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("$FreeBSD$");
  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 TUNABLE_INT("hw.snd.feeder_rate_polyphase_max", &feeder_rate_polyphase_max);
 172 SYSCTL_INT(_hw_snd, OID_AUTO, feeder_rate_polyphase_max, CTLFLAG_RW,
 173     &feeder_rate_polyphase_max, 0, "maximum allowable polyphase entries");
 174
 175 static int
 176 sysctl_hw_snd_feeder_rate_min(SYSCTL_HANDLER_ARGS)
 177 {
 178         int err, val;
 179
 180         val = feeder_rate_min;
 181         err = sysctl_handle_int(oidp, &val, 0, req);
 182
 183         if (err != 0 || req->newptr == NULL || val == feeder_rate_min)
 184                 return (err);
 185
 186         if (!(Z_FACTOR_SAFE(val) && val < feeder_rate_max))
 187                 return (EINVAL);
 188
 189         feeder_rate_min = val;
 190
 191         return (0);
 192 }
 193 SYSCTL_PROC(_hw_snd, OID_AUTO, feeder_rate_min, CTLTYPE_INT | CTLFLAG_RW,
 194     0, sizeof(int), sysctl_hw_snd_feeder_rate_min, "I",
 195     "minimum allowable rate");
 196
 197 static int
 198 sysctl_hw_snd_feeder_rate_max(SYSCTL_HANDLER_ARGS)
 199 {
 200         int err, val;
 201
 202         val = feeder_rate_max;
 203         err = sysctl_handle_int(oidp, &val, 0, req);
 204
 205         if (err != 0 || req->newptr == NULL || val == feeder_rate_max)
 206                 return (err);
 207
 208         if (!(Z_FACTOR_SAFE(val) && val > feeder_rate_min))
 209                 return (EINVAL);
 210
 211         feeder_rate_max = val;
 212
 213         return (0);
 214 }
 215 SYSCTL_PROC(_hw_snd, OID_AUTO, feeder_rate_max, CTLTYPE_INT | CTLFLAG_RW,
 216     0, sizeof(int), sysctl_hw_snd_feeder_rate_max, "I",
 217     "maximum allowable rate");
 218
 219 static int
 220 sysctl_hw_snd_feeder_rate_round(SYSCTL_HANDLER_ARGS)
 221 {
 222         int err, val;
 223
 224         val = feeder_rate_round;
 225         err = sysctl_handle_int(oidp, &val, 0, req);
 226
 227         if (err != 0 || req->newptr == NULL || val == feeder_rate_round)
 228                 return (err);
 229
 230         if (val < Z_ROUNDHZ_MIN || val > Z_ROUNDHZ_MAX)
 231                 return (EINVAL);
 232
 233         feeder_rate_round = val - (val % Z_ROUNDHZ);
 234
 235         return (0);
 236 }
 237 SYSCTL_PROC(_hw_snd, OID_AUTO, feeder_rate_round, CTLTYPE_INT | CTLFLAG_RW,
 238     0, sizeof(int), sysctl_hw_snd_feeder_rate_round, "I",
 239     "sample rate converter rounding threshold");
 240
 241 static int
 242 sysctl_hw_snd_feeder_rate_quality(SYSCTL_HANDLER_ARGS)
 243 {
 244         struct snddev_info *d;
 245         struct pcm_channel *c;
 246         struct pcm_feeder *f;
 247         int i, err, val;
 248
 249         val = feeder_rate_quality;
 250         err = sysctl_handle_int(oidp, &val, 0, req);
 251
 252         if (err != 0 || req->newptr == NULL || val == feeder_rate_quality)
 253                 return (err);
 254
 255         if (val < Z_QUALITY_MIN || val > Z_QUALITY_MAX)
 256                 return (EINVAL);
 257
 258         feeder_rate_quality = val;
 259
 260         /*
 261          * Traverse all available channels on each device and try to
 262          * set resampler quality if and only if it is exist as
 263          * part of feeder chains and the channel is idle.
 264          */
 265         for (i = 0; pcm_devclass != NULL &&
 266             i < devclass_get_maxunit(pcm_devclass); i++) {
 267                 d = devclass_get_softc(pcm_devclass, i);
 268                 if (!PCM_REGISTERED(d))
 269                         continue;
 270                 PCM_LOCK(d);
 271                 PCM_WAIT(d);
 272                 PCM_ACQUIRE(d);
 273                 CHN_FOREACH(c, d, channels.pcm) {
 274                         CHN_LOCK(c);
 275                         f = chn_findfeeder(c, FEEDER_RATE);
 276                         if (f == NULL || f->data == NULL || CHN_STARTED(c)) {
 277                                 CHN_UNLOCK(c);
 278                                 continue;
 279                         }
 280                         (void)FEEDER_SET(f, FEEDRATE_QUALITY, val);
 281                         CHN_UNLOCK(c);
 282                 }
 283                 PCM_RELEASE(d);
 284                 PCM_UNLOCK(d);
 285         }
 286
 287         return (0);
 288 }
 289 SYSCTL_PROC(_hw_snd, OID_AUTO, feeder_rate_quality, CTLTYPE_INT | CTLFLAG_RW,
 290     0, sizeof(int), sysctl_hw_snd_feeder_rate_quality, "I",
 291     "sample rate converter quality ("__XSTRING(Z_QUALITY_MIN)"=low .. "
 292     __XSTRING(Z_QUALITY_MAX)"=high)");
 293 #endif  /* _KERNEL */
 294
 295
 296 /*
 297  * Resampler type.
 298  */
 299 #define Z_IS_ZOH(i)             ((i)->quality == Z_QUALITY_ZOH)
 300 #define Z_IS_LINEAR(i)          ((i)->quality == Z_QUALITY_LINEAR)
 301 #define Z_IS_SINC(i)            ((i)->quality > Z_QUALITY_LINEAR)
 302
 303 /*
 304  * Macroses for accurate sample time drift calculations.
 305  *
 306  * gy2gx : given the amount of output, return the _exact_ required amount of
 307  *         input.
 308  * gx2gy : given the amount of input, return the _maximum_ amount of output
 309  *         that will be generated.
 310  * drift : given the amount of input and output, return the elapsed
 311  *         sample-time.
 312  */
 313 #define _Z_GCAST(x)             ((uint64_t)(x))
 314
 315 #if defined(__GNUCLIKE_ASM) && defined(__i386__)
 316 /*
 317  * This is where i386 being beaten to a pulp. Fortunately this function is
 318  * rarely being called and if it is, it will decide the best (hopefully)
 319  * fastest way to do the division. If we can ensure that everything is dword
 320  * aligned, letting the compiler to call udivdi3 to do the division can be
 321  * faster compared to this.
 322  *
 323  * amd64 is the clear winner here, no question about it.
 324  */
 325 static __inline uint32_t
 326 Z_DIV(uint64_t v, uint32_t d)
 327 {
 328         uint32_t hi, lo, quo, rem;
 329
 330         hi = v >> 32;
 331         lo = v & 0xffffffff;
 332
 333         /*
 334          * As much as we can, try to avoid long division like a plague.
 335          */
 336         if (hi == 0)
 337                 quo = lo / d;
 338         else
 339                 __asm("divl %2"
 340                     : "=a" (quo), "=d" (rem)
 341                     : "r" (d), "0" (lo), "1" (hi));
 342
 343         return (quo);
 344 }
 345 #else
 346 #define Z_DIV(x, y)             ((x) / (y))
 347 #endif
 348
 349 #define _Z_GY2GX(i, a, v)                                               \
 350         Z_DIV(((_Z_GCAST((i)->z_gx) * (v)) + ((i)->z_gy - (a) - 1)),    \
 351         (i)->z_gy)
 352
 353 #define _Z_GX2GY(i, a, v)                                               \
 354         Z_DIV(((_Z_GCAST((i)->z_gy) * (v)) + (a)), (i)->z_gx)
 355
 356 #define _Z_DRIFT(i, x, y)                                               \
 357         ((_Z_GCAST((i)->z_gy) * (x)) - (_Z_GCAST((i)->z_gx) * (y)))
 358
 359 #define z_gy2gx(i, v)           _Z_GY2GX(i, (i)->z_alpha, v)
 360 #define z_gx2gy(i, v)           _Z_GX2GY(i, (i)->z_alpha, v)
 361 #define z_drift(i, x, y)        _Z_DRIFT(i, x, y)
 362
 363 /*
 364  * Macroses for SINC coefficients table manipulations.. whatever.
 365  */
 366 #define Z_SINC_COEFF_IDX(i)     ((i)->quality - Z_QUALITY_LINEAR - 1)
 367
 368 #define Z_SINC_LEN(i)                                                   \
 369         ((int32_t)(((uint64_t)z_coeff_tab[Z_SINC_COEFF_IDX(i)].len <<   \
 370             Z_SHIFT) / (i)->z_dy))
 371
 372 #define Z_SINC_BASE_LEN(i)                                              \
 373         ((z_coeff_tab[Z_SINC_COEFF_IDX(i)].len - 1) >> (Z_DRIFT_SHIFT - 1))
 374
 375 /*
 376  * Macroses for linear delay buffer operations. Alignment is not
 377  * really necessary since we're not using true circular buffer, but it
 378  * will help us guard against possible trespasser. To be honest,
 379  * the linear block operations does not need guarding at all due to
 380  * accurate drifting!
