HR_Cx000: driver refactoring

- removed the Cx000_uSpiBusy() function.
- HR_Cx000 class is no more singleton.
- added constructor parameters for USPI interface.

platform/drivers/baseband/HR_C5000.h

@@ -1,5 +1,5 @@
 /***************************************************************************
- *   Copyright (C) 2021 - 2023 by Federico Amedeo Izzo IU2NUO,             *
+ *   Copyright (C) 2021 - 2024 by Federico Amedeo Izzo IU2NUO,             *
  *                                Niccolò Izzo IU2KIN                      *
  *                                Frederik Saraci IU2NRO                   *
  *                                Silvano Seva IU2KWO                      *

platform/drivers/baseband/HR_C5000_MDx.cpp

@@ -1,5 +1,5 @@
 /***************************************************************************
- *   Copyright (C) 2020 - 2023 by Federico Amedeo Izzo IU2NUO,             *
+ *   Copyright (C) 2020 - 2024 by Federico Amedeo Izzo IU2NUO,             *
  *                                Niccolò Izzo IU2KIN                      *
  *                                Frederik Saraci IU2NRO                   *
  *                                Silvano Seva IU2KWO                      *
@@ -63,10 +63,6 @@ template< class M >
 void HR_Cx000< M >::terminate()
 {
     gpio_setPin(DMR_SLEEP);
-    gpio_setMode(DMR_CS,    INPUT);
-    gpio_setMode(DMR_CLK,   INPUT);
-    gpio_setMode(DMR_MOSI,  INPUT);
-    gpio_setMode(DMR_MISO,  INPUT);
     gpio_setMode(DMR_SLEEP, INPUT);
 }
 
@@ -186,47 +182,3 @@ void HR_Cx000< M >::stopAnalogTx()
 {
     writeReg(M::CONFIG, 0x60, 0x00);    // Disable both analog and DMR transmission
 }
-
-/*
- * SPI interface driver
- */
-template< class M >
-void HR_Cx000< M >::uSpi_init()
-{
-    gpio_setMode(DMR_CS,    OUTPUT);
-    gpio_setMode(DMR_CLK,   OUTPUT);
-    gpio_setMode(DMR_MOSI,  OUTPUT);
-    gpio_setMode(DMR_MISO,  OUTPUT);
-
-    // Deselect HR_C5000, idle state of the CS line.
-    gpio_setPin(DMR_CS);
-}
-
-template< class M >
-uint8_t HR_Cx000< M >::uSpi_sendRecv(const uint8_t value)
-{
-    gpio_clearPin(DMR_CLK);
-
-    uint8_t incoming = 0;
-
-    for(uint8_t cnt = 0; cnt < 8; cnt++)
-    {
-        gpio_setPin(DMR_CLK);
-
-        if(value & (0x80 >> cnt))
-        {
-            gpio_setPin(DMR_MOSI);
-        }
-        else
-        {
-            gpio_clearPin(DMR_MOSI);
-        }
-
-        delayUs(1);
-        gpio_clearPin(DMR_CLK);
-        incoming = (incoming << 1) | gpio_readPin(DMR_MISO);
-        delayUs(1);
-    }
-
-    return incoming;
-}

platform/drivers/baseband/HR_C6000.h

@@ -1,5 +1,5 @@
 /***************************************************************************
- *   Copyright (C) 2021 - 2023 by Federico Amedeo Izzo IU2NUO,             *
+ *   Copyright (C) 2021 - 2024 by Federico Amedeo Izzo IU2NUO,             *
  *                                Niccolò Izzo IU2KIN                      *
  *                                Frederik Saraci IU2NRO                   *
  *                                Silvano Seva IU2KWO                      *

platform/drivers/baseband/HR_C6000_GDx.cpp

@@ -140,7 +140,6 @@ template< class M >
 void HR_Cx000< M >::terminate()
 {
     gpio_setPin(DMR_SLEEP);
-    gpio_setMode(DMR_CS, INPUT);
 }
 
 template< class M >

platform/drivers/baseband/HR_C6000_UV3x0.cpp

@@ -52,9 +52,7 @@ template class HR_Cx000 < C6000_SpiOpModes >;
 template< class M >
 void HR_Cx000< M >::init()
 {
-    gpio_setMode(DMR_CS,    OUTPUT);
     gpio_setMode(DMR_SLEEP, OUTPUT);
-
     gpio_setPin(DMR_SLEEP);
 
     delayMs(10);
@@ -117,7 +115,6 @@ template< class M >
 void HR_Cx000< M >::terminate()
 {
     gpio_setPin(DMR_SLEEP);
-    gpio_setMode(DMR_CS, INPUT);
 }
 
