                   ((__u32) 0x00000010)
  80 #define SND_AUDIOCODEC_MAX                   SND_AUDIOCODEC_APE
  81
  82 /*
  83  * Profile and modes are listed with bit masks. This allows for a
  84  * more compact representation of fields that will not evolve
  85  * (in contrast to the list of codecs)
  86  */
  87
  88 #define SND_AUDIOPROFILE_PCM                 ((__u32) 0x00000001)
  89
  90 /* MP3 modes are only useful for encoders */
  91 #define SND_AUDIOCHANMODE_MP3_MONO           ((__u32) 0x00000001)
  92 #define SND_AUDIOCHANMODE_MP3_STEREO         ((__u32) 0x00000002)
  93 #define SND_AUDIOCHANMODE_MP3_JOINTSTEREO    ((__u32) 0x00000004)
  94 #define SND_AUDIOCHANMODE_MP3_DUAL           ((__u32) 0x00000008)
  95
  96 #define SND_AUDIOPROFILE_AMR                 ((__u32) 0x00000001)
  97
  98 /* AMR modes are only useful for encoders */
  99 #define SND_AUDIOMODE_AMR_DTX_OFF            ((__u32) 0x00000001)
 100 #define SND_AUDIOMODE_AMR_VAD1               ((__u32) 0x00000002)
 101 #define SND_AUDIOMODE_AMR_VAD2               ((__u32) 0x00000004)
 102
 103 #define SND_AUDIOSTREAMFORMAT_UNDEFINED      ((__u32) 0x00000000)
 104 #define SND_AUDIOSTREAMFORMAT_CONFORMANCE    ((__u32) 0x00000001)
 105 #define SND_AUDIOSTREAMFORMAT_IF1            ((__u32) 0x00000002)
 106 #define SND_AUDIOSTREAMFORMAT_IF2            ((__u32) 0x00000004)
 107 #define SND_AUDIOSTREAMFORMAT_FSF            ((__u32) 0x00000008)
 108 #define SND_AUDIOSTREAMFORMAT_RTPPAYLOAD     ((__u32) 0x00000010)
 109 #define SND_AUDIOSTREAMFORMAT_ITU            ((__u32) 0x00000020)
 110
 111 #define SND_AUDIOPROFILE_AMRWB               ((__u32) 0x00000001)
 112
 113 /* AMRWB modes are only useful for encoders */
 114 #define SND_AUDIOMODE_AMRWB_DTX_OFF          ((__u32) 0x00000001)
 115 #define SND_AUDIOMODE_AMRWB_VAD1             ((__u32) 0x00000002)
 116 #define SND_AUDIOMODE_AMRWB_VAD2             ((__u32) 0x00000004)
 117
 118 #define SND_AUDIOPROFILE_AMRWBPLUS           ((__u32) 0x00000001)
 119
 120 #define SND_AUDIOPROFILE_AAC                 ((__u32) 0x00000001)
 121
 122 /* AAC modes are required for encoders and decoders */
 123 #define SND_AUDIOMODE_AAC_MAIN               ((__u32) 0x00000001)
 124 #define SND_AUDIOMODE_AAC_LC                 ((__u32) 0x00000002)
 125 #define SND_AUDIOMODE_AAC_SSR                ((__u32) 0x00000004)
 126 #define SND_AUDIOMODE_AAC_LTP                ((__u32) 0x00000008)
 127 #define SND_AUDIOMODE_AAC_HE                 ((__u32) 0x00000010)
 128 #define SND_AUDIOMODE_AAC_SCALABLE           ((__u32) 0x00000020)
 129 #define SND_AUDIOMODE_AAC_ERLC               ((__u32) 0x00000040)
 130 #define SND_AUDIOMODE_AAC_LD                 ((__u32) 0x00000080)
 131 #define SND_AUDIOMODE_AAC_HE_PS              ((__u32) 0x00000100)
 132 #define SND_AUDIOMODE_AAC_HE_MPS             ((__u32) 0x00000200)
 133
 134 /* AAC formats are required for encoders and decoders */
 135 #define SND_AUDIOSTREAMFORMAT_MP2ADTS        ((__u32) 0x00000001)
 136 #define SND_AUDIOSTREAMFORMAT_MP4ADTS        ((__u32) 0x00000002)
 137 #define SND_AUDIOSTREAMFORMAT_MP4LOAS        ((__u32) 0x00000004)
 138 #define SND_AUDIOSTREAMFORMAT_MP4LATM        ((__u32) 0x00000008)
 139 #define SND_AUDIOSTREAMFORMAT_ADIF           ((__u32) 0x00000010)
 140 #define SND_AUDIOSTREAMFORMAT_MP4FF          ((__u32) 0x00000020)
