buffer.c

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    1 /*-
    2  * Copyright (c) 2005-2009 Ariff Abdullah <ariff@FreeBSD.org>
    3  * Portions Copyright (c) Ryan Beasley <ryan.beasley@gmail.com> - GSoC 2006
    4  * Copyright (c) 1999 Cameron Grant <cg@FreeBSD.org>
    5  * All rights reserved.
    6  *
    7  * Redistribution and use in source and binary forms, with or without
    8  * modification, are permitted provided that the following conditions
    9  * are met:
   10  * 1. Redistributions of source code must retain the above copyright
   11  *    notice, this list of conditions and the following disclaimer.
   12  * 2. Redistributions in binary form must reproduce the above copyright
   13  *    notice, this list of conditions and the following disclaimer in the
   14  *    documentation and/or other materials provided with the distribution.
   15  *
   16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
   17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
   20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   26  * SUCH DAMAGE.
   27  */
   28 
   29 #ifdef HAVE_KERNEL_OPTION_HEADERS
   30 #include "opt_snd.h"
   31 #endif
   32 
   33 #include <dev/sound/pcm/sound.h>
   34 
   35 #include "feeder_if.h"
   36 
   37 #define SND_USE_FXDIV
   38 #include "snd_fxdiv_gen.h"
   39 
   40 SND_DECLARE_FILE("$FreeBSD: releng/8.0/sys/dev/sound/pcm/buffer.c 193640 2009-06-07 19:12:08Z ariff $");
   41 
   42 struct snd_dbuf *
   43 sndbuf_create(device_t dev, char *drv, char *desc, struct pcm_channel *channel)
   44 {
   45         struct snd_dbuf *b;
   46 
   47         b = malloc(sizeof(*b), M_DEVBUF, M_WAITOK | M_ZERO);
   48         snprintf(b->name, SNDBUF_NAMELEN, "%s:%s", drv, desc);
   49         b->dev = dev;
   50         b->channel = channel;
   51 
   52         return b;
   53 }
   54 
   55 void
   56 sndbuf_destroy(struct snd_dbuf *b)
   57 {
   58         sndbuf_free(b);
   59         free(b, M_DEVBUF);
   60 }
   61 
   62 bus_addr_t
   63 sndbuf_getbufaddr(struct snd_dbuf *buf)
   64 {
   65         return (buf->buf_addr);
   66 }
   67 
   68 static void
   69 sndbuf_setmap(void *arg, bus_dma_segment_t *segs, int nseg, int error)
   70 {
   71         struct snd_dbuf *b = (struct snd_dbuf *)arg;
   72 
   73         if (bootverbose) {
   74                 device_printf(b->dev, "sndbuf_setmap %lx, %lx; ",
   75                     (u_long)segs[0].ds_addr, (u_long)segs[0].ds_len);
   76                 printf("%p -> %lx\n", b->buf, (u_long)segs[0].ds_addr);
   77         }
   78         if (error == 0)
   79                 b->buf_addr = segs[0].ds_addr;
   80         else
   81                 b->buf_addr = 0;
   82 }
   83 
   84 /*
   85  * Allocate memory for DMA buffer. If the device does not use DMA transfers,
   86  * the driver can call malloc(9) and sndbuf_setup() itself.