 template< class M >
@@ -226,47 +223,3 @@ void HR_Cx000< M >::stopAnalogTx()
     writeReg(M::CONFIG, 0x34, 0x98);    // FM bpf enabled, 25kHz bandwidth
     writeReg(M::CONFIG, 0x26, 0xFD);    // Undocumented register, enable FM receive
 }
-
-/*
- * SPI interface driver
- */
-template< class M >
-void HR_Cx000< M >::uSpi_init()
-{
-    gpio_setMode(DMR_CS,    OUTPUT);
-    gpio_setMode(DMR_CLK,   OUTPUT);
-    gpio_setMode(DMR_MOSI,  OUTPUT);
-    gpio_setMode(DMR_MISO,  OUTPUT);
-
-    // Deselect HR_C6000, idle state of the CS line.
-    gpio_setPin(DMR_CS);
-}
-
-template< class M >
-uint8_t HR_Cx000< M >::uSpi_sendRecv(const uint8_t value)
-{
-    gpio_clearPin(DMR_CLK);
-
-    uint8_t incoming = 0;
-
-    for(uint8_t cnt = 0; cnt < 8; cnt++)
-    {
-        gpio_setPin(DMR_CLK);
-
-        if(value & (0x80 >> cnt))
-        {
-            gpio_setPin(DMR_MOSI);
-        }
-        else
-        {
-            gpio_clearPin(DMR_MOSI);
-        }
-
-        delayUs(1);
-        gpio_clearPin(DMR_CLK);
-        incoming = (incoming << 1) | gpio_readPin(DMR_MISO);
-        delayUs(1);
-    }
-
-    return incoming;
-}

platform/drivers/baseband/HR_Cx000.cpp

@@ -1,5 +1,5 @@
 /***************************************************************************
- *   Copyright (C) 2021 - 2023 by Federico Amedeo Izzo IU2NUO,             *
+ *   Copyright (C) 2021 - 2024 by Federico Amedeo Izzo IU2NUO,             *
  *                                Niccolò Izzo IU2KIN                      *
  *                                Frederik Saraci IU2NRO                   *
  *                                Silvano Seva IU2KWO                      *
@@ -26,11 +26,6 @@
 #include "HR_C5000.h"
 #include "HR_C6000.h"
 
-bool Cx000_uSpiBusy()
-{
-    return (gpio_readPin(DMR_CS) == 0) ? true : false;
-}
-
 template <>
 void HR_Cx000< C5000_SpiOpModes >::setDacGain(int8_t gain)
 {
@@ -120,16 +115,22 @@ void HR_Cx000< C6000_SpiOpModes >::setInputGain(int8_t value)
     writeReg(C6000_SpiOpModes::CONFIG, 0xE4, regValue);
 }
 
-ScopedChipSelect::ScopedChipSelect()
+ScopedChipSelect::ScopedChipSelect(const struct spiDevice *spi,
+                                   const struct gpioPin& cs) : spi(spi), cs(cs)
 {
-    gpio_clearPin(DMR_CS);
+    spi_acquire(spi);
+    gpioPin_clear(&cs);
 }
 
 ScopedChipSelect::~ScopedChipSelect()
 {
+    // NOTE: it seems that, without the 2us delays before and after the nCS
+    // deassertion, the HR_C6000 doesn't work properly. At least this is what
+    // has been observed on the Retevis RT3s.
     delayUs(2);
-    gpio_setPin(DMR_CS);
+    gpioPin_set(&cs);
     delayUs(2);
+    spi_release(spi);
 }
 
 FmConfig operator |(FmConfig lhs, FmConfig rhs)

platform/drivers/baseband/HR_Cx000.h

@@ -1,5 +1,5 @@
 /***************************************************************************
- *   Copyright (C) 2021 - 2023 by Federico Amedeo Izzo IU2NUO,             *
+ *   Copyright (C) 2021 - 2024 by Federico Amedeo Izzo IU2NUO,             *
  *                                Niccolò Izzo IU2KIN                      *
  *                                Frederik Saraci IU2NRO                   *
  *                                Silvano Seva IU2KWO                      *
@@ -21,29 +21,12 @@
 #ifndef HRCx000_H
 #define HRCx000_H
 
+#include <peripherals/gpio.h>
+#include <peripherals/spi.h>
 #include <stdbool.h>
 #include <stdint.h>
 #include <stddef.h>
 
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/**
- * Check if "user" SPI bus, on some platforms shared between the baseband and
- * other chips, is in use by the HR_Cx000 driver. This function is callable
- * either from C or C++ sources.
- *
- * WARNING: this function is NOT thread safe! A proper critical section has to
- * be set up to ensure it is accessed by one task at a time.
- *
- * @return true if SPI lines are being used by this driver.
- */
-bool Cx000_uSpiBusy();
-
-#ifdef __cplusplus
-}
-
 /**
  * Configuration options for analog FM mode.
  * Each option is tied to a particular bit of the Configuration register 0x34.
@@ -66,32 +49,26 @@ enum class TxAudioSource
     LINE_IN     ///< Audio source is "line in", e.g. tone generator.
 };
 
