From 8f9502cade97224c626bcd2d18aac94e2ca33091 Mon Sep 17 00:00:00 2001
From: Silvano Seva <silseva@fastwebnet.it>
Date: Sun, 29 Sep 2024 17:17:16 +0200
Subject: [PATCH] MDUV3x0: updated radio driver

---
 openrtx/src/rtx/OpMode_FM.cpp             |  6 +--
 platform/drivers/baseband/radio_UV3x0.cpp |  7 +++-
 platform/targets/MD-UV3x0/hwconfig.c      | 47 +++++++++++++++++++++++
 platform/targets/MD-UV3x0/hwconfig.h      |  7 ++++
 platform/targets/MD-UV3x0/pinmap.h        |  2 +-
 5 files changed, 63 insertions(+), 6 deletions(-)

diff --git a/openrtx/src/rtx/OpMode_FM.cpp b/openrtx/src/rtx/OpMode_FM.cpp
index d4b19638..0eec9244 100644
--- a/openrtx/src/rtx/OpMode_FM.cpp
+++ b/openrtx/src/rtx/OpMode_FM.cpp
@@ -24,9 +24,7 @@
 #include <OpMode_FM.hpp>
 #include <rtx.h>
 
-#if defined(PLATFORM_MDUV3x0)
-#include "../../../drivers/baseband/HR_C6000.h"
-#elif defined(PLATFORM_TTWRPLUS)
+#if defined(PLATFORM_TTWRPLUS)
 #include "AT1846S.h"
 #endif
 
@@ -50,7 +48,7 @@ void _setVolume()
 #if defined(PLATFORM_MDUV3x0)
     // Apply new volume level, map 0 - 255 range into -31 to 31
     int8_t gain = ((int8_t) (volume / 4)) - 31;
-    HR_C6000::instance().setDacGain(gain);
+    C6000.setDacGain(gain);
 #elif defined(PLATFORM_TTWRPLUS)
     // AT1846S volume control is 4 bit
     AT1846S::instance().setRxAudioGain(volume / 16, volume / 16);
diff --git a/platform/drivers/baseband/radio_UV3x0.cpp b/platform/drivers/baseband/radio_UV3x0.cpp
index 3de4aaa3..9ea77403 100644
--- a/platform/drivers/baseband/radio_UV3x0.cpp
+++ b/platform/drivers/baseband/radio_UV3x0.cpp
@@ -43,7 +43,7 @@ static uint8_t txModBias  = 0;                   // VCXO bias for TX
 
 static enum opstatus radioStatus;                // Current operating status
 
-static HR_C6000& C6000  = HR_C6000::instance();  // HR_C5000 driver
+HR_C6000 C6000((const struct spiDevice *) &c6000_spi, { DMR_CS }); // HR_C6000 driver
 static AT1846S& at1846s = AT1846S::instance();   // AT1846S driver
 
 void radio_init(const rtxStatus_t *rtxState)
@@ -87,6 +87,11 @@ void radio_init(const rtxStatus_t *rtxState)
     /*
      * Configure AT1846S and HR_C6000, keep AF output disabled at power on.
      */
+    gpio_setMode(DMR_CLK,  OUTPUT);
+    gpio_setMode(DMR_MOSI, OUTPUT);
+    gpio_setMode(DMR_MISO, INPUT);
+    spi_init((const struct spiDevice *) &c6000_spi);
+
     at1846s.init();
     C6000.init();
     radio_disableAfOutput();
diff --git a/platform/targets/MD-UV3x0/hwconfig.c b/platform/targets/MD-UV3x0/hwconfig.c
index d956b831..c916d01e 100644
--- a/platform/targets/MD-UV3x0/hwconfig.c
+++ b/platform/targets/MD-UV3x0/hwconfig.c
@@ -18,7 +18,54 @@
  *   along with this program; if not, see <http://www.gnu.org/licenses/>   *
  ***************************************************************************/
 
+#include <spi_bitbang.h>
+#include <spi_custom.h>
 #include <hwconfig.h>
+#include <pinmap.h>
 #include <spi_stm32.h>
 
+/**
+ * SPI bitbang function for HR_C6000 command interface (U_SPI).
+ *
+ * Hand-tuned to be as fast as possible, gives the following clock performance
+ * when compiled with -Os and run on STM32F405 at 168MHz:
+ *
+ * - Freq 6.46MHz
+ * - Pos. width 71ns
+ * - Neg. with 83ns
+ */
+static uint8_t spiC6000_func(const void *priv, uint8_t value)
+{
+    (void) priv;
+    uint8_t incoming = 0;
+
+    __disable_irq();
+
+    for(uint8_t cnt = 0; cnt < 8; cnt++)
+    {
+        GPIOE->BSRR = (1 << 3);     // Set PE3 (CLK)
+
+        if(value & (0x80 >> cnt))
+            GPIOE->BSRR = 1 << 4;   // Set PE4 (MOSI)
+        else
+            GPIOE->BSRR = 1 << 20;  // Clear PE4 (MOSI)
+
+        // ~70ns delay
+        asm volatile("           mov   r1, #1     \n"
+                     "___loop_1: cmp   r1, #0     \n"
+                     "           itt   ne         \n"
+                     "           subne r1, r1, #1 \n"
+                     "           bne   ___loop_1  \n":::"r1");
+
+        incoming <<= 1;
+        GPIOE->BSRR = (1 << 19);                // Clear PE3 (CLK)
+        incoming |= (GPIOE->IDR >> 5) & 0x01;   // Read PE5 (MISO)
+    }
+
+    __enable_irq();
+
+    return incoming;
+}
+
+SPI_CUSTOM_DEVICE_DEFINE(c6000_spi, spiC6000_func, NULL, NULL)
 SPI_STM32_DEVICE_DEFINE(nvm_spi, SPI1, NULL)
diff --git a/platform/targets/MD-UV3x0/hwconfig.h b/platform/targets/MD-UV3x0/hwconfig.h
index a3f7a707..d016fa57 100644
--- a/platform/targets/MD-UV3x0/hwconfig.h
+++ b/platform/targets/MD-UV3x0/hwconfig.h
@@ -24,9 +24,16 @@
 #include "pinmap.h"
 
 #ifdef __cplusplus
+
+// Export the HR_C6000 driver only for C++ sources
+#include <HR_C6000.h>
+
+extern HR_C6000 C6000;
+
 extern "C" {
 #endif
 
+extern const struct spiCustomDevice c6000_spi;
 extern const struct spiDevice nvm_spi;
 
 /* Device has a working real time clock */
diff --git a/platform/targets/MD-UV3x0/pinmap.h b/platform/targets/MD-UV3x0/pinmap.h
index 7be31347..7940b8b8 100644
--- a/platform/targets/MD-UV3x0/pinmap.h
+++ b/platform/targets/MD-UV3x0/pinmap.h
@@ -108,7 +108,7 @@
 
 /* HR_C6000 control interface */
 #define DMR_SLEEP GPIOE,6
-#define DMR_CS    GPIOE,2
+#define DMR_CS    &GpioE,2
 #define DMR_CLK   GPIOE,3
 #define DMR_MOSI  GPIOE,4
 #define DMR_MISO  GPIOE,5