From c942171a9955c9f2c9ee6362c492a06fe6e37e53 Mon Sep 17 00:00:00 2001
From: Dave Wu <dave.wu@analog.com>
Date: Tue, 3 Oct 2017 14:21:37 +1100
Subject: [PATCH] - Fixed an issue where the TRNG device is read even when it
 is not ready; - Added a configuration call in trng_init to make sure the TRNG
 buffering mode is disabled, so only 8-bit bytes are returned; - Moved the
 TRNG device handle into the trng_t structure; - Fixed some formatting errors
 in the adc driver.

---
 .../TARGET_ADUCM4050/api/analogin_api.c       |  6 +--
 .../TARGET_ADUCM4050/api/objects.h            |  4 +-
 .../TARGET_ADUCM4050/api/trng_api.c           | 42 ++++++++++++-------
 3 files changed, 33 insertions(+), 19 deletions(-)

diff --git a/targets/TARGET_Analog_Devices/TARGET_ADUCM4X50/TARGET_ADUCM4050/api/analogin_api.c b/targets/TARGET_Analog_Devices/TARGET_ADUCM4X50/TARGET_ADUCM4050/api/analogin_api.c
index b9ef021c19..06413a81d6 100755
--- a/targets/TARGET_Analog_Devices/TARGET_ADUCM4X50/TARGET_ADUCM4050/api/analogin_api.c
+++ b/targets/TARGET_Analog_Devices/TARGET_ADUCM4X50/TARGET_ADUCM4050/api/analogin_api.c
@@ -99,7 +99,7 @@ void analogin_init(analogin_t *obj, PinName pin)
     obj->hDevice = hDevice;
 
     /* Power up ADC */
-    adi_adc_PowerUp (hDevice, true);
+    adi_adc_PowerUp(hDevice, true);
 
     /* Set ADC reference */
     adi_adc_SetVrefSource(hDevice, ADI_ADC_VREF_SRC_INT_2_50_V);
@@ -113,7 +113,7 @@ void analogin_init(analogin_t *obj, PinName pin)
     }
 
     /* Start calibration */
-    adi_adc_StartCalibration (hDevice);
+    adi_adc_StartCalibration(hDevice);
 
     /* Wait until calibration is done */
     while (!bCalibrationDone) {
@@ -198,7 +198,7 @@ static uint32_t adi_pin2channel(PinName pin)
             break;
     }
 
-    return((uint32_t) activech);
+    return ((uint32_t)activech);
 }
 
 
diff --git a/targets/TARGET_Analog_Devices/TARGET_ADUCM4X50/TARGET_ADUCM4050/api/objects.h b/targets/TARGET_Analog_Devices/TARGET_ADUCM4X50/TARGET_ADUCM4050/api/objects.h
index 7b316f5c32..aeecf36d00 100755
--- a/targets/TARGET_Analog_Devices/TARGET_ADUCM4X50/TARGET_ADUCM4050/api/objects.h
+++ b/targets/TARGET_Analog_Devices/TARGET_ADUCM4X50/TARGET_ADUCM4050/api/objects.h
@@ -44,8 +44,8 @@
 #include "cmsis.h"
 #include "PeripheralNames.h"
 #include "PinNames.h"
-//#include "target_config.h"
 #include "gpio_object.h"
+#include "adi_rng.h"
 
 #include "adi_i2c.h"
 #include "adi_spi.h"
@@ -69,7 +69,7 @@ struct serial_s {
 };
 
 struct trng_s {
-    uint8_t dummy;
+    ADI_RNG_HANDLE  RNGhDevice;
 };
 
 #define BUILD_I2C_MI_DYNAMIC
diff --git a/targets/TARGET_Analog_Devices/TARGET_ADUCM4X50/TARGET_ADUCM4050/api/trng_api.c b/targets/TARGET_Analog_Devices/TARGET_ADUCM4X50/TARGET_ADUCM4050/api/trng_api.c
index 4012775454..8106f44e59 100755
--- a/targets/TARGET_Analog_Devices/TARGET_ADUCM4X50/TARGET_ADUCM4050/api/trng_api.c
+++ b/targets/TARGET_Analog_Devices/TARGET_ADUCM4X50/TARGET_ADUCM4050/api/trng_api.c
@@ -52,44 +52,58 @@
 #define TRNG_CNT_VAL	4095
 #define TRNG_PRESCALER 	2
 
-static ADI_RNG_HANDLE     RNGhDevice;                     /* Memory to handle CRC Device */
-static uint32_t           RngDevMem[(ADI_RNG_MEMORY_SIZE + 3)/4]; /* Data buffers for Random numbers */
+/* Data buffers for Random numbers */
+static uint32_t RngDevMem[(ADI_RNG_MEMORY_SIZE + 3)/4];
 
 void trng_init(trng_t *obj)
 {
-    (void)obj;
+	ADI_RNG_HANDLE RNGhDevice;
+
+	// Open the device
     adi_rng_Open(0,RngDevMem,sizeof(RngDevMem),&RNGhDevice);
 
     // Set sample length for the H/W RN accumulator
     adi_rng_SetSampleLen(RNGhDevice, TRNG_PRESCALER, TRNG_CNT_VAL);
 
-    // Enable the RNG
+	// Disable buffering - single byte generation only
+	adi_rng_EnableBuffering(RNGhDevice, false);
+
+	// Enable the TRNG
     adi_rng_Enable(RNGhDevice, true);
+
+	// Save device handle
+	obj->RNGhDevice = RNGhDevice;
 }
 
 void trng_free(trng_t *obj)
 {
-    (void)obj;
+    ADI_RNG_HANDLE RNGhDevice = obj->RNGhDevice;
+
     adi_rng_Enable(RNGhDevice, false);
     adi_rng_Close(RNGhDevice);
 }
 
 int trng_get_bytes(trng_t *obj, uint8_t *output, size_t length, size_t *output_length)
 {
-    (void)obj;
+    ADI_RNG_HANDLE RNGhDevice = obj->RNGhDevice;
     bool bRNGRdy;
     uint32_t nRandomNum, i;
 
-    for (i = 0; i < length; ) {
-        // wait for the RNG ready to give a random number
-        adi_rng_GetRdyStatus(RNGhDevice, &bRNGRdy);
-        if (bRNGRdy) {
-            // read the random number
-            adi_rng_GetRngData(RNGhDevice, &nRandomNum);
-            output[i++] = (uint8_t) nRandomNum;
-        }
+    for (i = 0; i < length; i++) {
+        // Loop until the device has data to be read
+        do {
+            adi_rng_GetRdyStatus(RNGhDevice, &bRNGRdy);
+        } while (!bRNGRdy);
+
+        // Read the RNG
+        adi_rng_GetRngData(RNGhDevice, &nRandomNum);
+
+        // Save the output
+		output[i] = (uint8_t)nRandomNum;
     }
+
     *output_length = length;
+
     return 0;
 }