Harald Welte | 065dab8 | 2022-11-29 23:13:06 +0100 | [diff] [blame] | 1 | /* V.110 frames according to ITU-T V.110 |
| 2 | * |
| 3 | * This code implements the following functionality: |
| 4 | * - parsing/encoding of osmo_v110_decoded_frame from/to actual 80-bit V.110 frame |
| 5 | * - synchronous rate adapting of user bit rate to V.110 D-bits as per Table 6 |
| 6 | * |
| 7 | * It is (at least initially) a very "naive" implementation, as it first and foremost |
| 8 | * aims to be functional and correct, rather than efficient in any way. Hence it |
| 9 | * operates on unpacked bits (ubit_t, 1 bit per byte), and has various intermediate |
| 10 | * representations and indirect function calls. If needed, a more optimized variant |
| 11 | * can always be developed later on. |
| 12 | */ |
| 13 | |
| 14 | /* (C) 2022 by Harald Welte <laforge@osmocom.org> |
| 15 | * |
| 16 | * SPDX-License-Identifier: GPL-2.0+ |
| 17 | * |
| 18 | * This program is free software; you can redistribute it and/or modify |
| 19 | * it under the terms of the GNU General Public License as published by |
| 20 | * the Free Software Foundation; either version 2 of the License, or |
| 21 | * (at your option) any later version. |
| 22 | * |
| 23 | * This program is distributed in the hope that it will be useful, |
| 24 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 25 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 26 | * GNU General Public License for more details. |
| 27 | */ |
| 28 | |
| 29 | #include <stdint.h> |
| 30 | #include <errno.h> |
| 31 | |
| 32 | #include <osmocom/core/bits.h> |
| 33 | |
| 34 | #include <osmocom/isdn/v110.h> |
| 35 | |
| 36 | /************************************************************************* |
| 37 | * V.110 frame decoding/encoding (ubits <-> struct with D/S/X/E bits) |
| 38 | *************************************************************************/ |
| 39 | |
| 40 | /*! Decode a 80-bit V.110 frame present as 80 ubits into a struct osmo_v110_decoded_frame. |
| 41 | * \param[out] fr caller-allocated output data structure, filled by this function |
| 42 | * \param[in] ra_bits One V.110 frame as 80 unpacked bits. |
| 43 | * \param[in] n_bits number of unpacked bits provided in ra_bits |
| 44 | * \returns 0 in case of success; negative on error. */ |
| 45 | int osmo_v110_decode_frame(struct osmo_v110_decoded_frame *fr, const ubit_t *ra_bits, size_t n_bits) |
| 46 | { |
| 47 | if (n_bits < 80) |
| 48 | return -EINVAL; |
| 49 | |
| 50 | /* X1 .. X2 */ |
| 51 | fr->x_bits[0] = ra_bits[2 * 8 + 7]; |
| 52 | fr->x_bits[1] = ra_bits[7 * 8 + 7]; |
| 53 | |
| 54 | /* S1, S3, S4, S6, S8, S9 */ |
| 55 | fr->s_bits[0] = ra_bits[1 * 8 + 7]; |
| 56 | fr->s_bits[2] = ra_bits[3 * 8 + 7]; |
| 57 | fr->s_bits[3] = ra_bits[4 * 8 + 7]; |
| 58 | fr->s_bits[5] = ra_bits[6 * 8 + 7]; |
| 59 | fr->s_bits[7] = ra_bits[8 * 8 + 7]; |
| 60 | fr->s_bits[8] = ra_bits[9 * 8 + 7]; |
| 61 | |
| 62 | /* E1 .. E7 */ |
| 63 | memcpy(fr->e_bits, ra_bits + 5 * 8 + 1, 7); |
| 64 | |
| 65 | /* D-bits */ |
| 66 | memcpy(fr->d_bits + 0 * 6, ra_bits + 1 * 8 + 1, 6); |
