- Added mixer related defines to reduce use of magic numbers

- Increases debug output when DEBUG flag set
- Removed some dead code
- Increased alignment of asm mixer functions
- Removed some usages of “xc_ptr” type in favour of native pointers in XC
- Added some asserts to mixer
- Added test_mixer_routing_input
- Moved test_mixer_routing_output to use shared code

lib_xua/api/xua_mixer.h

@@ -3,6 +3,8 @@
 #ifndef _XUA_MIXER_H_
 #define _XUA_MIXER_H_
 
+#include "xua.h"
+
 enum mix_ctl_cmd {
   SET_SAMPLES_TO_HOST_MAP,
   SET_SAMPLES_TO_DEVICE_MAP,
@@ -31,4 +33,14 @@ enum mix_ctl_cmd {
  */
 void mixer(chanend c_to_host, chanend c_to_audio, chanend c_mix_ctl);
 
+#define XUA_MIXER_OFFSET_OUT        (0)
+#define XUA_MIXER_OFFSET_IN         (NUM_USB_CHAN_OUT)
+#define XUA_MIXER_OFFSET_MIX        (NUM_USB_CHAN_OUT + NUM_USB_CHAN_IN)
+#define XUA_MIXER_OFFSET_OFF        (NUM_USB_CHAN_OUT + NUM_USB_CHAN_IN + MAX_MIX_COUNT)
+
+/* Defines uses for DB to actual muliplier conversion */
+#define XUA_MIXER_MULT_FRAC_BITS    (25)
+#define XUA_MIXER_DB_FRAC_BITS      (8)
+#define XUA_MIXER_MAX_MULT          (1<<XUA_MIXER_MULT_FRAC_BITS) /* i.e. multiply by 0 */
+
 #endif