Rework PCM buffer

* Linked list instead of static array buffer pointers
* Variable sized chunks
* Improved mix handling
* Reduction in duplicated code
* Reduced IRAM usage w/o sacrificing performance
* Converted to almost entirely unsigned math
* Add pause function to reduce pcm_* exposure to playback.

This WILL break playback on the iPod until linuxstb makes a followup commit.


git-svn-id: svn://svn.rockbox.org/rockbox/trunk@8612 a1c6a512-1295-4272-9138-f99709370657

1 files changed, 3 insertions, 2 deletions

diff --git a/firmware/export/pcm_playback.h b/firmware/export/pcm_playback.h
index 5b61beb34d..a4cd93969b 100644
--- a/firmware/export/pcm_playback.h
+++ b/firmware/export/pcm_playback.h
@@ -23,10 +23,11 @@ void pcm_init(void);
 void pcm_set_frequency(unsigned int frequency);
 
 /* This is for playing "raw" PCM data */
-void pcm_play_data(void (*get_more)(unsigned char** start, long* size));
+void pcm_play_data(void (*get_more)(unsigned char** start, size_t* size),
+        unsigned char* start, size_t size);
 
 void pcm_calculate_peaks(int *left, int *right);
-long pcm_get_bytes_waiting(void);
+size_t pcm_get_bytes_waiting(void);
 
 void pcm_play_stop(void);
 void pcm_mute(bool mute);