 381  */
 382 #define z_align(i, v)           ((v) & (i)->z_mask)
 383 #define z_next(i, o, v)         z_align(i, (o) + (v))
 384 #define z_prev(i, o, v)         z_align(i, (o) - (v))
 385 #define z_fetched(i)            (z_align(i, (i)->z_pos - (i)->z_start) - 1)
 386 #define z_free(i)               ((i)->z_full - (i)->z_pos)
 387
 388 /*
 389  * Macroses for Bla Bla .. :)
 390  */
 391 #define z_copy(src, dst, sz)    (void)memcpy(dst, src, sz)
 392 #define z_feed(...)             FEEDER_FEED(__VA_ARGS__)
 393
 394 static __inline uint32_t
 395 z_min(uint32_t x, uint32_t y)
 396 {
 397
 398         return ((x < y) ? x : y);
 399 }
 400
 401 static int32_t
 402 z_gcd(int32_t x, int32_t y)
 403 {
 404         int32_t w;
 405
 406         while (y != 0) {
 407                 w = x % y;
 408                 x = y;
 409                 y = w;
 410         }
 411
 412         return (x);
 413 }
 414
 415 static int32_t
 416 z_roundpow2(int32_t v)
 417 {
 418         int32_t i;
 419
 420         i = 1;
 421
 422         /*
 423          * Let it overflow at will..
 424          */
 425         while (i > 0 && i < v)
 426                 i <<= 1;
 427
 428         return (i);
 429 }
 430
 431 /*
 432  * Zero Order Hold, the worst of the worst, an insult against quality,
 433  * but super fast.
 434  */
 435 static void
 436 z_feed_zoh(struct z_info *info, uint8_t *dst)
 437 {
 438 #if 0
 439         z_copy(info->z_delay +
 440             (info->z_start * info->channels * info->bps), dst,
 441             info->channels * info->bps);
 442 #else
 443         uint32_t cnt;
 444         uint8_t *src;
 445
 446         cnt = info->channels * info->bps;
 447         src = info->z_delay + (info->z_start * cnt);
 448
 449         /*
 450          * This is a bit faster than doing bcopy() since we're dealing
 451          * with possible unaligned samples.
 452          */
 453         do {
 454                 *dst++ = *src++;
 455         } while (--cnt != 0);
 456 #endif
 457 }
 458
 459 /*
 460  * Linear Interpolation. This at least sounds better (perceptually) and fast,
 461  * but without any proper filtering which means aliasing still exist and
 462  * could become worst with a right sample. Interpolation centered within
 463  * Z_LINEAR_ONE between the present and previous sample and everything is
 464  * done with simple 32bit scaling arithmetic.
 465  */
 466 #define Z_DECLARE_LINEAR(SIGN, BIT, ENDIAN)                                     \
 467 static void                                                                     \
 468 z_feed_linear_##SIGN##BIT##ENDIAN(struct z_info *info, uint8_t *dst)            \
 469 {                                                                               \
 470         int32_t z;                                                              \
 471         intpcm_t x, y;                                                          \
 472         uint32_t ch;                                                            \
 473         uint8_t *sx, *sy;                                                       \
 474                                                                                 \
 475         z = ((uint32_t)info->z_alpha * info->z_dx) >> Z_LINEAR_UNSHIFT;         \
 476                                                                                 \
 477         sx = info->z_delay + (info->z_start * info->channels *                  \
 478             PCM_##BIT##_BPS);                                                   \
 479         sy = sx - (info->channels * PCM_##BIT##_BPS);                           \
 480                                                                                 \
 481         ch = info->channels;                                                    \
 482                                                                                 \
 483         do {                                                                    \
 484                 x = _PCM_READ_##SIGN##BIT##_##ENDIAN(sx);                       \
 485                 y = _PCM_READ_##SIGN##BIT##_##ENDIAN(sy);                       \
 486                 x = Z_LINEAR_INTERPOLATE_##BIT(z, x, y);                        \
 487                 _PCM_WRITE_##SIGN##BIT##_##ENDIAN(dst, x);                      \
 488                 sx += PCM_##BIT##_BPS;                                          \
 489                 sy += PCM_##BIT##_BPS;                                          \
 490                 dst += PCM_##BIT##_BPS;                                         \
 491         } while (--ch != 0);                                                    \
 492 }
 493
 494 /*
 495  * Userland clipping diagnostic check, not enabled in kernel compilation.
 496  * While doing sinc interpolation, unrealistic samples like full scale sine
 497  * wav will clip, but for other things this will not make any noise at all.
 498  * Everybody should learn how to normalized perceived loudness of their own
 499  * music/sounds/samples (hint: ReplayGain).
 500  */
 501 #ifdef Z_DIAGNOSTIC
 502 #define Z_CLIP_CHECK(v, BIT)    do {                                    \
 503         if ((v) > PCM_S##BIT##_MAX) {                                   \
 504                 fprintf(stderr, "Overflow: v=%jd, max=%jd\n",           \
 505                     (intmax_t)(v), (intmax_t)PCM_S##BIT##_MAX);         \
 506         } else if ((v) < PCM_S##BIT##_MIN) {                            \
 507                 fprintf(stderr, "Underflow: v=%jd, min=%jd\n",          \
 508                     (intmax_t)(v), (intmax_t)PCM_S##BIT##_MIN);         \
 509         }                                                               \
 510 } while (0)
 511 #else
 512 #define Z_CLIP_CHECK(...)
 513 #endif
 514
 515 #define Z_CLAMP(v, BIT)                                                 \
 516         (((v) > PCM_S##BIT##_MAX) ? PCM_S##BIT##_MAX :                  \
 517         (((v) < PCM_S##BIT##_MIN) ? PCM_S##BIT##_MIN : (v)))
 518
 519 /*
 520  * Sine Cardinal (SINC) Interpolation. Scaling is done in 64 bit, so
 521  * there's no point to hold the plate any longer. All samples will be
 522  * shifted to a full 32 bit, scaled and restored during write for
 523  * maximum dynamic range (only for downsampling).
 524  */
 525 #define _Z_SINC_ACCUMULATE(SIGN, BIT, ENDIAN, adv)                      \
 526         c += z >> Z_SHIFT;                                              \
 527         z &= Z_MASK;                                                    \
 528         coeff = Z_COEFF_INTERPOLATE(z, z_coeff[c], z_dcoeff[c]);        \
 529         x = _PCM_READ_##SIGN##BIT##_##ENDIAN(p);                        \
 530         v += Z_NORM_##BIT((intpcm64_t)x * coeff);                       \
 531         z += info->z_dy;                                                \
 532         p adv##= info->channels * PCM_##BIT##_BPS
 533
 534 /*
 535  * XXX GCC4 optimization is such a !@#$%, need manual unrolling.
