feat(spi): add slave mode support

Signed-off-by: patricklaf <[email protected]> Co-authored-by: Frederic Pillon <[email protected]>
stm32duino · Dec 6, 2023 · 78e0808 · 78e0808
1 parent b149a92
commit 78e0808
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Showing 5 changed files with 56 additions and 33 deletions.
diff --git a/libraries/SPI/keywords.txt b/libraries/SPI/keywords.txt
@@ -30,5 +30,8 @@ SPI_MODE1	LITERAL1
 SPI_MODE2	LITERAL1
 SPI_MODE3	LITERAL1
 
-SPI_CONTINUE	LITERAL1
-SPI_LAST	LITERAL1
+SPI_TRANSMITRECEIVE	LITERAL1
+SPI_TRANSMITONLY	LITERAL1
+SPI_MASTER	LITERAL1
+SPI_SLAVE	LITERAL1
+
diff --git a/libraries/SPI/src/SPI.cpp b/libraries/SPI/src/SPI.cpp
@@ -53,28 +53,28 @@ SPIClass::SPIClass(uint32_t mosi, uint32_t miso, uint32_t sclk, uint32_t ssel)
 
 /**
   * @brief  Initialize the SPI instance.
+  * @param  device: device mode (optional), SPI_MASTER or SPI_SLAVE. Default is master.
   */
-void SPIClass::begin(void)
+void SPIClass::begin(SPIDeviceMode device)
 {
   _spi.handle.State = HAL_SPI_STATE_RESET;
   _spiSettings = SPISettings();
-  spi_init(&_spi, _spiSettings.clockFreq,
-           _spiSettings.dataMode,
-           _spiSettings.bitOrder);
+  _spiSettings.deviceMode = device;
+  spi_init(&_spi, _spiSettings.clockFreq, _spiSettings.dataMode,
+           _spiSettings.bitOrder, _spiSettings.deviceMode);
 }
 
 /**
   * @brief  This function should be used to configure the SPI instance in case you
   *         don't use the default parameters set by the begin() function.
-  * @param  settings: SPI settings(clock speed, bit order, data mode).
+  * @param  settings: SPI settings(clock speed, bit order, data mode, device mode).
   */
 void SPIClass::beginTransaction(SPISettings settings)
 {
   if (_spiSettings != settings) {
     _spiSettings = settings;
-    spi_init(&_spi, _spiSettings.clockFreq,
-             _spiSettings.dataMode,
-             _spiSettings.bitOrder);
+    spi_init(&_spi, _spiSettings.clockFreq, _spiSettings.dataMode,
+             _spiSettings.bitOrder, _spiSettings.deviceMode);
   }
 }
 
@@ -103,9 +103,8 @@ void SPIClass::setBitOrder(BitOrder bitOrder)
 {
   _spiSettings.bitOrder = bitOrder;
 
-  spi_init(&_spi, _spiSettings.clockFreq,
-           _spiSettings.dataMode,
-           _spiSettings.bitOrder);
+  spi_init(&_spi, _spiSettings.clockFreq, _spiSettings.dataMode,
+           _spiSettings.bitOrder, _spiSettings.deviceMode);
 }
 
 /**
@@ -127,9 +126,8 @@ void SPIClass::setDataMode(uint8_t mode)
 void SPIClass::setDataMode(SPIMode mode)
 {
   _spiSettings.dataMode = mode;
-  spi_init(&_spi, _spiSettings.clockFreq,
-           _spiSettings.dataMode,
-           _spiSettings.bitOrder);
+  spi_init(&_spi, _spiSettings.clockFreq, _spiSettings.dataMode,
+           _spiSettings.bitOrder, _spiSettings.deviceMode);
 }
 
 /**
@@ -147,9 +145,8 @@ void SPIClass::setClockDivider(uint8_t divider)
     _spiSettings.clockFreq = spi_getClkFreq(&_spi) / divider;
   }
 
-  spi_init(&_spi, _spiSettings.clockFreq,
-           _spiSettings.dataMode,
-           _spiSettings.bitOrder);
+  spi_init(&_spi, _spiSettings.clockFreq, _spiSettings.dataMode,
+           _spiSettings.bitOrder, _spiSettings.deviceMode);
 }
 
 /**

diff --git a/libraries/SPI/src/SPI.h b/libraries/SPI/src/SPI.h
@@ -43,27 +43,31 @@ extern "C" {
 
