sys/dev/sound/pcm/feeder_rate.c

   1 /*-
   2  * Copyright (c) 2005-2009 Ariff Abdullah <ariff@FreeBSD.org>
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  24  * SUCH DAMAGE.
  25  */
  26
  27 /*
  28  * feeder_rate: (Codename: Z Resampler), which means any effort to create
  29  *              future replacement for this resampler are simply absurd unless
  30  *              the world decide to add new alphabet after Z.
  31  *
  32  * FreeBSD bandlimited sinc interpolator, technically based on
  33  * "Digital Audio Resampling" by Julius O. Smith III
  34  *  - http://ccrma.stanford.edu/~jos/resample/
  35  *
  36  * The Good:
  37  * + all out fixed point integer operations, no soft-float or anything like
  38  *   that.
  39  * + classic polyphase converters with high quality coefficient's polynomial
  40  *   interpolators.
  41  * + fast, faster, or the fastest of its kind.
  42  * + compile time configurable.
  43  * + etc etc..
  44  *
  45  * The Bad:
  46  * - The z, z_, and Z_ . Due to mental block (or maybe just 0x7a69), I
  47  *   couldn't think of anything simpler than that (feeder_rate_xxx is just
  48  *   too long). Expect possible clashes with other zitizens (any?).
  49  */
  50
  51 #ifdef _KERNEL
  52 #ifdef HAVE_KERNEL_OPTION_HEADERS
  53 #include "opt_snd.h"
  54 #endif
  55 #include <dev/sound/pcm/sound.h>
  56 #include <dev/sound/pcm/pcm.h>
  57 #include "feeder_if.h"
  58
  59 #define SND_USE_FXDIV
  60 #include "snd_fxdiv_gen.h"
  61
  62 SND_DECLARE_FILE("$FreeBSD: head/sys/dev/sound/pcm/feeder_rate.c 267992 2014-06-28 03:56:17Z hselasky $");
  63 #endif
  64
  65 #include "feeder_rate_gen.h"
  66
  67 #if !defined(_KERNEL) && defined(SND_DIAGNOSTIC)
  68 #undef Z_DIAGNOSTIC
  69 #define Z_DIAGNOSTIC            1
  70 #elif defined(_KERNEL)
  71 #undef Z_DIAGNOSTIC
  72 #endif
  73
  74 #ifndef Z_QUALITY_DEFAULT
  75 #define Z_QUALITY_DEFAULT       Z_QUALITY_LINEAR
  76 #endif
  77
  78 #define Z_RESERVOIR             2048
  79 #define Z_RESERVOIR_MAX         131072
  80
  81 #define Z_SINC_MAX              0x3fffff
  82 #define Z_SINC_DOWNMAX          48              /* 384000 / 8000 */
  83
  84 #ifdef _KERNEL
  85 #define Z_POLYPHASE_MAX         183040          /* 286 taps, 640 phases */
  86 #else
  87 #define Z_POLYPHASE_MAX         1464320         /* 286 taps, 5120 phases */
  88 #endif
  89
  90 #define Z_RATE_DEFAULT          48000
  91
  92 #define Z_RATE_MIN              FEEDRATE_RATEMIN
  93 #define Z_RATE_MAX              FEEDRATE_RATEMAX
  94 #define Z_ROUNDHZ               FEEDRATE_ROUNDHZ
  95 #define Z_ROUNDHZ_MIN           FEEDRATE_ROUNDHZ_MIN
  96 #define Z_ROUNDHZ_MAX           FEEDRATE_ROUNDHZ_MAX
  97
  98 #define Z_RATE_SRC              FEEDRATE_SRC
  99 #define Z_RATE_DST              FEEDRATE_DST
 100 #define Z_RATE_QUALITY          FEEDRATE_QUALITY
 101 #define Z_RATE_CHANNELS         FEEDRATE_CHANNELS
 102
 103 #define Z_PARANOID              1
 104
 105 #define Z_MULTIFORMAT           1
 106
 107 #ifdef _KERNEL
 108 #undef Z_USE_ALPHADRIFT
 109 #define Z_USE_ALPHADRIFT        1
 110 #endif
 111
 112 #define Z_FACTOR_MIN            1
 113 #define Z_FACTOR_MAX            Z_MASK
 114 #define Z_FACTOR_SAFE(v)        (!((v) < Z_FACTOR_MIN || (v) > Z_FACTOR_MAX))
 115
 116 struct z_info;
 117
 118 typedef void (*z_resampler_t)(struct z_info *, uint8_t *);
 119
 120 struct z_info {
 121         int32_t rsrc, rdst;     /* original source / destination rates */
 122         int32_t src, dst;       /* rounded source / destination rates */
 123         int32_t channels;       /* total channels */
 124         int32_t bps;            /* bytes-per-sample */
 125         int32_t quality;        /* resampling quality */
 126
 127         int32_t z_gx, z_gy;     /* interpolation / decimation ratio */
 128         int32_t z_alpha;        /* output sample time phase / drift */
 129         uint8_t *z_delay;       /* FIR delay line / linear buffer */
 130         int32_t *z_coeff;       /* FIR coefficients */
 131         int32_t *z_dcoeff;      /* FIR coefficients differences */
 132         int32_t *z_pcoeff;      /* FIR polyphase coefficients */
 133         int32_t z_scale;        /* output scaling */
 134         int32_t z_dx;           /* input sample drift increment */
 135         int32_t z_dy;           /* output sample drift increment */
 136 #ifdef Z_USE_ALPHADRIFT
 137         int32_t z_alphadrift;   /* alpha drift rate */
 138         int32_t z_startdrift;   /* buffer start position drift rate */
 139 #endif
 140         int32_t z_mask;         /* delay line full length mask */
 141         int32_t z_size;         /* half width of FIR taps */
 142         int32_t z_full;         /* full size of delay line */
 143         int32_t z_alloc;        /* largest allocated full size of delay line */
 144         int32_t z_start;        /* buffer processing start position */
 145         int32_t z_pos;          /* current position for the next feed */
 146 #ifdef Z_DIAGNOSTIC
 147         uint32_t z_cycle;       /* output cycle, purely for statistical */
 148 #endif
 149         int32_t z_maxfeed;      /* maximum feed to avoid 32bit overflow */
 150
 151         z_resampler_t z_resample;
 152 };
 153
 154 int feeder_rate_min = Z_RATE_MIN;
 155 int feeder_rate_max = Z_RATE_MAX;
 156 int feeder_rate_round = Z_ROUNDHZ;
 157 int feeder_rate_quality = Z_QUALITY_DEFAULT;
 158
 159 static int feeder_rate_polyphase_max = Z_POLYPHASE_MAX;
 160
 161 #ifdef _KERNEL
 162 static char feeder_rate_presets[] = FEEDER_RATE_PRESETS;
 163 SYSCTL_STRING(_hw_snd, OID_AUTO, feeder_rate_presets, CTLFLAG_RD,
 164     &feeder_rate_presets, 0, "compile-time rate presets");
 165
 166 TUNABLE_INT("hw.snd.feeder_rate_min", &feeder_rate_min);
 167 TUNABLE_INT("hw.snd.feeder_rate_max", &feeder_rate_max);
 168 TUNABLE_INT("hw.snd.feeder_rate_round", &feeder_rate_round);
 169 TUNABLE_INT("hw.snd.feeder_rate_quality", &feeder_rate_quality);
 170
 171 SYSCTL_INT(_hw_snd, OID_AUTO, feeder_rate_polyphase_max, CTLFLAG_RWTUN,
 172     &feeder_rate_polyphase_max, 0, "maximum allowable polyphase entries");
 173
 174 static int
 175 sysctl_hw_snd_feeder_rate_min(SYSCTL_HANDLER_ARGS)
 176 {
 177         int err, val;
 178
 179         val = feeder_rate_min;
 180         err = sysctl_handle_int(oidp, &val, 0, req);
 181
 182         if (err != 0 || req->newptr == NULL || val == feeder_rate_min)
 183                 return (err);
 184
 185         if (!(Z_FACTOR_SAFE(val) && val < feeder_rate_max))
 186                 return (EINVAL);
 187
 188         feeder_rate_min = val;
 189
 190         return (0);
 191 }
 192 SYSCTL_PROC(_hw_snd, OID_AUTO, feeder_rate_min, CTLTYPE_INT | CTLFLAG_RW,
 193     0, sizeof(int), sysctl_hw_snd_feeder_rate_min, "I",
 194     "minimum allowable rate");
 195
 196 static int
 197 sysctl_hw_snd_feeder_rate_max(SYSCTL_HANDLER_ARGS)
 198 {
 199         int err, val;
 200
 201         val = feeder_rate_max;
 202         err = sysctl_handle_int(oidp, &val, 0, req);
 203
 204         if (err != 0 || req->newptr == NULL || val == feeder_rate_max)
 205                 return (err);
 206
 207         if (!(Z_FACTOR_SAFE(val) && val > feeder_rate_min))
 208                 return (EINVAL);
 209
 210         feeder_rate_max = val;
 211
 212         return (0);
 213 }
 214 SYSCTL_PROC(_hw_snd, OID_AUTO, feeder_rate_max, CTLTYPE_INT | CTLFLAG_RW,
 215     0, sizeof(int), sysctl_hw_snd_feeder_rate_max, "I",
 216     "maximum allowable rate");
 217
 218 static int
 219 sysctl_hw_snd_feeder_rate_round(SYSCTL_HANDLER_ARGS)
 220 {
 221         int err, val;
 222
 223         val = feeder_rate_round;
 224         err = sysctl_handle_int(oidp, &val, 0, req);
 225
 226         if (err != 0 || req->newptr == NULL || val == feeder_rate_round)
 227                 return (err);
 228
 229         if (val < Z_ROUNDHZ_MIN || val > Z_ROUNDHZ_MAX)
 230                 return (EINVAL);
 231
 232         feeder_rate_round = val - (val % Z_ROUNDHZ);
 233
 234         return (0);
 235 }
 236 SYSCTL_PROC(_hw_snd, OID_AUTO, feeder_rate_round, CTLTYPE_INT | CTLFLAG_RW,
 237     0, sizeof(int), sysctl_hw_snd_feeder_rate_round, "I",
 238     "sample rate converter rounding threshold");
 239
 240 static int
 241 sysctl_hw_snd_feeder_rate_quality(SYSCTL_HANDLER_ARGS)
 242 {
 243         struct snddev_info *d;
 244         struct pcm_channel *c;
 245         struct pcm_feeder *f;
 246         int i, err, val;
 247
 248         val = feeder_rate_quality;
 249         err = sysctl_handle_int(oidp, &val, 0, req);
 250
 251         if (err != 0 || req->newptr == NULL || val == feeder_rate_quality)
 252                 return (err);
 253
 254         if (val < Z_QUALITY_MIN || val > Z_QUALITY_MAX)
 255                 return (EINVAL);
 256
 257         feeder_rate_quality = val;
 258
 259         /*
 260          * Traverse all available channels on each device and try to
 261          * set resampler quality if and only if it is exist as
 262          * part of feeder chains and the channel is idle.