 536  */
 537 #if defined(__GNUC__) && __GNUC__ >= 4
 538 #define Z_SINC_ACCUMULATE(...)  do {                                    \
 539         _Z_SINC_ACCUMULATE(__VA_ARGS__);                                \
 540         _Z_SINC_ACCUMULATE(__VA_ARGS__);                                \
 541 } while (0)
 542 #define Z_SINC_ACCUMULATE_DECR          2
 543 #else
 544 #define Z_SINC_ACCUMULATE(...)  do {                                    \
 545         _Z_SINC_ACCUMULATE(__VA_ARGS__);                                \
 546 } while (0)
 547 #define Z_SINC_ACCUMULATE_DECR          1
 548 #endif
 549
 550 #define Z_DECLARE_SINC(SIGN, BIT, ENDIAN)                                       \
 551 static void                                                                     \
 552 z_feed_sinc_##SIGN##BIT##ENDIAN(struct z_info *info, uint8_t *dst)              \
 553 {                                                                               \
 554         intpcm64_t v;                                                           \
 555         intpcm_t x;                                                             \
 556         uint8_t *p;                                                             \
 557         int32_t coeff, z, *z_coeff, *z_dcoeff;                                  \
 558         uint32_t c, center, ch, i;                                              \
 559                                                                                 \
 560         z_coeff = info->z_coeff;                                                \
 561         z_dcoeff = info->z_dcoeff;                                              \
 562         center = z_prev(info, info->z_start, info->z_size);                     \
 563         ch = info->channels * PCM_##BIT##_BPS;                                  \
 564         dst += ch;                                                              \
 565                                                                                 \
 566         do {                                                                    \
 567                 dst -= PCM_##BIT##_BPS;                                         \
 568                 ch -= PCM_##BIT##_BPS;                                          \
 569                 v = 0;                                                          \
 570                 z = info->z_alpha * info->z_dx;                                 \
 571                 c = 0;                                                          \
 572                 p = info->z_delay + (z_next(info, center, 1) *                  \
 573                     info->channels * PCM_##BIT##_BPS) + ch;                     \
 574                 for (i = info->z_size; i != 0; i -= Z_SINC_ACCUMULATE_DECR)     \
 575                         Z_SINC_ACCUMULATE(SIGN, BIT, ENDIAN, +);                \
 576                 z = info->z_dy - (info->z_alpha * info->z_dx);                  \
 577                 c = 0;                                                          \
 578                 p = info->z_delay + (center * info->channels *                  \
 579                     PCM_##BIT##_BPS) + ch;                                      \
 580                 for (i = info->z_size; i != 0; i -= Z_SINC_ACCUMULATE_DECR)     \
 581                         Z_SINC_ACCUMULATE(SIGN, BIT, ENDIAN, -);                \
 582                 if (info->z_scale != Z_ONE)                                     \
 583                         v = Z_SCALE_##BIT(v, info->z_scale);                    \
 584                 else                                                            \
 585                         v >>= Z_COEFF_SHIFT - Z_GUARD_BIT_##BIT;                \
 586                 Z_CLIP_CHECK(v, BIT);                                           \
 587                 _PCM_WRITE_##SIGN##BIT##_##ENDIAN(dst, Z_CLAMP(v, BIT));        \
 588         } while (ch != 0);                                                      \
 589 }
 590
 591 #define Z_DECLARE_SINC_POLYPHASE(SIGN, BIT, ENDIAN)                             \
 592 static void                                                                     \
 593 z_feed_sinc_polyphase_##SIGN##BIT##ENDIAN(struct z_info *info, uint8_t *dst)    \
 594 {                                                                               \
 595         intpcm64_t v;                                                           \
 596         intpcm_t x;                                                             \
 597         uint8_t *p;                                                             \
 598         int32_t ch, i, start, *z_pcoeff;                                        \
 599                                                                                 \
 600         ch = info->channels * PCM_##BIT##_BPS;                                  \
 601         dst += ch;                                                              \
 602         start = z_prev(info, info->z_start, (info->z_size << 1) - 1) * ch;      \
 603                                                                                 \
 604         do {                                                                    \
 605                 dst -= PCM_##BIT##_BPS;                                         \
 606                 ch -= PCM_##BIT##_BPS;                                          \
 607                 v = 0;                                                          \
 608                 p = info->z_delay + start + ch;                                 \
 609                 z_pcoeff = info->z_pcoeff +                                     \
 610                     ((info->z_alpha * info->z_size) << 1);                      \
 611                 for (i = info->z_size; i != 0; i--) {                           \
 612                         x = _PCM_READ_##SIGN##BIT##_##ENDIAN(p);                \
 613                         v += Z_NORM_##BIT((intpcm64_t)x * *z_pcoeff);           \
 614                         z_pcoeff++;                                             \
 615                         p += info->channels * PCM_##BIT##_BPS;                  \
 616                         x = _PCM_READ_##SIGN##BIT##_##ENDIAN(p);                \
 617                         v += Z_NORM_##BIT((intpcm64_t)x * *z_pcoeff);           \
 618                         z_pcoeff++;                                             \
 619                         p += info->channels * PCM_##BIT##_BPS;                  \
 620                 }                                                               \
 621                 if (info->z_scale != Z_ONE)                                     \
 622                         v = Z_SCALE_##BIT(v, info->z_scale);                    \
 623                 else                                                            \
 624                         v >>= Z_COEFF_SHIFT - Z_GUARD_BIT_##BIT;                \
 625                 Z_CLIP_CHECK(v, BIT);                                           \
 626                 _PCM_WRITE_##SIGN##BIT##_##ENDIAN(dst, Z_CLAMP(v, BIT));        \
 627         } while (ch != 0);                                                      \
 628 }
 629
 630 #define Z_DECLARE(SIGN, BIT, ENDIAN)                                    \
 631         Z_DECLARE_LINEAR(SIGN, BIT, ENDIAN)                             \
 632         Z_DECLARE_SINC(SIGN, BIT, ENDIAN)                               \
 633         Z_DECLARE_SINC_POLYPHASE(SIGN, BIT, ENDIAN)
 634
 635 #if BYTE_ORDER == LITTLE_ENDIAN || defined(SND_FEEDER_MULTIFORMAT)
 636 Z_DECLARE(S, 16, LE)
 637 Z_DECLARE(S, 32, LE)
 638 #endif
 639 #if BYTE_ORDER == BIG_ENDIAN || defined(SND_FEEDER_MULTIFORMAT)
 640 Z_DECLARE(S, 16, BE)
 641 Z_DECLARE(S, 32, BE)
 642 #endif
 643 #ifdef SND_FEEDER_MULTIFORMAT
 644 Z_DECLARE(S,  8, NE)
 645 Z_DECLARE(S, 24, LE)
 646 Z_DECLARE(S, 24, BE)
 647 Z_DECLARE(U,  8, NE)
 648 Z_DECLARE(U, 16, LE)
 649 Z_DECLARE(U, 24, LE)
 650 Z_DECLARE(U, 32, LE)
 651 Z_DECLARE(U, 16, BE)
 652 Z_DECLARE(U, 24, BE)
 653 Z_DECLARE(U, 32, BE)
 654 #endif
 655
 656 enum {
 657         Z_RESAMPLER_ZOH,
 658         Z_RESAMPLER_LINEAR,
 659         Z_RESAMPLER_SINC,
 660         Z_RESAMPLER_SINC_POLYPHASE,
 661         Z_RESAMPLER_LAST
 662 };
 663
 664 #define Z_RESAMPLER_IDX(i)                                              \
 665         (Z_IS_SINC(i) ? Z_RESAMPLER_SINC : (i)->quality)
 666
 667 #define Z_RESAMPLER_ENTRY(SIGN, BIT, ENDIAN)                                    \
 668         {                                                                       \
 669             AFMT_##SIGN##BIT##_##ENDIAN,                                        \
 670             {                                                                   \
 671                 [Z_RESAMPLER_ZOH]    = z_feed_zoh,                              \
 672                 [Z_RESAMPLER_LINEAR] = z_feed_linear_##SIGN##BIT##ENDIAN,       \
 673                 [Z_RESAMPLER_SINC]   = z_feed_sinc_##SIGN##BIT##ENDIAN,         \
 674                 [Z_RESAMPLER_SINC_POLYPHASE]   =                                \
 675                     z_feed_sinc_polyphase_##SIGN##BIT##ENDIAN                   \
 676             }                                                                   \
 677         }
 678
 679 static const struct {
 680         uint32_t format;
 681         z_resampler_t resampler[Z_RESAMPLER_LAST];
 682 } z_resampler_tab[] = {
 683 #if BYTE_ORDER == LITTLE_ENDIAN || defined(SND_FEEDER_MULTIFORMAT)
 684         Z_RESAMPLER_ENTRY(S, 16, LE),
 685         Z_RESAMPLER_ENTRY(S, 32, LE),
 686 #endif
 687 #if BYTE_ORDER == BIG_ENDIAN || defined(SND_FEEDER_MULTIFORMAT)
 688         Z_RESAMPLER_ENTRY(S, 16, BE),
 689         Z_RESAMPLER_ENTRY(S, 32, BE),
 690 #endif
 691 #ifdef SND_FEEDER_MULTIFORMAT
 692         Z_RESAMPLER_ENTRY(S,  8, NE),
 693         Z_RESAMPLER_ENTRY(S, 24, LE),
 694         Z_RESAMPLER_ENTRY(S, 24, BE),
 695         Z_RESAMPLER_ENTRY(U,  8, NE),
 696         Z_RESAMPLER_ENTRY(U, 16, LE),
 697         Z_RESAMPLER_ENTRY(U, 24, LE),
 698         Z_RESAMPLER_ENTRY(U, 32, LE),
 699         Z_RESAMPLER_ENTRY(U, 16, BE),
 700         Z_RESAMPLER_ENTRY(U, 24, BE),
 701         Z_RESAMPLER_ENTRY(U, 32, BE),
 702 #endif
 703 };
 704
 705 #define Z_RESAMPLER_TAB_SIZE                                            \
 706         ((int32_t)(sizeof(z_resampler_tab) / sizeof(z_resampler_tab[0])))
 707
 708 static void
 709 z_resampler_reset(struct z_info *info)
 710 {
 711
 712         info->src = info->rsrc - (info->rsrc % ((feeder_rate_round > 0 &&
 713             info->rsrc > feeder_rate_round) ? feeder_rate_round : 1));
 714         info->dst = info->rdst - (info->rdst % ((feeder_rate_round > 0 &&
 715             info->rdst > feeder_rate_round) ? feeder_rate_round : 1));
 716         info->z_gx = 1;
 717         info->z_gy = 1;
 718         info->z_alpha = 0;
 719         info->z_resample = NULL;
 720         info->z_size = 1;
 721         info->z_coeff = NULL;
 722         info->z_dcoeff = NULL;
 723         if (info->z_pcoeff != NULL) {
 724                 free(info->z_pcoeff, M_DEVBUF);
 725                 info->z_pcoeff = NULL;
 726         }
 727         info->z_scale = Z_ONE;
 728         info->z_dx = Z_FULL_ONE;
 729         info->z_dy = Z_FULL_ONE;
 730 #ifdef Z_DIAGNOSTIC
 731         info->z_cycle = 0;
 732 #endif
 733         if (info->quality < Z_QUALITY_MIN)
 734                 info->quality = Z_QUALITY_MIN;
 735         else if (info->quality > Z_QUALITY_MAX)
 736                 info->quality = Z_QUALITY_MAX;
 737 }
 738
 739 #ifdef Z_PARANOID
 740 static int32_t
 741 z_resampler_sinc_len(struct z_info *info)
 742 {
 743         int32_t c, z, len, lmax;
 744
 745         if (!Z_IS_SINC(info))
 746                 return (1);
 747
 748         /*
 749          * A rather careful (or useless) way to calculate filter length.
