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/*-
* Copyright (c) 2005 Ariff Abdullah
* <skywizard@MyBSD.org.my> 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.
*
* feeder_volume, a long 'Lost Technology' rather than a new feature.
*/
#include <dev/sound/pcm/sound.h>
#include "feeder_if.h"
SND_DECLARE_FILE("$FreeBSD$");
static int
feed_volume_s16(struct pcm_feeder *f, struct pcm_channel *c, uint8_t *b,
uint32_t count, void *source)
{
int i, j, k, vol[2];
int16_t *buf;
k = FEEDER_FEED(f->source, c, b, count & ~1, source);
if (k < 2) {
#if 0
device_printf(c->dev, "%s: Not enough data (Got: %d bytes)\n",
__func__, k);
#endif
return 0;
}
#if 0
if (k & 1)
device_printf(c->dev, "%s: Bytes not 16bit aligned.\n", __func__);
#endif
k &= ~1;
i = k >> 1;
buf = (int16_t *)b;
vol[0] = c->volume & 0x7f;
vol[1] = (c->volume >> 8) & 0x7f;
while (i > 0) {
i--;
j = (vol[i & 1] * buf[i]) / 100;
if (j > 32767)
j = 32767;
if (j < -32768)
j = -32768;
buf[i] = j;
}
return k;
}
static struct pcm_feederdesc feeder_volume_s16_desc[] = {
{FEEDER_VOLUME, AFMT_S16_LE|AFMT_STEREO, AFMT_S16_LE|AFMT_STEREO, 0},
{0, 0, 0, 0},
};
static kobj_method_t feeder_volume_s16_methods[] = {
KOBJMETHOD(feeder_feed, feed_volume_s16),
{0, 0}
};
FEEDER_DECLARE(feeder_volume_s16, 2, NULL);
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