diff --git a/src/common/tusb_fifo.c b/src/common/tusb_fifo.c
index e3c4d74c..30629af7 100644
--- a/src/common/tusb_fifo.c
+++ b/src/common/tusb_fifo.c
@@ -598,6 +598,8 @@ bool tu_fifo_clear(tu_fifo_t *f)
 {
   tu_fifo_lock(f);
   f->rd_idx = f->wr_idx = 0;
+  f->max_pointer_idx = 2*f->depth-1;
+  f->non_used_index_space = UINT16_MAX - f->max_pointer_idx;
   tu_fifo_unlock(f);
 
   return true;
diff --git a/src/common/tusb_fifo.h b/src/common/tusb_fifo.h
index c35b85a4..29437849 100644
--- a/src/common/tusb_fifo.h
+++ b/src/common/tusb_fifo.h
@@ -66,8 +66,8 @@ typedef struct
   uint16_t item_size                     ; ///< size of each item
   bool overwritable                      ;
 
-  uint16_t non_used_index_space          ; ///< required for non-power-of-two buffer length
   uint16_t max_pointer_idx               ; ///< maximum absolute pointer index
+  uint16_t non_used_index_space          ; ///< required for non-power-of-two buffer length
 
   volatile uint16_t wr_idx               ; ///< write pointer
   volatile uint16_t rd_idx               ; ///< read pointer
@@ -78,16 +78,19 @@ 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,                        \
-        .max_pointer_idx        = 2*_depth-1,                           \
-        .non_used_index_space   = UINT16_MAX - (2*_depth-1),                  \
-    }
+#define TU_FIFO_INIT(_buffer, _depth, _type, _overwritable) \
+{                                                           \
+  .buffer               = _buffer,                          \
+  .depth                = _depth,                           \
+  .item_size            = sizeof(_type),                    \
+  .overwritable         = _overwritable,                    \
+  .max_pointer_idx      = 2*(_depth)-1,                     \
+  .non_used_index_space = UINT16_MAX - (2*(_depth)-1)       \
+}
+
+#define TU_FIFO_DEF(_name, _depth, _type, _overwritable)                      \
+    uint8_t _name##_buf[_depth*sizeof(_type)];                                \
+    tu_fifo_t _name = TU_FIFO_INIT(_name##_buf, _depth, _type, _overwritable)
 
 bool tu_fifo_set_overwritable(tu_fifo_t *f, bool overwritable);
 bool tu_fifo_clear(tu_fifo_t *f);
diff --git a/src/osal/osal_none.h b/src/osal/osal_none.h
index 1d170d2f..ea681862 100644
--- a/src/osal/osal_none.h
+++ b/src/osal/osal_none.h
@@ -130,18 +130,11 @@ typedef struct
 typedef osal_queue_def_t* osal_queue_t;
 
 // role device/host is used by OS NONE for mutex (disable usb isr) only
-#define OSAL_QUEUE_DEF(_role, _name, _depth, _type) \
-  uint8_t _name##_buf[_depth*sizeof(_type)];        \
-  osal_queue_def_t _name = {                        \
-    .role = _role,                                  \
-    .ff = {                                         \
-      .buffer       = _name##_buf,                  \
-      .depth        = _depth,                       \
-      .item_size    = sizeof(_type),                \
-      .overwritable = false,                        \
-      .max_pointer_idx = (2*(_depth))-1,            \
-      .non_used_index_space = 0xFFFF-((2*(_depth))-1),\
-    }\
+#define OSAL_QUEUE_DEF(_role, _name, _depth, _type)       \
+  uint8_t _name##_buf[_depth*sizeof(_type)];              \
+  osal_queue_def_t _name = {                              \
+    .role = _role,                                        \
+    .ff = TU_FIFO_INIT(_name##_buf, _depth, _type, false) \
   }
 
 // lock queue by disable USB interrupt
diff --git a/src/osal/osal_pico.h b/src/osal/osal_pico.h
index 79054ddf..de964a7a 100644
--- a/src/osal/osal_pico.h
+++ b/src/osal/osal_pico.h
@@ -115,17 +115,10 @@ typedef struct
 typedef osal_queue_def_t* osal_queue_t;
 
 // role device/host is used by OS NONE for mutex (disable usb isr) only
-#define OSAL_QUEUE_DEF(_role, _name, _depth, _type) \
-  uint8_t _name##_buf[_depth*sizeof(_type)];        \
-  osal_queue_def_t _name = {                        \
-    .ff = {                                         \
-      .buffer       = _name##_buf,                  \
-      .depth        = _depth,                       \
-      .item_size    = sizeof(_type),                \
-      .overwritable = false,                        \
-       .max_pointer_idx        = 2*_depth-1,                           \
-      .non_used_index_space   = UINT16_MAX - (2*_depth-1),                  \
-    }\
+#define OSAL_QUEUE_DEF(_role, _name, _depth, _type)       \
+  uint8_t _name##_buf[_depth*sizeof(_type)];              \
+  osal_queue_def_t _name = {                              \
+    .ff = TU_FIFO_INIT(_name##_buf, _depth, _type, false) \
   }
 
 // lock queue by disable USB interrupt