 263          */
 264         for (i = 0; pcm_devclass != NULL &&
 265             i < devclass_get_maxunit(pcm_devclass); i++) {
 266                 d = devclass_get_softc(pcm_devclass, i);
 267                 if (!PCM_REGISTERED(d))
 268                         continue;
 269                 PCM_LOCK(d);
 270                 PCM_WAIT(d);
 271                 PCM_ACQUIRE(d);
 272                 CHN_FOREACH(c, d, channels.pcm) {
 273                         CHN_LOCK(c);
 274                         f = chn_findfeeder(c, FEEDER_RATE);
 275                         if (f == NULL || f->data == NULL || CHN_STARTED(c)) {
 276                                 CHN_UNLOCK(c);
 277                                 continue;
 278                         }
 279                         (void)FEEDER_SET(f, FEEDRATE_QUALITY, val);
 280                         CHN_UNLOCK(c);
 281                 }
 282                 PCM_RELEASE(d);
 283                 PCM_UNLOCK(d);
 284         }
 285
 286         return (0);
 287 }
 288 SYSCTL_PROC(_hw_snd, OID_AUTO, feeder_rate_quality, CTLTYPE_INT | CTLFLAG_RW,
 289     0, sizeof(int), sysctl_hw_snd_feeder_rate_quality, "I",
 290     "sample rate converter quality ("__XSTRING(Z_QUALITY_MIN)"=low .. "
 291     __XSTRING(Z_QUALITY_MAX)"=high)");
 292 #endif  /* _KERNEL */
 293
 294
 295 /*
 296  * Resampler type.
 297  */
 298 #define Z_IS_ZOH(i)             ((i)->quality == Z_QUALITY_ZOH)
 299 #define Z_IS_LINEAR(i)          ((i)->quality == Z_QUALITY_LINEAR)
 300 #define Z_IS_SINC(i)            ((i)->quality > Z_QUALITY_LINEAR)
 301
 302 /*
 303  * Macroses for accurate sample time drift calculations.
 304  *
 305  * gy2gx : given the amount of output, return the _exact_ required amount of
 306  *         input.
 307  * gx2gy : given the amount of input, return the _maximum_ amount of output
 308  *         that will be generated.
 309  * drift : given the amount of input and output, return the elapsed
 310  *         sample-time.
 311  */
 312 #define _Z_GCAST(x)             ((uint64_t)(x))
 313
 314 #if defined(__GNUCLIKE_ASM) && defined(__i386__)
 315 /*
 316  * This is where i386 being beaten to a pulp. Fortunately this function is
 317  * rarely being called and if it is, it will decide the best (hopefully)
 318  * fastest way to do the division. If we can ensure that everything is dword
 319  * aligned, letting the compiler to call udivdi3 to do the division can be
 320  * faster compared to this.
 321  *
 322  * amd64 is the clear winner here, no question about it.
 323  */
 324 static __inline uint32_t
 325 Z_DIV(uint64_t v, uint32_t d)
 326 {
 327         uint32_t hi, lo, quo, rem;
 328
 329         hi = v >> 32;
 330         lo = v & 0xffffffff;
 331
 332         /*
 333          * As much as we can, try to avoid long division like a plague.
 334          */
 335         if (hi == 0)
 336                 quo = lo / d;
 337         else
 338                 __asm("divl %2"
 339                     : "=a" (quo), "=d" (rem)
 340                     : "r" (d), "0" (lo), "1" (hi));
 341
 342         return (quo);
 343 }
 344 #else
 345 #define Z_DIV(x, y)             ((x) / (y))
 346 #endif
 347
 348 #define _Z_GY2GX(i, a, v)                                               \
 349         Z_DIV(((_Z_GCAST((i)->z_gx) * (v)) + ((i)->z_gy - (a) - 1)),    \
 350         (i)->z_gy)
 351
 352 #define _Z_GX2GY(i, a, v)                                               \
 353         Z_DIV(((_Z_GCAST((i)->z_gy) * (v)) + (a)), (i)->z_gx)
 354
 355 #define _Z_DRIFT(i, x, y)                                               \
 356         ((_Z_GCAST((i)->z_gy) * (x)) - (_Z_GCAST((i)->z_gx) * (y)))
 357
 358 #define z_gy2gx(i, v)           _Z_GY2GX(i, (i)->z_alpha, v)
 359 #define z_gx2gy(i, v)           _Z_GX2GY(i, (i)->z_alpha, v)
 360 #define z_drift(i, x, y)        _Z_DRIFT(i, x, y)
 361
 362 /*
 363  * Macroses for SINC coefficients table manipulations.. whatever.
 364  */
 365 #define Z_SINC_COEFF_IDX(i)     ((i)->quality - Z_QUALITY_LINEAR - 1)
 366
 367 #define Z_SINC_LEN(i)                                                   \
 368         ((int32_t)(((uint64_t)z_coeff_tab[Z_SINC_COEFF_IDX(i)].len <<   \
 369             Z_SHIFT) / (i)->z_dy))
 370
 371 #define Z_SINC_BASE_LEN(i)                                              \
 372         ((z_coeff_tab[Z_SINC_COEFF_IDX(i)].len - 1) >> (Z_DRIFT_SHIFT - 1))
 373
 374 /*
 375  * Macroses for linear delay buffer operations. Alignment is not
 376  * really necessary since we're not using true circular buffer, but it
 377  * will help us guard against possible trespasser. To be honest,
 378  * the linear block operations does not need guarding at all due to
 379  * accurate drifting!
 380  */
 381 #define z_align(i, v)           ((v) & (i)->z_mask)
 382 #define z_next(i, o, v)         z_align(i, (o) + (v))
 383 #define z_prev(i, o, v)         z_align(i, (o) - (v))
 384 #define z_fetched(i)            (z_align(i, (i)->z_pos - (i)->z_start) - 1)
 385 #define z_free(i)               ((i)->z_full - (i)->z_pos)
 386
 387 /*
 388  * Macroses for Bla Bla .. :)
 389  */
 390 #define z_copy(src, dst, sz)    (void)memcpy(dst, src, sz)
 391 #define z_feed(...)             FEEDER_FEED(__VA_ARGS__)
 392
 393 static __inline uint32_t
 394 z_min(uint32_t x, uint32_t y)
 395 {
 396
 397         return ((x < y) ? x : y);
 398 }
 399
 400 static int32_t
 401 z_gcd(int32_t x, int32_t y)
 402 {
 403         int32_t w;
 404
 405         while (y != 0) {
 406                 w = x % y;
 407                 x = y;
 408                 y = w;
 409         }
 410
 411         return (x);
 412 }
 413
 414 static int32_t
 415 z_roundpow2(int32_t v)
 416 {
 417         int32_t i;
 418
 419         i = 1;
 420
 421         /*
 422          * Let it overflow at will..
 423          */
 424         while (i > 0 && i < v)
 425                 i <<= 1;
 426
 427         return (i);
 428 }
 429
 430 /*
 431  * Zero Order Hold, the worst of the worst, an insult against quality,
 432  * but super fast.
 433  */
 434 static void
 435 z_feed_zoh(struct z_info *info, uint8_t *dst)
 436 {
 437 #if 0
 438         z_copy(info->z_delay +
 439             (info->z_start * info->channels * info->bps), dst,
 440             info->channels * info->bps);
 441 #else
 442         uint32_t cnt;
 443         uint8_t *src;
 444
 445         cnt = info->channels * info->bps;
 446         src = info->z_delay + (info->z_start * cnt);
 447
 448         /*
 449          * This is a bit faster than doing bcopy() since we're dealing
 450          * with possible unaligned samples.
 451          */
 452         do {
 453                 *dst++ = *src++;
 454         } while (--cnt != 0);
 455 #endif
 456 }
 457
 458 /*
 459  * Linear Interpolation. This at least sounds better (perceptually) and fast,
 460  * but without any proper filtering which means aliasing still exist and
 461  * could become worst with a right sample. Interpolation centered within
 462  * Z_LINEAR_ONE between the present and previous sample and everything is
 463  * done with simple 32bit scaling arithmetic.
 464  */
 465 #define Z_DECLARE_LINEAR(SIGN, BIT, ENDIAN)                                     \
 466 static void                                                                     \
 467 z_feed_linear_##SIGN##BIT##ENDIAN(struct z_info *info, uint8_t *dst)            \
 468 {                                                                               \
 469         int32_t z;                                                              \
 470         intpcm_t x, y;                                                          \
 471         uint32_t ch;                                                            \
 472         uint8_t *sx, *sy;                                                       \
 473                                                                                 \
 474         z = ((uint32_t)info->z_alpha * info->z_dx) >> Z_LINEAR_UNSHIFT;         \
 475                                                                                 \
 476         sx = info->z_delay + (info->z_start * info->channels *                  \
 477             PCM_##BIT##_BPS);                                                   \
 478         sy = sx - (info->channels * PCM_##BIT##_BPS);                           \
 479                                                                                 \
 480         ch = info->channels;                                                    \
 481                                                                                 \
 482         do {                                                                    \
 483                 x = _PCM_READ_##SIGN##BIT##_##ENDIAN(sx);                       \
 484                 y = _PCM_READ_##SIGN##BIT##_##ENDIAN(sy);                       \
 485                 x = Z_LINEAR_INTERPOLATE_##BIT(z, x, y);                        \
 486                 _PCM_WRITE_##SIGN##BIT##_##ENDIAN(dst, x);                      \
 487                 sx += PCM_##BIT##_BPS;                                          \
 488                 sy += PCM_##BIT##_BPS;                                          \
 489                 dst += PCM_##BIT##_BPS;                                         \
 490         } while (--ch != 0);                                                    \
 491 }
 492
 493 /*
 494  * Userland clipping diagnostic check, not enabled in kernel compilation.
