/*      $NetBSD: linear.c,v 1.5 2024/04/20 05:38:40 isaki Exp $ */

/*
* Copyright (C) 2017 Tetsuya Isaki. All rights reserved.
* Copyright (C) 2017 Y.Sugahara (moveccr). 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 ``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 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.
*/

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: linear.c,v 1.5 2024/04/20 05:38:40 isaki Exp $");

#include <sys/param.h>
#include <sys/types.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <dev/audio/audiovar.h>
#include <dev/audio/linear.h>

/*
* audio_linear8_to_internal:
*      This filter performs conversion from [US]LINEAR8 to internal format.
*/
void
audio_linear8_to_internal(audio_filter_arg_t *arg)
{
       const uint8_t *s;
       aint_t *d;
       uint8_t xor;
       u_int sample_count;
       u_int i;

       DIAGNOSTIC_filter_arg(arg);
       KASSERT(audio_format2_is_linear(arg->srcfmt));
       KASSERT(arg->srcfmt->precision == 8);
       KASSERT(arg->srcfmt->stride == 8);
       KASSERT(audio_format2_is_internal(arg->dstfmt));
       KASSERT(arg->srcfmt->channels == arg->dstfmt->channels);

       s = arg->src;
       d = arg->dst;
       sample_count = arg->count * arg->srcfmt->channels;
       xor = audio_format2_is_signed(arg->srcfmt) ? 0 : 0x80;

       for (i = 0; i < sample_count; i++) {
               uint8_t val;
               val = *s++;
               val ^= xor;
               *d++ = (auint_t)val << (AUDIO_INTERNAL_BITS - 8);
       }
}

/*
* audio_internal_to_linear8:
*      This filter performs conversion from internal format to [US]LINEAR8.
*/
void
audio_internal_to_linear8(audio_filter_arg_t *arg)
{
       const aint_t *s;
       uint8_t *d;
       uint8_t xor;
       u_int sample_count;
       u_int i;

       DIAGNOSTIC_filter_arg(arg);
       KASSERT(audio_format2_is_linear(arg->dstfmt));
       KASSERT(arg->dstfmt->precision == 8);
       KASSERT(arg->dstfmt->stride == 8);
       KASSERT(audio_format2_is_internal(arg->srcfmt));
       KASSERT(arg->srcfmt->channels == arg->dstfmt->channels);

       s = arg->src;
       d = arg->dst;
       sample_count = arg->count * arg->srcfmt->channels;
       xor = audio_format2_is_signed(arg->dstfmt) ? 0 : 0x80;

       for (i = 0; i < sample_count; i++) {
               uint8_t val;
               val = (*s++) >> (AUDIO_INTERNAL_BITS - 8);
               val ^= xor;
               *d++ = val;
       }
}

/*
* audio_linear16_to_internal:
*      This filter performs conversion from [US]LINEAR16{LE,BE} to internal
*      format.
*/
void
audio_linear16_to_internal(audio_filter_arg_t *arg)
{
       const uint16_t *s;
       aint_t *d;
       uint16_t xor;
       u_int sample_count;
       u_int shift;
       u_int i;
       bool is_src_NE;

       DIAGNOSTIC_filter_arg(arg);
       KASSERT(audio_format2_is_linear(arg->srcfmt));
       KASSERT(arg->srcfmt->precision == 16);
       KASSERT(arg->srcfmt->stride == 16);
       KASSERT(audio_format2_is_internal(arg->dstfmt));
       KASSERT(arg->srcfmt->channels == arg->dstfmt->channels);

       s = arg->src;
       d = arg->dst;
       sample_count = arg->count * arg->srcfmt->channels;

       shift = AUDIO_INTERNAL_BITS - 16;
       xor = audio_format2_is_signed(arg->srcfmt) ? 0 : 0x8000;
       is_src_NE = (audio_format2_endian(arg->srcfmt) == BYTE_ORDER);

       /*
        * Since slinear16_OppositeEndian to slinear_NativeEndian is used
        * so much especially on big endian machines, so it's expanded.
        * Other conversions are rarely used, so they are compressed.
        */
       if (__predict_true(xor == 0) && is_src_NE == false) {
               /* slinear16_OE to slinear<AI>_NE */
               for (i = 0; i < sample_count; i++) {
                       uint16_t val;
                       val = *s++;
                       val = bswap16(val);
                       *d++ = (auint_t)val << shift;
               }
       } else {
               /* slinear16_NE      to slinear<AI>_NE */
               /* ulinear16_{NE,OE} to slinear<AI>_NE */
               for (i = 0; i < sample_count; i++) {
                       uint16_t val;
                       val = *s++;
                       if (!is_src_NE)
                               val = bswap16(val);
                       val ^= xor;
                       *d++ = (auint_t)val << shift;
               }
       }
}