 750          * Z_SINC_LEN() itself is accurate enough to do its job. Extra
 751          * sanity checking is not going to hurt though..
 752          */
 753         c = 0;
 754         z = info->z_dy;
 755         len = 0;
 756         lmax = z_coeff_tab[Z_SINC_COEFF_IDX(info)].len;
 757
 758         do {
 759                 c += z >> Z_SHIFT;
 760                 z &= Z_MASK;
 761                 z += info->z_dy;
 762         } while (c < lmax && ++len > 0);
 763
 764         if (len != Z_SINC_LEN(info)) {
 765 #ifdef _KERNEL
 766                 printf("%s(): sinc l=%d != Z_SINC_LEN=%d\n",
 767                     __func__, len, Z_SINC_LEN(info));
 768 #else
 769                 fprintf(stderr, "%s(): sinc l=%d != Z_SINC_LEN=%d\n",
 770                     __func__, len, Z_SINC_LEN(info));
 771                 return (-1);
 772 #endif
 773         }
 774
 775         return (len);
 776 }
 777 #else
 778 #define z_resampler_sinc_len(i)         (Z_IS_SINC(i) ? Z_SINC_LEN(i) : 1)
 779 #endif
 780
 781 #define Z_POLYPHASE_COEFF_SHIFT         0
 782
 783 /*
 784  * Pick suitable polynomial interpolators based on filter oversampled ratio
 785  * (2 ^ Z_DRIFT_SHIFT).
 786  */
 787 #if !(defined(Z_COEFF_INTERP_ZOH) || defined(Z_COEFF_INTERP_LINEAR) ||          \
 788     defined(Z_COEFF_INTERP_QUADRATIC) || defined(Z_COEFF_INTERP_HERMITE) ||     \
 789     defined(Z_COEFF_INTER_BSPLINE) || defined(Z_COEFF_INTERP_OPT32X) ||         \
 790     defined(Z_COEFF_INTERP_OPT16X) || defined(Z_COEFF_INTERP_OPT8X) ||          \
 791     defined(Z_COEFF_INTERP_OPT4X) || defined(Z_COEFF_INTERP_OPT2X))
 792 #if Z_DRIFT_SHIFT >= 6
 793 #define Z_COEFF_INTERP_BSPLINE          1
 794 #elif Z_DRIFT_SHIFT >= 5
 795 #define Z_COEFF_INTERP_OPT32X           1
 796 #elif Z_DRIFT_SHIFT == 4
 797 #define Z_COEFF_INTERP_OPT16X           1
 798 #elif Z_DRIFT_SHIFT == 3
 799 #define Z_COEFF_INTERP_OPT8X            1
 800 #elif Z_DRIFT_SHIFT == 2
 801 #define Z_COEFF_INTERP_OPT4X            1
 802 #elif Z_DRIFT_SHIFT == 1
 803 #define Z_COEFF_INTERP_OPT2X            1
 804 #else
 805 #error "Z_DRIFT_SHIFT screwed!"
 806 #endif
 807 #endif
 808
 809 /*
 810  * In classic polyphase mode, the actual coefficients for each phases need to
 811  * be calculated based on default prototype filters. For highly oversampled
 812  * filter, linear or quadradatic interpolator should be enough. Anything less
 813  * than that require 'special' interpolators to reduce interpolation errors.
 814  *
 815  * "Polynomial Interpolators for High-Quality Resampling of Oversampled Audio"
 816  *    by Olli Niemitalo
 817  *    - http://www.student.oulu.fi/~oniemita/dsp/deip.pdf
 818  *
 819  */
 820 static int32_t
 821 z_coeff_interpolate(int32_t z, int32_t *z_coeff)
 822 {
 823         int32_t coeff;
 824 #if defined(Z_COEFF_INTERP_ZOH)
 825
 826         /* 1-point, 0th-order (Zero Order Hold) */
 827         z = z;
 828         coeff = z_coeff[0];
 829 #elif defined(Z_COEFF_INTERP_LINEAR)
 830         int32_t zl0, zl1;
 831
 832         /* 2-point, 1st-order Linear */
 833         zl0 = z_coeff[0];
 834         zl1 = z_coeff[1] - z_coeff[0];
 835
 836         coeff = Z_RSHIFT((int64_t)zl1 * z, Z_SHIFT) + zl0;
 837 #elif defined(Z_COEFF_INTERP_QUADRATIC)
 838         int32_t zq0, zq1, zq2;
 839
 840         /* 3-point, 2nd-order Quadratic */
 841         zq0 = z_coeff[0];
 842         zq1 = z_coeff[1] - z_coeff[-1];
 843         zq2 = z_coeff[1] + z_coeff[-1] - (z_coeff[0] << 1);
 844
 845         coeff = Z_RSHIFT((Z_RSHIFT((int64_t)zq2 * z, Z_SHIFT) +
 846             zq1) * z, Z_SHIFT + 1) + zq0;
 847 #elif defined(Z_COEFF_INTERP_HERMITE)
 848         int32_t zh0, zh1, zh2, zh3;
 849
 850         /* 4-point, 3rd-order Hermite */
 851         zh0 = z_coeff[0];
 852         zh1 = z_coeff[1] - z_coeff[-1];
 853         zh2 = (z_coeff[-1] << 1) - (z_coeff[0] * 5) + (z_coeff[1] << 2) -
 854             z_coeff[2];
 855         zh3 = z_coeff[2] - z_coeff[-1] + ((z_coeff[0] - z_coeff[1]) * 3);
 856
 857         coeff = Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((int64_t)zh3 * z, Z_SHIFT) +
 858             zh2) * z, Z_SHIFT) + zh1) * z, Z_SHIFT + 1) + zh0;
 859 #elif defined(Z_COEFF_INTERP_BSPLINE)
 860         int32_t zb0, zb1, zb2, zb3;
 861
 862         /* 4-point, 3rd-order B-Spline */
 863         zb0 = Z_RSHIFT(0x15555555LL * (((int64_t)z_coeff[0] << 2) +
 864             z_coeff[-1] + z_coeff[1]), 30);
 865         zb1 = z_coeff[1] - z_coeff[-1];
 866         zb2 = z_coeff[-1] + z_coeff[1] - (z_coeff[0] << 1);
 867         zb3 = Z_RSHIFT(0x15555555LL * (((z_coeff[0] - z_coeff[1]) * 3) +
 868             z_coeff[2] - z_coeff[-1]), 30);
 869
 870         coeff = (Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((int64_t)zb3 * z, Z_SHIFT) +
 871             zb2) * z, Z_SHIFT) + zb1) * z, Z_SHIFT) + zb0 + 1) >> 1;
 872 #elif defined(Z_COEFF_INTERP_OPT32X)
 873         int32_t zoz, zoe1, zoe2, zoe3, zoo1, zoo2, zoo3;
 874         int32_t zoc0, zoc1, zoc2, zoc3, zoc4, zoc5;
 875
 876         /* 6-point, 5th-order Optimal 32x */
 877         zoz = z - (Z_ONE >> 1);
 878         zoe1 = z_coeff[1] + z_coeff[0];
 879         zoe2 = z_coeff[2] + z_coeff[-1];
 880         zoe3 = z_coeff[3] + z_coeff[-2];
 881         zoo1 = z_coeff[1] - z_coeff[0];
 882         zoo2 = z_coeff[2] - z_coeff[-1];
 883         zoo3 = z_coeff[3] - z_coeff[-2];
 884
 885         zoc0 = Z_RSHIFT((0x1ac2260dLL * zoe1) + (0x0526cdcaLL * zoe2) +
 886             (0x00170c29LL * zoe3), 30);
 887         zoc1 = Z_RSHIFT((0x14f8a49aLL * zoo1) + (0x0d6d1109LL * zoo2) +
 888             (0x008cd4dcLL * zoo3), 30);
 889         zoc2 = Z_RSHIFT((-0x0d3e94a4LL * zoe1) + (0x0bddded4LL * zoe2) +
 890             (0x0160b5d0LL * zoe3), 30);
 891         zoc3 = Z_RSHIFT((-0x0de10cc4LL * zoo1) + (0x019b2a7dLL * zoo2) +
 892             (0x01cfe914LL * zoo3), 30);
 893         zoc4 = Z_RSHIFT((0x02aa12d7LL * zoe1) + (-0x03ff1bb3LL * zoe2) +
 894             (0x015508ddLL * zoe3), 30);
 895         zoc5 = Z_RSHIFT((0x051d29e5LL * zoo1) + (-0x028e7647LL * zoo2) +
 896             (0x0082d81aLL * zoo3), 30);
 897
 898         coeff = Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT(
 899             (int64_t)zoc5 * zoz, Z_SHIFT) +
