Implementation done, yet to be tested.

1 files changed, 32 insertions, 39 deletions

diff --git a/src/common/tusb_fifo.h b/src/common/tusb_fifo.h
index fb0c896f3..56491c37b 100644
--- a/src/common/tusb_fifo.h
+++ b/src/common/tusb_fifo.h
@@ -52,14 +52,16 @@
  */
 typedef struct
 {
-           uint8_t* buffer    ; ///< buffer pointer
-           uint16_t depth     ; ///< max items
-           uint16_t item_size ; ///< size of each item
-           bool overwritable  ;
+           uint8_t* buffer                        ; ///< buffer pointer
+           uint16_t depth                         ; ///< max items
+           uint16_t item_size                     ; ///< size of each item
+           bool overwritable                      ;
 
-  volatile uint16_t count     ; ///< number of items in queue
-  volatile uint16_t wr_idx    ; ///< write pointer
-  volatile uint16_t rd_idx    ; ///< read pointer
+           uint16_t non_used_index_space          ; ///< required for non-power-of-two buffer length
+           uint16_t max_pointer_idx               ; ///< maximum absolute pointer index
+
+  volatile uint16_t wr_idx                        ; ///< write pointer
+  volatile uint16_t rd_idx                        ; ///< read pointer
 
 #if CFG_FIFO_MUTEX
   tu_fifo_mutex_t mutex;
@@ -67,13 +69,15 @@ typedef struct
 
 } tu_fifo_t;
 
-#define TU_FIFO_DEF(_name, _depth, _type, _overwritable) \
-  uint8_t _name##_buf[_depth*sizeof(_type)]; \
-  tu_fifo_t _name = {                        \
-      .buffer       = _name##_buf,           \
-      .depth        = _depth,                \
-      .item_size    = sizeof(_type),         \
-      .overwritable = _overwritable,         \
+#define TU_FIFO_DEF(_name, _depth, _type, _overwritable)              \
+  uint8_t _name##_buf[_depth*sizeof(_type)];                          \
+  tu_fifo_t _name = {                                                 \
+      .buffer                 = _name##_buf,                          \
+      .depth                  = _depth,                               \
+      .item_size              = sizeof(_type),                        \
+      .overwritable           = _overwritable,                        \
+      .non_used_index_space   = (2^16-1) % _depth,                    \
+      .max_pointer_idx        = (2^16-1) - ((2^16-1) % _depth),       \
   }
 
 bool tu_fifo_clear(tu_fifo_t *f);
@@ -86,39 +90,28 @@ static inline void tu_fifo_config_mutex(tu_fifo_t *f, tu_fifo_mutex_t mutex_hdl)
 }
 #endif
 
-bool     tu_fifo_write   (tu_fifo_t* f, void const * p_data);
-uint16_t tu_fifo_write_n (tu_fifo_t* f, void const * p_data, uint16_t count);
+bool     tu_fifo_write                  (tu_fifo_t* f, void const * p_data);
+uint16_t tu_fifo_write_n                (tu_fifo_t* f, void const * p_data, uint16_t count);
+
+bool     tu_fifo_read                   (tu_fifo_t* f, void * p_buffer);
+uint16_t tu_fifo_read_n                 (tu_fifo_t* f, void * p_buffer, uint16_t count);
 
-bool     tu_fifo_read    (tu_fifo_t* f, void * p_buffer);
-uint16_t tu_fifo_read_n  (tu_fifo_t* f, void * p_buffer, uint16_t count);
+bool     tu_fifo_peek_at                (tu_fifo_t* f, uint16_t pos, void * p_buffer);
+uint16_t tu_fifo_peek_at_n              (tu_fifo_t* f, uint16_t pos, void * p_buffer, uint16_t n);
 
-bool     tu_fifo_peek_at (tu_fifo_t* f, uint16_t pos, void * p_buffer);
+uint16_t tu_fifo_count                  (tu_fifo_t* f);
+void     tu_fifo_correct_read_pointer   (tu_fifo_t* f);
+bool     tu_fifo_empty                  (tu_fifo_t* f);
+bool     tu_fifo_full                   (tu_fifo_t* f);
+uint16_t tu_fifo_remaining              (tu_fifo_t* f);
+bool     tu_fifo_overflow               (tu_fifo_t* f);
+void     tu_fifo_correct_read_pointer   (tu_fifo_t* f);
 
 static inline bool tu_fifo_peek(tu_fifo_t* f, void * p_buffer)
 {
   return tu_fifo_peek_at(f, 0, p_buffer);
 }
 
-static inline bool tu_fifo_empty(tu_fifo_t* f)
-{
-  return (f->count == 0);
-}
-
-static inline bool tu_fifo_full(tu_fifo_t* f)
-{
-  return (f->count == f->depth);
-}
-
-static inline uint16_t tu_fifo_count(tu_fifo_t* f)
-{
-  return f->count;
-}
-
-static inline uint16_t tu_fifo_remaining(tu_fifo_t* f)
-{
-  return f->depth - f->count;
-}
-
 static inline uint16_t tu_fifo_depth(tu_fifo_t* f)
 {
   return f->depth;