   87  */
   88 
   89 int
   90 sndbuf_alloc(struct snd_dbuf *b, bus_dma_tag_t dmatag, int dmaflags,
   91     unsigned int size)
   92 {
   93         int ret;
   94 
   95         b->dmatag = dmatag;
   96         b->dmaflags = dmaflags | BUS_DMA_NOWAIT;
   97         b->maxsize = size;
   98         b->bufsize = b->maxsize;
   99         b->buf_addr = 0;
  100         b->flags |= SNDBUF_F_MANAGED;
  101         if (bus_dmamem_alloc(b->dmatag, (void **)&b->buf, b->dmaflags,
  102             &b->dmamap)) {
  103                 sndbuf_free(b);
  104                 return (ENOMEM);
  105         }
  106         if (bus_dmamap_load(b->dmatag, b->dmamap, b->buf, b->maxsize,
  107             sndbuf_setmap, b, 0) != 0 || b->buf_addr == 0) {
  108                 sndbuf_free(b);
  109                 return (ENOMEM);
  110         }
  111 
  112         ret = sndbuf_resize(b, 2, b->maxsize / 2);
  113         if (ret != 0)
  114                 sndbuf_free(b);
  115 
  116         return (ret);
  117 }
  118 
  119 int
  120 sndbuf_setup(struct snd_dbuf *b, void *buf, unsigned int size)
  121 {
  122         b->flags &= ~SNDBUF_F_MANAGED;
  123         if (buf)
  124                 b->flags |= SNDBUF_F_MANAGED;
  125         b->buf = buf;
  126         b->maxsize = size;
  127         b->bufsize = b->maxsize;
  128         return sndbuf_resize(b, 2, b->maxsize / 2);
  129 }
  130 
  131 void
  132 sndbuf_free(struct snd_dbuf *b)
  133 {
  134         if (b->tmpbuf)
  135                 free(b->tmpbuf, M_DEVBUF);
  136 
  137         if (b->shadbuf)
  138                 free(b->shadbuf, M_DEVBUF);
  139 
  140         if (b->buf) {
  141                 if (b->flags & SNDBUF_F_MANAGED) {
  142                         if (b->dmamap)
  143                                 bus_dmamap_unload(b->dmatag, b->dmamap);
  144                         if (b->dmatag)
  145                                 bus_dmamem_free(b->dmatag, b->buf, b->dmamap);
  146                 } else
  147                         free(b->buf, M_DEVBUF);
  148         }
  149 
  150         b->tmpbuf = NULL;
  151         b->shadbuf = NULL;
  152         b->buf = NULL;
  153         b->sl = 0;
  154         b->dmatag = NULL;
  155         b->dmamap = NULL;
  156 }
  157 
  158 #define SNDBUF_CACHE_SHIFT      5
  159 
  160 int
  161 sndbuf_resize(struct snd_dbuf *b, unsigned int blkcnt, unsigned int blksz)
  162 {
  163         unsigned int bufsize, allocsize;
  164         u_int8_t *tmpbuf;
  165 
  166         CHN_LOCK(b->channel);
  167         if (b->maxsize == 0)
  168                 goto out;
  169         if (blkcnt == 0)
  170                 blkcnt = b->blkcnt;
  171         if (blksz == 0)
  172                 blksz = b->blksz;
  173         if (blkcnt < 2 || blksz < 16 || (blkcnt * blksz) > b->maxsize) {
  174                 CHN_UNLOCK(b->channel);
  175                 return EINVAL;
  176         }
  177         if (blkcnt == b->blkcnt && blksz == b->blksz)
  178                 goto out;
  179 
  180         bufsize = blkcnt * blksz;
  181 
  182         if (bufsize > b->allocsize ||
  183             bufsize < (b->allocsize >> SNDBUF_CACHE_SHIFT)) {
  184                 allocsize = round_page(bufsize);
  185                 CHN_UNLOCK(b->channel);
  186                 tmpbuf = malloc(allocsize, M_DEVBUF, M_WAITOK);
  187                 CHN_LOCK(b->channel);
  188                 if (snd_verbose > 3)
  189                         printf("%s(): b=%p %p -> %p [%d -> %d : %d]\n",
  190                             __func__, b, b->tmpbuf, tmpbuf,
  191                             b->allocsize, allocsize, bufsize);
  192                 if (b->tmpbuf != NULL)
  193                         free(b->tmpbuf, M_DEVBUF);
  194                 b->tmpbuf = tmpbuf;
  195                 b->allocsize = allocsize;
  196         } else if (snd_verbose > 3)