 900             zoc4) * zoz, Z_SHIFT) + zoc3) * zoz, Z_SHIFT) +
 901             zoc2) * zoz, Z_SHIFT) + zoc1) * zoz, Z_SHIFT) + zoc0;
 902 #elif defined(Z_COEFF_INTERP_OPT16X)
 903         int32_t zoz, zoe1, zoe2, zoe3, zoo1, zoo2, zoo3;
 904         int32_t zoc0, zoc1, zoc2, zoc3, zoc4, zoc5;
 905
 906         /* 6-point, 5th-order Optimal 16x */
 907         zoz = z - (Z_ONE >> 1);
 908         zoe1 = z_coeff[1] + z_coeff[0];
 909         zoe2 = z_coeff[2] + z_coeff[-1];
 910         zoe3 = z_coeff[3] + z_coeff[-2];
 911         zoo1 = z_coeff[1] - z_coeff[0];
 912         zoo2 = z_coeff[2] - z_coeff[-1];
 913         zoo3 = z_coeff[3] - z_coeff[-2];
 914
 915         zoc0 = Z_RSHIFT((0x1ac2260dLL * zoe1) + (0x0526cdcaLL * zoe2) +
 916             (0x00170c29LL * zoe3), 30);
 917         zoc1 = Z_RSHIFT((0x14f8a49aLL * zoo1) + (0x0d6d1109LL * zoo2) +
 918             (0x008cd4dcLL * zoo3), 30);
 919         zoc2 = Z_RSHIFT((-0x0d3e94a4LL * zoe1) + (0x0bddded4LL * zoe2) +
 920             (0x0160b5d0LL * zoe3), 30);
 921         zoc3 = Z_RSHIFT((-0x0de10cc4LL * zoo1) + (0x019b2a7dLL * zoo2) +
 922             (0x01cfe914LL * zoo3), 30);
 923         zoc4 = Z_RSHIFT((0x02aa12d7LL * zoe1) + (-0x03ff1bb3LL * zoe2) +
 924             (0x015508ddLL * zoe3), 30);
 925         zoc5 = Z_RSHIFT((0x051d29e5LL * zoo1) + (-0x028e7647LL * zoo2) +
 926             (0x0082d81aLL * zoo3), 30);
 927
 928         coeff = Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT(
 929             (int64_t)zoc5 * zoz, Z_SHIFT) +
 930             zoc4) * zoz, Z_SHIFT) + zoc3) * zoz, Z_SHIFT) +
 931             zoc2) * zoz, Z_SHIFT) + zoc1) * zoz, Z_SHIFT) + zoc0;
 932 #elif defined(Z_COEFF_INTERP_OPT8X)
 933         int32_t zoz, zoe1, zoe2, zoe3, zoo1, zoo2, zoo3;
 934         int32_t zoc0, zoc1, zoc2, zoc3, zoc4, zoc5;
 935
 936         /* 6-point, 5th-order Optimal 8x */
 937         zoz = z - (Z_ONE >> 1);
 938         zoe1 = z_coeff[1] + z_coeff[0];
 939         zoe2 = z_coeff[2] + z_coeff[-1];
 940         zoe3 = z_coeff[3] + z_coeff[-2];
 941         zoo1 = z_coeff[1] - z_coeff[0];
 942         zoo2 = z_coeff[2] - z_coeff[-1];
 943         zoo3 = z_coeff[3] - z_coeff[-2];
 944
 945         zoc0 = Z_RSHIFT((0x1aa9b47dLL * zoe1) + (0x053d9944LL * zoe2) +
 946             (0x0018b23fLL * zoe3), 30);
 947         zoc1 = Z_RSHIFT((0x14a104d1LL * zoo1) + (0x0d7d2504LL * zoo2) +
 948             (0x0094b599LL * zoo3), 30);
 949         zoc2 = Z_RSHIFT((-0x0d22530bLL * zoe1) + (0x0bb37a2cLL * zoe2) +
 950             (0x016ed8e0LL * zoe3), 30);
 951         zoc3 = Z_RSHIFT((-0x0d744b1cLL * zoo1) + (0x01649591LL * zoo2) +
 952             (0x01dae93aLL * zoo3), 30);
 953         zoc4 = Z_RSHIFT((0x02a7ee1bLL * zoe1) + (-0x03fbdb24LL * zoe2) +
 954             (0x0153ed07LL * zoe3), 30);
 955         zoc5 = Z_RSHIFT((0x04cf9b6cLL * zoo1) + (-0x0266b378LL * zoo2) +
 956             (0x007a7c26LL * zoo3), 30);
 957
 958         coeff = Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT(
 959             (int64_t)zoc5 * zoz, Z_SHIFT) +
 960             zoc4) * zoz, Z_SHIFT) + zoc3) * zoz, Z_SHIFT) +
 961             zoc2) * zoz, Z_SHIFT) + zoc1) * zoz, Z_SHIFT) + zoc0;
 962 #elif defined(Z_COEFF_INTERP_OPT4X)
 963         int32_t zoz, zoe1, zoe2, zoe3, zoo1, zoo2, zoo3;
 964         int32_t zoc0, zoc1, zoc2, zoc3, zoc4, zoc5;
 965
 966         /* 6-point, 5th-order Optimal 4x */
 967         zoz = z - (Z_ONE >> 1);
 968         zoe1 = z_coeff[1] + z_coeff[0];
 969         zoe2 = z_coeff[2] + z_coeff[-1];
 970         zoe3 = z_coeff[3] + z_coeff[-2];
 971         zoo1 = z_coeff[1] - z_coeff[0];
 972         zoo2 = z_coeff[2] - z_coeff[-1];
 973         zoo3 = z_coeff[3] - z_coeff[-2];
 974
 975         zoc0 = Z_RSHIFT((0x1a8eda43LL * zoe1) + (0x0556ee38LL * zoe2) +
 976             (0x001a3784LL * zoe3), 30);
 977         zoc1 = Z_RSHIFT((0x143d863eLL * zoo1) + (0x0d910e36LL * zoo2) +
 978             (0x009ca889LL * zoo3), 30);
 979         zoc2 = Z_RSHIFT((-0x0d026821LL * zoe1) + (0x0b837773LL * zoe2) +
 980             (0x017ef0c6LL * zoe3), 30);
 981         zoc3 = Z_RSHIFT((-0x0cef1502LL * zoo1) + (0x01207a8eLL * zoo2) +
 982             (0x01e936dbLL * zoo3), 30);
 983         zoc4 = Z_RSHIFT((0x029fe643LL * zoe1) + (-0x03ef3fc8LL * zoe2) +
 984             (0x014f5923LL * zoe3), 30);
 985         zoc5 = Z_RSHIFT((0x043a9d08LL * zoo1) + (-0x02154febLL * zoo2) +
 986             (0x00670dbdLL * zoo3), 30);
 987
 988         coeff = Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT(
 989             (int64_t)zoc5 * zoz, Z_SHIFT) +
 990             zoc4) * zoz, Z_SHIFT) + zoc3) * zoz, Z_SHIFT) +
 991             zoc2) * zoz, Z_SHIFT) + zoc1) * zoz, Z_SHIFT) + zoc0;
 992 #elif defined(Z_COEFF_INTERP_OPT2X)
 993         int32_t zoz, zoe1, zoe2, zoe3, zoo1, zoo2, zoo3;
 994         int32_t zoc0, zoc1, zoc2, zoc3, zoc4, zoc5;
 995
 996         /* 6-point, 5th-order Optimal 2x */
 997         zoz = z - (Z_ONE >> 1);
 998         zoe1 = z_coeff[1] + z_coeff[0];
 999         zoe2 = z_coeff[2] + z_coeff[-1];
1000         zoe3 = z_coeff[3] + z_coeff[-2];
1001         zoo1 = z_coeff[1] - z_coeff[0];
1002         zoo2 = z_coeff[2] - z_coeff[-1];
1003         zoo3 = z_coeff[3] - z_coeff[-2];
1004
1005         zoc0 = Z_RSHIFT((0x19edb6fdLL * zoe1) + (0x05ebd062LL * zoe2) +
1006             (0x00267881LL * zoe3), 30);
1007         zoc1 = Z_RSHIFT((0x1223af76LL * zoo1) + (0x0de3dd6bLL * zoo2) +
1008             (0x00d683cdLL * zoo3), 30);
1009         zoc2 = Z_RSHIFT((-0x0c3ee068LL * zoe1) + (0x0a5c3769LL * zoe2) +
1010             (0x01e2aceaLL * zoe3), 30);
1011         zoc3 = Z_RSHIFT((-0x0a8ab614LL * zoo1) + (-0x0019522eLL * zoo2) +
1012             (0x022cefc7LL * zoo3), 30);
1013         zoc4 = Z_RSHIFT((0x0276187dLL * zoe1) + (-0x03a801e8LL * zoe2) +
1014             (0x0131d935LL * zoe3), 30);
1015         zoc5 = Z_RSHIFT((0x02c373f5LL * zoo1) + (-0x01275f83LL * zoo2) +
1016             (0x0018ee79LL * zoo3), 30);
1017
1018         coeff = Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT(
1019             (int64_t)zoc5 * zoz, Z_SHIFT) +
1020             zoc4) * zoz, Z_SHIFT) + zoc3) * zoz, Z_SHIFT) +
1021             zoc2) * zoz, Z_SHIFT) + zoc1) * zoz, Z_SHIFT) + zoc0;
1022 #else
1023 #error "Interpolation type screwed!"