 141 #define SND_AUDIOSTREAMFORMAT_RAW            ((__u32) 0x00000040)
 142
 143 #define SND_AUDIOPROFILE_WMA7                ((__u32) 0x00000001)
 144 #define SND_AUDIOPROFILE_WMA8                ((__u32) 0x00000002)
 145 #define SND_AUDIOPROFILE_WMA9                ((__u32) 0x00000004)
 146 #define SND_AUDIOPROFILE_WMA10               ((__u32) 0x00000008)
 147 #define SND_AUDIOPROFILE_WMA9_PRO            ((__u32) 0x00000010)
 148 #define SND_AUDIOPROFILE_WMA9_LOSSLESS       ((__u32) 0x00000020)
 149 #define SND_AUDIOPROFILE_WMA10_LOSSLESS      ((__u32) 0x00000040)
 150
 151 #define SND_AUDIOMODE_WMA_LEVEL1             ((__u32) 0x00000001)
 152 #define SND_AUDIOMODE_WMA_LEVEL2             ((__u32) 0x00000002)
 153 #define SND_AUDIOMODE_WMA_LEVEL3             ((__u32) 0x00000004)
 154 #define SND_AUDIOMODE_WMA_LEVEL4             ((__u32) 0x00000008)
 155 #define SND_AUDIOMODE_WMAPRO_LEVELM0         ((__u32) 0x00000010)
 156 #define SND_AUDIOMODE_WMAPRO_LEVELM1         ((__u32) 0x00000020)
 157 #define SND_AUDIOMODE_WMAPRO_LEVELM2         ((__u32) 0x00000040)
 158 #define SND_AUDIOMODE_WMAPRO_LEVELM3         ((__u32) 0x00000080)
 159
 160 #define SND_AUDIOSTREAMFORMAT_WMA_ASF        ((__u32) 0x00000001)
 161 /*
 162  * Some implementations strip the ASF header and only send ASF packets
 163  * to the DSP
 164  */
 165 #define SND_AUDIOSTREAMFORMAT_WMA_NOASF_HDR  ((__u32) 0x00000002)
 166
 167 #define SND_AUDIOPROFILE_REALAUDIO           ((__u32) 0x00000001)
 168
 169 #define SND_AUDIOMODE_REALAUDIO_G2           ((__u32) 0x00000001)
 170 #define SND_AUDIOMODE_REALAUDIO_8            ((__u32) 0x00000002)
 171 #define SND_AUDIOMODE_REALAUDIO_10           ((__u32) 0x00000004)
 172 #define SND_AUDIOMODE_REALAUDIO_SURROUND     ((__u32) 0x00000008)
 173
 174 #define SND_AUDIOPROFILE_VORBIS              ((__u32) 0x00000001)
 175
 176 #define SND_AUDIOMODE_VORBIS                 ((__u32) 0x00000001)
 177
 178 #define SND_AUDIOPROFILE_FLAC                ((__u32) 0x00000001)
 179
 180 /*
 181  * Define quality levels for FLAC encoders, from LEVEL0 (fast)
 182  * to LEVEL8 (best)
 183  */
 184 #define SND_AUDIOMODE_FLAC_LEVEL0            ((__u32) 0x00000001)
 185 #define SND_AUDIOMODE_FLAC_LEVEL1            ((__u32) 0x00000002)
 186 #define SND_AUDIOMODE_FLAC_LEVEL2            ((__u32) 0x00000004)
 187 #define SND_AUDIOMODE_FLAC_LEVEL3            ((__u32) 0x00000008)
 188 #define SND_AUDIOMODE_FLAC_LEVEL4            ((__u32) 0x00000010)
 189 #define SND_AUDIOMODE_FLAC_LEVEL5            ((__u32) 0x00000020)
 190 #define SND_AUDIOMODE_FLAC_LEVEL6            ((__u32) 0x00000040)
 191 #define SND_AUDIOMODE_FLAC_LEVEL7            ((__u32) 0x00000080)
 192 #define SND_AUDIOMODE_FLAC_LEVEL8            ((__u32) 0x00000100)
 193
 194 #define SND_AUDIOSTREAMFORMAT_FLAC           ((__u32) 0x00000001)
 195 #define SND_AUDIOSTREAMFORMAT_FLAC_OGG       ((__u32) 0x00000002)
 196
 197 /* IEC61937 payloads without CUVP and preambles */
 198 #define SND_AUDIOPROFILE_IEC61937            ((__u32) 0x00000001)
 199 /* IEC61937 with S/PDIF preambles+CUVP bits in 32-bit containers */
 200 #define SND_AUDIOPROFILE_IEC61937_SPDIF      ((__u32) 0x00000002)
 201
 202 /*
 203  * IEC modes are mandatory for decoders. Format autodetection
 204  * will only happen on the DSP side with mode 0. The PCM mode should
 205  * not be used, the PCM codec should be used instead.