  197                 printf("%s(): b=%p %d [%d] NOCHANGE\n",
  198                     __func__, b, b->allocsize, b->bufsize);
  199 
  200         b->blkcnt = blkcnt;
  201         b->blksz = blksz;
  202         b->bufsize = bufsize;
  203 
  204         sndbuf_reset(b);
  205 out:
  206         CHN_UNLOCK(b->channel);
  207         return 0;
  208 }
  209 
  210 int
  211 sndbuf_remalloc(struct snd_dbuf *b, unsigned int blkcnt, unsigned int blksz)
  212 {
  213         unsigned int bufsize, allocsize;
  214         u_int8_t *buf, *tmpbuf, *shadbuf;
  215 
  216         if (blkcnt < 2 || blksz < 16)
  217                 return EINVAL;
  218 
  219         bufsize = blksz * blkcnt;
  220 
  221         if (bufsize > b->allocsize ||
  222             bufsize < (b->allocsize >> SNDBUF_CACHE_SHIFT)) {
  223                 allocsize = round_page(bufsize);
  224                 CHN_UNLOCK(b->channel);
  225                 buf = malloc(allocsize, M_DEVBUF, M_WAITOK);
  226                 tmpbuf = malloc(allocsize, M_DEVBUF, M_WAITOK);
  227                 shadbuf = malloc(allocsize, M_DEVBUF, M_WAITOK);
  228                 CHN_LOCK(b->channel);
  229                 if (b->buf != NULL)
  230                         free(b->buf, M_DEVBUF);
  231                 b->buf = buf;
  232                 if (b->tmpbuf != NULL)
  233                         free(b->tmpbuf, M_DEVBUF);
  234                 b->tmpbuf = tmpbuf;
  235                 if (b->shadbuf != NULL)
  236                         free(b->shadbuf, M_DEVBUF);
  237                 b->shadbuf = shadbuf;
  238                 if (snd_verbose > 3)
  239                         printf("%s(): b=%p %d -> %d [%d]\n",
  240                             __func__, b, b->allocsize, allocsize, bufsize);
  241                 b->allocsize = allocsize;
  242         } else if (snd_verbose > 3)
  243                 printf("%s(): b=%p %d [%d] NOCHANGE\n",
  244                     __func__, b, b->allocsize, b->bufsize);
  245 
  246         b->blkcnt = blkcnt;
  247         b->blksz = blksz;
  248         b->bufsize = bufsize;
  249         b->maxsize = bufsize;
  250         b->sl = bufsize;
  251 
  252         sndbuf_reset(b);
  253 
  254         return 0;
  255 }
  256 
  257 /**
  258  * @brief Zero out space in buffer free area
  259  *
  260  * This function clears a chunk of @c length bytes in the buffer free area
  261  * (i.e., where the next write will be placed).
  262  *
  263  * @param b             buffer context
  264  * @param length        number of bytes to blank
  265  */
  266 void
  267 sndbuf_clear(struct snd_dbuf *b, unsigned int length)
  268 {
  269         int i;
  270         u_char data, *p;
  271 
  272         if (length == 0)
  273                 return;
  274         if (length > b->bufsize)
  275                 length = b->bufsize;
  276 
  277         data = sndbuf_zerodata(b->fmt);
  278 
  279         i = sndbuf_getfreeptr(b);
  280         p = sndbuf_getbuf(b);
  281         while (length > 0) {
  282                 p[i] = data;
  283                 length--;
  284                 i++;
  285                 if (i >= b->bufsize)
  286                         i = 0;
  287         }
  288 }
  289 
  290 /**
  291  * @brief Zap buffer contents, resetting "ready area" fields
  292  *
  293  * @param b     buffer context
  294  */
  295 void
  296 sndbuf_fillsilence(struct snd_dbuf *b)
  297 {
  298         if (b->bufsize > 0)
  299                 memset(sndbuf_getbuf(b), sndbuf_zerodata(b->fmt), b->bufsize);
  300         b->rp = 0;
  301         b->rl = b->bufsize;
  302 }
  303 
  304 /**
  305  * @brief Reset buffer w/o flushing statistics
  306  *
  307  * This function just zeroes out buffer contents and sets the "ready length"
  308  * to zero.  This was originally to facilitate minimal playback interruption
  309  * (i.e., dropped samples) in SNDCTL_DSP_SILENCE/SKIP ioctls.
