rockbox/firmware/export/pcm-internal.h

/***************************************************************************
 *             __________               __   ___.
 *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
 *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
 *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
 *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
 *                     \/            \/     \/    \/            \/
 * $Id$
 *
 * Copyright (C) 2005 by Linus Nielsen Feltzing
 * Copyright (C) 2011 by Michael Sevakis
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
 * KIND, either express or implied.
 *
 ****************************************************************************/
#ifndef PCM_INTERNAL_H
#define PCM_INTERNAL_H

#include "config.h"

#ifdef HAVE_SW_VOLUME_CONTROL
/* Default settings - architecture may have other optimal values */

#ifndef PCM_SW_VOLUME_FRACBITS
/* Allows -73 to +6dB gain, sans large integer math */
#define PCM_SW_VOLUME_FRACBITS  (15)
#endif

/* Constants selected based on integer math overflow avoidance */
#if PCM_SW_VOLUME_FRACBITS <= 16
#define PCM_FACTOR_MAX      0x00010000u
#define PCM_FACTOR_UNITY    (1u << PCM_SW_VOLUME_FRACBITS)
#elif PCM_SW_VOLUME_FRACBITS <= 31
#define PCM_FACTOR_MAX      0x80000000u
#define PCM_FACTOR_UNITY    (1u << PCM_SW_VOLUME_FRACBITS)
#endif /* PCM_SW_VOLUME_FRACBITS */

#ifdef PCM_SW_VOLUME_UNBUFFERED
/* Copies buffer with volume scaling applied */
void pcm_sw_volume_copy_buffer(void *dst, const void *src, size_t size);
#define pcm_copy_buffer pcm_sw_volume_copy_buffer
#else /* !PCM_SW_VOLUME_UNBUFFERED */
#ifdef HAVE_SDL_AUDIO
#define pcm_copy_buffer memcpy
#endif
#ifndef PCM_PLAY_DBL_BUF_SAMPLES
#define PCM_PLAY_DBL_BUF_SAMPLES 1024 /* Max 4KByte chunks */
#endif
#ifndef PCM_DBL_BUF_BSS
#define PCM_DBL_BUF_BSS               /* In DRAM, uncached may be better */
#endif
#endif /* PCM_SW_VOLUME_UNBUFFERED */

#endif /* HAVE_SW_VOLUME_CONTROL */

#define PCM_SAMPLE_SIZE     (2 * sizeof (int16_t))
/* Cheapo buffer align macro to align to the 16-16 PCM size */
#define ALIGN_AUDIOBUF(start, size) \
    ({ (start) = (void *)(((uintptr_t)(start) + 3) & ~3); \
       (size) &= ~3; })

void pcm_do_peak_calculation(struct pcm_peaks *peaks, bool active,
                             const void *addr, int count);

/** The following are for internal use between pcm.c and target-
    specific portion **/
/* Call registered callback to obtain next buffer */
static inline bool pcm_get_more_int(const void **addr, size_t *size)
{
    extern volatile pcm_play_callback_type pcm_callback_for_more;
    pcm_play_callback_type get_more = pcm_callback_for_more;

    if (UNLIKELY(!get_more))
        return false;

    *addr = NULL;
    *size = 0;
    get_more(addr, size);
    ALIGN_AUDIOBUF(*addr, *size);

    return *addr && *size;
}

static FORCE_INLINE enum pcm_dma_status pcm_call_status_cb(
    pcm_status_callback_type callback, enum pcm_dma_status status)
{
    if (!callback)
        return status;

    return callback(status);
}

static FORCE_INLINE enum pcm_dma_status pcm_play_call_status_cb(
    enum pcm_dma_status status)
{
    extern enum pcm_dma_status
        (* volatile pcm_play_status_callback)(enum pcm_dma_status);
    return pcm_call_status_cb(pcm_play_status_callback, status);
}

static FORCE_INLINE enum pcm_dma_status
pcm_play_dma_status_callback(enum pcm_dma_status status)
{
#if defined(HAVE_SW_VOLUME_CONTROL) && !defined(PCM_SW_VOLUME_UNBUFFERED)
    extern enum pcm_dma_status
        pcm_play_dma_status_callback_int(enum pcm_dma_status status);
    return pcm_play_dma_status_callback_int(status);
#else
    return pcm_play_call_status_cb(status);
#endif /* HAVE_SW_VOLUME_CONTROL && !PCM_SW_VOLUME_UNBUFFERED */
}

#if defined(HAVE_SW_VOLUME_CONTROL) && !defined(PCM_SW_VOLUME_UNBUFFERED)
void pcm_play_dma_start_int(const void *addr, size_t size);
void pcm_play_dma_pause_int(bool pause);
void pcm_play_dma_stop_int(void);
void pcm_play_stop_int(void);
const void *pcm_play_dma_get_peak_buffer_int(int *count);
#endif /* HAVE_SW_VOLUME_CONTROL && !PCM_SW_VOLUME_UNBUFFERED */

/* Called by the bottom layer ISR when more data is needed. Returns true
 * if a new buffer is available, false otherwise. */
bool pcm_play_dma_complete_callback(enum pcm_dma_status status,
                                    const void **addr, size_t *size);

extern unsigned long pcm_curr_sampr;
extern unsigned long pcm_sampr;
extern int pcm_fsel;

#ifdef HAVE_PCM_DMA_ADDRESS
void * pcm_dma_addr(void *addr);
#endif

extern volatile bool pcm_playing;
extern volatile bool pcm_paused;

void pcm_play_dma_lock(void);
void pcm_play_dma_unlock(void);
void pcm_play_dma_init(void) INIT_ATTR;
void pcm_play_dma_postinit(void);
void pcm_play_dma_start(const void *addr, size_t size);
void pcm_play_dma_stop(void);
void pcm_play_dma_pause(bool pause);
const void * pcm_play_dma_get_peak_buffer(int *count);

void pcm_dma_apply_settings(void);

#ifdef HAVE_RECORDING

/* DMA transfer in is currently active */
extern volatile bool pcm_recording;

/* APIs implemented in the target-specific portion */
void pcm_rec_dma_init(void);
void pcm_rec_dma_close(void);
void pcm_rec_dma_start(void *addr, size_t size);
void pcm_rec_dma_stop(void);
const void * pcm_rec_dma_get_peak_buffer(void);

static FORCE_INLINE enum pcm_dma_status
pcm_rec_dma_status_callback(enum pcm_dma_status status)
{
    extern enum pcm_dma_status
        (* volatile pcm_rec_status_callback)(enum pcm_dma_status);
    return pcm_call_status_cb(pcm_rec_status_callback, status);
}


/* Called by the bottom layer ISR when more data is needed. Returns true
 * if a new buffer is available, false otherwise. */
bool pcm_rec_dma_complete_callback(enum pcm_dma_status status,
                                   void **addr, size_t *size);

#ifdef HAVE_PCM_REC_DMA_ADDRESS
#define pcm_rec_dma_addr(addr) pcm_dma_addr(addr)
#else
#define pcm_rec_dma_addr(addr) addr
#endif

#endif /* HAVE_RECORDING */

#endif /* PCM_INTERNAL_H */