firmware/export/pcm_mixer.h

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2011 by Michael Sevakis
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version 2
  15  * of the License, or (at your option) any later version.
  16  *
  17  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  18  * KIND, either express or implied.
  19  *
  20  ****************************************************************************/
  21
  22 #ifndef PCM_MIXER_H
  23 #define PCM_MIXER_H
  24
  25 /** Simple config **/
  26
  27 /* Length of PCM frames (always) */
  28 #if CONFIG_CPU == PP5002
  29 /* There's far less time to do mixing because HW FIFOs are short */
  30 #define MIX_FRAME_SAMPLES 64
  31 #else
  32 /* Assume HW DMA engine is available or sufficient latency exists in the
  33    PCM pathway */
  34 #define MIX_FRAME_SAMPLES 256
  35 #endif
  36
  37 /* IAUDIO_M5 is very tight on IRAM */
  38 #if (defined(CPU_COLDFIRE) && !defined(IAUDIO_M5)) ||  defined(CPU_PP)
  39 /* For Coldfire, it's just faster
  40    For PortalPlayer, this also avoids more expensive cache coherency */
  41 #define DOWNMIX_BUF_IBSS        IBSS_ATTR
  42 #else
  43 /* Otherwise can't DMA from IRAM, IRAM is pointless or worse */
  44 #define DOWNMIX_BUF_IBSS
  45 #endif
  46
  47 #if defined(CPU_COLDFIRE) || defined(CPU_PP)
  48 #define MIXER_CALLBACK_ICODE    ICODE_ATTR
  49 #else
  50 #define MIXER_CALLBACK_ICODE
  51 #endif
  52
  53
  54 /** Definitions **/
  55
  56 /* Channels are preassigned for simplicity */
  57 enum pcm_mixer_channel
  58 {
  59     PCM_MIXER_CHAN_PLAYBACK = 0,
  60     PCM_MIXER_CHAN_VOICE,
  61 #ifndef HAVE_HARDWARE_BEEP
  62     PCM_MIXER_CHAN_BEEP,
  63 #endif
  64     /* Add new channel indexes above this line */
  65     PCM_MIXER_NUM_CHANNELS,
  66 };
  67
  68 /* Channel playback states */
  69 enum channel_status
  70 {
  71     CHANNEL_STOPPED = 0,
  72     CHANNEL_PLAYING,
  73     CHANNEL_PAUSED,
  74 };
  75
  76 #define MIX_AMP_UNITY    0x00010000
  77 #define MIX_AMP_MUTE     0x00000000
  78
  79
  80 /** Public interfaces **/
  81
  82 /* Start playback on a channel */
  83 void mixer_channel_play_data(enum pcm_mixer_channel channel,
  84                              pcm_play_callback_type get_more,
  85                              unsigned char *start, size_t size);
  86
  87 /* Pause or resume a channel (when started) */
  88 void mixer_channel_play_pause(enum pcm_mixer_channel channel, bool play);
  89
  90 /* Stop playback on a channel */
  91 void mixer_channel_stop(enum pcm_mixer_channel channel);
  92
  93 /* Set channel's amplitude factor */
  94 void mixer_channel_set_amplitude(enum pcm_mixer_channel channel,
  95                                  unsigned int amplitude);
  96
  97 /* Return channel's playback status */
  98 enum channel_status mixer_channel_status(enum pcm_mixer_channel channel);
  99
 100 /* Returns amount data remaining in channel before next callback */
 101 size_t mixer_channel_get_bytes_waiting(enum pcm_mixer_channel channel);
 102
 103 /* Return pointer to channel's playing audio data and the size remaining */
 104 void * mixer_channel_get_buffer(enum pcm_mixer_channel channel, int *count);
 105
 106 /* Calculate peak values for channel */
 107 void mixer_channel_calculate_peaks(enum pcm_mixer_channel channel,
 108                                    int *left, int *right);
 109
 110 /* Stop ALL channels and PCM and reset state */
 111 void mixer_reset(void);
 112
 113 #endif /* PCM_MIXER_H */