| 67 | memcpy(fr->d_bits + 1 * 6, ra_bits + 2 * 8 + 1, 6); |
| 68 | memcpy(fr->d_bits + 2 * 6, ra_bits + 3 * 8 + 1, 6); |
| 69 | memcpy(fr->d_bits + 3 * 6, ra_bits + 4 * 8 + 1, 6); |
| 70 | |
| 71 | memcpy(fr->d_bits + 4 * 6, ra_bits + 6 * 8 + 1, 6); |
| 72 | memcpy(fr->d_bits + 5 * 6, ra_bits + 7 * 8 + 1, 6); |
| 73 | memcpy(fr->d_bits + 6 * 6, ra_bits + 8 * 8 + 1, 6); |
| 74 | memcpy(fr->d_bits + 7 * 6, ra_bits + 9 * 8 + 1, 6); |
| 75 | |
| 76 | return 0; |
| 77 | } |
| 78 | |
| 79 | /*! Encode a struct osmo_v110_decoded_frame into an 80-bit V.110 frame as ubits. |
| 80 | * \param[out] ra_bits caller-provided output buffer at leat 80 ubits large |
| 81 | * \param[in] n_bits length of ra_bits. Must be at least 80. |
| 82 | * \param[in] input data structure |
| 83 | * \returns number of bits written to ra_bits */ |
| 84 | int osmo_v110_encode_frame(ubit_t *ra_bits, size_t n_bits, const struct osmo_v110_decoded_frame *fr) |
| 85 | { |
| 86 | if (n_bits < 80) |
| 87 | return -ENOSPC; |
| 88 | |
| 89 | /* alignment pattern */ |
| 90 | memset(ra_bits+0, 0, 8); |
| 91 | for (int i = 1; i < 10; i++) |
| 92 | ra_bits[i*8] = 1; |
| 93 | |
| 94 | /* X1 .. X2 */ |
| 95 | ra_bits[2 * 8 + 7] = fr->x_bits[0]; |
| 96 | ra_bits[7 * 8 + 7] = fr->x_bits[1]; |
| 97 | |
| 98 | /* S1, S3, S4, S6, S8, S9 */ |
| 99 | ra_bits[1 * 8 + 7] = fr->s_bits[0]; |
| 100 | ra_bits[3 * 8 + 7] = fr->s_bits[2]; |
| 101 | ra_bits[4 * 8 + 7] = fr->s_bits[3]; |
| 102 | ra_bits[6 * 8 + 7] = fr->s_bits[5]; |
| 103 | ra_bits[8 * 8 + 7] = fr->s_bits[7]; |
| 104 | ra_bits[9 * 8 + 7] = fr->s_bits[8]; |
| 105 | |
| 106 | /* E1 .. E7 */ |
| 107 | memcpy(ra_bits + 5 * 8 + 1, fr->e_bits, 7); |
| 108 | |
| 109 | /* D-bits */ |
| 110 | memcpy(ra_bits + 1 * 8 + 1, fr->d_bits + 0 * 6, 6); |
| 111 | memcpy(ra_bits + 2 * 8 + 1, fr->d_bits + 1 * 6, 6); |
| 112 | memcpy(ra_bits + 3 * 8 + 1, fr->d_bits + 2 * 6, 6); |
| 113 | memcpy(ra_bits + 4 * 8 + 1, fr->d_bits + 3 * 6, 6); |
| 114 | |
| 115 | memcpy(ra_bits + 6 * 8 + 1, fr->d_bits + 4 * 6, 6); |
| 116 | memcpy(ra_bits + 7 * 8 + 1, fr->d_bits + 5 * 6, 6); |
| 117 | memcpy(ra_bits + 8 * 8 + 1, fr->d_bits + 6 * 6, 6); |
| 118 | memcpy(ra_bits + 9 * 8 + 1, fr->d_bits + 7 * 6, 6); |
| 119 | |
| 120 | return 10 * 8; |
| 121 | } |
| 122 | |
| 123 | /*! Print a encoded V.110 frame in the same table-like structure as the spec. |
| 124 | * \param outf output FILE stream to which to dump |
| 125 | * \param[in] fr unpacked bits to dump |
| 126 | * \param[in] in_len length of unpacked bits available at fr. */ |
| 127 | void osmo_v110_ubit_dump(FILE *outf, const ubit_t *fr, size_t in_len) |
| 128 | { |
| 129 | if (in_len < 80) |
| 130 | fprintf(outf, "short input data\n"); |
| 131 | |
| 132 | for (unsigned int octet = 0; octet < 10; octet++) { |
| 133 | fprintf(outf, "%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\n", |
| 134 | fr[octet * 8 + 0], fr[octet * 8 + 1], fr[octet * 8 + 2], fr[octet * 8 + 3], |
| 135 | fr[octet * 8 + 4], fr[octet * 8 + 5], fr[octet * 8 + 6], fr[octet * 8 + 7]); |
| 136 | } |
| 137 | } |
| 138 | |