  310  *
  311  * @param b     buffer context
  312  */
  313 void
  314 sndbuf_softreset(struct snd_dbuf *b)
  315 {
  316         b->rl = 0;
  317         if (b->buf && b->bufsize > 0)
  318                 sndbuf_clear(b, b->bufsize);
  319 }
  320 
  321 void
  322 sndbuf_reset(struct snd_dbuf *b)
  323 {
  324         b->hp = 0;
  325         b->rp = 0;
  326         b->rl = 0;
  327         b->dl = 0;
  328         b->prev_total = 0;
  329         b->total = 0;
  330         b->xrun = 0;
  331         if (b->buf && b->bufsize > 0)
  332                 sndbuf_clear(b, b->bufsize);
  333         sndbuf_clearshadow(b);
  334 }
  335 
  336 u_int32_t
  337 sndbuf_getfmt(struct snd_dbuf *b)
  338 {
  339         return b->fmt;
  340 }
  341 
  342 int
  343 sndbuf_setfmt(struct snd_dbuf *b, u_int32_t fmt)
  344 {
  345         b->fmt = fmt;
  346         b->bps = AFMT_BPS(b->fmt);
  347         b->align = AFMT_ALIGN(b->fmt);
  348 #if 0
  349         b->bps = AFMT_CHANNEL(b->fmt);
  350         if (b->fmt & AFMT_16BIT)
  351                 b->bps <<= 1;
  352         else if (b->fmt & AFMT_24BIT)
  353                 b->bps *= 3;
  354         else if (b->fmt & AFMT_32BIT)
  355                 b->bps <<= 2;
  356 #endif
  357         return 0;
  358 }
  359 
  360 unsigned int
  361 sndbuf_getspd(struct snd_dbuf *b)
  362 {
  363         return b->spd;
  364 }
  365 
  366 void
  367 sndbuf_setspd(struct snd_dbuf *b, unsigned int spd)
  368 {
  369         b->spd = spd;
  370 }
  371 
  372 unsigned int
  373 sndbuf_getalign(struct snd_dbuf *b)
  374 {
  375         return (b->align);
  376 }
  377 
  378 unsigned int
  379 sndbuf_getblkcnt(struct snd_dbuf *b)
  380 {
  381         return b->blkcnt;
  382 }
  383 
  384 void
  385 sndbuf_setblkcnt(struct snd_dbuf *b, unsigned int blkcnt)
  386 {
  387         b->blkcnt = blkcnt;
  388 }
  389 
  390 unsigned int
  391 sndbuf_getblksz(struct snd_dbuf *b)
  392 {
  393         return b->blksz;
  394 }
  395 
  396 void
  397 sndbuf_setblksz(struct snd_dbuf *b, unsigned int blksz)
  398 {
  399         b->blksz = blksz;
  400 }
  401 
  402 unsigned int
  403 sndbuf_getbps(struct snd_dbuf *b)
  404 {
  405         return b->bps;
  406 }
  407 
  408 void *
  409 sndbuf_getbuf(struct snd_dbuf *b)
  410 {
  411         return b->buf;
  412 }
  413 
  414 void *
  415 sndbuf_getbufofs(struct snd_dbuf *b, unsigned int ofs)
  416 {
  417         KASSERT(ofs < b->bufsize, ("%s: ofs invalid %d", __func__, ofs));
  418 
  419         return b->buf + ofs;
  420 }
  421 
  422 unsigned int
  423 sndbuf_getsize(struct snd_dbuf *b)
  424 {
  425         return b->bufsize;
  426 }
  427 
  428 unsigned int
  429 sndbuf_getmaxsize(struct snd_dbuf *b)
  430 {
  431         return b->maxsize;
  432 }
  433 
  434 unsigned int
  435 sndbuf_getallocsize(struct snd_dbuf *b)
  436 {
  437         return b->allocsize;
  438 }
  439 
  440 unsigned int
  441 sndbuf_runsz(struct snd_dbuf *b)
  442 {
  443         return b->dl;
  444 }
  445 
  446 void
  447 sndbuf_setrun(struct snd_dbuf *b, int go)
  448 {
  449         b->dl = go? b->blksz : 0;
  450 }
  451 
  452 struct selinfo *
  453 sndbuf_getsel(struct snd_dbuf *b)
  454 {
  455         return &b->sel;
  456 }
  457 
  458 /************************************************************/
  459 unsigned int
  460 sndbuf_getxrun(struct snd_dbuf *b)
  461 {
  462         SNDBUF_LOCKASSERT(b);
  463 
  464         return b->xrun;
  465 }
  466 
  467 void
  468 sndbuf_setxrun(struct snd_dbuf *b, unsigned int xrun)
  469 {
  470         SNDBUF_LOCKASSERT(b);
  471 
  472         b->xrun = xrun;
  473 }
  474 
  475 unsigned int
  476 sndbuf_gethwptr(struct snd_dbuf *b)
  477 {
  478         SNDBUF_LOCKASSERT(b);
  479 
  480         return b->hp;
  481 }
  482 
  483 void
