Initial changes to allow for xvsm demo

module_usb_audio/audio_io/userbuffermanagement.c

@@ -0,0 +1,9 @@
+
+#include "xccompat.h"
+
+/* Default implentation for UserBufferManagement() */
+void UserBufferManagement(unsigned sampsFromUsbToAudio[], unsigned sampsFromAudioToUsb[], unsigned i_dsp) __attribute__ ((weak));
+void UserBufferManagement(unsigned sampsFromUsbToAudio[], unsigned sampsFromAudioToUsb[], unsigned i_dsp)
+{
+    /* Do nothing */
+}

module_usb_audio/audio_io/xua_audio.h

@@ -0,0 +1,39 @@
+#ifndef __audio_h__
+#define __audio_h__
+
+#include "devicedefines.h"
+#include "dfu_interface.h"
+#include "dsp.h"
+
+/** The audio driver thread.
+ *
+ *  This function drives I2S ports and handles samples to/from other digital
+ *  I/O threads.
+ *
+ *  \param c_in Audio sample channel connected to the mixer() thread or the
+ *              decouple() thread
+ *  \param c_dig channel connected to the clockGen() thread for
+ *               receiving/transmitting samples
+ *  \param c_config An optional channel that will be passed on to the
+ *                  CODEC configuration functions.
+ */
+void audio(chanend c_in,
+#if defined(SPDIF_TX) && (SPDIF_TX_TILE != AUDIO_IO_TILE)
+    chanend c_spdif_tx,
+#endif
+#if(defined(SPDIF_RX) || defined(ADAT_RX))
+    chanend c_dig,
+#endif
+    chanend ?c_config, chanend ?c_adc
+#if (XUD_TILE != 0)
+   , server interface i_dfu dfuInterface
+#endif
+#if (NUM_PDM_MICS > 0)
+    , chanend c_pdm_in
+#endif
+    , client dsp_if i_dsp
+);
+
+void SpdifTxWrapper(chanend c_spdif_tx);
+
+#endif // __audio_h__