 206  */
 207 #define SND_AUDIOMODE_IEC_REF_STREAM_HEADER  ((__u32) 0x00000000)
 208 #define SND_AUDIOMODE_IEC_LPCM               ((__u32) 0x00000001)
 209 #define SND_AUDIOMODE_IEC_AC3                ((__u32) 0x00000002)
 210 #define SND_AUDIOMODE_IEC_MPEG1              ((__u32) 0x00000004)
 211 #define SND_AUDIOMODE_IEC_MP3                ((__u32) 0x00000008)
 212 #define SND_AUDIOMODE_IEC_MPEG2              ((__u32) 0x00000010)
 213 #define SND_AUDIOMODE_IEC_AACLC              ((__u32) 0x00000020)
 214 #define SND_AUDIOMODE_IEC_DTS                ((__u32) 0x00000040)
 215 #define SND_AUDIOMODE_IEC_ATRAC              ((__u32) 0x00000080)
 216 #define SND_AUDIOMODE_IEC_SACD               ((__u32) 0x00000100)
 217 #define SND_AUDIOMODE_IEC_EAC3               ((__u32) 0x00000200)
 218 #define SND_AUDIOMODE_IEC_DTS_HD             ((__u32) 0x00000400)
 219 #define SND_AUDIOMODE_IEC_MLP                ((__u32) 0x00000800)
 220 #define SND_AUDIOMODE_IEC_DST                ((__u32) 0x00001000)
 221 #define SND_AUDIOMODE_IEC_WMAPRO             ((__u32) 0x00002000)
 222 #define SND_AUDIOMODE_IEC_REF_CXT            ((__u32) 0x00004000)
 223 #define SND_AUDIOMODE_IEC_HE_AAC             ((__u32) 0x00008000)
 224 #define SND_AUDIOMODE_IEC_HE_AAC2            ((__u32) 0x00010000)
 225 #define SND_AUDIOMODE_IEC_MPEG_SURROUND      ((__u32) 0x00020000)
 226
 227 #define SND_AUDIOPROFILE_G723_1              ((__u32) 0x00000001)
 228
 229 #define SND_AUDIOMODE_G723_1_ANNEX_A         ((__u32) 0x00000001)
 230 #define SND_AUDIOMODE_G723_1_ANNEX_B         ((__u32) 0x00000002)
 231 #define SND_AUDIOMODE_G723_1_ANNEX_C         ((__u32) 0x00000004)
 232
 233 #define SND_AUDIOPROFILE_G729                ((__u32) 0x00000001)
 234
 235 #define SND_AUDIOMODE_G729_ANNEX_A           ((__u32) 0x00000001)
 236 #define SND_AUDIOMODE_G729_ANNEX_B           ((__u32) 0x00000002)
 237
 238 /* <FIXME: multichannel encoders aren't supported for now. Would need
 239    an additional definition of channel arrangement> */
 240
 241 /* VBR/CBR definitions */
 242 #define SND_RATECONTROLMODE_CONSTANTBITRATE  ((__u32) 0x00000001)
 243 #define SND_RATECONTROLMODE_VARIABLEBITRATE  ((__u32) 0x00000002)
 244
 245 /* Encoder options */
 246
 247 struct snd_enc_wma {
 248         __u32 super_block_align; /* WMA Type-specific data */
 249 };
 250
 251
 252 /**
 253  * struct snd_enc_vorbis
 254  * @quality: Sets encoding quality to n, between -1 (low) and 10 (high).