  484 sndbuf_sethwptr(struct snd_dbuf *b, unsigned int ptr)
  485 {
  486         SNDBUF_LOCKASSERT(b);
  487 
  488         b->hp = ptr;
  489 }
  490 
  491 unsigned int
  492 sndbuf_getready(struct snd_dbuf *b)
  493 {
  494         SNDBUF_LOCKASSERT(b);
  495         KASSERT((b->rl >= 0) && (b->rl <= b->bufsize), ("%s: b->rl invalid %d", __func__, b->rl));
  496 
  497         return b->rl;
  498 }
  499 
  500 unsigned int
  501 sndbuf_getreadyptr(struct snd_dbuf *b)
  502 {
  503         SNDBUF_LOCKASSERT(b);
  504         KASSERT((b->rp >= 0) && (b->rp <= b->bufsize), ("%s: b->rp invalid %d", __func__, b->rp));
  505 
  506         return b->rp;
  507 }
  508 
  509 unsigned int
  510 sndbuf_getfree(struct snd_dbuf *b)
  511 {
  512         SNDBUF_LOCKASSERT(b);
  513         KASSERT((b->rl >= 0) && (b->rl <= b->bufsize), ("%s: b->rl invalid %d", __func__, b->rl));
  514 
  515         return b->bufsize - b->rl;
  516 }
  517 
  518 unsigned int
  519 sndbuf_getfreeptr(struct snd_dbuf *b)
  520 {
  521         SNDBUF_LOCKASSERT(b);
  522         KASSERT((b->rp >= 0) && (b->rp <= b->bufsize), ("%s: b->rp invalid %d", __func__, b->rp));
  523         KASSERT((b->rl >= 0) && (b->rl <= b->bufsize), ("%s: b->rl invalid %d", __func__, b->rl));
  524 
  525         return (b->rp + b->rl) % b->bufsize;
  526 }
  527 
  528 u_int64_t
  529 sndbuf_getblocks(struct snd_dbuf *b)
  530 {
  531         SNDBUF_LOCKASSERT(b);
  532 
  533         return b->total / b->blksz;
  534 }
  535 
  536 u_int64_t
  537 sndbuf_getprevblocks(struct snd_dbuf *b)
  538 {
  539         SNDBUF_LOCKASSERT(b);
  540 
  541         return b->prev_total / b->blksz;
  542 }
  543 
  544 u_int64_t
  545 sndbuf_gettotal(struct snd_dbuf *b)
  546 {
  547         SNDBUF_LOCKASSERT(b);
  548 
  549         return b->total;
  550 }
  551 
  552 u_int64_t
  553 sndbuf_getprevtotal(struct snd_dbuf *b)
  554 {
  555         SNDBUF_LOCKASSERT(b);
  556 
  557         return b->prev_total;
  558 }
  559 
  560 void
  561 sndbuf_updateprevtotal(struct snd_dbuf *b)
  562 {
  563         SNDBUF_LOCKASSERT(b);
  564 
  565         b->prev_total = b->total;
  566 }
  567 
  568 unsigned int
  569 snd_xbytes(unsigned int v, unsigned int from, unsigned int to)
  570 {
  571         unsigned int w, x, y;
  572 
  573         if (from == to)
  574                 return v;
  575 
  576         if (from == 0 || to == 0 || v == 0)
  577                 return 0;
  578 
  579         x = from;
  580         y = to;
  581         while (y != 0) {
  582                 w = x % y;
  583                 x = y;
  584                 y = w;
  585         }
  586         from /= x;
  587         to /= x;
  588 
  589         return (unsigned int)(((u_int64_t)v * to) / from);
  590 }
  591 
  592 unsigned int
  593 sndbuf_xbytes(unsigned int v, struct snd_dbuf *from, struct snd_dbuf *to)
  594 {
  595         if (from == NULL || to == NULL || v == 0)
  596                 return 0;
  597 
  598         return snd_xbytes(v, sndbuf_getalign(from) * sndbuf_getspd(from),
  599             sndbuf_getalign(to) * sndbuf_getspd(to));
  600 }
  601 
  602 u_int8_t
  603 sndbuf_zerodata(u_int32_t fmt)
  604 {
  605         if (fmt & (AFMT_SIGNED | AFMT_PASSTHROUGH))
  606                 return (0x00);
  607         else if (fmt & AFMT_MU_LAW)
  608                 return (0x7f);
  609         else if (fmt & AFMT_A_LAW)
  610                 return (0x55);
  611         return (0x80);
  612 }
  613 
  614 /************************************************************/
  615 
  616 /**
  617  * @brief Acquire buffer space to extend ready area
  618  *
  619  * This function extends the ready area length by @c count bytes, and may
  620  * optionally copy samples from another location stored in @c from.  The
  621  * counter @c snd_dbuf::total is also incremented by @c count bytes.