| 139 | /************************************************************************* |
| 140 | * RA1 synchronous rate adaptation |
| 141 | *************************************************************************/ |
| 142 | |
| 143 | /* I actually couldn't find any reference as to the value of F(ill) bits */ |
| 144 | #define F 1 |
| 145 | |
| 146 | /*! Adapt from 6 synchronous 600bit/s input bits to a decoded V.110 frame. |
| 147 | * \param[out] fr caller-allocated output frame to which E+D bits are stored |
| 148 | * \param[in] d_in input user bits |
| 149 | * \param[in] in_len number of bits in d_in. Must be 6. |
| 150 | * \returns 0 on success; negative in case of error. */ |
| 151 | static int v110_adapt_600_to_IR8000(struct osmo_v110_decoded_frame *fr, const ubit_t *d_in, size_t in_len) |
| 152 | { |
| 153 | if (in_len != 6) |
| 154 | return -EINVAL; |
| 155 | |
| 156 | /* Table 6a / V.110 */ |
| 157 | fr->e_bits[0] = 1; |
| 158 | fr->e_bits[1] = 0; |
| 159 | fr->e_bits[2] = 0; |
| 160 | for (int i = 0; i < 6; i++) |
| 161 | memset(fr->d_bits + i*8, d_in[i], 8); |
| 162 | |
| 163 | return 0; |
| 164 | } |
| 165 | |
| 166 | static int v110_adapt_IR8000_to_600(ubit_t *d_out, size_t out_len, const struct osmo_v110_decoded_frame *fr) |
| 167 | { |
| 168 | if (out_len < 6) |
| 169 | return -ENOSPC; |
| 170 | |
| 171 | if (fr->e_bits[0] != 1 || fr->e_bits[1] != 0 || fr->e_bits[2] != 0) |
| 172 | return -EINVAL; |
| 173 | |
| 174 | for (int i = 0; i < 6; i++) { |
| 175 | /* we only use one of the bits, not some kind of consistency check or majority vote */ |
| 176 | d_out[i] = fr->d_bits[i*8]; |
| 177 | } |
| 178 | |
| 179 | return 6; |
| 180 | } |
| 181 | |
| 182 | /*! Adapt from 12 synchronous 1200bit/s input bits to a decoded V.110 frame. |
| 183 | * \param[out] fr caller-allocated output frame to which E+D bits are stored |
| 184 | * \param[in] d_in input user bits |
| 185 | * \param[in] in_len number of bits in d_in. Must be 12. |
| 186 | * \returns 0 on success; negative in case of error. */ |
| 187 | static int v110_adapt_1200_to_IR8000(struct osmo_v110_decoded_frame *fr, const ubit_t *d_in, size_t in_len) |
| 188 | { |
| 189 | if (in_len != 12) |
| 190 | return -EINVAL; |
| 191 | |
| 192 | /* Table 6b / V.110 */ |
| 193 | fr->e_bits[0] = 0; |
| 194 | fr->e_bits[1] = 1; |
| 195 | fr->e_bits[2] = 0; |
| 196 | for (int i = 0; i < 12; i++) |
| 197 | memset(fr->d_bits + i*4, d_in[i], 4); |
| 198 | |
| 199 | return 0; |
| 200 | } |
| 201 | |
| 202 | static int v110_adapt_IR8000_to_1200(ubit_t *d_out, size_t out_len, const struct osmo_v110_decoded_frame *fr) |
| 203 | { |
| 204 | if (out_len < 12) |
| 205 | return -ENOSPC; |
| 206 | |
| 207 | if (fr->e_bits[0] != 0 || fr->e_bits[1] != 1 || fr->e_bits[2] != 0) |
| 208 | return -EINVAL; |
| 209 | |
| 210 | for (int i = 0; i < 12; i++) { |
| 211 | /* we only use one of the bits, not some kind of consistency check or majority vote */ |
| 212 | d_out[i] = fr->d_bits[i*4]; |
| 213 | } |
| 214 | |
| 215 | return 12; |
| 216 | } |
| 217 | |
| 218 | /*! Adapt from 24 synchronous 2400bit/s input bits to a decoded V.110 frame. |