 495  * While doing sinc interpolation, unrealistic samples like full scale sine
 496  * wav will clip, but for other things this will not make any noise at all.
 497  * Everybody should learn how to normalized perceived loudness of their own
 498  * music/sounds/samples (hint: ReplayGain).
 499  */
 500 #ifdef Z_DIAGNOSTIC
 501 #define Z_CLIP_CHECK(v, BIT)    do {                                    \
 502         if ((v) > PCM_S##BIT##_MAX) {                                   \
 503                 fprintf(stderr, "Overflow: v=%jd, max=%jd\n",           \
 504                     (intmax_t)(v), (intmax_t)PCM_S##BIT##_MAX);         \
 505         } else if ((v) < PCM_S##BIT##_MIN) {                            \
 506                 fprintf(stderr, "Underflow: v=%jd, min=%jd\n",          \
 507                     (intmax_t)(v), (intmax_t)PCM_S##BIT##_MIN);         \
 508         }                                                               \
 509 } while (0)
 510 #else
 511 #define Z_CLIP_CHECK(...)
 512 #endif
 513
 514 #define Z_CLAMP(v, BIT)                                                 \
 515         (((v) > PCM_S##BIT##_MAX) ? PCM_S##BIT##_MAX :                  \
 516         (((v) < PCM_S##BIT##_MIN) ? PCM_S##BIT##_MIN : (v)))
 517
 518 /*
 519  * Sine Cardinal (SINC) Interpolation. Scaling is done in 64 bit, so
 520  * there's no point to hold the plate any longer. All samples will be
 521  * shifted to a full 32 bit, scaled and restored during write for
 522  * maximum dynamic range (only for downsampling).
 523  */
 524 #define _Z_SINC_ACCUMULATE(SIGN, BIT, ENDIAN, adv)                      \
 525         c += z >> Z_SHIFT;                                              \
 526         z &= Z_MASK;                                                    \
 527         coeff = Z_COEFF_INTERPOLATE(z, z_coeff[c], z_dcoeff[c]);        \
 528         x = _PCM_READ_##SIGN##BIT##_##ENDIAN(p);                        \
 529         v += Z_NORM_##BIT((intpcm64_t)x * coeff);                       \
 530         z += info->z_dy;                                                \
 531         p adv##= info->channels * PCM_##BIT##_BPS
 532
 533 /*
 534  * XXX GCC4 optimization is such a !@#$%, need manual unrolling.
 535  */
 536 #if defined(__GNUC__) && __GNUC__ >= 4
 537 #define Z_SINC_ACCUMULATE(...)  do {                                    \
 538         _Z_SINC_ACCUMULATE(__VA_ARGS__);                                \
 539         _Z_SINC_ACCUMULATE(__VA_ARGS__);                                \
 540 } while (0)
 541 #define Z_SINC_ACCUMULATE_DECR          2
 542 #else
 543 #define Z_SINC_ACCUMULATE(...)  do {                                    \
 544         _Z_SINC_ACCUMULATE(__VA_ARGS__);                                \
 545 } while (0)
 546 #define Z_SINC_ACCUMULATE_DECR          1
 547 #endif
 548
 549 #define Z_DECLARE_SINC(SIGN, BIT, ENDIAN)                                       \
 550 static void                                                                     \
 551 z_feed_sinc_##SIGN##BIT##ENDIAN(struct z_info *info, uint8_t *dst)              \
 552 {                                                                               \
 553         intpcm64_t v;                                                           \
 554         intpcm_t x;                                                             \
 555         uint8_t *p;                                                             \
 556         int32_t coeff, z, *z_coeff, *z_dcoeff;                                  \
 557         uint32_t c, center, ch, i;                                              \
 558                                                                                 \
 559         z_coeff = info->z_coeff;                                                \
 560         z_dcoeff = info->z_dcoeff;                                              \
 561         center = z_prev(info, info->z_start, info->z_size);                     \
 562         ch = info->channels * PCM_##BIT##_BPS;                                  \
 563         dst += ch;                                                              \
 564                                                                                 \
 565         do {                                                                    \
 566                 dst -= PCM_##BIT##_BPS;                                         \
 567                 ch -= PCM_##BIT##_BPS;                                          \
 568                 v = 0;                                                          \
 569                 z = info->z_alpha * info->z_dx;                                 \
 570                 c = 0;                                                          \
 571                 p = info->z_delay + (z_next(info, center, 1) *                  \
 572                     info->channels * PCM_##BIT##_BPS) + ch;                     \
 573                 for (i = info->z_size; i != 0; i -= Z_SINC_ACCUMULATE_DECR)     \
 574                         Z_SINC_ACCUMULATE(SIGN, BIT, ENDIAN, +);                \
 575                 z = info->z_dy - (info->z_alpha * info->z_dx);                  \
 576                 c = 0;                                                          \
 577                 p = info->z_delay + (center * info->channels *                  \
 578                     PCM_##BIT##_BPS) + ch;                                      \
 579                 for (i = info->z_size; i != 0; i -= Z_SINC_ACCUMULATE_DECR)     \
 580                         Z_SINC_ACCUMULATE(SIGN, BIT, ENDIAN, -);                \
 581                 if (info->z_scale != Z_ONE)                                     \
 582                         v = Z_SCALE_##BIT(v, info->z_scale);                    \
 583                 else                                                            \
 584                         v >>= Z_COEFF_SHIFT - Z_GUARD_BIT_##BIT;                \
 585                 Z_CLIP_CHECK(v, BIT);                                           \
 586                 _PCM_WRITE_##SIGN##BIT##_##ENDIAN(dst, Z_CLAMP(v, BIT));        \
 587         } while (ch != 0);                                                      \
 588 }
 589
 590 #define Z_DECLARE_SINC_POLYPHASE(SIGN, BIT, ENDIAN)                             \
 591 static void                                                                     \
 592 z_feed_sinc_polyphase_##SIGN##BIT##ENDIAN(struct z_info *info, uint8_t *dst)    \
 593 {                                                                               \
 594         intpcm64_t v;                                                           \
 595         intpcm_t x;                                                             \
 596         uint8_t *p;                                                             \
 597         int32_t ch, i, start, *z_pcoeff;                                        \
 598                                                                                 \
 599         ch = info->channels * PCM_##BIT##_BPS;                                  \
 600         dst += ch;                                                              \
 601         start = z_prev(info, info->z_start, (info->z_size << 1) - 1) * ch;      \
 602                                                                                 \
 603         do {                                                                    \
 604                 dst -= PCM_##BIT##_BPS;                                         \
 605                 ch -= PCM_##BIT##_BPS;                                          \
 606                 v = 0;                                                          \
 607                 p = info->z_delay + start + ch;                                 \
 608                 z_pcoeff = info->z_pcoeff +                                     \
 609                     ((info->z_alpha * info->z_size) << 1);                      \
 610                 for (i = info->z_size; i != 0; i--) {                           \
 611                         x = _PCM_READ_##SIGN##BIT##_##ENDIAN(p);                \
 612                         v += Z_NORM_##BIT((intpcm64_t)x * *z_pcoeff);           \
 613                         z_pcoeff++;                                             \