1024 #endif
1025
1026 #if Z_POLYPHASE_COEFF_SHIFT > 0
1027         coeff = Z_RSHIFT(coeff, Z_POLYPHASE_COEFF_SHIFT);
1028 #endif
1029         return (coeff);
1030 }
1031
1032 static int
1033 z_resampler_build_polyphase(struct z_info *info)
1034 {
1035         int32_t alpha, c, i, z, idx;
1036
1037         /* Let this be here first. */
1038         if (info->z_pcoeff != NULL) {
1039                 free(info->z_pcoeff, M_DEVBUF);
1040                 info->z_pcoeff = NULL;
1041         }
1042
1043         if (feeder_rate_polyphase_max < 1)
1044                 return (ENOTSUP);
1045
1046         if (((int64_t)info->z_size * info->z_gy * 2) >
1047             feeder_rate_polyphase_max) {
1048 #ifndef _KERNEL
1049                 fprintf(stderr, "Polyphase entries exceed: [%d/%d] %jd > %d\n",
1050                     info->z_gx, info->z_gy,
1051                     (intmax_t)info->z_size * info->z_gy * 2,
1052                     feeder_rate_polyphase_max);
1053 #endif
1054                 return (E2BIG);
1055         }
1056
1057         info->z_pcoeff = malloc(sizeof(int32_t) *
1058             info->z_size * info->z_gy * 2, M_DEVBUF, M_NOWAIT | M_ZERO);
1059         if (info->z_pcoeff == NULL)
1060                 return (ENOMEM);
1061
1062         for (alpha = 0; alpha < info->z_gy; alpha++) {
1063                 z = alpha * info->z_dx;
1064                 c = 0;
1065                 for (i = info->z_size; i != 0; i--) {
1066                         c += z >> Z_SHIFT;
1067                         z &= Z_MASK;
1068                         idx = (alpha * info->z_size * 2) +
1069                             (info->z_size * 2) - i;
1070                         info->z_pcoeff[idx] =
1071                             z_coeff_interpolate(z, info->z_coeff + c);
1072                         z += info->z_dy;
1073                 }
1074                 z = info->z_dy - (alpha * info->z_dx);
1075                 c = 0;
1076                 for (i = info->z_size; i != 0; i--) {
1077                         c += z >> Z_SHIFT;
1078                         z &= Z_MASK;
1079                         idx = (alpha * info->z_size * 2) + i - 1;
1080                         info->z_pcoeff[idx] =
1081                             z_coeff_interpolate(z, info->z_coeff + c);
1082                         z += info->z_dy;
1083                 }
1084         }
1085
1086 #ifndef _KERNEL
1087         fprintf(stderr, "Polyphase: [%d/%d] %d entries\n",
1088             info->z_gx, info->z_gy, info->z_size * info->z_gy * 2);
1089 #endif
1090
1091         return (0);
1092 }
1093
1094 static int
1095 z_resampler_setup(struct pcm_feeder *f)
1096 {
1097         struct z_info *info;
1098         int64_t gy2gx_max, gx2gy_max;
1099         uint32_t format;
1100         int32_t align, i, z_scale;
1101         int adaptive;
1102
1103         info = f->data;
1104         z_resampler_reset(info);
1105
1106         if (info->src == info->dst)
1107                 return (0);
1108
1109         /* Shrink by greatest common divisor. */
1110         i = z_gcd(info->src, info->dst);
1111         info->z_gx = info->src / i;
1112         info->z_gy = info->dst / i;
1113
1114         /* Too big, or too small. Bail out. */
1115         if (!(Z_FACTOR_SAFE(info->z_gx) && Z_FACTOR_SAFE(info->z_gy)))
1116                 return (EINVAL);
1117
1118         format = f->desc->in;
1119         adaptive = 0;
1120         z_scale = 0;
1121
1122         /*
1123          * Setup everything: filter length, conversion factor, etc.
1124          */
1125         if (Z_IS_SINC(info)) {
1126                 /*
1127                  * Downsampling, or upsampling scaling factor. As long as the
1128                  * factor can be represented by a fraction of 1 << Z_SHIFT,
1129                  * we're pretty much in business. Scaling is not needed for
1130                  * upsampling, so we just slap Z_ONE there.
1131                  */
1132                 if (info->z_gx > info->z_gy)
1133                         /*
1134                          * If the downsampling ratio is beyond sanity,
1135                          * enable semi-adaptive mode. Although handling
1136                          * extreme ratio is possible, the result of the
1137                          * conversion is just pointless, unworthy,
1138                          * nonsensical noises, etc.
1139                          */
1140                         if ((info->z_gx / info->z_gy) > Z_SINC_DOWNMAX)
1141                                 z_scale = Z_ONE / Z_SINC_DOWNMAX;
1142                         else
1143                                 z_scale = ((uint64_t)info->z_gy << Z_SHIFT) /
1144                                     info->z_gx;
1145                 else
1146                         z_scale = Z_ONE;
1147
1148                 /*
1149                  * This is actually impossible, unless anything above
1150                  * overflow.
1151                  */
1152                 if (z_scale < 1)
1153                         return (E2BIG);
1154
1155                 /*
1156                  * Calculate sample time/coefficients index drift. It is
1157                  * a constant for upsampling, but downsampling require
1158                  * heavy duty filtering with possible too long filters.
1159                  * If anything goes wrong, revisit again and enable
1160                  * adaptive mode.
1161                  */
1162 z_setup_adaptive_sinc:
1163                 if (info->z_pcoeff != NULL) {
1164                         free(info->z_pcoeff, M_DEVBUF);
1165                         info->z_pcoeff = NULL;
1166                 }
1167
1168                 if (adaptive == 0) {
1169                         info->z_dy = z_scale << Z_DRIFT_SHIFT;
1170                         if (info->z_dy < 1)
1171                                 return (E2BIG);
1172                         info->z_scale = z_scale;
1173                 } else {
1174                         info->z_dy = Z_FULL_ONE;
1175                         info->z_scale = Z_ONE;
1176                 }
1177
1178 #if 0
1179 #define Z_SCALE_DIV     10000
1180 #define Z_SCALE_LIMIT(s, v)                                             \
1181         ((((uint64_t)(s) * (v)) + (Z_SCALE_DIV >> 1)) / Z_SCALE_DIV)
1182
1183                 info->z_scale = Z_SCALE_LIMIT(info->z_scale, 9780);
1184 #endif
1185
1186                 /* Smallest drift increment. */
1187                 info->z_dx = info->z_dy / info->z_gy;
1188
1189                 /*
1190                  * Overflow or underflow. Try adaptive, let it continue and
1191                  * retry.
1192                  */
1193                 if (info->z_dx < 1) {
1194                         if (adaptive == 0) {
1195                                 adaptive = 1;
1196                                 goto z_setup_adaptive_sinc;
1197                         }
1198                         return (E2BIG);
1199                 }
1200
1201                 /*
1202                  * Round back output drift.
1203                  */
1204                 info->z_dy = info->z_dx * info->z_gy;
1205
1206                 for (i = 0; i < Z_COEFF_TAB_SIZE; i++) {
1207                         if (Z_SINC_COEFF_IDX(info) != i)
1208                                 continue;
1209                         /*
1210                          * Calculate required filter length and guard
1211                          * against possible abusive result. Note that
1212                          * this represents only 1/2 of the entire filter
1213                          * length.
1214                          */
1215                         info->z_size = z_resampler_sinc_len(info);
1216
1217                         /*
1218                          * Multiple of 2 rounding, for better accumulator
1219                          * performance.
1220                          */
1221                         info->z_size &= ~1;
1222
1223                         if (info->z_size < 2 || info->z_size > Z_SINC_MAX) {
1224                                 if (adaptive == 0) {
1225                                         adaptive = 1;
1226                                         goto z_setup_adaptive_sinc;
1227                                 }
1228                                 return (E2BIG);
1229                         }
1230                         info->z_coeff = z_coeff_tab[i].coeff + Z_COEFF_OFFSET;
1231                         info->z_dcoeff = z_coeff_tab[i].dcoeff;
1232                         break;
1233                 }
1234
1235                 if (info->z_coeff == NULL || info->z_dcoeff == NULL)
1236                         return (EINVAL);
1237         } else if (Z_IS_LINEAR(info)) {
1238                 /*
1239                  * Don't put much effort if we're doing linear interpolation.
1240                  * Just center the interpolation distance within Z_LINEAR_ONE,
1241                  * and be happy about it.
1242                  */
1243                 info->z_dx = Z_LINEAR_FULL_ONE / info->z_gy;
1244         }
1245
1246         /*
1247          * We're safe for now, lets continue.. Look for our resampler
1248          * depending on configured format and quality.
1249          */
1250         for (i = 0; i < Z_RESAMPLER_TAB_SIZE; i++) {
1251                 int ridx;
1252
1253                 if (AFMT_ENCODING(format) != z_resampler_tab[i].format)
1254                         continue;
1255                 if (Z_IS_SINC(info) && adaptive == 0 &&
1256                     z_resampler_build_polyphase(info) == 0)
1257                         ridx = Z_RESAMPLER_SINC_POLYPHASE;
1258                 else
1259                         ridx = Z_RESAMPLER_IDX(info);
1260                 info->z_resample = z_resampler_tab[i].resampler[ridx];
1261                 break;
1262         }
1263
1264         if (info->z_resample == NULL)
1265                 return (EINVAL);
1266
1267         info->bps = AFMT_BPS(format);
1268         align = info->channels * info->bps;
1269
1270         /*
1271          * Calculate largest value that can be fed into z_gy2gx() and
1272          * z_gx2gy() without causing (signed) 32bit overflow. z_gy2gx() will
1273          * be called early during feeding process to determine how much input
1274          * samples that is required to generate requested output, while
1275          * z_gx2gy() will be called just before samples filtering /
1276          * accumulation process based on available samples that has been
1277          * calculated using z_gx2gy().