  622  *
  623  * @param b     audio buffer
  624  * @param from  sample source (optional)
  625  * @param count number of bytes to acquire
  626  *
  627  * @retval 0    Unconditional
  628  */
  629 int
  630 sndbuf_acquire(struct snd_dbuf *b, u_int8_t *from, unsigned int count)
  631 {
  632         int l;
  633 
  634         KASSERT(count <= sndbuf_getfree(b), ("%s: count %d > free %d", __func__, count, sndbuf_getfree(b)));
  635         KASSERT((b->rl >= 0) && (b->rl <= b->bufsize), ("%s: b->rl invalid %d", __func__, b->rl));
  636         b->total += count;
  637         if (from != NULL) {
  638                 while (count > 0) {
  639                         l = min(count, sndbuf_getsize(b) - sndbuf_getfreeptr(b));
  640                         bcopy(from, sndbuf_getbufofs(b, sndbuf_getfreeptr(b)), l);
  641                         from += l;
  642                         b->rl += l;
  643                         count -= l;
  644                 }
  645         } else
  646                 b->rl += count;
  647         KASSERT((b->rl >= 0) && (b->rl <= b->bufsize), ("%s: b->rl invalid %d, count %d", __func__, b->rl, count));
  648 
  649         return 0;
  650 }
  651 
  652 /**
  653  * @brief Dispose samples from channel buffer, increasing size of ready area
  654  *
  655  * This function discards samples from the supplied buffer by advancing the
  656  * ready area start pointer and decrementing the ready area length.  If 
  657  * @c to is not NULL, then the discard samples will be copied to the location
  658  * it points to.
  659  *
  660  * @param b     PCM channel sound buffer
  661  * @param to    destination buffer (optional)
  662  * @param count number of bytes to discard
  663  *
  664  * @returns 0 unconditionally
  665  */
  666 int
  667 sndbuf_dispose(struct snd_dbuf *b, u_int8_t *to, unsigned int count)
  668 {
  669         int l;
  670 
  671         KASSERT(count <= sndbuf_getready(b), ("%s: count %d > ready %d", __func__, count, sndbuf_getready(b)));
  672         KASSERT((b->rl >= 0) && (b->rl <= b->bufsize), ("%s: b->rl invalid %d", __func__, b->rl));
  673         if (to != NULL) {
  674                 while (count > 0) {
  675                         l = min(count, sndbuf_getsize(b) - sndbuf_getreadyptr(b));
  676                         bcopy(sndbuf_getbufofs(b, sndbuf_getreadyptr(b)), to, l);
  677                         to += l;
  678                         b->rl -= l;
  679                         b->rp = (b->rp + l) % b->bufsize;
  680                         count -= l;
  681                 }
  682         } else {
  683                 b->rl -= count;
  684                 b->rp = (b->rp + count) % b->bufsize;
  685         }
  686         KASSERT((b->rl >= 0) && (b->rl <= b->bufsize), ("%s: b->rl invalid %d, count %d", __func__, b->rl, count));
  687 
  688         return 0;
  689 }
  690 
  691 #ifdef SND_DIAGNOSTIC
  692 static uint32_t snd_feeder_maxfeed = 0;
  693 SYSCTL_INT(_hw_snd, OID_AUTO, feeder_maxfeed, CTLFLAG_RD,
  694     &snd_feeder_maxfeed, 0, "maximum feeder count request");
  695 
  696 static uint32_t snd_feeder_maxcycle = 0;
  697 SYSCTL_INT(_hw_snd, OID_AUTO, feeder_maxcycle, CTLFLAG_RD,
  698     &snd_feeder_maxcycle, 0, "maximum feeder cycle");
  699 #endif
  700 
  701 /* count is number of bytes we want added to destination buffer */
  702 int
  703 sndbuf_feed(struct snd_dbuf *from, struct snd_dbuf *to, struct pcm_channel *channel, struct pcm_feeder *feeder, unsigned int count)
  704 {
  705         unsigned int cnt, maxfeed;
  706 #ifdef SND_DIAGNOSTIC
  707         unsigned int cycle;
  708 
  709         if (count > snd_feeder_maxfeed)