 255  * In the default mode of operation, the quality level is 3.
 256  * Normal quality range is 0 - 10.
 257  * @managed: Boolean. Set  bitrate  management  mode. This turns off the
 258  * normal VBR encoding, but allows hard or soft bitrate constraints to be
 259  * enforced by the encoder. This mode can be slower, and may also be
 260  * lower quality. It is primarily useful for streaming.
 261  * @max_bit_rate: Enabled only if managed is TRUE
 262  * @min_bit_rate: Enabled only if managed is TRUE
 263  * @downmix: Boolean. Downmix input from stereo to mono (has no effect on
 264  * non-stereo streams). Useful for lower-bitrate encoding.
 265  *
 266  * These options were extracted from the OpenMAX IL spec and Gstreamer vorbisenc
 267  * properties
 268  *
 269  * For best quality users should specify VBR mode and set quality levels.
 270  */
 271
 272 struct snd_enc_vorbis {
 273         __s32 quality;
 274         __u32 managed;
 275         __u32 max_bit_rate;
 276         __u32 min_bit_rate;
 277         __u32 downmix;
 278 } __attribute__((packed, aligned(4)));
 279
 280
 281 /**
 282  * struct snd_enc_real
 283  * @quant_bits: number of coupling quantization bits in the stream
 284  * @start_region: coupling start region in the stream
 285  * @num_regions: number of regions value
 286  *
 287  * These options were extracted from the OpenMAX IL spec
 288  */
 289
 290 struct snd_enc_real {
 291         __u32 quant_bits;
 292         __u32 start_region;
 293         __u32 num_regions;
 294 } __attribute__((packed, aligned(4)));
 295
 296 /**
 297  * struct snd_enc_flac
 298  * @num: serial number, valid only for OGG formats
 299  *      needs to be set by application
 300  * @gain: Add replay gain tags
 301  *
 302  * These options were extracted from the FLAC online documentation
 303  * at http://flac.sourceforge.net/documentation_tools_flac.html
 304  *
 305  * To make the API simpler, it is assumed that the user will select quality
 306  * profiles. Additional options that affect encoding quality and speed can
 307  * be added at a later stage if needed.
 308  *
 309  * By default the Subset format is used by encoders.
 310  *
 311  * TAGS such as pictures, etc, cannot be handled by an offloaded encoder and are
 312  * not supported in this API.
 313  */
 314
 315 struct snd_enc_flac {
 316         __u32 num;
 317         __u32 gain;
 318 } __attribute__((packed, aligned(4)));
 319
 320 struct snd_enc_generic {
 321         __u32 bw;       /* encoder bandwidth */
 322         __s32 reserved[15];     /* Can be used for SND_AUDIOCODEC_BESPOKE */
 323 } __attribute__((packed, aligned(4)));
 324
 325 struct snd_dec_flac {
 326         __u16 sample_size;
 327         __u16 min_blk_size;
 328         __u16 max_blk_size;
 329         __u16 min_frame_size;
 330         __u16 max_frame_size;
 331         __u16 reserved;
 332 } __attribute__((packed, aligned(4)));
 333
 334 struct snd_dec_wma {
 335         __u32 encoder_option;
 336         __u32 adv_encoder_option;
 337         __u32 adv_encoder_option2;
 338         __u32 reserved;
 339 } __attribute__((packed, aligned(4)));
 340
 341 struct snd_dec_alac {
 342         __u32 frame_length;
 343         __u8 compatible_version;
 344         __u8 pb;
 345         __u8 mb;
 346         __u8 kb;
 347         __u32 max_run;
 348         __u32 max_frame_bytes;
 349 } __attribute__((packed, aligned(4)));
 350
 351 struct snd_dec_ape {
 352         __u16 compatible_version;
 353         __u16 compression_level;
 354         __u32 format_flags;
 355         __u32 blocks_per_frame;
 356         __u32 final_frame_blocks;
 357         __u32 total_frames;
 358         __u32 seek_table_present;
 359 } __attribute__((packed, aligned(4)));
 360
 361 union snd_codec_options {
 362         struct snd_enc_wma wma;
 363         struct snd_enc_vorbis vorbis;
 364         struct snd_enc_real real;
 365         struct snd_enc_flac flac;
 366         struct snd_enc_generic generic;
 367         struct snd_dec_flac flac_d;
 368         struct snd_dec_wma wma_d;
 369         struct snd_dec_alac alac_d;
 370         struct snd_dec_ape ape_d;
 371 } __attribute__((packed, aligned(4)));
 372
 373 /** struct snd_codec_desc - description of codec capabilities
 374  * @max_ch: Maximum number of audio channels
 375  * @sample_rates: Sampling rates in Hz, use values like 48000 for this
 376  * @num_sample_rates: Number of valid values in sample_rates array
 377  * @bit_rate: Indexed array containing supported bit rates
 378  * @num_bitrates: Number of valid values in bit_rate array
 379  * @rate_control: value is specified by SND_RATECONTROLMODE defines.