 614                         p += info->channels * PCM_##BIT##_BPS;                  \
 615                         x = _PCM_READ_##SIGN##BIT##_##ENDIAN(p);                \
 616                         v += Z_NORM_##BIT((intpcm64_t)x * *z_pcoeff);           \
 617                         z_pcoeff++;                                             \
 618                         p += info->channels * PCM_##BIT##_BPS;                  \
 619                 }                                                               \
 620                 if (info->z_scale != Z_ONE)                                     \
 621                         v = Z_SCALE_##BIT(v, info->z_scale);                    \
 622                 else                                                            \
 623                         v >>= Z_COEFF_SHIFT - Z_GUARD_BIT_##BIT;                \
 624                 Z_CLIP_CHECK(v, BIT);                                           \
 625                 _PCM_WRITE_##SIGN##BIT##_##ENDIAN(dst, Z_CLAMP(v, BIT));        \
 626         } while (ch != 0);                                                      \
 627 }
 628
 629 #define Z_DECLARE(SIGN, BIT, ENDIAN)                                    \
 630         Z_DECLARE_LINEAR(SIGN, BIT, ENDIAN)                             \
 631         Z_DECLARE_SINC(SIGN, BIT, ENDIAN)                               \
 632         Z_DECLARE_SINC_POLYPHASE(SIGN, BIT, ENDIAN)
 633
 634 #if BYTE_ORDER == LITTLE_ENDIAN || defined(SND_FEEDER_MULTIFORMAT)
 635 Z_DECLARE(S, 16, LE)
 636 Z_DECLARE(S, 32, LE)
 637 #endif
 638 #if BYTE_ORDER == BIG_ENDIAN || defined(SND_FEEDER_MULTIFORMAT)
 639 Z_DECLARE(S, 16, BE)
 640 Z_DECLARE(S, 32, BE)
 641 #endif
 642 #ifdef SND_FEEDER_MULTIFORMAT
 643 Z_DECLARE(S,  8, NE)
 644 Z_DECLARE(S, 24, LE)
 645 Z_DECLARE(S, 24, BE)
 646 Z_DECLARE(U,  8, NE)
 647 Z_DECLARE(U, 16, LE)
 648 Z_DECLARE(U, 24, LE)
 649 Z_DECLARE(U, 32, LE)
 650 Z_DECLARE(U, 16, BE)
 651 Z_DECLARE(U, 24, BE)
 652 Z_DECLARE(U, 32, BE)
 653 #endif
 654
 655 enum {
 656         Z_RESAMPLER_ZOH,
 657         Z_RESAMPLER_LINEAR,
 658         Z_RESAMPLER_SINC,
 659         Z_RESAMPLER_SINC_POLYPHASE,
 660         Z_RESAMPLER_LAST
 661 };
 662
 663 #define Z_RESAMPLER_IDX(i)                                              \
 664         (Z_IS_SINC(i) ? Z_RESAMPLER_SINC : (i)->quality)
 665
 666 #define Z_RESAMPLER_ENTRY(SIGN, BIT, ENDIAN)                                    \
 667         {                                                                       \
 668             AFMT_##SIGN##BIT##_##ENDIAN,                                        \
 669             {                                                                   \
 670                 [Z_RESAMPLER_ZOH]    = z_feed_zoh,                              \
 671                 [Z_RESAMPLER_LINEAR] = z_feed_linear_##SIGN##BIT##ENDIAN,       \
 672                 [Z_RESAMPLER_SINC]   = z_feed_sinc_##SIGN##BIT##ENDIAN,         \
 673                 [Z_RESAMPLER_SINC_POLYPHASE]   =                                \
 674                     z_feed_sinc_polyphase_##SIGN##BIT##ENDIAN                   \
 675             }                                                                   \
 676         }
 677
 678 static const struct {
 679         uint32_t format;
 680         z_resampler_t resampler[Z_RESAMPLER_LAST];
 681 } z_resampler_tab[] = {
 682 #if BYTE_ORDER == LITTLE_ENDIAN || defined(SND_FEEDER_MULTIFORMAT)
 683         Z_RESAMPLER_ENTRY(S, 16, LE),
 684         Z_RESAMPLER_ENTRY(S, 32, LE),
 685 #endif
 686 #if BYTE_ORDER == BIG_ENDIAN || defined(SND_FEEDER_MULTIFORMAT)
 687         Z_RESAMPLER_ENTRY(S, 16, BE),
 688         Z_RESAMPLER_ENTRY(S, 32, BE),
 689 #endif
 690 #ifdef SND_FEEDER_MULTIFORMAT
 691         Z_RESAMPLER_ENTRY(S,  8, NE),
 692         Z_RESAMPLER_ENTRY(S, 24, LE),
 693         Z_RESAMPLER_ENTRY(S, 24, BE),
 694         Z_RESAMPLER_ENTRY(U,  8, NE),
 695         Z_RESAMPLER_ENTRY(U, 16, LE),
 696         Z_RESAMPLER_ENTRY(U, 24, LE),
 697         Z_RESAMPLER_ENTRY(U, 32, LE),
 698         Z_RESAMPLER_ENTRY(U, 16, BE),
 699         Z_RESAMPLER_ENTRY(U, 24, BE),
 700         Z_RESAMPLER_ENTRY(U, 32, BE),
 701 #endif
 702 };
 703
 704 #define Z_RESAMPLER_TAB_SIZE                                            \
 705         ((int32_t)(sizeof(z_resampler_tab) / sizeof(z_resampler_tab[0])))
 706
 707 static void
 708 z_resampler_reset(struct z_info *info)
 709 {
 710
 711         info->src = info->rsrc - (info->rsrc % ((feeder_rate_round > 0 &&
 712             info->rsrc > feeder_rate_round) ? feeder_rate_round : 1));
 713         info->dst = info->rdst - (info->rdst % ((feeder_rate_round > 0 &&
 714             info->rdst > feeder_rate_round) ? feeder_rate_round : 1));
 715         info->z_gx = 1;
 716         info->z_gy = 1;
 717         info->z_alpha = 0;
 718         info->z_resample = NULL;
 719         info->z_size = 1;
 720         info->z_coeff = NULL;
 721         info->z_dcoeff = NULL;
 722         if (info->z_pcoeff != NULL) {
 723                 free(info->z_pcoeff, M_DEVBUF);
 724                 info->z_pcoeff = NULL;
 725         }
 726         info->z_scale = Z_ONE;
 727         info->z_dx = Z_FULL_ONE;
 728         info->z_dy = Z_FULL_ONE;
 729 #ifdef Z_DIAGNOSTIC
 730         info->z_cycle = 0;
 731 #endif
 732         if (info->quality < Z_QUALITY_MIN)
 733                 info->quality = Z_QUALITY_MIN;
 734         else if (info->quality > Z_QUALITY_MAX)
 735                 info->quality = Z_QUALITY_MAX;
 736 }
 737
 738 #ifdef Z_PARANOID
 739 static int32_t
 740 z_resampler_sinc_len(struct z_info *info)
 741 {
 742         int32_t c, z, len, lmax;
 743
 744         if (!Z_IS_SINC(info))
 745                 return (1);
 746
 747         /*
 748          * A rather careful (or useless) way to calculate filter length.
 749          * Z_SINC_LEN() itself is accurate enough to do its job. Extra
 750          * sanity checking is not going to hurt though..
 751          */
 752         c = 0;
 753         z = info->z_dy;
 754         len = 0;
 755         lmax = z_coeff_tab[Z_SINC_COEFF_IDX(info)].len;
 756
 757         do {
 758                 c += z >> Z_SHIFT;
 759                 z &= Z_MASK;
 760                 z += info->z_dy;
 761         } while (c < lmax && ++len > 0);
 762
 763         if (len != Z_SINC_LEN(info)) {
 764 #ifdef _KERNEL
 765                 printf("%s(): sinc l=%d != Z_SINC_LEN=%d\n",
 766                     __func__, len, Z_SINC_LEN(info));
 767 #else
 768                 fprintf(stderr, "%s(): sinc l=%d != Z_SINC_LEN=%d\n",
 769                     __func__, len, Z_SINC_LEN(info));
 770                 return (-1);
 771 #endif
 772         }
 773
 774         return (len);
 775 }
 776 #else
 777 #define z_resampler_sinc_len(i)         (Z_IS_SINC(i) ? Z_SINC_LEN(i) : 1)
 778 #endif
 779
 780 #define Z_POLYPHASE_COEFF_SHIFT         0
 781
 782 /*
 783  * Pick suitable polynomial interpolators based on filter oversampled ratio
 784  * (2 ^ Z_DRIFT_SHIFT).
 785  */
 786 #if !(defined(Z_COEFF_INTERP_ZOH) || defined(Z_COEFF_INTERP_LINEAR) ||          \
 787     defined(Z_COEFF_INTERP_QUADRATIC) || defined(Z_COEFF_INTERP_HERMITE) ||     \
 788     defined(Z_COEFF_INTER_BSPLINE) || defined(Z_COEFF_INTERP_OPT32X) ||         \
 789     defined(Z_COEFF_INTERP_OPT16X) || defined(Z_COEFF_INTERP_OPT8X) ||          \
 790     defined(Z_COEFF_INTERP_OPT4X) || defined(Z_COEFF_INTERP_OPT2X))
 791 #if Z_DRIFT_SHIFT >= 6
 792 #define Z_COEFF_INTERP_BSPLINE          1
 793 #elif Z_DRIFT_SHIFT >= 5
 794 #define Z_COEFF_INTERP_OPT32X           1
 795 #elif Z_DRIFT_SHIFT == 4
 796 #define Z_COEFF_INTERP_OPT16X           1
 797 #elif Z_DRIFT_SHIFT == 3
 798 #define Z_COEFF_INTERP_OPT8X            1
 799 #elif Z_DRIFT_SHIFT == 2
 800 #define Z_COEFF_INTERP_OPT4X            1
 801 #elif Z_DRIFT_SHIFT == 1
 802 #define Z_COEFF_INTERP_OPT2X            1
 803 #else
 804 #error "Z_DRIFT_SHIFT screwed!"
 805 #endif
 806 #endif
 807
 808 /*
 809  * In classic polyphase mode, the actual coefficients for each phases need to
 810  * be calculated based on default prototype filters. For highly oversampled
 811  * filter, linear or quadradatic interpolator should be enough. Anything less
 812  * than that require 'special' interpolators to reduce interpolation errors.
