From 0ed22a04170f3b17dc5d471b6f5a2fb68ed71f4f Mon Sep 17 00:00:00 2001
From: Ross Owen <ross@xmos.com>
Date: Wed, 16 Mar 2016 15:21:17 +0000
Subject: [PATCH] Audio port config functions now get passed SR. Simple clock
 delay (falling edge) added for xCORE-slave mode when bclk >= 20MHz

---
 module_usb_audio/audio.xc            |  4 ++--
 module_usb_audio/ports/audioports.c  |  4 ++--
 module_usb_audio/ports/audioports.h  |  8 ++++----
 module_usb_audio/ports/audioports.xc | 14 +++++++++++++-
 4 files changed, 21 insertions(+), 9 deletions(-)

diff --git a/module_usb_audio/audio.xc b/module_usb_audio/audio.xc
index de905b83..47a8cdab 100755
--- a/module_usb_audio/audio.xc
+++ b/module_usb_audio/audio.xc
@@ -1098,7 +1098,7 @@ chanend ?c_config, chanend ?c
                 null,
                 p_dsd_clk,
 #endif
-                divide, dsdMode);
+                divide, curSamFreq, dsdMode);
         }
         else
 #endif
@@ -1122,7 +1122,7 @@ chanend ?c_config, chanend ?c
                 p_bclk,
 #endif
 #endif
-            divide, dsdMode);
+            divide, curSamFreq, dsdMode);
 }
 
 
diff --git a/module_usb_audio/ports/audioports.c b/module_usb_audio/ports/audioports.c
index d5e72b03..ddd1fd3e 100644
--- a/module_usb_audio/ports/audioports.c
+++ b/module_usb_audio/ports/audioports.c
@@ -43,7 +43,7 @@ void ConfigAudioPortsWrapper(
                 port p_lrclk,
                 port p_bclk,
 #endif
-unsigned int divide, unsigned int dsdMode)
+unsigned int divide, unsigned curSamFreq, unsigned int dsdMode)
 {
         ConfigAudioPorts(
 #if (I2S_CHANS_DAC != 0) || (DSD_CHANS_DAC != 0)
@@ -56,5 +56,5 @@ unsigned int divide, unsigned int dsdMode)
 #endif
                 p_lrclk,
                 p_bclk,
-                divide);
+                divide, curSamFreq);
 }
diff --git a/module_usb_audio/ports/audioports.h b/module_usb_audio/ports/audioports.h
index 153b28e5..fb44d455 100644
--- a/module_usb_audio/ports/audioports.h
+++ b/module_usb_audio/ports/audioports.h
@@ -26,7 +26,7 @@ void ConfigAudioPorts(
                 in port p_bclk,
 #endif
 #endif
-                unsigned int divide);
+                unsigned int divide, unsigned int curSamFreq);
 #else
 
 void ConfigAudioPorts(
@@ -49,7 +49,7 @@ void ConfigAudioPorts(
                 port p_bclk,
 #endif
 #endif
-                unsigned int divide);
+                unsigned int divide, unsigned int curSamFreq);
 
 
 #endif /* __XC__*/
@@ -74,7 +74,7 @@ void ConfigAudioPortsWrapper(
                 in port p_bclk,
 #endif
 #endif
-                unsigned int divide, unsigned int dsdMode);
+                unsigned int divide, unsigned curSamFreq, unsigned int dsdMode);
 #else
 
 void ConfigAudioPortsWrapper(
@@ -90,7 +90,7 @@ void ConfigAudioPortsWrapper(
                 port p_lrclk,
                 port p_bclk,
 #endif
-                unsigned int divide, unsigned int dsdMode);
+                unsigned int divide, unsigned curSamFreq, unsigned int dsdMode);
 
 
 #endif /* __XC__*/
diff --git a/module_usb_audio/ports/audioports.xc b/module_usb_audio/ports/audioports.xc
index 20188e07..3786ae8b 100644
--- a/module_usb_audio/ports/audioports.xc
+++ b/module_usb_audio/ports/audioports.xc
@@ -28,7 +28,7 @@ void ConfigAudioPorts(
         in port p_bclk,
 #endif
 #endif
-unsigned int divide)
+unsigned int divide, unsigned curSamFreq)
 {
 #if !defined(CODEC_MASTER)
     /* Note this call to stop_clock() will pause forever if the port clocking the clock-block is not low.
@@ -116,6 +116,18 @@ unsigned int divide)
     /* Clock bclk clock-block from bclk pin */
     configure_clock_src(clk_audio_bclk, p_bclk);
 
+
+    /* Do some clocking shifting to get data in the valid window */
+    /* E.g. Only shift when running at 88.2+ kHz TDM slave */
+    int bClkDelay_fall = 0;
+    if(curSamFreq * I2S_CHANS_PER_FRAME * 32 >= 20000000)
+    {
+        /* 18 * 2ns = 36ns. This results in a -4ns (36 - 40) shift at 96KHz and -8ns (36 - 44) at 88.4KHz */
+        bClkDelay_fall = 18;
+    }
+
+    set_clock_fall_delay(clk_audio_bclk, bClkDelay_fall);
+
 #if (I2S_CHANS_DAC != 0)
      /* Clock I2S output data ports from b-clock clock block */
     for(int i = 0; i < I2S_WIRES_DAC; i++)