STM32F1: Import (rogerclarkmelbourne) SPI class (#15002)

Marlin/src/HAL/HAL_STM32F1/HAL_spi_STM32F1.cpp

@@ -33,7 +33,7 @@
 #ifdef __STM32F1__
 
 #include "../../inc/MarlinConfig.h"
-#include <SPI.h>
+#include "SPI.h"
 
 // ------------------------
 // Public functions

Marlin/src/HAL/HAL_STM32F1/SPI.cpp

@@ -0,0 +1,741 @@
+/******************************************************************************
+ * The MIT License
+ *
+ * Copyright (c) 2010 Perry Hung.
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy,
+ * modify, merge, publish, distribute, sublicense, and/or sell copies
+ * of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *****************************************************************************/
+
+/**
+ * @author Marti Bolivar <mbolivar@leaflabs.com>
+ * @brief Wirish SPI implementation.
+ */
+
+#ifdef __STM32F1__
+
+#include "SPI.h"
+
+#include <libmaple/timer.h>
+#include <libmaple/util.h>
+#include <libmaple/rcc.h>
+
+#include <boards.h>
+#include <wirish.h>
+
+/** Time in ms for DMA receive timeout */
+#define DMA_TIMEOUT 100
+
+#if CYCLES_PER_MICROSECOND != 72
+  #warning "Unexpected clock speed; SPI frequency calculation will be incorrect"
+#endif
+
+struct spi_pins {
+  uint8_t nss;
+  uint8_t sck;
+  uint8_t miso;
+  uint8_t mosi;
+};
+
+static const spi_pins* dev_to_spi_pins(spi_dev *dev);
+static void configure_gpios(spi_dev *dev, bool as_master);
+static spi_baud_rate determine_baud_rate(spi_dev *dev, uint32_t freq);
+
+#if (BOARD_NR_SPI >= 3) && !defined(STM32_HIGH_DENSITY)
+  #error "The SPI library is misconfigured: 3 SPI ports only available on high density STM32 devices"
+#endif
+
+static const spi_pins board_spi_pins[] __FLASH__ = {
+  #if BOARD_NR_SPI >= 1
+  { BOARD_SPI1_NSS_PIN,
+    BOARD_SPI1_SCK_PIN,
+    BOARD_SPI1_MISO_PIN,
+    BOARD_SPI1_MOSI_PIN },
+  #endif
+  #if BOARD_NR_SPI >= 2
+  { BOARD_SPI2_NSS_PIN,
+    BOARD_SPI2_SCK_PIN,
+    BOARD_SPI2_MISO_PIN,
+    BOARD_SPI2_MOSI_PIN },
+  #endif
+  #if BOARD_NR_SPI >= 3
+  { BOARD_SPI3_NSS_PIN,
+    BOARD_SPI3_SCK_PIN,
+    BOARD_SPI3_MISO_PIN,
+    BOARD_SPI3_MOSI_PIN },
+  #endif
+};
+
+#if BOARD_NR_SPI >= 1
+  static void (*_spi1_this);
+#endif
+#if BOARD_NR_SPI >= 2
+  static void (*_spi2_this);
+#endif
+#if BOARD_NR_SPI >= 3
+  static void (*_spi3_this);
+#endif
+
+/**
+ * Constructor
+ */
+SPIClass::SPIClass(uint32_t spi_num) {
+  _currentSetting=&_settings[spi_num-1];// SPI channels are called 1 2 and 3 but the array is zero indexed
+
+  switch (spi_num) {
+    #if BOARD_NR_SPI >= 1
+      case 1:
+        _currentSetting->spi_d = SPI1;
+        _spi1_this = (void*)this;
+        break;
+    #endif
+    #if BOARD_NR_SPI >= 2
+      case 2:
+        _currentSetting->spi_d = SPI2;
+        _spi2_this = (void*)this;
+        break;
+    #endif
+    #if BOARD_NR_SPI >= 3
+      case 3:
+        _currentSetting->spi_d = SPI3;
+        _spi3_this = (void*)this;
+        break;
+    #endif
+    default: ASSERT(0);
+  }
+
+  // Init things specific to each SPI device
+  // clock divider setup is a bit of hack, and needs to be improved at a later date.