| 219 | * \param[out] fr caller-allocated output frame to which E+D bits are stored |
| 220 | * \param[in] d_in input user bits |
| 221 | * \param[in] in_len number of bits in d_in. Must be 24. |
| 222 | * \returns 0 on success; negative in case of error. */ |
| 223 | static int v110_adapt_2400_to_IR8000(struct osmo_v110_decoded_frame *fr, const ubit_t *d_in, size_t in_len) |
| 224 | { |
| 225 | if (in_len != 24) |
| 226 | return -EINVAL; |
| 227 | |
| 228 | /* Table 6c / V.110 */ |
| 229 | fr->e_bits[0] = 1; |
| 230 | fr->e_bits[1] = 1; |
| 231 | fr->e_bits[2] = 0; |
| 232 | for (int i = 0; i < 24; i++) { |
| 233 | fr->d_bits[i*2 + 0] = d_in[i]; |
| 234 | fr->d_bits[i*2 + 1] = d_in[i]; |
| 235 | } |
| 236 | |
| 237 | return 0; |
| 238 | } |
| 239 | |
| 240 | static int v110_adapt_IR8000_to_2400(ubit_t *d_out, size_t out_len, const struct osmo_v110_decoded_frame *fr) |
| 241 | { |
| 242 | if (out_len < 24) |
| 243 | return -ENOSPC; |
| 244 | |
Vadim Yanitskiy | 25127fb | 2023-03-17 17:08:18 +0700 | [diff] [blame] | 245 | /* Table 6c / V.110 */ |
| 246 | if (fr->e_bits[0] != 1 || fr->e_bits[1] != 1 || fr->e_bits[2] != 0) |
Harald Welte | 065dab8 | 2022-11-29 23:13:06 +0100 | [diff] [blame] | 247 | return -EINVAL; |
| 248 | |
| 249 | for (int i = 0; i < 24; i++) { |
| 250 | /* we only use one of the bits, not some kind of consistency check or majority vote */ |
| 251 | d_out[i] = fr->d_bits[i*2]; |
| 252 | } |
| 253 | |
| 254 | return 24; |
| 255 | } |
| 256 | |
| 257 | /*! Adapt from 36 synchronous N x 3600bit/s input bits to a decoded V.110 frame. |
| 258 | * \param[out] fr caller-allocated output frame to which E+D bits are stored |
| 259 | * \param[in] d_in input user bits |
| 260 | * \param[in] in_len number of bits in d_in. Must be 36. |
| 261 | * \returns 0 on success; negative in case of error. */ |
| 262 | static int v110_adapt_Nx3600_to_IR(struct osmo_v110_decoded_frame *fr, const ubit_t *d_in, size_t in_len) |
| 263 | { |
| 264 | int d_idx = 0; |
| 265 | |
| 266 | if (in_len != 36) |
| 267 | return -EINVAL; |
| 268 | |
| 269 | /* Table 6d / V.110 */ |
| 270 | fr->e_bits[0] = 1; |
| 271 | fr->e_bits[1] = 0; |
| 272 | fr->e_bits[2] = 1; |
| 273 | |
| 274 | memcpy(fr->d_bits + d_idx, d_in + 0, 10); d_idx += 10; /* D1..D10 */ |
| 275 | memset(fr->d_bits + d_idx, F, 2); d_idx += 2; |
| 276 | memcpy(fr->d_bits + d_idx, d_in + 10, 2); d_idx += 2; /* D11..D12 */ |
| 277 | memset(fr->d_bits + d_idx, F, 2); d_idx += 2; |
| 278 | memcpy(fr->d_bits + d_idx, d_in + 12, 2); d_idx += 2; /* D13..D14 */ |
| 279 | memset(fr->d_bits + d_idx, F, 2); d_idx += 2; |
| 280 | memcpy(fr->d_bits + d_idx, d_in + 14, 14); d_idx += 14; /* D15..D28 */ |
| 281 | memset(fr->d_bits + d_idx, F, 2); d_idx += 2; |
| 282 | memcpy(fr->d_bits + d_idx, d_in + 28, 2); d_idx += 2; /* D29..D30 */ |
| 283 | memset(fr->d_bits + d_idx, F, 2); d_idx += 2; |
| 284 | memcpy(fr->d_bits + d_idx, d_in + 30, 2); d_idx += 2; /* D31..D32 */ |
| 285 | memset(fr->d_bits + d_idx, F, 2); d_idx += 2; |
| 286 | memcpy(fr->d_bits + d_idx, d_in + 32, 4); d_idx += 4; /* D33..D36 */ |
| 287 | |
