/*-
 * Copyright (c) 2008-2009 Ariff Abdullah <ariff@FreeBSD.org>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifdef _KERNEL
#ifdef HAVE_KERNEL_OPTION_HEADERS
#include "opt_snd.h"
#endif
#include <dev/sound/pcm/sound.h>
#include <dev/sound/pcm/pcm.h>
#include <dev/sound/pcm/vchan.h>
#include "feeder_if.h"

#define SND_USE_FXDIV
#include "snd_fxdiv_gen.h"

SND_DECLARE_FILE("$FreeBSD: head/sys/dev/sound/pcm/feeder_mixer.c 193640 2009-06-07 19:12:08Z ariff $");
#endif

#undef SND_FEEDER_MULTIFORMAT
#define SND_FEEDER_MULTIFORMAT  1

typedef void (*feed_mixer_t)(uint8_t *, uint8_t *, uint32_t);

#define FEEDMIXER_DECLARE(SIGN, BIT, ENDIAN)                            \
static void                                                             \
feed_mixer_##SIGN##BIT##ENDIAN(uint8_t *src, uint8_t *dst,              \
    uint32_t count)                                                     \
{                                                                       \
        intpcm##BIT##_t z;                                              \
        intpcm_t x, y;                                                 \
                                                                        \
        src += count;                                                   \
        dst += count;                                                   \
                                                                        \
        do {                                                           \
                src -= PCM_##BIT##_BPS;                                 \
                dst -= PCM_##BIT##_BPS;                                 \
                count -= PCM_##BIT##_BPS;                               \
                x = PCM_READ_##SIGN##BIT##_##ENDIAN(src);               \
                y = PCM_READ_##SIGN##BIT##_##ENDIAN(dst);               \
                z = INTPCM##BIT##_T(x) + y;                             \
                x = PCM_CLAMP_##SIGN##BIT(z);                           \
                _PCM_WRITE_##SIGN##BIT##_##ENDIAN(dst, x);              \
        } while (count != 0);                                          \
}

#if BYTE_ORDER == LITTLE_ENDIAN || defined(SND_FEEDER_MULTIFORMAT)
FEEDMIXER_DECLARE(S, 16, LE)
FEEDMIXER_DECLARE(S, 32, LE)
#endif
#if BYTE_ORDER == BIG_ENDIAN || defined(SND_FEEDER_MULTIFORMAT)
FEEDMIXER_DECLARE(S, 16, BE)
FEEDMIXER_DECLARE(S, 32, BE)
#endif
#ifdef SND_FEEDER_MULTIFORMAT
FEEDMIXER_DECLARE(S,  8, NE)
FEEDMIXER_DECLARE(S, 24, LE)
FEEDMIXER_DECLARE(S, 24, BE)
FEEDMIXER_DECLARE(U,  8, NE)
FEEDMIXER_DECLARE(U, 16, LE)
FEEDMIXER_DECLARE(U, 24, LE)
FEEDMIXER_DECLARE(U, 32, LE)
FEEDMIXER_DECLARE(U, 16, BE)
FEEDMIXER_DECLARE(U, 24, BE)
FEEDMIXER_DECLARE(U, 32, BE)
#endif

struct feed_mixer_info {
        uint32_t format;
        int bps;
        feed_mixer_t mix;
};

#define FEEDMIXER_ENTRY(SIGN, BIT, ENDIAN)                              \
        {                                                               \
                AFMT_##SIGN##BIT##_##ENDIAN, PCM_##BIT##_BPS,           \
                feed_mixer_##SIGN##BIT##ENDIAN                          \
        }

static struct feed_mixer_info feed_mixer_info_tab[] = {
        FEEDMIXER_ENTRY(S,  8, NE),
#if BYTE_ORDER == LITTLE_ENDIAN || defined(SND_FEEDER_MULTIFORMAT)
        FEEDMIXER_ENTRY(S, 16, LE),
        FEEDMIXER_ENTRY(S, 32, LE),
#endif
#if BYTE_ORDER == BIG_ENDIAN || defined(SND_FEEDER_MULTIFORMAT)
        FEEDMIXER_ENTRY(S, 16, BE),
        FEEDMIXER_ENTRY(S, 32, BE),
#endif
#ifdef SND_FEEDER_MULTIFORMAT
        FEEDMIXER_ENTRY(S, 24, LE),
        FEEDMIXER_ENTRY(S, 24, BE),
        FEEDMIXER_ENTRY(U,  8, NE),
        FEEDMIXER_ENTRY(U, 16, LE),
        FEEDMIXER_ENTRY(U, 24, LE),
        FEEDMIXER_ENTRY(U, 32, LE),
        FEEDMIXER_ENTRY(U, 16, BE),
        FEEDMIXER_ENTRY(U, 24, BE),
        FEEDMIXER_ENTRY(U, 32, BE),
#endif
        {    AFMT_AC3, PCM_16_BPS, NULL },
        { AFMT_MU_LAW,  PCM_8_BPS, feed_mixer_U8NE },   /* dummy */
        {  AFMT_A_LAW,  PCM_8_BPS, feed_mixer_U8NE }    /* dummy */
};