+  #if BOARD_NR_SPI >= 1
+    _settings[0].spi_d = SPI1;
+    _settings[0].clockDivider = determine_baud_rate(_settings[0].spi_d, _settings[0].clock);
+    _settings[0].spiDmaDev = DMA1;
+    _settings[0].spiTxDmaChannel = DMA_CH3;
+    _settings[0].spiRxDmaChannel = DMA_CH2;
+  #endif
+  #if BOARD_NR_SPI >= 2
+    _settings[1].spi_d = SPI2;
+    _settings[1].clockDivider = determine_baud_rate(_settings[1].spi_d, _settings[1].clock);
+    _settings[1].spiDmaDev = DMA1;
+    _settings[1].spiTxDmaChannel = DMA_CH5;
+    _settings[1].spiRxDmaChannel = DMA_CH4;
+  #endif
+  #if BOARD_NR_SPI >= 3
+    _settings[2].spi_d = SPI3;
+    _settings[2].clockDivider = determine_baud_rate(_settings[2].spi_d, _settings[2].clock);
+    _settings[2].spiDmaDev = DMA2;
+    _settings[2].spiTxDmaChannel = DMA_CH2;
+    _settings[2].spiRxDmaChannel = DMA_CH1;
+  #endif
+
+  // added for DMA callbacks.
+  _currentSetting->state = SPI_STATE_IDLE;
+}
+
+/*
+ * Set up/tear down
+ */
+void SPIClass::updateSettings() {
+  uint32_t flags = ((_currentSetting->bitOrder == MSBFIRST ? SPI_FRAME_MSB : SPI_FRAME_LSB) | _currentSetting->dataSize | SPI_SW_SLAVE | SPI_SOFT_SS);
+  spi_master_enable(_currentSetting->spi_d, (spi_baud_rate)_currentSetting->clockDivider, (spi_mode)_currentSetting->dataMode, flags);
+}
+
+void SPIClass::begin() {
+  spi_init(_currentSetting->spi_d);
+  configure_gpios(_currentSetting->spi_d, 1);
+  updateSettings();
+  // added for DMA callbacks.
+  _currentSetting->state = SPI_STATE_READY;
+}
+
+void SPIClass::beginSlave() {
+  spi_init(_currentSetting->spi_d);
+  configure_gpios(_currentSetting->spi_d, 0);
+  uint32_t flags = ((_currentSetting->bitOrder == MSBFIRST ? SPI_FRAME_MSB : SPI_FRAME_LSB) | _currentSetting->dataSize);
+  spi_slave_enable(_currentSetting->spi_d, (spi_mode)_currentSetting->dataMode, flags);
+  // added for DMA callbacks.
+  _currentSetting->state = SPI_STATE_READY;
+}
+
+void SPIClass::end() {
+  if (!spi_is_enabled(_currentSetting->spi_d))
+    return;
+
+  // Follows RM0008's sequence for disabling a SPI in master/slave
+  // full duplex mode.
+  while (spi_is_rx_nonempty(_currentSetting->spi_d)) {
+    // FIXME [0.1.0] remove this once you have an interrupt based driver
+    volatile uint16_t rx __attribute__((unused)) = spi_rx_reg(_currentSetting->spi_d);
+  }
+  while (!spi_is_tx_empty(_currentSetting->spi_d)) {};
+  while (spi_is_busy(_currentSetting->spi_d)) {};
+
+  spi_peripheral_disable(_currentSetting->spi_d);
+  // added for DMA callbacks.
+  // Need to add unsetting the callbacks for the DMA channels.