 813  *
 814  * "Polynomial Interpolators for High-Quality Resampling of Oversampled Audio"
 815  *    by Olli Niemitalo
 816  *    - http://www.student.oulu.fi/~oniemita/dsp/deip.pdf
 817  *
 818  */
 819 static int32_t
 820 z_coeff_interpolate(int32_t z, int32_t *z_coeff)
 821 {
 822         int32_t coeff;
 823 #if defined(Z_COEFF_INTERP_ZOH)
 824
 825         /* 1-point, 0th-order (Zero Order Hold) */
 826         z = z;
 827         coeff = z_coeff[0];
 828 #elif defined(Z_COEFF_INTERP_LINEAR)
 829         int32_t zl0, zl1;
 830
 831         /* 2-point, 1st-order Linear */
 832         zl0 = z_coeff[0];
 833         zl1 = z_coeff[1] - z_coeff[0];
 834
 835         coeff = Z_RSHIFT((int64_t)zl1 * z, Z_SHIFT) + zl0;
 836 #elif defined(Z_COEFF_INTERP_QUADRATIC)
 837         int32_t zq0, zq1, zq2;
 838
 839         /* 3-point, 2nd-order Quadratic */
 840         zq0 = z_coeff[0];
 841         zq1 = z_coeff[1] - z_coeff[-1];
 842         zq2 = z_coeff[1] + z_coeff[-1] - (z_coeff[0] << 1);
 843
 844         coeff = Z_RSHIFT((Z_RSHIFT((int64_t)zq2 * z, Z_SHIFT) +
 845             zq1) * z, Z_SHIFT + 1) + zq0;
 846 #elif defined(Z_COEFF_INTERP_HERMITE)
 847         int32_t zh0, zh1, zh2, zh3;
 848
 849         /* 4-point, 3rd-order Hermite */
 850         zh0 = z_coeff[0];
 851         zh1 = z_coeff[1] - z_coeff[-1];
 852         zh2 = (z_coeff[-1] << 1) - (z_coeff[0] * 5) + (z_coeff[1] << 2) -
 853             z_coeff[2];
 854         zh3 = z_coeff[2] - z_coeff[-1] + ((z_coeff[0] - z_coeff[1]) * 3);
 855
 856         coeff = Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((int64_t)zh3 * z, Z_SHIFT) +
 857             zh2) * z, Z_SHIFT) + zh1) * z, Z_SHIFT + 1) + zh0;
 858 #elif defined(Z_COEFF_INTERP_BSPLINE)
 859         int32_t zb0, zb1, zb2, zb3;
 860
 861         /* 4-point, 3rd-order B-Spline */
 862         zb0 = Z_RSHIFT(0x15555555LL * (((int64_t)z_coeff[0] << 2) +
 863             z_coeff[-1] + z_coeff[1]), 30);
 864         zb1 = z_coeff[1] - z_coeff[-1];
 865         zb2 = z_coeff[-1] + z_coeff[1] - (z_coeff[0] << 1);
 866         zb3 = Z_RSHIFT(0x15555555LL * (((z_coeff[0] - z_coeff[1]) * 3) +
 867             z_coeff[2] - z_coeff[-1]), 30);
 868
 869         coeff = (Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((int64_t)zb3 * z, Z_SHIFT) +
 870             zb2) * z, Z_SHIFT) + zb1) * z, Z_SHIFT) + zb0 + 1) >> 1;
 871 #elif defined(Z_COEFF_INTERP_OPT32X)
 872         int32_t zoz, zoe1, zoe2, zoe3, zoo1, zoo2, zoo3;
 873         int32_t zoc0, zoc1, zoc2, zoc3, zoc4, zoc5;
 874
 875         /* 6-point, 5th-order Optimal 32x */
 876         zoz = z - (Z_ONE >> 1);
 877         zoe1 = z_coeff[1] + z_coeff[0];
 878         zoe2 = z_coeff[2] + z_coeff[-1];
 879         zoe3 = z_coeff[3] + z_coeff[-2];
 880         zoo1 = z_coeff[1] - z_coeff[0];
 881         zoo2 = z_coeff[2] - z_coeff[-1];
 882         zoo3 = z_coeff[3] - z_coeff[-2];
 883
 884         zoc0 = Z_RSHIFT((0x1ac2260dLL * zoe1) + (0x0526cdcaLL * zoe2) +
 885             (0x00170c29LL * zoe3), 30);
 886         zoc1 = Z_RSHIFT((0x14f8a49aLL * zoo1) + (0x0d6d1109LL * zoo2) +
 887             (0x008cd4dcLL * zoo3), 30);
 888         zoc2 = Z_RSHIFT((-0x0d3e94a4LL * zoe1) + (0x0bddded4LL * zoe2) +
 889             (0x0160b5d0LL * zoe3), 30);
 890         zoc3 = Z_RSHIFT((-0x0de10cc4LL * zoo1) + (0x019b2a7dLL * zoo2) +
 891             (0x01cfe914LL * zoo3), 30);
 892         zoc4 = Z_RSHIFT((0x02aa12d7LL * zoe1) + (-0x03ff1bb3LL * zoe2) +
 893             (0x015508ddLL * zoe3), 30);
 894         zoc5 = Z_RSHIFT((0x051d29e5LL * zoo1) + (-0x028e7647LL * zoo2) +
 895             (0x0082d81aLL * zoo3), 30);
 896
 897         coeff = Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT(
 898             (int64_t)zoc5 * zoz, Z_SHIFT) +
 899             zoc4) * zoz, Z_SHIFT) + zoc3) * zoz, Z_SHIFT) +
 900             zoc2) * zoz, Z_SHIFT) + zoc1) * zoz, Z_SHIFT) + zoc0;
 901 #elif defined(Z_COEFF_INTERP_OPT16X)
 902         int32_t zoz, zoe1, zoe2, zoe3, zoo1, zoo2, zoo3;
 903         int32_t zoc0, zoc1, zoc2, zoc3, zoc4, zoc5;
 904
 905         /* 6-point, 5th-order Optimal 16x */
 906         zoz = z - (Z_ONE >> 1);
 907         zoe1 = z_coeff[1] + z_coeff[0];
 908         zoe2 = z_coeff[2] + z_coeff[-1];
 909         zoe3 = z_coeff[3] + z_coeff[-2];
 910         zoo1 = z_coeff[1] - z_coeff[0];
 911         zoo2 = z_coeff[2] - z_coeff[-1];
 912         zoo3 = z_coeff[3] - z_coeff[-2];
 913
 914         zoc0 = Z_RSHIFT((0x1ac2260dLL * zoe1) + (0x0526cdcaLL * zoe2) +
 915             (0x00170c29LL * zoe3), 30);
 916         zoc1 = Z_RSHIFT((0x14f8a49aLL * zoo1) + (0x0d6d1109LL * zoo2) +
 917             (0x008cd4dcLL * zoo3), 30);
 918         zoc2 = Z_RSHIFT((-0x0d3e94a4LL * zoe1) + (0x0bddded4LL * zoe2) +
 919             (0x0160b5d0LL * zoe3), 30);
 920         zoc3 = Z_RSHIFT((-0x0de10cc4LL * zoo1) + (0x019b2a7dLL * zoo2) +
 921             (0x01cfe914LL * zoo3), 30);
 922         zoc4 = Z_RSHIFT((0x02aa12d7LL * zoe1) + (-0x03ff1bb3LL * zoe2) +
 923             (0x015508ddLL * zoe3), 30);
 924         zoc5 = Z_RSHIFT((0x051d29e5LL * zoo1) + (-0x028e7647LL * zoo2) +
 925             (0x0082d81aLL * zoo3), 30);
 926
 927         coeff = Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT(
 928             (int64_t)zoc5 * zoz, Z_SHIFT) +
 929             zoc4) * zoz, Z_SHIFT) + zoc3) * zoz, Z_SHIFT) +
 930             zoc2) * zoz, Z_SHIFT) + zoc1) * zoz, Z_SHIFT) + zoc0;
 931 #elif defined(Z_COEFF_INTERP_OPT8X)
 932         int32_t zoz, zoe1, zoe2, zoe3, zoo1, zoo2, zoo3;
 933         int32_t zoc0, zoc1, zoc2, zoc3, zoc4, zoc5;
 934
 935         /* 6-point, 5th-order Optimal 8x */
 936         zoz = z - (Z_ONE >> 1);
 937         zoe1 = z_coeff[1] + z_coeff[0];
 938         zoe2 = z_coeff[2] + z_coeff[-1];
 939         zoe3 = z_coeff[3] + z_coeff[-2];
 940         zoo1 = z_coeff[1] - z_coeff[0];
 941         zoo2 = z_coeff[2] - z_coeff[-1];
 942         zoo3 = z_coeff[3] - z_coeff[-2];
 943
 944         zoc0 = Z_RSHIFT((0x1aa9b47dLL * zoe1) + (0x053d9944LL * zoe2) +
 945             (0x0018b23fLL * zoe3), 30);
 946         zoc1 = Z_RSHIFT((0x14a104d1LL * zoo1) + (0x0d7d2504LL * zoo2) +
 947             (0x0094b599LL * zoo3), 30);
 948         zoc2 = Z_RSHIFT((-0x0d22530bLL * zoe1) + (0x0bb37a2cLL * zoe2) +
 949             (0x016ed8e0LL * zoe3), 30);
 950         zoc3 = Z_RSHIFT((-0x0d744b1cLL * zoo1) + (0x01649591LL * zoo2) +
 951             (0x01dae93aLL * zoo3), 30);
 952         zoc4 = Z_RSHIFT((0x02a7ee1bLL * zoe1) + (-0x03fbdb24LL * zoe2) +
 953             (0x0153ed07LL * zoe3), 30);
 954         zoc5 = Z_RSHIFT((0x04cf9b6cLL * zoo1) + (-0x0266b378LL * zoo2) +
 955             (0x007a7c26LL * zoo3), 30);
 956
 957         coeff = Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT(
 958             (int64_t)zoc5 * zoz, Z_SHIFT) +
 959             zoc4) * zoz, Z_SHIFT) + zoc3) * zoz, Z_SHIFT) +
 960             zoc2) * zoz, Z_SHIFT) + zoc1) * zoz, Z_SHIFT) + zoc0;
 961 #elif defined(Z_COEFF_INTERP_OPT4X)
 962         int32_t zoz, zoe1, zoe2, zoe3, zoo1, zoo2, zoo3;
 963         int32_t zoc0, zoc1, zoc2, zoc3, zoc4, zoc5;
 964
 965         /* 6-point, 5th-order Optimal 4x */
 966         zoz = z - (Z_ONE >> 1);
 967         zoe1 = z_coeff[1] + z_coeff[0];
 968         zoe2 = z_coeff[2] + z_coeff[-1];
 969         zoe3 = z_coeff[3] + z_coeff[-2];
 970         zoo1 = z_coeff[1] - z_coeff[0];
 971         zoo2 = z_coeff[2] - z_coeff[-1];
 972         zoo3 = z_coeff[3] - z_coeff[-2];
 973
 974         zoc0 = Z_RSHIFT((0x1a8eda43LL * zoe1) + (0x0556ee38LL * zoe2) +
 975             (0x001a3784LL * zoe3), 30);
 976         zoc1 = Z_RSHIFT((0x143d863eLL * zoo1) + (0x0d910e36LL * zoo2) +
 977             (0x009ca889LL * zoo3), 30);
 978         zoc2 = Z_RSHIFT((-0x0d026821LL * zoe1) + (0x0b837773LL * zoe2) +
 979             (0x017ef0c6LL * zoe3), 30);
 980         zoc3 = Z_RSHIFT((-0x0cef1502LL * zoo1) + (0x01207a8eLL * zoo2) +
 981             (0x01e936dbLL * zoo3), 30);
 982         zoc4 = Z_RSHIFT((0x029fe643LL * zoe1) + (-0x03ef3fc8LL * zoe2) +
 983             (0x014f5923LL * zoe3), 30);
 984         zoc5 = Z_RSHIFT((0x043a9d08LL * zoo1) + (-0x02154febLL * zoo2) +
 985             (0x00670dbdLL * zoo3), 30);
 986
 987         coeff = Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT(
 988             (int64_t)zoc5 * zoz, Z_SHIFT) +
 989             zoc4) * zoz, Z_SHIFT) + zoc3) * zoz, Z_SHIFT) +
 990             zoc2) * zoz, Z_SHIFT) + zoc1) * zoz, Z_SHIFT) + zoc0;
 991 #elif defined(Z_COEFF_INTERP_OPT2X)
 992         int32_t zoz, zoe1, zoe2, zoe3, zoo1, zoo2, zoo3;
 993         int32_t zoc0, zoc1, zoc2, zoc3, zoc4, zoc5;
 994
 995         /* 6-point, 5th-order Optimal 2x */
 996         zoz = z - (Z_ONE >> 1);
 997         zoe1 = z_coeff[1] + z_coeff[0];
 998         zoe2 = z_coeff[2] + z_coeff[-1];
 999         zoe3 = z_coeff[3] + z_coeff[-2];
1000         zoo1 = z_coeff[1] - z_coeff[0];
1001         zoo2 = z_coeff[2] - z_coeff[-1];
1002         zoo3 = z_coeff[3] - z_coeff[-2];
1003
1004         zoc0 = Z_RSHIFT((0x19edb6fdLL * zoe1) + (0x05ebd062LL * zoe2) +
1005             (0x00267881LL * zoe3), 30);
1006         zoc1 = Z_RSHIFT((0x1223af76LL * zoo1) + (0x0de3dd6bLL * zoo2) +
1007             (0x00d683cdLL * zoo3), 30);
1008         zoc2 = Z_RSHIFT((-0x0c3ee068LL * zoe1) + (0x0a5c3769LL * zoe2) +
1009             (0x01e2aceaLL * zoe3), 30);
1010         zoc3 = Z_RSHIFT((-0x0a8ab614LL * zoo1) + (-0x0019522eLL * zoo2) +
1011             (0x022cefc7LL * zoo3), 30);
1012         zoc4 = Z_RSHIFT((0x0276187dLL * zoe1) + (-0x03a801e8LL * zoe2) +
1013             (0x0131d935LL * zoe3), 30);
1014         zoc5 = Z_RSHIFT((0x02c373f5LL * zoo1) + (-0x01275f83LL * zoo2) +
1015             (0x0018ee79LL * zoo3), 30);
1016
1017         coeff = Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT(
1018             (int64_t)zoc5 * zoz, Z_SHIFT) +
1019             zoc4) * zoz, Z_SHIFT) + zoc3) * zoz, Z_SHIFT) +
1020             zoc2) * zoz, Z_SHIFT) + zoc1) * zoz, Z_SHIFT) + zoc0;
1021 #else
1022 #error "Interpolation type screwed!"