| 288 | OSMO_ASSERT(d_idx == 48); |
| 289 | |
| 290 | return 0; |
| 291 | } |
| 292 | |
| 293 | static int v110_adapt_IR_to_Nx3600(ubit_t *d_out, size_t out_len, const struct osmo_v110_decoded_frame *fr) |
| 294 | { |
| 295 | int d_idx = 0; |
| 296 | |
| 297 | if (out_len < 36) |
| 298 | return -ENOSPC; |
| 299 | |
| 300 | if (fr->e_bits[0] != 1 || fr->e_bits[1] != 0 || fr->e_bits[2] != 1) |
| 301 | return -EINVAL; |
| 302 | |
| 303 | memcpy(d_out + 0, fr->d_bits + d_idx, 10); d_idx += 10; /* D1..D10 */ |
| 304 | d_idx += 2; |
| 305 | memcpy(d_out + 10, fr->d_bits + d_idx, 2); d_idx += 2; /* D11..D12 */ |
| 306 | d_idx += 2; |
| 307 | memcpy(d_out + 12, fr->d_bits + d_idx, 2); d_idx += 2; /* D13..D14 */ |
| 308 | d_idx += 2; |
| 309 | memcpy(d_out + 14, fr->d_bits + d_idx, 14); d_idx += 14;/* D15..D28 */ |
| 310 | d_idx += 2; |
| 311 | memcpy(d_out + 28, fr->d_bits + d_idx, 2); d_idx += 2; /* D29..D30 */ |
| 312 | d_idx += 2; |
| 313 | memcpy(d_out + 30, fr->d_bits + d_idx, 2); d_idx += 2; /* D31..D32 */ |
| 314 | d_idx += 2; |
| 315 | memcpy(d_out + 32, fr->d_bits + d_idx, 4); d_idx += 4; /* D33..D36 */ |
| 316 | |
| 317 | OSMO_ASSERT(d_idx == 48); |
| 318 | |
| 319 | return 36; |
| 320 | } |
| 321 | |
| 322 | |
| 323 | /*! Adapt from 48 synchronous N x 4800bit/s input bits to a decoded V.110 frame. |
| 324 | * \param[out] fr caller-allocated output frame to which E+D bits are stored |
| 325 | * \param[in] d_in input user bits |
| 326 | * \param[in] in_len number of bits in d_in. Must be 48. |
| 327 | * \returns 0 on success; negative in case of error. */ |
| 328 | static int v110_adapt_Nx4800_to_IR(struct osmo_v110_decoded_frame *fr, const ubit_t *d_in, size_t in_len) |
| 329 | { |
| 330 | if (in_len != 48) |
| 331 | return -EINVAL; |
| 332 | |
| 333 | /* Table 6e / V.110 */ |
| 334 | fr->e_bits[0] = 0; |
| 335 | fr->e_bits[1] = 1; |
| 336 | fr->e_bits[2] = 1; |
| 337 | |
| 338 | memcpy(fr->d_bits, d_in, 48); |
| 339 | |
| 340 | return 0; |
| 341 | } |
| 342 | |
| 343 | static int v110_adapt_IR_to_Nx4800(ubit_t *d_out, size_t out_len, const struct osmo_v110_decoded_frame *fr) |
| 344 | { |
| 345 | if (out_len < 48) |
| 346 | return -ENOSPC; |
| 347 | |
| 348 | if (fr->e_bits[0] != 0 || fr->e_bits[1] != 1 || fr->e_bits[2] != 1) |
| 349 | return -EINVAL; |
| 350 | |
| 351 | memcpy(d_out, fr->d_bits, 48); |
| 352 | |
| 353 | return 48; |
| 354 | } |
| 355 | |
| 356 | /*! Adapt from 30 synchronous N x 12000bit/s input bits to a decoded V.110 frame. |
| 357 | * \param[out] fr caller-allocated output frame to which E+D bits are stored |
| 358 | * \param[in] d_in input user bits |
| 359 | * \param[in] in_len number of bits in d_in. Must be 30. |
| 360 | * \returns 0 on success; negative in case of error. */ |
| 361 | static int v110_adapt_Nx12000_to_IR(struct osmo_v110_decoded_frame *fr, const ubit_t *d_in, size_t in_len) |
| 362 | { |
| 363 | int d_idx = 0; |
| 364 | |
| 365 | if (in_len != 30) |
| 366 | return -EINVAL; |
| 367 | |
| 368 | /* Table 6f / V.110 */ |
| 369 | fr->e_bits[0] = 0; |
| 370 | fr->e_bits[1] = 0; |
| 371 | fr->e_bits[2] = 1; |