  710                 snd_feeder_maxfeed = count;
  711 
  712         cycle = 0;
  713 #endif
  714 
  715         KASSERT(count > 0, ("can't feed 0 bytes"));
  716 
  717         if (sndbuf_getfree(to) < count)
  718                 return (EINVAL);
  719 
  720         maxfeed = SND_FXROUND(SND_FXDIV_MAX, sndbuf_getalign(to));
  721 
  722         do {
  723                 cnt = FEEDER_FEED(feeder, channel, to->tmpbuf,
  724                     min(count, maxfeed), from);
  725                 if (cnt == 0)
  726                         break;
  727                 sndbuf_acquire(to, to->tmpbuf, cnt);
  728                 count -= cnt;
  729 #ifdef SND_DIAGNOSTIC
  730                 cycle++;
  731 #endif
  732         } while (count != 0);
  733 
  734 #ifdef SND_DIAGNOSTIC
  735         if (cycle > snd_feeder_maxcycle)
  736                 snd_feeder_maxcycle = cycle;
  737 #endif
  738 
  739         return (0);
  740 }
  741 
  742 /************************************************************/
  743 
  744 void
  745 sndbuf_dump(struct snd_dbuf *b, char *s, u_int32_t what)
  746 {
  747         printf("%s: [", s);
  748         if (what & 0x01)
  749                 printf(" bufsize: %d, maxsize: %d", b->bufsize, b->maxsize);
  750         if (what & 0x02)
  751                 printf(" dl: %d, rp: %d, rl: %d, hp: %d", b->dl, b->rp, b->rl, b->hp);
  752         if (what & 0x04)
  753                 printf(" total: %ju, prev_total: %ju, xrun: %d", (uintmax_t)b->total, (uintmax_t)b->prev_total, b->xrun);
  754         if (what & 0x08)
  755                 printf(" fmt: 0x%x, spd: %d", b->fmt, b->spd);
  756         if (what & 0x10)
  757                 printf(" blksz: %d, blkcnt: %d, flags: 0x%x", b->blksz, b->blkcnt, b->flags);
  758         printf(" ]\n");
  759 }
  760 
  761 /************************************************************/
  762 u_int32_t
  763 sndbuf_getflags(struct snd_dbuf *b)
  764 {
  765         return b->flags;
  766 }
  767 
  768 void
  769 sndbuf_setflags(struct snd_dbuf *b, u_int32_t flags, int on)
  770 {
  771         b->flags &= ~flags;
  772         if (on)
  773                 b->flags |= flags;
  774 }
  775 
  776 /**
  777  * @brief Clear the shadow buffer by filling with samples equal to zero.
  778  *
  779  * @param b buffer to clear
  780  */
  781 void
  782 sndbuf_clearshadow(struct snd_dbuf *b)
  783 {
  784         KASSERT(b != NULL, ("b is a null pointer"));
  785         KASSERT(b->sl >= 0, ("illegal shadow length"));
  786 
  787         if ((b->shadbuf != NULL) && (b->sl > 0))
  788                 memset(b->shadbuf, sndbuf_zerodata(b->fmt), b->sl);
  789 }
  790 
  791 #ifdef OSSV4_EXPERIMENT
  792 /**
  793  * @brief Return peak value from samples in buffer ready area.
  794  *
  795  * Peak ranges from 0-32767.  If channel is monaural, most significant 16
  796  * bits will be zero.  For now, only expects to work with 1-2 channel
  797  * buffers.
  798  *
  799  * @note  Currently only operates with linear PCM formats.
  800  *
  801  * @param b buffer to analyze
  802  * @param lpeak pointer to store left peak value
  803  * @param rpeak pointer to store right peak value
  804  */
  805 void
  806 sndbuf_getpeaks(struct snd_dbuf *b, int *lp, int *rp)
  807 {
  808         u_int32_t lpeak, rpeak;
  809 
  810         lpeak = 0;
  811         rpeak = 0;
  812 
  813         /**
  814          * @todo fill this in later
  815          */
  816 }
  817 #endif
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FreeBSD/Linux Kernel Cross Reference sys/dev/sound/pcm/buffer.c

FreeBSD/Linux Kernel Cross Reference
sys/dev/sound/pcm/buffer.c