/*
* audio_internal_to_linear16:
*      This filter performs conversion from internal format to
*      [US]LINEAR16{LE,BE}.
*/
void
audio_internal_to_linear16(audio_filter_arg_t *arg)
{
       const aint_t *s;
       uint16_t *d;
       uint16_t xor;
       u_int sample_count;
       u_int shift;
       u_int i;
       bool is_dst_NE;

       DIAGNOSTIC_filter_arg(arg);
       KASSERT(audio_format2_is_linear(arg->dstfmt));
       KASSERT(arg->dstfmt->precision == 16);
       KASSERT(arg->dstfmt->stride == 16);
       KASSERT(audio_format2_is_internal(arg->srcfmt));
       KASSERT(arg->srcfmt->channels == arg->dstfmt->channels);

       s = arg->src;
       d = arg->dst;
       sample_count = arg->count * arg->srcfmt->channels;

       shift = AUDIO_INTERNAL_BITS - 16;
       xor = audio_format2_is_signed(arg->dstfmt) ? 0 : 0x8000;
       is_dst_NE = (audio_format2_endian(arg->dstfmt) == BYTE_ORDER);

       /*
        * Since slinear_NativeEndian to slinear16_OppositeEndian is used
        * so much especially on big endian machines, so it's expanded.
        * Other conversions are rarely used, so they are compressed.
        */
       if (__predict_true(xor == 0) && is_dst_NE == false) {
               /* slinear<AI>_NE -> slinear16_OE */
               for (i = 0; i < sample_count; i++) {
                       uint16_t val;
                       val = (*s++) >> shift;
                       val = bswap16(val);
                       *d++ = val;
               }
       } else {
               /* slinear<AI>_NE -> slinear16_NE */
               /* slinear<AI>_NE -> ulinear16_{NE,OE} */
               for (i = 0; i < sample_count; i++) {
                       uint16_t val;
                       val = (*s++) >> shift;
                       val ^= xor;
                       if (!is_dst_NE)
                               val = bswap16(val);
                       *d++ = val;
               }
       }
}

#if defined(AUDIO_SUPPORT_LINEAR24)
/*
* audio_linear24_to_internal:
*      This filter performs conversion from [US]LINEAR24/24{LE,BE} to
*      internal format.  Since it's rarely used, it's size optimized.
*/
void
audio_linear24_to_internal(audio_filter_arg_t *arg)
{
       const uint8_t *s;
       aint_t *d;
       auint_t xor;
       u_int sample_count;
       u_int i;
       bool is_src_LE;

       DIAGNOSTIC_filter_arg(arg);
       KASSERT(audio_format2_is_linear(arg->srcfmt));
       KASSERT(arg->srcfmt->precision == 24);
       KASSERT(arg->srcfmt->stride == 24);
       KASSERT(audio_format2_is_internal(arg->dstfmt));
       KASSERT(arg->srcfmt->channels == arg->dstfmt->channels);

       s = arg->src;
       d = arg->dst;
       sample_count = arg->count * arg->srcfmt->channels;
       xor = audio_format2_is_signed(arg->srcfmt)
           ? 0 : (1 << (AUDIO_INTERNAL_BITS - 1));
       is_src_LE = (audio_format2_endian(arg->srcfmt) == LITTLE_ENDIAN);

       for (i = 0; i < sample_count; i++) {
               uint32_t val;
               if (is_src_LE) {
                       val = s[0] | (s[1] << 8) | (s[2] << 16);
               } else {
                       val = (s[0] << 16) | (s[1] << 8) | s[2];
               }
               s += 3;

#if AUDIO_INTERNAL_BITS < 24
               val >>= 24 - AUDIO_INTERNAL_BITS;
#else
               val <<= AUDIO_INTERNAL_BITS - 24;
#endif
               val ^= xor;
               *d++ = val;
       }
}

/*
* audio_internal_to_linear24:
*      This filter performs conversion from internal format to
*      [US]LINEAR24/24{LE,BE}.  Since it's rarely used, it's size optimized.
*/
void
audio_internal_to_linear24(audio_filter_arg_t *arg)
{
       const aint_t *s;
       uint8_t *d;
       auint_t xor;
       u_int sample_count;
       u_int i;
       bool is_dst_LE;