| 372 | |
| 373 | memcpy(fr->d_bits + d_idx, d_in + 0, 10); d_idx += 10; /* D1..D10 */ |
| 374 | memset(fr->d_bits + d_idx, F, 2); d_idx += 2; |
| 375 | memcpy(fr->d_bits + d_idx, d_in + 10, 2); d_idx += 2; /* D11..D12 */ |
| 376 | memset(fr->d_bits + d_idx, F, 2); d_idx += 2; |
| 377 | memcpy(fr->d_bits + d_idx, d_in + 12, 2); d_idx += 2; /* D13..D14 */ |
| 378 | memset(fr->d_bits + d_idx, F, 2); d_idx += 2; |
| 379 | fr->d_bits[d_idx++] = d_in[14]; /* D15 */ |
| 380 | memset(fr->d_bits + d_idx, F, 3); d_idx += 3; |
| 381 | memcpy(fr->d_bits + d_idx, d_in + 15, 10); d_idx += 10; /* D16..D25 */ |
| 382 | memset(fr->d_bits + d_idx, F, 2); d_idx += 2; |
| 383 | memcpy(fr->d_bits + d_idx, d_in + 25, 2); d_idx += 2; /* D26..D27 */ |
| 384 | memset(fr->d_bits + d_idx, F, 2); d_idx += 2; |
| 385 | memcpy(fr->d_bits + d_idx, d_in + 27, 2); d_idx += 2; /* D28..D29 */ |
| 386 | memset(fr->d_bits + d_idx, F, 2); d_idx += 2; |
| 387 | fr->d_bits[d_idx++] = d_in[29]; /* D30 */ |
| 388 | memset(fr->d_bits + d_idx, F, 3); d_idx += 3; |
| 389 | |
| 390 | OSMO_ASSERT(d_idx == 48); |
| 391 | |
| 392 | return 0; |
| 393 | } |
| 394 | |
| 395 | static int v110_adapt_IR_to_Nx12000(ubit_t *d_out, size_t out_len, const struct osmo_v110_decoded_frame *fr) |
| 396 | { |
| 397 | int d_idx = 0; |
| 398 | |
| 399 | if (out_len < 30) |
| 400 | return -ENOSPC; |
| 401 | |
| 402 | if (fr->e_bits[0] != 0 || fr->e_bits[1] != 0 || fr->e_bits[2] != 1) |
| 403 | return -EINVAL; |
| 404 | |
| 405 | memcpy(d_out + 0, fr->d_bits + d_idx, 10); d_idx += 10; /* D1..D10 */ |
| 406 | d_idx += 2; |
| 407 | memcpy(d_out + 10, fr->d_bits + d_idx, 2); d_idx += 2; /* D11..D12 */ |
| 408 | d_idx += 2; |
| 409 | memcpy(d_out + 12, fr->d_bits + d_idx, 2); d_idx += 2; /* D13..D14 */ |
| 410 | d_idx += 2; |
| 411 | d_out[14] = fr->d_bits[d_idx++]; /* D15 */ |
| 412 | d_idx += 3; |
| 413 | memcpy(d_out + 15, fr->d_bits + d_idx, 10); d_idx += 10;/* D16..D25 */ |
| 414 | d_idx += 2; |
| 415 | memcpy(d_out + 25, fr->d_bits + d_idx, 2); d_idx += 2; /* D26..D27 */ |
| 416 | d_idx += 2; |
| 417 | memcpy(d_out + 27, fr->d_bits + d_idx, 2); d_idx += 2; /* D28..D29 */ |
| 418 | d_idx += 2; |
| 419 | d_out[29] = fr->d_bits[d_idx++]; /* D30 */ |
| 420 | d_idx += 3; |
| 421 | |
| 422 | OSMO_ASSERT(d_idx == 48); |
| 423 | |
| 424 | return 30; |
| 425 | } |
| 426 | |
| 427 | /* definition of a synchronous V.110 RA1 rate adaptation. There is one for each supported tuple |
| 428 | * of user data rate and intermediate rate (IR). */ |
| 429 | struct osmo_v110_sync_ra1 { |
| 430 | unsigned int data_rate; |
| 431 | unsigned int intermediate_rate; |
| 432 | unsigned int user_data_chunk_bits; |
| 433 | /*! RA1 function in user bitrate -> intermediate rate direction */ |
| 434 | int (*adapt_user_to_ir)(struct osmo_v110_decoded_frame *fr, const ubit_t *d_in, size_t in_len); |
| 435 | /*! RA1 function in intermediate rate -> user bitrate direction */ |
| 436 | int (*adapt_ir_to_user)(ubit_t *d_out, size_t out_len, const struct osmo_v110_decoded_frame *fr); |
| 437 | }; |
| 438 | |