 class SPISettings {
   public:
-    constexpr SPISettings(uint32_t clock, BitOrder bitOrder, uint8_t dataMode)
+    constexpr SPISettings(uint32_t clock, BitOrder bitOrder, uint8_t dataMode, SPIDeviceMode deviceMode = SPI_MASTER)
       : clockFreq(clock),
         bitOrder(bitOrder),
-        dataMode((SPIMode)dataMode)
+        dataMode((SPIMode)dataMode),
+        deviceMode(deviceMode)
     { }
-    constexpr SPISettings(uint32_t clock, BitOrder bitOrder, SPIMode dataMode)
+    constexpr SPISettings(uint32_t clock, BitOrder bitOrder, SPIMode dataMode, SPIDeviceMode deviceMode = SPI_MASTER)
       : clockFreq(clock),
         bitOrder(bitOrder),
-        dataMode(dataMode)
+        dataMode(dataMode),
+        deviceMode(deviceMode)
     { }
     constexpr SPISettings()
       : clockFreq(SPI_SPEED_CLOCK_DEFAULT),
         bitOrder(MSBFIRST),
-        dataMode(SPI_MODE0)
+        dataMode(SPI_MODE0),
+        deviceMode(SPI_MASTER)
     { }
 
     bool operator==(const SPISettings &rhs) const
     {
       if ((this->clockFreq == rhs.clockFreq) &&
           (this->bitOrder == rhs.bitOrder) &&
-          (this->dataMode == rhs.dataMode)) {
+          (this->dataMode == rhs.dataMode) &&
+          (this->deviceMode == rhs.deviceMode)) {
         return true;
       }
       return false;
@@ -75,9 +79,10 @@ class SPISettings {
     }
 
   private:
-    uint32_t clockFreq; //specifies the spi bus maximum clock speed
-    BitOrder bitOrder;  //bit order (MSBFirst or LSBFirst)
-    SPIMode  dataMode;  //one of the data mode
+    uint32_t clockFreq;       // specifies the spi bus maximum clock speed
+    BitOrder bitOrder;        // bit order (MSBFirst or LSBFirst)
+    SPIMode  dataMode;        // one of the data mode
+    SPIDeviceMode deviceMode; // device mode: master or slave
 
     friend class SPIClass;
 };
@@ -122,7 +127,7 @@ class SPIClass {
       _spi.pin_ssel = (ssel);
     };
 
-    void begin(void);
+    void begin(SPIDeviceMode device = SPI_MASTER);
     void end(void);
 
     /* This function should be used to configure the SPI instance in case you
@@ -163,6 +168,17 @@ class SPIClass {
       return &(_spi.handle);
     }
 
+    // Dedicated to SPI Slave
+    void attachSlaveInterrupt(uint8_t pin, callback_function_t callback)
+    {
+      ::attachInterrupt(pin, callback, FALLING);
+    }
+
+    void detachSlaveInterrupt(uint8_t pin)
+    {
+      ::detachInterrupt(pin);
+    }
+
   protected:
     // spi instance
     spi_t         _spi;

diff --git a/libraries/SPI/src/utility/spi_com.c b/libraries/SPI/src/utility/spi_com.c
@@ -198,9 +198,10 @@ static uint32_t compute_disable_delay(spi_t *obj)
   * @param  speed : spi output speed
   * @param  mode : one of the spi modes
   * @param  msb : set to 1 in msb first
+  * @param  device : spi device mode: master or slave
   * @retval None
   */
-void spi_init(spi_t *obj, uint32_t speed, SPIMode mode, uint8_t msb)
+void spi_init(spi_t *obj, uint32_t speed, SPIMode mode, uint8_t msb, SPIDeviceMode device)
 {
   if (obj == NULL) {
     return;
@@ -252,8 +253,8 @@ void spi_init(spi_t *obj, uint32_t speed, SPIMode mode, uint8_t msb)
   }
 
   /* Fill default value */
-  handle->Instance               = obj->spi;
-  handle->Init.Mode              = SPI_MODE_MASTER;
+  handle->Instance = obj->spi;
+  handle->Init.Mode = (device == SPI_MASTER) ? SPI_MODE_MASTER : SPI_MODE_SLAVE;
 
   spi_freq = spi_getClkFreqInst(obj->spi);
   /* For SUBGHZSPI,  'SPI_BAUDRATEPRESCALER_*' == 'SUBGHZSPI_BAUDRATEPRESCALER_*' */

diff --git a/libraries/SPI/src/utility/spi_com.h b/libraries/SPI/src/utility/spi_com.h
@@ -74,6 +74,12 @@ typedef enum {
   SPI_MODE3 = 3,
 } SPIMode;
 
+// Device mode
+typedef enum {
+  SPI_MASTER, /* Device is master */
+  SPI_SLAVE   /* Device is slave */
+} SPIDeviceMode;
+
 ///@brief SPI errors
 typedef enum {
   SPI_OK = 0,
@@ -82,7 +88,7 @@ typedef enum {
 } spi_status_e;
 
 /* Exported functions ------------------------------------------------------- */
-void spi_init(spi_t *obj, uint32_t speed, SPIMode mode, uint8_t msb);
+void spi_init(spi_t *obj, uint32_t speed, SPIMode mode, uint8_t msb, SPIDeviceMode device);
 void spi_deinit(spi_t *obj);
 spi_status_e spi_transfer(spi_t *obj, const uint8_t *tx_buffer, uint8_t *rx_buffer, uint16_t len);
 uint32_t spi_getClkFreq(spi_t *obj);