 380  * @profiles: Supported profiles. See SND_AUDIOPROFILE defines.
 381  * @modes: Supported modes. See SND_AUDIOMODE defines
 382  * @formats: Supported formats. See SND_AUDIOSTREAMFORMAT defines
 383  * @min_buffer: Minimum buffer size handled by codec implementation
 384  * @reserved: reserved for future use
 385  *
 386  * This structure provides a scalar value for profiles, modes and stream
 387  * format fields.
 388  * If an implementation supports multiple combinations, they will be listed as
 389  * codecs with different descriptors, for example there would be 2 descriptors
 390  * for AAC-RAW and AAC-ADTS.
 391  * This entails some redundancy but makes it easier to avoid invalid
 392  * configurations.
 393  *
 394  */
 395
 396 struct snd_codec_desc {
 397         __u32 max_ch;
 398         __u32 sample_rates[MAX_NUM_SAMPLE_RATES];
 399         __u32 num_sample_rates;
 400         __u32 bit_rate[MAX_NUM_BITRATES];
 401         __u32 num_bitrates;
 402         __u32 rate_control;
 403         __u32 profiles;
 404         __u32 modes;
 405         __u32 formats;
 406         __u32 min_buffer;
 407         __u32 reserved[15];
 408 } __attribute__((packed, aligned(4)));
 409
 410 /** struct snd_codec
 411  * @id: Identifies the supported audio encoder/decoder.
 412  *              See SND_AUDIOCODEC macros.
 413  * @ch_in: Number of input audio channels
 414  * @ch_out: Number of output channels. In case of contradiction between
 415  *              this field and the channelMode field, the channelMode field
 416  *              overrides.
 417  * @sample_rate: Audio sample rate of input data in Hz, use values like 48000
 418  *              for this.
 419  * @bit_rate: Bitrate of encoded data. May be ignored by decoders
 420  * @rate_control: Encoding rate control. See SND_RATECONTROLMODE defines.
 421  *               Encoders may rely on profiles for quality levels.
 422  *               May be ignored by decoders.
 423  * @profile: Mandatory for encoders, can be mandatory for specific
 424  *              decoders as well. See SND_AUDIOPROFILE defines.
 425  * @level: Supported level (Only used by WMA at the moment)
 426  * @ch_mode: Channel mode for encoder. See SND_AUDIOCHANMODE defines
 427  * @format: Format of encoded bistream. Mandatory when defined.
 428  *              See SND_AUDIOSTREAMFORMAT defines.
 429  * @align: Block alignment in bytes of an audio sample.
 430  *              Only required for PCM or IEC formats.
 431  * @options: encoder-specific settings
 432  * @reserved: reserved for future use
 433  */
 434
 435 struct snd_codec {
 436         __u32 id;
 437         __u32 ch_in;
 438         __u32 ch_out;
 439         __u32 sample_rate;
 440         __u32 bit_rate;
 441         __u32 rate_control;
 442         __u32 profile;
 443         __u32 level;
 444         __u32 ch_mode;
 445         __u32 format;
 446         __u32 align;
 447         union snd_codec_options options;
 448         __u32 reserved[3];
 449 } __attribute__((packed, aligned(4)));
 450
 451 #endif