| 439 | /* all of the synchronous data signalling rates; see Table 1/V.110 */ |
| 440 | static const struct osmo_v110_sync_ra1 osmo_v110_sync_ra1_def[_NUM_OSMO_V110_SYNC_RA1] = { |
| 441 | [OSMO_V110_SYNC_RA1_600] = { |
| 442 | .data_rate = 600, |
| 443 | .intermediate_rate = 8000, |
| 444 | .user_data_chunk_bits = 6, |
| 445 | .adapt_user_to_ir = v110_adapt_600_to_IR8000, |
| 446 | .adapt_ir_to_user = v110_adapt_IR8000_to_600, |
| 447 | }, |
| 448 | [OSMO_V110_SYNC_RA1_1200] = { |
| 449 | .data_rate = 1200, |
| 450 | .intermediate_rate = 8000, |
| 451 | .user_data_chunk_bits = 12, |
| 452 | .adapt_user_to_ir = v110_adapt_1200_to_IR8000, |
| 453 | .adapt_ir_to_user = v110_adapt_IR8000_to_1200, |
| 454 | }, |
| 455 | [OSMO_V110_SYNC_RA1_2400] = { |
| 456 | .data_rate = 2400, |
| 457 | .intermediate_rate = 8000, |
| 458 | .user_data_chunk_bits = 24, |
| 459 | .adapt_user_to_ir = v110_adapt_2400_to_IR8000, |
| 460 | .adapt_ir_to_user = v110_adapt_IR8000_to_2400, |
| 461 | }, |
| 462 | [OSMO_V110_SYNC_RA1_4800] = { |
| 463 | .data_rate = 4800, |
| 464 | .intermediate_rate = 8000, |
| 465 | .user_data_chunk_bits = 48, |
| 466 | .adapt_user_to_ir = v110_adapt_Nx4800_to_IR, |
| 467 | .adapt_ir_to_user = v110_adapt_IR_to_Nx4800, |
| 468 | }, |
| 469 | [OSMO_V110_SYNC_RA1_7200] = { |
| 470 | .data_rate = 7200, |
| 471 | .intermediate_rate = 16000, |
| 472 | .user_data_chunk_bits = 36, |
| 473 | .adapt_user_to_ir = v110_adapt_Nx3600_to_IR, |
| 474 | .adapt_ir_to_user = v110_adapt_IR_to_Nx3600, |
| 475 | }, |
| 476 | [OSMO_V110_SYNC_RA1_9600] = { |
| 477 | .data_rate = 9600, |
| 478 | .intermediate_rate = 16000, |
| 479 | .user_data_chunk_bits = 48, |
| 480 | .adapt_user_to_ir = v110_adapt_Nx4800_to_IR, |
| 481 | .adapt_ir_to_user = v110_adapt_IR_to_Nx4800, |
| 482 | }, |
| 483 | [OSMO_V110_SYNC_RA1_12000] = { |
| 484 | .data_rate = 12000, |
| 485 | .intermediate_rate = 32000, |
| 486 | .user_data_chunk_bits = 30, |
| 487 | .adapt_user_to_ir = v110_adapt_Nx12000_to_IR, |
| 488 | .adapt_ir_to_user = v110_adapt_IR_to_Nx12000, |
| 489 | }, |
| 490 | [OSMO_V110_SYNC_RA1_14400] = { |
| 491 | .data_rate = 14400, |
| 492 | .intermediate_rate = 32000, |
| 493 | .user_data_chunk_bits = 36, |
| 494 | .adapt_user_to_ir = v110_adapt_Nx3600_to_IR, |
| 495 | .adapt_ir_to_user = v110_adapt_IR_to_Nx3600, |
| 496 | }, |
| 497 | [OSMO_V110_SYNC_RA1_19200] = { |
| 498 | .data_rate = 19200, |
| 499 | .intermediate_rate = 32000, |
| 500 | .user_data_chunk_bits = 48, |
| 501 | .adapt_user_to_ir = v110_adapt_Nx4800_to_IR, |
| 502 | .adapt_ir_to_user = v110_adapt_IR_to_Nx4800, |
| 503 | }, |
| 504 | [OSMO_V110_SYNC_RA1_24000] = { |
| 505 | .data_rate = 24000, |
| 506 | .intermediate_rate = 64000, |
| 507 | .user_data_chunk_bits = 30, |
| 508 | .adapt_user_to_ir = v110_adapt_Nx12000_to_IR, |
| 509 | .adapt_ir_to_user = v110_adapt_IR_to_Nx12000, |
| 510 | }, |
| 511 | [OSMO_V110_SYNC_RA1_28800] = { |
| 512 | .data_rate = 28800, |
| 513 | .intermediate_rate = 64000, |
| 514 | .user_data_chunk_bits = 36, |
| 515 | .adapt_user_to_ir = v110_adapt_Nx3600_to_IR, |
| 516 | .adapt_ir_to_user = v110_adapt_IR_to_Nx3600, |