1023 #endif
1024
1025 #if Z_POLYPHASE_COEFF_SHIFT > 0
1026         coeff = Z_RSHIFT(coeff, Z_POLYPHASE_COEFF_SHIFT);
1027 #endif
1028         return (coeff);
1029 }
1030
1031 static int
1032 z_resampler_build_polyphase(struct z_info *info)
1033 {
1034         int32_t alpha, c, i, z, idx;
1035
1036         /* Let this be here first. */
1037         if (info->z_pcoeff != NULL) {
1038                 free(info->z_pcoeff, M_DEVBUF);
1039                 info->z_pcoeff = NULL;
1040         }
1041
1042         if (feeder_rate_polyphase_max < 1)
1043                 return (ENOTSUP);
1044
1045         if (((int64_t)info->z_size * info->z_gy * 2) >
1046             feeder_rate_polyphase_max) {
1047 #ifndef _KERNEL
1048                 fprintf(stderr, "Polyphase entries exceed: [%d/%d] %jd > %d\n",
1049                     info->z_gx, info->z_gy,
1050                     (intmax_t)info->z_size * info->z_gy * 2,
1051                     feeder_rate_polyphase_max);
1052 #endif
1053                 return (E2BIG);
1054         }
1055
1056         info->z_pcoeff = malloc(sizeof(int32_t) *
1057             info->z_size * info->z_gy * 2, M_DEVBUF, M_NOWAIT | M_ZERO);
1058         if (info->z_pcoeff == NULL)
1059                 return (ENOMEM);
1060
1061         for (alpha = 0; alpha < info->z_gy; alpha++) {
1062                 z = alpha * info->z_dx;
1063                 c = 0;
1064                 for (i = info->z_size; i != 0; i--) {
1065                         c += z >> Z_SHIFT;
1066                         z &= Z_MASK;
1067                         idx = (alpha * info->z_size * 2) +
1068                             (info->z_size * 2) - i;
1069                         info->z_pcoeff[idx] =
1070                             z_coeff_interpolate(z, info->z_coeff + c);
1071                         z += info->z_dy;
1072                 }
1073                 z = info->z_dy - (alpha * info->z_dx);
1074                 c = 0;
1075                 for (i = info->z_size; i != 0; i--) {
1076                         c += z >> Z_SHIFT;
1077                         z &= Z_MASK;
1078                         idx = (alpha * info->z_size * 2) + i - 1;
1079                         info->z_pcoeff[idx] =
1080                             z_coeff_interpolate(z, info->z_coeff + c);
1081                         z += info->z_dy;
1082                 }
1083         }
1084
1085 #ifndef _KERNEL
1086         fprintf(stderr, "Polyphase: [%d/%d] %d entries\n",
1087             info->z_gx, info->z_gy, info->z_size * info->z_gy * 2);
1088 #endif
1089
1090         return (0);
1091 }
1092
1093 static int
1094 z_resampler_setup(struct pcm_feeder *f)
1095 {
1096         struct z_info *info;
1097         int64_t gy2gx_max, gx2gy_max;
1098         uint32_t format;
1099         int32_t align, i, z_scale;
1100         int adaptive;
1101
1102         info = f->data;
1103         z_resampler_reset(info);
1104
1105         if (info->src == info->dst)
1106                 return (0);
1107
1108         /* Shrink by greatest common divisor. */
1109         i = z_gcd(info->src, info->dst);
1110         info->z_gx = info->src / i;
1111         info->z_gy = info->dst / i;
1112
1113         /* Too big, or too small. Bail out. */
1114         if (!(Z_FACTOR_SAFE(info->z_gx) && Z_FACTOR_SAFE(info->z_gy)))
1115                 return (EINVAL);
1116
1117         format = f->desc->in;
1118         adaptive = 0;
1119         z_scale = 0;
1120
1121         /*
1122          * Setup everything: filter length, conversion factor, etc.
1123          */
1124         if (Z_IS_SINC(info)) {
1125                 /*
1126                  * Downsampling, or upsampling scaling factor. As long as the
1127                  * factor can be represented by a fraction of 1 << Z_SHIFT,
1128                  * we're pretty much in business. Scaling is not needed for
1129                  * upsampling, so we just slap Z_ONE there.
1130                  */
1131                 if (info->z_gx > info->z_gy)
1132                         /*
1133                          * If the downsampling ratio is beyond sanity,
1134                          * enable semi-adaptive mode. Although handling
1135                          * extreme ratio is possible, the result of the
1136                          * conversion is just pointless, unworthy,
1137                          * nonsensical noises, etc.
1138                          */
1139                         if ((info->z_gx / info->z_gy) > Z_SINC_DOWNMAX)
1140                                 z_scale = Z_ONE / Z_SINC_DOWNMAX;
1141                         else
1142                                 z_scale = ((uint64_t)info->z_gy << Z_SHIFT) /
1143                                     info->z_gx;
1144                 else
1145                         z_scale = Z_ONE;
1146
1147                 /*
1148                  * This is actually impossible, unless anything above
1149                  * overflow.
1150                  */
1151                 if (z_scale < 1)
1152                         return (E2BIG);
1153
1154                 /*
1155                  * Calculate sample time/coefficients index drift. It is
1156                  * a constant for upsampling, but downsampling require
1157                  * heavy duty filtering with possible too long filters.
1158                  * If anything goes wrong, revisit again and enable
1159                  * adaptive mode.
1160                  */
1161 z_setup_adaptive_sinc:
1162                 if (info->z_pcoeff != NULL) {
1163                         free(info->z_pcoeff, M_DEVBUF);
1164                         info->z_pcoeff = NULL;
1165                 }
1166
1167                 if (adaptive == 0) {
1168                         info->z_dy = z_scale << Z_DRIFT_SHIFT;
1169                         if (info->z_dy < 1)
1170                                 return (E2BIG);
1171                         info->z_scale = z_scale;
1172                 } else {
1173                         info->z_dy = Z_FULL_ONE;
1174                         info->z_scale = Z_ONE;
1175                 }
1176
1177 #if 0
1178 #define Z_SCALE_DIV     10000
1179 #define Z_SCALE_LIMIT(s, v)                                             \
1180         ((((uint64_t)(s) * (v)) + (Z_SCALE_DIV >> 1)) / Z_SCALE_DIV)
1181
1182                 info->z_scale = Z_SCALE_LIMIT(info->z_scale, 9780);
1183 #endif
1184
1185                 /* Smallest drift increment. */
1186                 info->z_dx = info->z_dy / info->z_gy;
1187
1188                 /*
1189                  * Overflow or underflow. Try adaptive, let it continue and
1190                  * retry.
1191                  */
1192                 if (info->z_dx < 1) {
1193                         if (adaptive == 0) {
1194                                 adaptive = 1;
1195                                 goto z_setup_adaptive_sinc;
1196                         }
1197                         return (E2BIG);
1198                 }
1199
1200                 /*
1201                  * Round back output drift.
1202                  */
1203                 info->z_dy = info->z_dx * info->z_gy;
1204
1205                 for (i = 0; i < Z_COEFF_TAB_SIZE; i++) {
1206                         if (Z_SINC_COEFF_IDX(info) != i)
1207                                 continue;
1208                         /*
1209                          * Calculate required filter length and guard
1210                          * against possible abusive result. Note that
1211                          * this represents only 1/2 of the entire filter
1212                          * length.
1213                          */
1214                         info->z_size = z_resampler_sinc_len(info);
1215
1216                         /*
1217                          * Multiple of 2 rounding, for better accumulator
1218                          * performance.