1278          *
1279          * Now that is damn confusing, I guess ;-) .
1280          */
1281         gy2gx_max = (((uint64_t)info->z_gy * INT32_MAX) - info->z_gy + 1) /
1282             info->z_gx;
1283
1284         if ((gy2gx_max * align) > SND_FXDIV_MAX)
1285                 gy2gx_max = SND_FXDIV_MAX / align;
1286
1287         if (gy2gx_max < 1)
1288                 return (E2BIG);
1289
1290         gx2gy_max = (((uint64_t)info->z_gx * INT32_MAX) - info->z_gy) /
1291             info->z_gy;
1292
1293         if (gx2gy_max > INT32_MAX)
1294                 gx2gy_max = INT32_MAX;
1295
1296         if (gx2gy_max < 1)
1297                 return (E2BIG);
1298
1299         /*
1300          * Ensure that z_gy2gx() at its largest possible calculated value
1301          * (alpha = 0) will not cause overflow further late during z_gx2gy()
1302          * stage.
1303          */
1304         if (z_gy2gx(info, gy2gx_max) > _Z_GCAST(gx2gy_max))
1305                 return (E2BIG);
1306
1307         info->z_maxfeed = gy2gx_max * align;
1308
1309 #ifdef Z_USE_ALPHADRIFT
1310         info->z_startdrift = z_gy2gx(info, 1);
1311         info->z_alphadrift = z_drift(info, info->z_startdrift, 1);
1312 #endif
1313
1314         i = z_gy2gx(info, 1);
1315         info->z_full = z_roundpow2((info->z_size << 1) + i);
1316
1317         /*
1318          * Too big to be true, and overflowing left and right like mad ..
1319          */
1320         if ((info->z_full * align) < 1) {
1321                 if (adaptive == 0 && Z_IS_SINC(info)) {
1322                         adaptive = 1;
1323                         goto z_setup_adaptive_sinc;
1324                 }
1325                 return (E2BIG);
1326         }
1327
1328         /*
1329          * Increase full buffer size if its too small to reduce cyclic
1330          * buffer shifting in main conversion/feeder loop.
1331          */
1332         while (info->z_full < Z_RESERVOIR_MAX &&
1333             (info->z_full - (info->z_size << 1)) < Z_RESERVOIR)
1334                 info->z_full <<= 1;
1335
1336         /* Initialize buffer position. */
1337         info->z_mask = info->z_full - 1;
1338         info->z_start = z_prev(info, info->z_size << 1, 1);
1339         info->z_pos = z_next(info, info->z_start, 1);
1340
1341         /*
1342          * Allocate or reuse delay line buffer, whichever makes sense.
1343          */
1344         i = info->z_full * align;
1345         if (i < 1)
1346                 return (E2BIG);
1347
1348         if (info->z_delay == NULL || info->z_alloc < i ||
1349             i <= (info->z_alloc >> 1)) {
1350                 if (info->z_delay != NULL)
1351                         free(info->z_delay, M_DEVBUF);
1352                 info->z_delay = malloc(i, M_DEVBUF, M_NOWAIT | M_ZERO);
1353                 if (info->z_delay == NULL)
1354                         return (ENOMEM);
1355                 info->z_alloc = i;
1356         }
1357
1358         /*
1359          * Zero out head of buffer to avoid pops and clicks.
1360          */
1361         memset(info->z_delay, sndbuf_zerodata(f->desc->out),
1362             info->z_pos * align);
1363
1364 #ifdef Z_DIAGNOSTIC
1365         /*
1366          * XXX Debuging mess !@#$%^
1367          */
1368 #define dumpz(x)        fprintf(stderr, "\t%12s = %10u : %-11d\n",      \
1369                             "z_"__STRING(x), (uint32_t)info->z_##x,     \
1370                             (int32_t)info->z_##x)
1371         fprintf(stderr, "\n%s():\n", __func__);
1372         fprintf(stderr, "\tchannels=%d, bps=%d, format=0x%08x, quality=%d\n",
1373             info->channels, info->bps, format, info->quality);
1374         fprintf(stderr, "\t%d (%d) -> %d (%d), ",
1375             info->src, info->rsrc, info->dst, info->rdst);
1376         fprintf(stderr, "[%d/%d]\n", info->z_gx, info->z_gy);
1377         fprintf(stderr, "\tminreq=%d, ", z_gy2gx(info, 1));
1378         if (adaptive != 0)
1379                 z_scale = Z_ONE;
1380         fprintf(stderr, "factor=0x%08x/0x%08x (%f)\n",
1381             z_scale, Z_ONE, (double)z_scale / Z_ONE);
1382         fprintf(stderr, "\tbase_length=%d, ", Z_SINC_BASE_LEN(info));
1383         fprintf(stderr, "adaptive=%s\n", (adaptive != 0) ? "YES" : "NO");
1384         dumpz(size);
1385         dumpz(alloc);
1386         if (info->z_alloc < 1024)
1387                 fprintf(stderr, "\t%15s%10d Bytes\n",
1388                     "", info->z_alloc);
1389         else if (info->z_alloc < (1024 << 10))
1390                 fprintf(stderr, "\t%15s%10d KBytes\n",
1391                     "", info->z_alloc >> 10);
1392         else if (info->z_alloc < (1024 << 20))
1393                 fprintf(stderr, "\t%15s%10d MBytes\n",
1394                     "", info->z_alloc >> 20);
1395         else
1396                 fprintf(stderr, "\t%15s%10d GBytes\n",
1397                     "", info->z_alloc >> 30);
1398         fprintf(stderr, "\t%12s   %10d (min output samples)\n",
1399             "",
1400             (int32_t)z_gx2gy(info, info->z_full - (info->z_size << 1)));
1401         fprintf(stderr, "\t%12s   %10d (min allocated output samples)\n",
1402             "",
1403             (int32_t)z_gx2gy(info, (info->z_alloc / align) -
1404             (info->z_size << 1)));
1405         fprintf(stderr, "\t%12s = %10d\n",
1406             "z_gy2gx()", (int32_t)z_gy2gx(info, 1));
1407         fprintf(stderr, "\t%12s = %10d -> z_gy2gx() -> %d\n",
1408             "Max", (int32_t)gy2gx_max, (int32_t)z_gy2gx(info, gy2gx_max));
1409         fprintf(stderr, "\t%12s = %10d\n",
1410             "z_gx2gy()", (int32_t)z_gx2gy(info, 1));
1411         fprintf(stderr, "\t%12s = %10d -> z_gx2gy() -> %d\n",
1412             "Max", (int32_t)gx2gy_max, (int32_t)z_gx2gy(info, gx2gy_max));
1413         dumpz(maxfeed);
1414         dumpz(full);
1415         dumpz(start);
1416         dumpz(pos);
1417         dumpz(scale);
1418         fprintf(stderr, "\t%12s   %10f\n", "",
1419             (double)info->z_scale / Z_ONE);
1420         dumpz(dx);
1421         fprintf(stderr, "\t%12s   %10f\n", "",
1422             (double)info->z_dx / info->z_dy);
1423         dumpz(dy);
1424         fprintf(stderr, "\t%12s   %10d (drift step)\n", "",
1425             info->z_dy >> Z_SHIFT);
1426         fprintf(stderr, "\t%12s   %10d (scaling differences)\n", "",
1427             (z_scale << Z_DRIFT_SHIFT) - info->z_dy);
1428         fprintf(stderr, "\t%12s = %u bytes\n",
1429             "intpcm32_t", sizeof(intpcm32_t));
1430         fprintf(stderr, "\t%12s = 0x%08x, smallest=%.16lf\n",
1431             "Z_ONE", Z_ONE, (double)1.0 / (double)Z_ONE);
1432 #endif
1433
1434         return (0);
1435 }
1436
1437 static int
1438 z_resampler_set(struct pcm_feeder *f, int what, int32_t value)
1439 {
1440         struct z_info *info;
1441         int32_t oquality;
1442
1443         info = f->data;
1444
1445         switch (what) {
1446         case Z_RATE_SRC:
1447                 if (value < feeder_rate_min || value > feeder_rate_max)
1448                         return (E2BIG);
1449                 if (value == info->rsrc)
1450                         return (0);
1451                 info->rsrc = value;
1452                 break;
1453         case Z_RATE_DST:
1454                 if (value < feeder_rate_min || value > feeder_rate_max)
1455                         return (E2BIG);
1456                 if (value == info->rdst)
1457                         return (0);
1458                 info->rdst = value;
1459                 break;
1460         case Z_RATE_QUALITY:
1461                 if (value < Z_QUALITY_MIN || value > Z_QUALITY_MAX)
1462                         return (EINVAL);
1463                 if (value == info->quality)
1464                         return (0);
1465                 /*
1466                  * If we failed to set the requested quality, restore
1467                  * the old one. We cannot afford leaving it broken since
1468                  * passive feeder chains like vchans never reinitialize
1469                  * itself.