| 517 | }, |
| 518 | [OSMO_V110_SYNC_RA1_38400] = { |
| 519 | .data_rate = 38400, |
| 520 | .intermediate_rate = 64000, |
| 521 | .user_data_chunk_bits = 48, |
| 522 | .adapt_user_to_ir = v110_adapt_Nx4800_to_IR, |
| 523 | .adapt_ir_to_user = v110_adapt_IR_to_Nx4800, |
| 524 | }, |
| 525 | }; |
| 526 | |
| 527 | /*! obtain the size (in number of bits) of the user data bits in one V.110 |
| 528 | * frame for specified RA1 rate */ |
| 529 | int osmo_v110_sync_ra1_get_user_data_chunk_bitlen(enum osmo_v100_sync_ra1_rate rate) |
| 530 | { |
| 531 | if (rate < 0 || rate >= _NUM_OSMO_V110_SYNC_RA1) |
| 532 | return -EINVAL; |
| 533 | |
| 534 | return osmo_v110_sync_ra1_def[rate].user_data_chunk_bits; |
| 535 | } |
| 536 | |
| 537 | /*! obtain the user data rate (in bits/s) for specified RA1 rate */ |
| 538 | int osmo_v110_sync_ra1_get_user_data_rate(enum osmo_v100_sync_ra1_rate rate) |
| 539 | { |
| 540 | if (rate < 0 || rate >= _NUM_OSMO_V110_SYNC_RA1) |
| 541 | return -EINVAL; |
| 542 | |
| 543 | return osmo_v110_sync_ra1_def[rate].data_rate; |
| 544 | } |
| 545 | |
| 546 | /*! obtain the intermediate rate (in bits/s) for specified RA1 rate */ |
| 547 | int osmo_v110_sync_ra1_get_intermediate_rate(enum osmo_v100_sync_ra1_rate rate) |
| 548 | { |
| 549 | if (rate < 0 || rate >= _NUM_OSMO_V110_SYNC_RA1) |
| 550 | return -EINVAL; |
| 551 | |
| 552 | return osmo_v110_sync_ra1_def[rate].intermediate_rate; |
| 553 | } |
| 554 | |
| 555 | /*! perform V.110 RA1 function in user rate -> intermediate rate direction. |
| 556 | * \param[in] rate specification of the user bitrate |
| 557 | * \param[out] fr caller-allocated output buffer for the [decoded] V.110 frame generated |
| 558 | * \param[in] d_in input user data (unpacked bits) |
| 559 | * \param[in] in_len length of user input data (in number of bits) |
| 560 | * \returns 0 on success; negative in case of error */ |
| 561 | int osmo_v110_sync_ra1_user_to_ir(enum osmo_v100_sync_ra1_rate rate, struct osmo_v110_decoded_frame *fr, |
| 562 | const ubit_t *d_in, size_t in_len) |
| 563 | { |
| 564 | if (rate < 0 || rate >= _NUM_OSMO_V110_SYNC_RA1) |
| 565 | return -EINVAL; |
| 566 | |
| 567 | return osmo_v110_sync_ra1_def[rate].adapt_user_to_ir(fr, d_in, in_len); |
| 568 | } |
| 569 | |
| 570 | /*! perform V.110 RA1 function in intermediate rate -> user rate direction. |
| 571 | * \param[in] rate specification of the user bitrate |
| 572 | * \param[out] d_out caller-allocated output user data (unpacked bits) |
| 573 | * \param[out] out_len length of d_out output buffer |
| 574 | * \param[in] fr [decoded] V.110 frame used as input |
| 575 | * \returns number of unpacked bits written to d_out on success; negative in case of error */ |
| 576 | int osmo_v110_sync_ra1_ir_to_user(enum osmo_v100_sync_ra1_rate rate, ubit_t *d_out, size_t out_len, |
| 577 | const struct osmo_v110_decoded_frame *fr) |
| 578 | { |
| 579 | if (rate < 0 || rate >= _NUM_OSMO_V110_SYNC_RA1) |
| 580 | return -EINVAL; |
| 581 | |
| 582 | return osmo_v110_sync_ra1_def[rate].adapt_ir_to_user(d_out, out_len, fr); |
| 583 | } |