#define FEEDMIXER_TAB_SIZE      ((int32_t)                           \
                                 (sizeof(feed_mixer_info_tab) /             \
                                  sizeof(feed_mixer_info_tab[0])))

#define FEEDMIXER_DATA(i, c)    ((void *)                          \
                                 ((uintptr_t)((((i) & 0x1f) << 5) | \
                                 ((c) & 0x1f))))
#define FEEDMIXER_INFOIDX(d)    ((uint32_t)((uintptr_t)(d) >> 5) & 0x1f)
#define FEEDMIXER_CHANNELS(d)   ((uint32_t)((uintptr_t)(d)) & 0x1f)

static int
feed_mixer_init(struct pcm_feeder *f)
{
        int i;

        if (f->desc->in != f->desc->out)
                return (EINVAL);

        for (i = 0; i < FEEDMIXER_TAB_SIZE; i++) {
                if (AFMT_ENCODING(f->desc->in) ==
                    feed_mixer_info_tab[i].format) {
                        f->data =
                            FEEDMIXER_DATA(i, AFMT_CHANNEL(f->desc->in));
                        return (0);
                }
        }

        return (EINVAL);
}

static int
feed_mixer_set(struct pcm_feeder *f, int what, int value)
{

        switch (what) {
        case FEEDMIXER_CHANNELS:
                if (value < SND_CHN_MIN || value > SND_CHN_MAX)
                        return (EINVAL);
                f->data = FEEDMIXER_DATA(FEEDMIXER_INFOIDX(f->data), value);
                break;
        default:
                return (EINVAL);
                break;
        }

        return (0);
}

static __inline int
feed_mixer_rec(struct pcm_channel *c)
{
        struct pcm_channel *ch;
        struct snd_dbuf *b, *bs;
        uint32_t cnt, maxfeed;
        int rdy;

        /*
         * Reset ready and moving pointer. We're not using bufsoft
         * anywhere since its sole purpose is to become the primary
         * distributor for the recorded buffer and also as an interrupt
         * threshold progress indicator.
         */
        b = c->bufsoft;
        b->rp = 0;
        b->rl = 0;
        cnt = sndbuf_getsize(b);
        maxfeed = SND_FXROUND(SND_FXDIV_MAX, sndbuf_getalign(b));

        do {
                cnt = FEEDER_FEED(c->feeder->source, c, b->tmpbuf,
                    min(cnt, maxfeed), c->bufhard);
                if (cnt != 0) {
                        sndbuf_acquire(b, b->tmpbuf, cnt);
                        cnt = sndbuf_getfree(b);
                }
        } while (cnt != 0);

        /* Not enough data */
        if (b->rl < sndbuf_getalign(b)) {
                b->rl = 0;
                return (0);
        }

        /*
         * Keep track of ready and moving pointer since we will use
         * bufsoft over and over again, pretending nothing has happened.
         */
        rdy = b->rl;

        CHN_FOREACH(ch, c, children.busy) {
                CHN_LOCK(ch);
                if (CHN_STOPPED(ch) || (ch->flags & CHN_F_DIRTY)) {
                        CHN_UNLOCK(ch);
                        continue;
                }
#ifdef SND_DEBUG
                if ((c->flags & CHN_F_DIRTY) && VCHAN_SYNC_REQUIRED(ch)) {
                        if (vchan_sync(ch) != 0) {
                                CHN_UNLOCK(ch);
                                continue;
                        }
                }
#endif
                bs = ch->bufsoft;
                if (ch->flags & CHN_F_MMAP)
                        sndbuf_dispose(bs, NULL, sndbuf_getready(bs));
                cnt = sndbuf_getfree(bs);
                if (cnt < sndbuf_getalign(bs)) {
                        CHN_UNLOCK(ch);
                        continue;
                }
                maxfeed = SND_FXROUND(SND_FXDIV_MAX, sndbuf_getalign(bs));
                do {
                        cnt = FEEDER_FEED(ch->feeder, ch, bs->tmpbuf,
                            min(cnt, maxfeed), b);
                        if (cnt != 0) {
                                sndbuf_acquire(bs, bs->tmpbuf, cnt);
                                cnt = sndbuf_getfree(bs);
                        }
                } while (cnt != 0);
                /*
                 * Not entirely flushed out...
                 */
                if (b->rl != 0)
                        ch->xruns++;
                CHN_UNLOCK(ch);
                /*
                 * Rewind buffer position for next virtual channel.
                 */
                b->rp = 0;
                b->rl = rdy;
        }

        /*
         * Set ready pointer to indicate that our children are ready
         * to be woken up, also as an interrupt threshold progress
         * indicator.
         */
        b->rl = 1;

        c->flags &= ~CHN_F_DIRTY;