+  _currentSetting->state = SPI_STATE_IDLE;
+}
+
+/* Roger Clark added  3 functions */
+void SPIClass::setClockDivider(uint32_t clockDivider) {
+  _currentSetting->clockDivider = clockDivider;
+  uint32_t cr1 = _currentSetting->spi_d->regs->CR1 & ~(SPI_CR1_BR);
+  _currentSetting->spi_d->regs->CR1 = cr1 | (clockDivider & SPI_CR1_BR);
+}
+
+void SPIClass::setBitOrder(BitOrder bitOrder) {
+  _currentSetting->bitOrder = bitOrder;
+  uint32_t cr1 = _currentSetting->spi_d->regs->CR1 & ~(SPI_CR1_LSBFIRST);
+  if (bitOrder == LSBFIRST) cr1 |= SPI_CR1_LSBFIRST;
+  _currentSetting->spi_d->regs->CR1 = cr1;
+}
+
+/*  Victor Perez. Added to test changing datasize from 8 to 16 bit modes on the fly.
+* Input parameter should be SPI_CR1_DFF set to 0 or 1 on a 32bit word.
+*
+*/
+void SPIClass::setDataSize(uint32_t datasize) {
+  _currentSetting->dataSize = datasize;
+  uint32_t cr1 = _currentSetting->spi_d->regs->CR1 & ~(SPI_CR1_DFF);
+  uint8_t en = spi_is_enabled(_currentSetting->spi_d);
+  spi_peripheral_disable(_currentSetting->spi_d);
+  _currentSetting->spi_d->regs->CR1 = cr1 | (datasize & SPI_CR1_DFF) | en;
+}
+
+void SPIClass::setDataMode(uint8_t dataMode) {
+  /* Notes:
+  As far as I can tell, the AVR numbers for dataMode appear to match the numbers required by the STM32
+  From the AVR doc http://www.atmel.com/images/doc2585.pdf section 2.4
+  SPI Mode  CPOL  CPHA  Shift SCK-edge  Capture SCK-edge
+  0       0     0     Falling     Rising
+  1       0     1     Rising      Falling
+  2       1     0     Rising      Falling
+  3       1     1     Falling     Rising
+
+  On the STM32 it appears to be
+
+  bit 1 - CPOL : Clock polarity
+    (This bit should not be changed when communication is ongoing)
+    0 : CLK to 0 when idle
+    1 : CLK to 1 when idle
+
+  bit 0 - CPHA : Clock phase
+    (This bit should not be changed when communication is ongoing)
+    0 : The first clock transition is the first data capture edge
+    1 : The second clock transition is the first data capture edge
+
+  If someone finds this is not the case or sees a logic error with this let me know ;-)
+  */
+  _currentSetting->dataMode = dataMode;
+  uint32_t cr1 = _currentSetting->spi_d->regs->CR1 & ~(SPI_CR1_CPOL|SPI_CR1_CPHA);
+  _currentSetting->spi_d->regs->CR1 = cr1 | (dataMode & (SPI_CR1_CPOL|SPI_CR1_CPHA));
+}
+
+void SPIClass::beginTransaction(uint8_t pin, SPISettings settings) {
+  setBitOrder(settings.bitOrder);
+  setDataMode(settings.dataMode);
+  setDataSize(settings.dataSize);
+  setClockDivider(determine_baud_rate(_currentSetting->spi_d, settings.clock));
+  begin();
+}
+
+void SPIClass::beginTransactionSlave(SPISettings settings) {
+  setBitOrder(settings.bitOrder);
+  setDataMode(settings.dataMode);
+  setDataSize(settings.dataSize);
+  beginSlave();
+}
+
+void SPIClass::endTransaction() { }
+
+
+/*
+ * I/O
+ */
+
+uint16_t SPIClass::read() {
+  while ( spi_is_rx_nonempty(_currentSetting->spi_d)==0 ) ;
+  return (uint16)spi_rx_reg(_currentSetting->spi_d);
+}
+
+void SPIClass::read(uint8_t *buf, uint32_t len) {
+  if (len == 0) return;
+  spi_rx_reg(_currentSetting->spi_d);   // clear the RX buffer in case a byte is waiting on it.
+  spi_reg_map * regs = _currentSetting->spi_d->regs;
+  // start sequence: write byte 0
+  regs->DR = 0x00FF;            // write the first byte
+  // main loop
+  while ( (--len) ) {
+    while( !(regs->SR & SPI_SR_TXE) ); // wait for TXE flag
+    noInterrupts();    // go atomic level - avoid interrupts to surely get the previously received data
+    regs->DR = 0x00FF; // write the next data item to be transmitted into the SPI_DR register. This clears the TXE flag.