1219                          */
1220                         info->z_size &= ~1;
1221
1222                         if (info->z_size < 2 || info->z_size > Z_SINC_MAX) {
1223                                 if (adaptive == 0) {
1224                                         adaptive = 1;
1225                                         goto z_setup_adaptive_sinc;
1226                                 }
1227                                 return (E2BIG);
1228                         }
1229                         info->z_coeff = z_coeff_tab[i].coeff + Z_COEFF_OFFSET;
1230                         info->z_dcoeff = z_coeff_tab[i].dcoeff;
1231                         break;
1232                 }
1233
1234                 if (info->z_coeff == NULL || info->z_dcoeff == NULL)
1235                         return (EINVAL);
1236         } else if (Z_IS_LINEAR(info)) {
1237                 /*
1238                  * Don't put much effort if we're doing linear interpolation.
1239                  * Just center the interpolation distance within Z_LINEAR_ONE,
1240                  * and be happy about it.
1241                  */
1242                 info->z_dx = Z_LINEAR_FULL_ONE / info->z_gy;
1243         }
1244
1245         /*
1246          * We're safe for now, lets continue.. Look for our resampler
1247          * depending on configured format and quality.
1248          */
1249         for (i = 0; i < Z_RESAMPLER_TAB_SIZE; i++) {
1250                 int ridx;
1251
1252                 if (AFMT_ENCODING(format) != z_resampler_tab[i].format)
1253                         continue;
1254                 if (Z_IS_SINC(info) && adaptive == 0 &&
1255                     z_resampler_build_polyphase(info) == 0)
1256                         ridx = Z_RESAMPLER_SINC_POLYPHASE;
1257                 else
1258                         ridx = Z_RESAMPLER_IDX(info);
1259                 info->z_resample = z_resampler_tab[i].resampler[ridx];
1260                 break;
1261         }
1262
1263         if (info->z_resample == NULL)
1264                 return (EINVAL);
1265
1266         info->bps = AFMT_BPS(format);
1267         align = info->channels * info->bps;
1268
1269         /*
1270          * Calculate largest value that can be fed into z_gy2gx() and
1271          * z_gx2gy() without causing (signed) 32bit overflow. z_gy2gx() will
1272          * be called early during feeding process to determine how much input
1273          * samples that is required to generate requested output, while
1274          * z_gx2gy() will be called just before samples filtering /
1275          * accumulation process based on available samples that has been
1276          * calculated using z_gx2gy().
1277          *
1278          * Now that is damn confusing, I guess ;-) .
1279          */
1280         gy2gx_max = (((uint64_t)info->z_gy * INT32_MAX) - info->z_gy + 1) /
1281             info->z_gx;
1282
1283         if ((gy2gx_max * align) > SND_FXDIV_MAX)
1284                 gy2gx_max = SND_FXDIV_MAX / align;
1285
1286         if (gy2gx_max < 1)
1287                 return (E2BIG);
1288
1289         gx2gy_max = (((uint64_t)info->z_gx * INT32_MAX) - info->z_gy) /
1290             info->z_gy;
1291
1292         if (gx2gy_max > INT32_MAX)
1293                 gx2gy_max = INT32_MAX;
1294
1295         if (gx2gy_max < 1)
1296                 return (E2BIG);
1297
1298         /*
1299          * Ensure that z_gy2gx() at its largest possible calculated value
1300          * (alpha = 0) will not cause overflow further late during z_gx2gy()
1301          * stage.
1302          */
1303         if (z_gy2gx(info, gy2gx_max) > _Z_GCAST(gx2gy_max))
1304                 return (E2BIG);
1305
1306         info->z_maxfeed = gy2gx_max * align;
1307
1308 #ifdef Z_USE_ALPHADRIFT
1309         info->z_startdrift = z_gy2gx(info, 1);
1310         info->z_alphadrift = z_drift(info, info->z_startdrift, 1);
1311 #endif
1312
1313         i = z_gy2gx(info, 1);
1314         info->z_full = z_roundpow2((info->z_size << 1) + i);
1315
1316         /*
1317          * Too big to be true, and overflowing left and right like mad ..
1318          */
1319         if ((info->z_full * align) < 1) {
1320                 if (adaptive == 0 && Z_IS_SINC(info)) {
1321                         adaptive = 1;
1322                         goto z_setup_adaptive_sinc;
1323                 }
1324                 return (E2BIG);
1325         }
1326
1327         /*
1328          * Increase full buffer size if its too small to reduce cyclic
1329          * buffer shifting in main conversion/feeder loop.
1330          */
1331         while (info->z_full < Z_RESERVOIR_MAX &&
1332             (info->z_full - (info->z_size << 1)) < Z_RESERVOIR)
1333                 info->z_full <<= 1;
1334
1335         /* Initialize buffer position. */
1336         info->z_mask = info->z_full - 1;
1337         info->z_start = z_prev(info, info->z_size << 1, 1);
1338         info->z_pos = z_next(info, info->z_start, 1);
1339
1340         /*
1341          * Allocate or reuse delay line buffer, whichever makes sense.
1342          */
1343         i = info->z_full * align;
1344         if (i < 1)
1345                 return (E2BIG);
1346
1347         if (info->z_delay == NULL || info->z_alloc < i ||
1348             i <= (info->z_alloc >> 1)) {
1349                 if (info->z_delay != NULL)
1350                         free(info->z_delay, M_DEVBUF);
1351                 info->z_delay = malloc(i, M_DEVBUF, M_NOWAIT | M_ZERO);
1352                 if (info->z_delay == NULL)
1353                         return (ENOMEM);
1354                 info->z_alloc = i;
1355         }
1356
1357         /*
1358          * Zero out head of buffer to avoid pops and clicks.
1359          */
1360         memset(info->z_delay, sndbuf_zerodata(f->desc->out),
1361             info->z_pos * align);
1362
1363 #ifdef Z_DIAGNOSTIC
1364         /*
1365          * XXX Debuging mess !@#$%^
1366          */
1367 #define dumpz(x)        fprintf(stderr, "\t%12s = %10u : %-11d\n",      \
1368                             "z_"__STRING(x), (uint32_t)info->z_##x,     \
1369                             (int32_t)info->z_##x)
1370         fprintf(stderr, "\n%s():\n", __func__);
1371         fprintf(stderr, "\tchannels=%d, bps=%d, format=0x%08x, quality=%d\n",
1372             info->channels, info->bps, format, info->quality);
1373         fprintf(stderr, "\t%d (%d) -> %d (%d), ",
1374             info->src, info->rsrc, info->dst, info->rdst);
1375         fprintf(stderr, "[%d/%d]\n", info->z_gx, info->z_gy);
1376         fprintf(stderr, "\tminreq=%d, ", z_gy2gx(info, 1));
1377         if (adaptive != 0)
1378                 z_scale = Z_ONE;
1379         fprintf(stderr, "factor=0x%08x/0x%08x (%f)\n",
1380             z_scale, Z_ONE, (double)z_scale / Z_ONE);
1381         fprintf(stderr, "\tbase_length=%d, ", Z_SINC_BASE_LEN(info));
1382         fprintf(stderr, "adaptive=%s\n", (adaptive != 0) ? "YES" : "NO");
1383         dumpz(size);
1384         dumpz(alloc);
1385         if (info->z_alloc < 1024)
1386                 fprintf(stderr, "\t%15s%10d Bytes\n",
1387                     "", info->z_alloc);
1388         else if (info->z_alloc < (1024 << 10))
1389                 fprintf(stderr, "\t%15s%10d KBytes\n",
1390                     "", info->z_alloc >> 10);
1391         else if (info->z_alloc < (1024 << 20))
1392                 fprintf(stderr, "\t%15s%10d MBytes\n",
1393                     "", info->z_alloc >> 20);
1394         else
1395                 fprintf(stderr, "\t%15s%10d GBytes\n",
1396                     "", info->z_alloc >> 30);
1397         fprintf(stderr, "\t%12s   %10d (min output samples)\n",
1398             "",
1399             (int32_t)z_gx2gy(info, info->z_full - (info->z_size << 1)));
1400         fprintf(stderr, "\t%12s   %10d (min allocated output samples)\n",
1401             "",
1402             (int32_t)z_gx2gy(info, (info->z_alloc / align) -
1403             (info->z_size << 1)));
1404         fprintf(stderr, "\t%12s = %10d\n",
1405             "z_gy2gx()", (int32_t)z_gy2gx(info, 1));
1406         fprintf(stderr, "\t%12s = %10d -> z_gy2gx() -> %d\n",
1407             "Max", (int32_t)gy2gx_max, (int32_t)z_gy2gx(info, gy2gx_max));
1408         fprintf(stderr, "\t%12s = %10d\n",
1409             "z_gx2gy()", (int32_t)z_gx2gy(info, 1));
1410         fprintf(stderr, "\t%12s = %10d -> z_gx2gy() -> %d\n",
1411             "Max", (int32_t)gx2gy_max, (int32_t)z_gx2gy(info, gx2gy_max));
1412         dumpz(maxfeed);
1413         dumpz(full);
1414         dumpz(start);
1415         dumpz(pos);
1416         dumpz(scale);
1417         fprintf(stderr, "\t%12s   %10f\n", "",
1418             (double)info->z_scale / Z_ONE);
1419         dumpz(dx);
1420         fprintf(stderr, "\t%12s   %10f\n", "",
1421             (double)info->z_dx / info->z_dy);
1422         dumpz(dy);
1423         fprintf(stderr, "\t%12s   %10d (drift step)\n", "",
1424             info->z_dy >> Z_SHIFT);
1425         fprintf(stderr, "\t%12s   %10d (scaling differences)\n", "",
1426             (z_scale << Z_DRIFT_SHIFT) - info->z_dy);
1427         fprintf(stderr, "\t%12s = %u bytes\n",
1428             "intpcm32_t", sizeof(intpcm32_t));
1429         fprintf(stderr, "\t%12s = 0x%08x, smallest=%.16lf\n",
1430             "Z_ONE", Z_ONE, (double)1.0 / (double)Z_ONE);
1431 #endif
1432
1433         return (0);
1434 }
1435
1436 static int
1437 z_resampler_set(struct pcm_feeder *f, int what, int32_t value)
1438 {
1439         struct z_info *info;
1440         int32_t oquality;
1441
1442         info = f->data;
1443
1444         switch (what) {
1445         case Z_RATE_SRC:
1446                 if (value < feeder_rate_min || value > feeder_rate_max)
1447                         return (E2BIG);
1448                 if (value == info->rsrc)
1449                         return (0);
1450                 info->rsrc = value;
1451                 break;
1452         case Z_RATE_DST:
1453                 if (value < feeder_rate_min || value > feeder_rate_max)
1454                         return (E2BIG);
1455                 if (value == info->rdst)
1456                         return (0);
1457                 info->rdst = value;
1458                 break;
1459         case Z_RATE_QUALITY:
1460                 if (value < Z_QUALITY_MIN || value > Z_QUALITY_MAX)
1461                         return (EINVAL);
1462                 if (value == info->quality)
1463                         return (0);
1464                 /*
1465                  * If we failed to set the requested quality, restore
1466                  * the old one. We cannot afford leaving it broken since
1467                  * passive feeder chains like vchans never reinitialize
1468                  * itself.
