Use buflib for the allocation of voice PCM resources.

Buffers are not allocated and thread is not created until the first
call where voice is required.

Adds a different callback (sync_callback) to buflib so that other
sorts of synchonization are possible, such as briefly locking-out the
PCM callback for a buffer move. It's sort of a messy addition but it
is needed so voice decoding won't have to be stopped when its buffer
is moved.

Change-Id: I4d4d8c35eed5dd15fb7ee7df9323af3d036e92b3

1 files changed, 16 insertions, 12 deletions

diff --git a/firmware/buflib.c b/firmware/buflib.c
index 2d4b4b8bb2..f73c8ce4fb 100644
--- a/firmware/buflib.c
+++ b/firmware/buflib.c
@@ -210,23 +210,27 @@ move_block(struct buflib_context* ctx, union buflib_data* block, int shift)
     /* disable IRQs to make accessing the buffer from interrupt context safe. */
     /* protect the move callback, as a cached global pointer might be updated
      * in it. and protect "tmp->alloc = new_start" for buflib_get_data() */
-    disable_irq();
     /* call the callback before moving */
-    if (ops)
+    if (ops && ops->sync_callback)
+        ops->sync_callback(handle, true);
+    else
+        disable_irq();
+
+    bool retval = false;
+    if (!ops || ops->move_callback(handle, tmp->alloc, new_start)
+                    != BUFLIB_CB_CANNOT_MOVE)
     {
-        if (ops->move_callback(handle, tmp->alloc, new_start)
-                == BUFLIB_CB_CANNOT_MOVE)
-        {
-            enable_irq();
-            return false;
-        }
+        tmp->alloc = new_start; /* update handle table */
+        memmove(new_block, block, block->val * sizeof(union buflib_data));
+        retval = true;
     }
 
-    tmp->alloc = new_start; /* update handle table */
-    memmove(new_block, block, block->val * sizeof(union buflib_data));
+    if (ops && ops->sync_callback)
+        ops->sync_callback(handle, false);
+    else
+        enable_irq();
 
-    enable_irq();
-    return true;
+    return retval;
 }
 
 /* Compact allocations and handle table, adjusting handle pointers as needed.