+    while ( !(regs->SR & SPI_SR_RXNE) ); // wait till data is available in the DR register
+    *buf++ = (uint8)(regs->DR); // read and store the received byte. This clears the RXNE flag.
+    interrupts();      // let systick do its job
+  }
+  // read remaining last byte
+  while ( !(regs->SR & SPI_SR_RXNE) ) {} // wait till data is available in the Rx register
+  *buf++ = (uint8)(regs->DR);  // read and store the received byte
+}
+
+void SPIClass::write(uint16_t data) {
+  /* Added for 16bit data Victor Perez. Roger Clark
+   * Improved speed by just directly writing the single byte to the SPI data reg and wait for completion,
+   * by taking the Tx code from transfer(byte)
+   * This almost doubles the speed of this function.
+   */
+  spi_tx_reg(_currentSetting->spi_d, data); // write the data to be transmitted into the SPI_DR register (this clears the TXE flag)
+  while (spi_is_tx_empty(_currentSetting->spi_d) == 0); // "5. Wait until TXE=1 ..."
+  while (spi_is_busy(_currentSetting->spi_d) != 0); // "... and then wait until BSY=0 before disabling the SPI."
+}
+
+void SPIClass::write16(uint16_t data) {
+  // Added by stevestrong: write two consecutive bytes in 8 bit mode (DFF=0)
+  spi_tx_reg(_currentSetting->spi_d, data>>8); // write high byte
+  while (spi_is_tx_empty(_currentSetting->spi_d) == 0); // Wait until TXE=1
+  spi_tx_reg(_currentSetting->spi_d, data); // write low byte
+  while (spi_is_tx_empty(_currentSetting->spi_d) == 0); // Wait until TXE=1
+  while (spi_is_busy(_currentSetting->spi_d) != 0); // wait until BSY=0
+}
+
+void SPIClass::write(uint16_t data, uint32_t n) {
+  // Added by stevstrong: Repeatedly send same data by the specified number of times
+  spi_reg_map * regs = _currentSetting->spi_d->regs;
+  while ( (n--)>0 ) {
+    regs->DR = data; // write the data to be transmitted into the SPI_DR register (this clears the TXE flag)
+    while ( (regs->SR & SPI_SR_TXE)==0 ) ; // wait till Tx empty
+  }
+  while ( (regs->SR & SPI_SR_BSY) != 0); // wait until BSY=0 before returning
+}
+
+void SPIClass::write(const void *data, uint32_t length) {
+  spi_dev * spi_d = _currentSetting->spi_d;
+  spi_tx(spi_d, data, length); // data can be array of bytes or words
+  while (spi_is_tx_empty(spi_d) == 0); // "5. Wait until TXE=1 ..."
+  while (spi_is_busy(spi_d) != 0); // "... and then wait until BSY=0 before disabling the SPI."
+}
+
+uint8_t SPIClass::transfer(uint8_t byte) const {
+  spi_dev * spi_d = _currentSetting->spi_d;
+  spi_rx_reg(spi_d); // read any previous data
+  spi_tx_reg(spi_d, byte); // Write the data item to be transmitted into the SPI_DR register
+  while (spi_is_tx_empty(spi_d) == 0); // "5. Wait until TXE=1 ..."
+  while (spi_is_busy(spi_d) != 0); // "... and then wait until BSY=0 before disabling the SPI."
+  return (uint8)spi_rx_reg(spi_d); // "... and read the last received data."
+}
+
+uint16_t SPIClass::transfer16(uint16_t data) const {
+  // Modified by stevestrong: write & read two consecutive bytes in 8 bit mode (DFF=0)
+  // This is more effective than two distinct byte transfers
+  spi_dev * spi_d = _currentSetting->spi_d;
+  spi_rx_reg(spi_d);                   // read any previous data
+  spi_tx_reg(spi_d, data>>8);          // write high byte
+  while (spi_is_tx_empty(spi_d) == 0); // wait until TXE=1
+  while (spi_is_busy(spi_d) != 0);     // wait until BSY=0
+  uint16_t ret = spi_rx_reg(spi_d)<<8; // read and shift high byte
+  spi_tx_reg(spi_d, data);             // write low byte
+  while (spi_is_tx_empty(spi_d) == 0); // wait until TXE=1
+  while (spi_is_busy(spi_d) != 0);     // wait until BSY=0
+  ret += spi_rx_reg(spi_d);            // read low byte
+  return ret;
+}
+
+/*  Roger Clark and Victor Perez, 2015
+* Performs a DMA SPI transfer with at least a receive buffer.
