From 6c5253abb00a032cba824f18d424ee233a36a468 Mon Sep 17 00:00:00 2001
From: Ross Owen <ross@xmos.com>
Date: Wed, 16 Oct 2013 19:09:21 +0100
Subject: [PATCH] A more elegant solution to the DSD stop_clock() pausing
 issue. Just set ALL clocks to 0 before deliver returns

---
 module_usb_audio/audio.xc            |  5 ++++-
 module_usb_audio/ports/audioports.xc | 16 ++++++----------
 2 files changed, 10 insertions(+), 11 deletions(-)

diff --git a/module_usb_audio/audio.xc b/module_usb_audio/audio.xc
index a97da327..1f3ca087 100755
--- a/module_usb_audio/audio.xc
+++ b/module_usb_audio/audio.xc
@@ -325,7 +325,6 @@ extern void device_reboot(void);
             p_bclk <: 0;
 #if(DSD_CHANS_DAC != 0) 
             /* DSD Clock might not be shared with lrclk or bclk... */
-            if(dsdMode)
             p_dsd_clk <: 0;
 #endif
             command = inct(c_out);
@@ -714,6 +713,7 @@ extern void device_reboot(void);
                     // Set clocks low
                     p_lrclk <: 0;
                     p_bclk <: 0;
+                    p_dsd_clk <: 0;
                     return {0,0};
                 }
             }
@@ -731,6 +731,9 @@ extern void device_reboot(void);
                 if((DSD_MASK(samplesOut[0]) != DSD_MARKER_2) && (DSD_MASK(samplesOut[1]) != DSD_MARKER_2))
                 {
                     dsdMode = 0;
+                    // Set clocks low
+                    p_lrclk <: 0;
+                    p_bclk <: 0;
                     p_dsd_clk <: 0;
                     return {0,0};
                 }
diff --git a/module_usb_audio/ports/audioports.xc b/module_usb_audio/ports/audioports.xc
index 515deaca..ce6d4679 100644
--- a/module_usb_audio/ports/audioports.xc
+++ b/module_usb_audio/ports/audioports.xc
@@ -32,16 +32,7 @@ unsigned int divide)
 {
 
 #ifndef CODEC_MASTER
-    /* Output 0 on BCLK to ensure clock is low
-     * Required as stop_clock will only complete when the clock is low
-     */
- //   configure_out_port_no_ready(p_bclk, clk_audio_mclk, 0);
-  //  p_bclk <: 0;
-    
-    /* Stop_clock() will not complete if the source to the clock-block is not low
-     * since we are switching between DSD and I2S we grab the source from the clock
-     * -block and set it low
-     */
+#if 0
     {
         unsigned clockResId;
         unsigned portResId;
@@ -50,6 +41,11 @@ unsigned int divide)
         if(portResId !=1)
             asm("out res[%0], %1":: "r"(portResId), "r"(0));
     }
+#endif
+
+    /* Note this call to stop_clock() will pause forever if the port clocking the clock-block is not low.
+     * deliver() should return with this being the case - however, if you are having trouble the code 
+     * above can be enabled */
     stop_clock(clk_audio_bclk);
 
     if(!isnull(p_lrclk))