1470                  */
1471                 oquality = info->quality;
1472                 info->quality = value;
1473                 if (z_resampler_setup(f) == 0)
1474                         return (0);
1475                 info->quality = oquality;
1476                 break;
1477         case Z_RATE_CHANNELS:
1478                 if (value < SND_CHN_MIN || value > SND_CHN_MAX)
1479                         return (EINVAL);
1480                 if (value == info->channels)
1481                         return (0);
1482                 info->channels = value;
1483                 break;
1484         default:
1485                 return (EINVAL);
1486                 break;
1487         }
1488
1489         return (z_resampler_setup(f));
1490 }
1491
1492 static int
1493 z_resampler_get(struct pcm_feeder *f, int what)
1494 {
1495         struct z_info *info;
1496
1497         info = f->data;
1498
1499         switch (what) {
1500         case Z_RATE_SRC:
1501                 return (info->rsrc);
1502                 break;
1503         case Z_RATE_DST:
1504                 return (info->rdst);
1505                 break;
1506         case Z_RATE_QUALITY:
1507                 return (info->quality);
1508                 break;
1509         case Z_RATE_CHANNELS:
1510                 return (info->channels);
1511                 break;
1512         default:
1513                 break;
1514         }
1515
1516         return (-1);
1517 }
1518
1519 static int
1520 z_resampler_init(struct pcm_feeder *f)
1521 {
1522         struct z_info *info;
1523         int ret;
1524
1525         if (f->desc->in != f->desc->out)
1526                 return (EINVAL);
1527
1528         info = malloc(sizeof(*info), M_DEVBUF, M_NOWAIT | M_ZERO);
1529         if (info == NULL)
1530                 return (ENOMEM);
1531
1532         info->rsrc = Z_RATE_DEFAULT;
1533         info->rdst = Z_RATE_DEFAULT;
1534         info->quality = feeder_rate_quality;
1535         info->channels = AFMT_CHANNEL(f->desc->in);
1536
1537         f->data = info;
1538
1539         ret = z_resampler_setup(f);
1540         if (ret != 0) {
1541                 if (info->z_pcoeff != NULL)
1542                         free(info->z_pcoeff, M_DEVBUF);
1543                 if (info->z_delay != NULL)
1544                         free(info->z_delay, M_DEVBUF);
1545                 free(info, M_DEVBUF);
1546                 f->data = NULL;
1547         }
1548
1549         return (ret);
1550 }
1551
1552 static int
1553 z_resampler_free(struct pcm_feeder *f)
1554 {
1555         struct z_info *info;
1556
1557         info = f->data;
1558         if (info != NULL) {
1559                 if (info->z_pcoeff != NULL)
1560                         free(info->z_pcoeff, M_DEVBUF);
1561                 if (info->z_delay != NULL)
1562                         free(info->z_delay, M_DEVBUF);
1563                 free(info, M_DEVBUF);
1564         }
1565
1566         f->data = NULL;
1567
1568         return (0);
1569 }
1570
1571 static uint32_t
1572 z_resampler_feed_internal(struct pcm_feeder *f, struct pcm_channel *c,
1573     uint8_t *b, uint32_t count, void *source)
1574 {
1575         struct z_info *info;
1576         int32_t alphadrift, startdrift, reqout, ocount, reqin, align;
1577         int32_t fetch, fetched, start, cp;
1578         uint8_t *dst;
1579
1580         info = f->data;
1581         if (info->z_resample == NULL)
1582                 return (z_feed(f->source, c, b, count, source));
1583
1584         /*
1585          * Calculate sample size alignment and amount of sample output.
1586          * We will do everything in sample domain, but at the end we
1587          * will jump back to byte domain.
1588          */
1589         align = info->channels * info->bps;
1590         ocount = SND_FXDIV(count, align);
1591         if (ocount == 0)
1592                 return (0);
1593
1594         /*
1595          * Calculate amount of input samples that is needed to generate
1596          * exact amount of output.
1597          */
1598         reqin = z_gy2gx(info, ocount) - z_fetched(info);
1599
1600 #ifdef Z_USE_ALPHADRIFT
1601         startdrift = info->z_startdrift;
1602         alphadrift = info->z_alphadrift;
1603 #else
1604         startdrift = _Z_GY2GX(info, 0, 1);
1605         alphadrift = z_drift(info, startdrift, 1);
1606 #endif
1607
1608         dst = b;
1609
1610         do {
1611                 if (reqin != 0) {
1612                         fetch = z_min(z_free(info), reqin);
1613                         if (fetch == 0) {
1614                                 /*
1615                                  * No more free spaces, so wind enough
1616                                  * samples back to the head of delay line
1617                                  * in byte domain.
1618                                  */
1619                                 fetched = z_fetched(info);
1620                                 start = z_prev(info, info->z_start,
1621                                     (info->z_size << 1) - 1);
1622                                 cp = (info->z_size << 1) + fetched;
1623                                 z_copy(info->z_delay + (start * align),
1624                                     info->z_delay, cp * align);
1625                                 info->z_start =
1626                                     z_prev(info, info->z_size << 1, 1);
1627                                 info->z_pos =
1628                                     z_next(info, info->z_start, fetched + 1);
1629                                 fetch = z_min(z_free(info), reqin);
1630 #ifdef Z_DIAGNOSTIC
1631                                 if (1) {
1632                                         static uint32_t kk = 0;
1633                                         fprintf(stderr,
1634                                             "Buffer Move: "
1635                                             "start=%d fetched=%d cp=%d "
1636                                             "cycle=%u [%u]\r",
1637                                             start, fetched, cp, info->z_cycle,
1638                                             ++kk);
1639                                 }
1640                                 info->z_cycle = 0;
1641 #endif
1642                         }
1643                         if (fetch != 0) {
1644                                 /*
1645                                  * Fetch in byte domain and jump back
1646                                  * to sample domain.
1647                                  */
1648                                 fetched = SND_FXDIV(z_feed(f->source, c,
1649                                     info->z_delay + (info->z_pos * align),
1650                                     fetch * align, source), align);
1651                                 /*
1652                                  * Prepare to convert fetched buffer,
1653                                  * or mark us done if we cannot fulfill
1654                                  * the request.
1655                                  */
1656                                 reqin -= fetched;
1657                                 info->z_pos += fetched;
1658                                 if (fetched != fetch)
1659                                         reqin = 0;
1660                         }
1661                 }
1662
1663                 reqout = z_min(z_gx2gy(info, z_fetched(info)), ocount);
1664                 if (reqout != 0) {
1665                         ocount -= reqout;
1666
1667                         /*
1668                          * Drift.. drift.. drift..
1669                          *
1670                          * Notice that there are 2 methods of doing the drift
1671                          * operations: The former is much cleaner (in a sense
1672                          * of mathematical readings of my eyes), but slower
1673                          * due to integer division in z_gy2gx(). Nevertheless,
1674                          * both should give the same exact accurate drifting
1675                          * results, so the later is favourable.
1676                          */
1677                         do {
1678                                 info->z_resample(info, dst);
1679 #if 0
1680                                 startdrift = z_gy2gx(info, 1);
1681                                 alphadrift = z_drift(info, startdrift, 1);
1682                                 info->z_start += startdrift;
1683                                 info->z_alpha += alphadrift;
1684 #else
1685                                 info->z_alpha += alphadrift;
1686                                 if (info->z_alpha < info->z_gy)
1687                                         info->z_start += startdrift;
1688                                 else {
1689                                         info->z_start += startdrift - 1;
1690                                         info->z_alpha -= info->z_gy;
1691                                 }
1692 #endif
1693                                 dst += align;
1694 #ifdef Z_DIAGNOSTIC
1695                                 info->z_cycle++;
1696 #endif
1697                         } while (--reqout != 0);
1698                 }
1699         } while (reqin != 0 && ocount != 0);
1700
1701         /*
1702          * Back to byte domain..
1703          */
1704         return (dst - b);
1705 }
1706
1707 static int
1708 z_resampler_feed(struct pcm_feeder *f, struct pcm_channel *c, uint8_t *b,
1709     uint32_t count, void *source)
1710 {
1711         uint32_t feed, maxfeed, left;
1712
1713         /*
1714          * Split count to smaller chunks to avoid possible 32bit overflow.
1715          */
1716         maxfeed = ((struct z_info *)(f->data))->z_maxfeed;
1717         left = count;
1718
1719         do {
1720                 feed = z_resampler_feed_internal(f, c, b,
1721                     z_min(maxfeed, left), source);
1722                 b += feed;
1723                 left -= feed;
1724         } while (left != 0 && feed != 0);
1725
1726         return (count - left);
1727 }
1728
1729 static struct pcm_feederdesc feeder_rate_desc[] = {
1730         { FEEDER_RATE, 0, 0, 0, 0 },
1731         { 0, 0, 0, 0, 0 },
1732 };
1733
1734 static kobj_method_t feeder_rate_methods[] = {
1735         KOBJMETHOD(feeder_init,         z_resampler_init),
1736         KOBJMETHOD(feeder_free,         z_resampler_free),
1737         KOBJMETHOD(feeder_set,          z_resampler_set),
1738         KOBJMETHOD(feeder_get,          z_resampler_get),
1739         KOBJMETHOD(feeder_feed,         z_resampler_feed),
1740         KOBJMETHOD_END
1741 };
1742
1743 FEEDER_DECLARE(feeder_rate, NULL);