1469                  */
1470                 oquality = info->quality;
1471                 info->quality = value;
1472                 if (z_resampler_setup(f) == 0)
1473                         return (0);
1474                 info->quality = oquality;
1475                 break;
1476         case Z_RATE_CHANNELS:
1477                 if (value < SND_CHN_MIN || value > SND_CHN_MAX)
1478                         return (EINVAL);
1479                 if (value == info->channels)
1480                         return (0);
1481                 info->channels = value;
1482                 break;
1483         default:
1484                 return (EINVAL);
1485                 break;
1486         }
1487
1488         return (z_resampler_setup(f));
1489 }
1490
1491 static int
1492 z_resampler_get(struct pcm_feeder *f, int what)
1493 {
1494         struct z_info *info;
1495
1496         info = f->data;
1497
1498         switch (what) {
1499         case Z_RATE_SRC:
1500                 return (info->rsrc);
1501                 break;
1502         case Z_RATE_DST:
1503                 return (info->rdst);
1504                 break;
1505         case Z_RATE_QUALITY:
1506                 return (info->quality);
1507                 break;
1508         case Z_RATE_CHANNELS:
1509                 return (info->channels);
1510                 break;
1511         default:
1512                 break;
1513         }
1514
1515         return (-1);
1516 }
1517
1518 static int
1519 z_resampler_init(struct pcm_feeder *f)
1520 {
1521         struct z_info *info;
1522         int ret;
1523
1524         if (f->desc->in != f->desc->out)
1525                 return (EINVAL);
1526
1527         info = malloc(sizeof(*info), M_DEVBUF, M_NOWAIT | M_ZERO);
1528         if (info == NULL)
1529                 return (ENOMEM);
1530
1531         info->rsrc = Z_RATE_DEFAULT;
1532         info->rdst = Z_RATE_DEFAULT;
1533         info->quality = feeder_rate_quality;
1534         info->channels = AFMT_CHANNEL(f->desc->in);
1535
1536         f->data = info;
1537
1538         ret = z_resampler_setup(f);
1539         if (ret != 0) {
1540                 if (info->z_pcoeff != NULL)
1541                         free(info->z_pcoeff, M_DEVBUF);
1542                 if (info->z_delay != NULL)
1543                         free(info->z_delay, M_DEVBUF);
1544                 free(info, M_DEVBUF);
1545                 f->data = NULL;
1546         }
1547
1548         return (ret);
1549 }
1550
1551 static int
1552 z_resampler_free(struct pcm_feeder *f)
1553 {
1554         struct z_info *info;
1555
1556         info = f->data;
1557         if (info != NULL) {
1558                 if (info->z_pcoeff != NULL)
1559                         free(info->z_pcoeff, M_DEVBUF);
1560                 if (info->z_delay != NULL)
1561                         free(info->z_delay, M_DEVBUF);
1562                 free(info, M_DEVBUF);
1563         }
1564
1565         f->data = NULL;
1566
1567         return (0);
1568 }
1569
1570 static uint32_t
1571 z_resampler_feed_internal(struct pcm_feeder *f, struct pcm_channel *c,
1572     uint8_t *b, uint32_t count, void *source)
1573 {
1574         struct z_info *info;
1575         int32_t alphadrift, startdrift, reqout, ocount, reqin, align;
1576         int32_t fetch, fetched, start, cp;
1577         uint8_t *dst;
1578
1579         info = f->data;
1580         if (info->z_resample == NULL)
1581                 return (z_feed(f->source, c, b, count, source));
1582
1583         /*
1584          * Calculate sample size alignment and amount of sample output.
1585          * We will do everything in sample domain, but at the end we
1586          * will jump back to byte domain.
1587          */
1588         align = info->channels * info->bps;
1589         ocount = SND_FXDIV(count, align);
1590         if (ocount == 0)
1591                 return (0);
1592
1593         /*
1594          * Calculate amount of input samples that is needed to generate
1595          * exact amount of output.
1596          */
1597         reqin = z_gy2gx(info, ocount) - z_fetched(info);
1598
1599 #ifdef Z_USE_ALPHADRIFT
1600         startdrift = info->z_startdrift;
1601         alphadrift = info->z_alphadrift;
1602 #else
1603         startdrift = _Z_GY2GX(info, 0, 1);
1604         alphadrift = z_drift(info, startdrift, 1);
1605 #endif
1606
1607         dst = b;
1608
1609         do {
1610                 if (reqin != 0) {
1611                         fetch = z_min(z_free(info), reqin);
1612                         if (fetch == 0) {
1613                                 /*
1614                                  * No more free spaces, so wind enough
1615                                  * samples back to the head of delay line
1616                                  * in byte domain.
1617                                  */
1618                                 fetched = z_fetched(info);
1619                                 start = z_prev(info, info->z_start,
1620                                     (info->z_size << 1) - 1);
1621                                 cp = (info->z_size << 1) + fetched;
1622                                 z_copy(info->z_delay + (start * align),
1623                                     info->z_delay, cp * align);
1624                                 info->z_start =
1625                                     z_prev(info, info->z_size << 1, 1);
1626                                 info->z_pos =
1627                                     z_next(info, info->z_start, fetched + 1);
1628                                 fetch = z_min(z_free(info), reqin);
1629 #ifdef Z_DIAGNOSTIC
1630                                 if (1) {
1631                                         static uint32_t kk = 0;
1632                                         fprintf(stderr,
1633                                             "Buffer Move: "
1634                                             "start=%d fetched=%d cp=%d "
1635                                             "cycle=%u [%u]\r",
1636                                             start, fetched, cp, info->z_cycle,
1637                                             ++kk);
1638                                 }
1639                                 info->z_cycle = 0;
1640 #endif
1641                         }
1642                         if (fetch != 0) {
1643                                 /*
1644                                  * Fetch in byte domain and jump back
1645                                  * to sample domain.
1646                                  */
1647                                 fetched = SND_FXDIV(z_feed(f->source, c,
1648                                     info->z_delay + (info->z_pos * align),
1649                                     fetch * align, source), align);
1650                                 /*
1651                                  * Prepare to convert fetched buffer,
1652                                  * or mark us done if we cannot fulfill
1653                                  * the request.
1654                                  */
1655                                 reqin -= fetched;
1656                                 info->z_pos += fetched;
1657                                 if (fetched != fetch)
1658                                         reqin = 0;
1659                         }
1660                 }
1661
1662                 reqout = z_min(z_gx2gy(info, z_fetched(info)), ocount);
1663                 if (reqout != 0) {
1664                         ocount -= reqout;
1665
1666                         /*
1667                          * Drift.. drift.. drift..
1668                          *
1669                          * Notice that there are 2 methods of doing the drift
1670                          * operations: The former is much cleaner (in a sense
1671                          * of mathematical readings of my eyes), but slower
1672                          * due to integer division in z_gy2gx(). Nevertheless,
1673                          * both should give the same exact accurate drifting
1674                          * results, so the later is favourable.
1675                          */
1676                         do {
1677                                 info->z_resample(info, dst);
1678 #if 0
1679                                 startdrift = z_gy2gx(info, 1);
1680                                 alphadrift = z_drift(info, startdrift, 1);
1681                                 info->z_start += startdrift;
1682                                 info->z_alpha += alphadrift;
1683 #else
1684                                 info->z_alpha += alphadrift;
1685                                 if (info->z_alpha < info->z_gy)
1686                                         info->z_start += startdrift;
1687                                 else {
1688                                         info->z_start += startdrift - 1;
1689                                         info->z_alpha -= info->z_gy;
1690                                 }
1691 #endif
1692                                 dst += align;
1693 #ifdef Z_DIAGNOSTIC
1694                                 info->z_cycle++;
1695 #endif
1696                         } while (--reqout != 0);
1697                 }
1698         } while (reqin != 0 && ocount != 0);
1699
1700         /*
1701          * Back to byte domain..
1702          */
1703         return (dst - b);
1704 }
1705
1706 static int
1707 z_resampler_feed(struct pcm_feeder *f, struct pcm_channel *c, uint8_t *b,
1708     uint32_t count, void *source)
1709 {
1710         uint32_t feed, maxfeed, left;
1711
1712         /*
1713          * Split count to smaller chunks to avoid possible 32bit overflow.
1714          */
1715         maxfeed = ((struct z_info *)(f->data))->z_maxfeed;
1716         left = count;
1717
1718         do {
1719                 feed = z_resampler_feed_internal(f, c, b,
1720                     z_min(maxfeed, left), source);
1721                 b += feed;
1722                 left -= feed;
1723         } while (left != 0 && feed != 0);
1724
1725         return (count - left);
1726 }
1727
1728 static struct pcm_feederdesc feeder_rate_desc[] = {
1729         { FEEDER_RATE, 0, 0, 0, 0 },
1730         { 0, 0, 0, 0, 0 },
1731 };
1732
1733 static kobj_method_t feeder_rate_methods[] = {
1734         KOBJMETHOD(feeder_init,         z_resampler_init),
1735         KOBJMETHOD(feeder_free,         z_resampler_free),
1736         KOBJMETHOD(feeder_set,          z_resampler_set),
1737         KOBJMETHOD(feeder_get,          z_resampler_get),
1738         KOBJMETHOD(feeder_feed,         z_resampler_feed),
1739         KOBJMETHOD_END
1740 };
1741
1742 FEEDER_DECLARE(feeder_rate, NULL);