        /*
         * Return 0 to bail out early from sndbuf_feed() loop.
         * No need to increase feedcount counter since part of this
         * feeder chains already include feed_root().
         */
        return (0);
}

static int
feed_mixer_feed(struct pcm_feeder *f, struct pcm_channel *c, uint8_t *b,
    uint32_t count, void *source)
{
        struct feed_mixer_info *info;
        struct snd_dbuf *src = source;
        struct pcm_channel *ch;
        uint32_t cnt, mcnt, rcnt, sz;
        int passthrough;
        uint8_t *tmp;

        if (c->direction == PCMDIR_REC)
                return (feed_mixer_rec(c));

        sz = sndbuf_getsize(src);
        if (sz < count)
                count = sz;

        info = &feed_mixer_info_tab[FEEDMIXER_INFOIDX(f->data)];
        sz = info->bps * FEEDMIXER_CHANNELS(f->data);
        count = SND_FXROUND(count, sz);
        if (count < sz)
                return (0);

        /*
         * We are going to use our source as a temporary buffer since it's
         * got no other purpose.  We obtain our data by traversing the channel
         * list of children and calling mixer function to mix count bytes from
         * each into our destination buffer, b.
         */
        tmp = sndbuf_getbuf(src);
        rcnt = 0;
        mcnt = 0;
        passthrough = 0;       /* 'passthrough' / 'exclusive' marker */

        CHN_FOREACH(ch, c, children.busy) {
                CHN_LOCK(ch);
                if (CHN_STOPPED(ch) || (ch->flags & CHN_F_DIRTY)) {
                        CHN_UNLOCK(ch);
                        continue;
                }
#ifdef SND_DEBUG
                if ((c->flags & CHN_F_DIRTY) && VCHAN_SYNC_REQUIRED(ch)) {
                        if (vchan_sync(ch) != 0) {
                                CHN_UNLOCK(ch);
                                continue;
                        }
                }
#endif
                if ((ch->flags & CHN_F_MMAP) && !(ch->flags & CHN_F_CLOSING))
                        sndbuf_acquire(ch->bufsoft, NULL,
                            sndbuf_getfree(ch->bufsoft));
                if (info->mix == NULL) {
                        /*
                         * Passthrough. Dump the first digital/passthrough
                         * channel into destination buffer, and the rest into
                         * nothingness (mute effect).
                         */
                        if (passthrough == 0 &&
                            (ch->format & AFMT_PASSTHROUGH)) {
                                rcnt = SND_FXROUND(FEEDER_FEED(ch->feeder, ch,
                                    b, count, ch->bufsoft), sz);
                                passthrough = 1;
                        } else
                                FEEDER_FEED(ch->feeder, ch, tmp, count,
                                    ch->bufsoft);
                } else if (c->flags & CHN_F_EXCLUSIVE) {
                        /*
                         * Exclusive. Dump the first 'exclusive' channel into
                         * destination buffer, and the rest into nothingness
                         * (mute effect).
                         */
                        if (passthrough == 0 && (ch->flags & CHN_F_EXCLUSIVE)) {
                                rcnt = SND_FXROUND(FEEDER_FEED(ch->feeder, ch,
                                    b, count, ch->bufsoft), sz);
                                passthrough = 1;
                        } else
                                FEEDER_FEED(ch->feeder, ch, tmp, count,
                                    ch->bufsoft);
                } else {
                        if (rcnt == 0) {
                                rcnt = SND_FXROUND(FEEDER_FEED(ch->feeder, ch,
                                    b, count, ch->bufsoft), sz);
                                mcnt = count - rcnt;
                        } else {
                                cnt = SND_FXROUND(FEEDER_FEED(ch->feeder, ch,
                                    tmp, count, ch->bufsoft), sz);
                                if (cnt != 0) {
                                        if (mcnt != 0) {
                                                memset(b + rcnt,
                                                    sndbuf_zerodata(
                                                    f->desc->out), mcnt);
                                                mcnt = 0;
                                        }
                                        info->mix(tmp, b, cnt);
                                        if (cnt > rcnt)
                                                rcnt = cnt;
                                }
                        }
                }
                CHN_UNLOCK(ch);
        }

        if (++c->feedcount == 0)
                c->feedcount = 2;

        c->flags &= ~CHN_F_DIRTY;

        return (rcnt);
}

static struct pcm_feederdesc feeder_mixer_desc[] = {
        { FEEDER_MIXER, 0, 0, 0, 0 },
        { 0, 0, 0, 0, 0 }
};

static kobj_method_t feeder_mixer_methods[] = {
        KOBJMETHOD(feeder_init,         feed_mixer_init),
        KOBJMETHOD(feeder_set,          feed_mixer_set),
        KOBJMETHOD(feeder_feed,         feed_mixer_feed),
        KOBJMETHOD_END
};

FEEDER_DECLARE(feeder_mixer, NULL);