       DIAGNOSTIC_filter_arg(arg);
       KASSERT(audio_format2_is_linear(arg->dstfmt));
       KASSERT(arg->dstfmt->precision == 24);
       KASSERT(arg->dstfmt->stride == 24);
       KASSERT(audio_format2_is_internal(arg->srcfmt));
       KASSERT(arg->srcfmt->channels == arg->dstfmt->channels);

       s = arg->src;
       d = arg->dst;
       sample_count = arg->count * arg->srcfmt->channels;
       xor = audio_format2_is_signed(arg->dstfmt)
           ? 0 : (1 << (AUDIO_INTERNAL_BITS - 1));
       is_dst_LE = (audio_format2_endian(arg->dstfmt) == LITTLE_ENDIAN);

       for (i = 0; i < sample_count; i++) {
               uint32_t val;
               val = *s++;
               val ^= xor;
#if AUDIO_INTERNAL_BITS < 24
               val <<= 24 - AUDIO_INTERNAL_BITS;
#else
               val >>= AUDIO_INTERNAL_BITS - 24;
#endif
               if (is_dst_LE) {
                       d[0] = val & 0xff;
                       d[1] = (val >> 8) & 0xff;
                       d[2] = (val >> 16) & 0xff;
               } else {
                       d[0] = (val >> 16) & 0xff;
                       d[1] = (val >> 8) & 0xff;
                       d[2] = val & 0xff;
               }
               d += 3;
       }
}
#endif /* AUDIO_SUPPORT_LINEAR24 */

/*
* audio_linear32_to_internal:
*      This filter performs conversion from [US]LINEAR32{LE,BE} to internal
*      format.  Since it's rarely used, it's size optimized.
*/
void
audio_linear32_to_internal(audio_filter_arg_t *arg)
{
       const uint32_t *s;
       aint_t *d;
       auint_t xor;
       u_int sample_count;
       u_int i;
       bool is_src_NE;

       DIAGNOSTIC_filter_arg(arg);
       KASSERT(audio_format2_is_linear(arg->srcfmt));
       KASSERT(arg->srcfmt->precision == 32);
       KASSERT(arg->srcfmt->stride == 32);
       KASSERT(audio_format2_is_internal(arg->dstfmt));
       KASSERT(arg->srcfmt->channels == arg->dstfmt->channels);

       s = arg->src;
       d = arg->dst;
       sample_count = arg->count * arg->srcfmt->channels;
       xor = audio_format2_is_signed(arg->srcfmt)
           ? 0 : (1 << (AUDIO_INTERNAL_BITS - 1));
       is_src_NE = (audio_format2_endian(arg->srcfmt) == BYTE_ORDER);

       for (i = 0; i < sample_count; i++) {
               uint32_t val;
               val = *s++;
               if (!is_src_NE)
                       val = bswap32(val);
               val >>= 32 - AUDIO_INTERNAL_BITS;
               val ^= xor;
               *d++ = val;
       }
}

/*
* audio_internal_to_linear32:
*      This filter performs conversion from internal format to
*      [US]LINEAR32{LE,BE}.  Since it's rarely used, it's size optimized.
*/
void
audio_internal_to_linear32(audio_filter_arg_t *arg)
{
       const aint_t *s;
       uint32_t *d;
       auint_t xor;
       u_int sample_count;
       u_int i;
       bool is_dst_NE;

       DIAGNOSTIC_filter_arg(arg);
       KASSERT(audio_format2_is_linear(arg->dstfmt));
       KASSERT(arg->dstfmt->precision == 32);
       KASSERT(arg->dstfmt->stride == 32);
       KASSERT(audio_format2_is_internal(arg->srcfmt));
       KASSERT(arg->srcfmt->channels == arg->dstfmt->channels);

       s = arg->src;
       d = arg->dst;
       sample_count = arg->count * arg->srcfmt->channels;
       xor = audio_format2_is_signed(arg->dstfmt)
           ? 0 : (1 << (AUDIO_INTERNAL_BITS - 1));
       is_dst_NE = (audio_format2_endian(arg->dstfmt) == BYTE_ORDER);

       for (i = 0; i < sample_count; i++) {
               uint32_t val;
               val = *s++;
               val ^= xor;
               val <<= 32 - AUDIO_INTERNAL_BITS;
               if (!is_dst_NE)
                       val = bswap32(val);
               *d++ = val;
       }
}