-/**
- * Generic driver for HR_C5000/HR_C6000 "baseband" chip.
- *
- *
- * WARNING: on some MDx devices the PLL and DMR chips share the SPI MOSI line,
- * thus particular care has to be put to avoid them stomping reciprocally.
- * This driver does not make any check if a SPI transfer is already in progress,
- * deferring the correct bus management to higher level modules. However,
- * a function returning true if the bus is currently in use by this driver is
- * provided.
- */
-
 class ScopedChipSelect;
 
+/**
+ * Generic driver for HR_C5000/HR_C6000 "baseband" chip.
+ */
 template< class M >
 class HR_Cx000
 {
 public:
 
     /**
-     * \return a reference to the instance of the AT1846S class (singleton).
+     * Constructor.
+     *
+     * @param dev: pointer to chip's hardware interface descriptor.
      */
-    static HR_Cx000& instance()
+    HR_Cx000(const struct spiDevice *uSpi, const struct gpioPin uCs) : uSpi(uSpi), uCs(uCs)
     {
-        static HR_Cx000< M > Cx000;
+        // Configure chip select pin
-        return Cx000;
+        gpioPin_setMode(&uCs, OUTPUT);
+        gpioPin_set(&uCs);
     }
 
     /**
@@ -101,6 +78,7 @@ public:
     ~HR_Cx000()
     {
         terminate();
+        gpioPin_setMode(&uCs, INPUT);
     }
 
     /**
@@ -212,15 +190,6 @@ public:
 
 private:
 
-    /**
-     * Constructor.
-     */
-    HR_Cx000()
-    {
-        // Being a singleton class, uSPI is initialised only once.
-        uSpi_init();
-    }
-
     /**
      * Helper function for register writing.
      *
@@ -230,10 +199,14 @@ private:
      */
     void writeReg(const M opMode, const uint8_t addr, const uint8_t value)
     {
-        ScopedChipSelect cs;
+        uint8_t data[3];
-        (void) uSpi_sendRecv(static_cast< uint8_t >(opMode));
+
-        (void) uSpi_sendRecv(addr);
+        data[0] = static_cast< uint8_t >(opMode);
-        (void) uSpi_sendRecv(value);
+        data[1] = addr;
+        data[2] = value;
+
+        ScopedChipSelect cs(uSpi, uCs);
+        spi_send(uSpi, data, 3);
     }
 
     /**
@@ -245,10 +218,17 @@ private:
      */
     uint8_t readReg(const M opMode, const uint8_t addr)
     {
-        ScopedChipSelect cs;
+        uint8_t cmd[3];
-        (void) uSpi_sendRecv(static_cast< uint8_t >(opMode) | 0x80);
+        uint8_t ret[3];
-        (void) uSpi_sendRecv(addr);
+
-        return uSpi_sendRecv(0x00);
+        cmd[0] = 0x80 | static_cast< uint8_t >(opMode);
+        cmd[1] = addr;
+        cmd[2] = 0x00;
+
+        ScopedChipSelect cs(uSpi, uCs);
+        spi_transfer(uSpi, cmd, ret, 3);
+
+        return ret[2];
     }
 
     /**
@@ -260,26 +240,12 @@ private:
      */
     void sendSequence(const uint8_t *seq, const size_t len)
     {
-        ScopedChipSelect cs;
+        ScopedChipSelect cs(uSpi, uCs);
-        for(size_t i = 0; i < len; i++)
+        spi_send(uSpi, seq, len);
-        {
-            (void) uSpi_sendRecv(seq[i]);
-        }
     }
 
-    /**
+    const struct spiDevice *uSpi;
-     * Initialise the low-level driver which manages "user" SPI interface, that
+    const struct gpioPin uCs;
-     * is the one used to configure the chipset functionalities.
-     */
-    void uSpi_init();
-
-    /**
-     * Transfer one byte across the "user" SPI interface.
-     *
-     * @param value: value to be sent.
-     * @return incoming byte from the baseband chip.
-     */
-    uint8_t uSpi_sendRecv(const uint8_t value);
 };
 
 /**
@@ -299,19 +265,23 @@ public:
 
     /**
      * Constructor.
-     * When called it brings the  HR_C5000/HR_C6000 chip select to logical low,
+     * When called it acquires exclusive ownership on the "user" SPI bus and
-     * selecting it.
+     * brings the  HR_C5000/HR_C6000 chip select to logical low.
+     *
+     * @param dev: pointer to device interface.
      */
-    ScopedChipSelect();
+    ScopedChipSelect(const struct spiDevice *spi, const struct gpioPin& cs);
 
     /**
      * Destructor.
      * When called it brings the  HR_C5000/HR_C6000 chip select to logical high,
-     * deselecting it.
+     * and releases exclusive ownership on the "user" SPI bus.
      */
     ~ScopedChipSelect();
+
+private:
+    const struct spiDevice *spi;
+    const struct gpioPin& cs;
 };
 
-#endif // __cplusplus
-
 #endif // HRCx000_H