+* If a TX buffer is not provided, FF is sent over and over for the lenght of the transfer.
+* On exit TX buffer is not modified, and RX buffer cotains the received data.
+* Still in progress.
+*/
+void SPIClass::dmaTransferSet(const void *transmitBuf, void *receiveBuf) {
+  dma_init(_currentSetting->spiDmaDev);
+  //spi_rx_dma_enable(_currentSetting->spi_d);
+  //spi_tx_dma_enable(_currentSetting->spi_d);
+  dma_xfer_size dma_bit_size = (_currentSetting->dataSize==DATA_SIZE_16BIT) ? DMA_SIZE_16BITS : DMA_SIZE_8BITS;
+  dma_setup_transfer(_currentSetting->spiDmaDev, _currentSetting->spiRxDmaChannel, &_currentSetting->spi_d->regs->DR,
+      dma_bit_size, receiveBuf, dma_bit_size, (DMA_MINC_MODE | DMA_TRNS_CMPLT ));// receive buffer DMA
+  if (!transmitBuf) {
+    transmitBuf = &ff;
+    dma_setup_transfer(_currentSetting->spiDmaDev, _currentSetting->spiTxDmaChannel, &_currentSetting->spi_d->regs->DR,
+        dma_bit_size, (volatile void*)transmitBuf, dma_bit_size, (DMA_FROM_MEM));// Transmit FF repeatedly
+  }
+  else {
+    dma_setup_transfer(_currentSetting->spiDmaDev, _currentSetting->spiTxDmaChannel, &_currentSetting->spi_d->regs->DR,
+        dma_bit_size, (volatile void*)transmitBuf, dma_bit_size, (DMA_MINC_MODE |  DMA_FROM_MEM ));// Transmit buffer DMA
+  }
+  dma_set_priority(_currentSetting->spiDmaDev, _currentSetting->spiTxDmaChannel, DMA_PRIORITY_LOW);
+  dma_set_priority(_currentSetting->spiDmaDev, _currentSetting->spiRxDmaChannel, DMA_PRIORITY_VERY_HIGH);
+}
+
+uint8_t SPIClass::dmaTransferRepeat(uint16_t length) {
+  if (length == 0) return 0;
+  if (spi_is_rx_nonempty(_currentSetting->spi_d) == 1) spi_rx_reg(_currentSetting->spi_d);
+  _currentSetting->state = SPI_STATE_TRANSFER;
+  dma_set_num_transfers(_currentSetting->spiDmaDev, _currentSetting->spiRxDmaChannel, length);
+  dma_set_num_transfers(_currentSetting->spiDmaDev, _currentSetting->spiTxDmaChannel, length);
+  dma_enable(_currentSetting->spiDmaDev, _currentSetting->spiRxDmaChannel);// enable receive
+  dma_enable(_currentSetting->spiDmaDev, _currentSetting->spiTxDmaChannel);// enable transmit
+  spi_rx_dma_enable(_currentSetting->spi_d);
+  spi_tx_dma_enable(_currentSetting->spi_d);
+  if (_currentSetting->receiveCallback)
+    return 0;
+
+  //uint32_t m = millis();
+  uint8_t b = 0;
+  uint32_t m = millis();
+  while ((dma_get_isr_bits(_currentSetting->spiDmaDev, _currentSetting->spiTxDmaChannel) & DMA_ISR_TCIF1) == 0) {
+    //Avoid interrupts and just loop waiting for the flag to be set.
+    if ((millis() - m) > DMA_TIMEOUT) { b = 2; break; }
+  }
+
+  while (spi_is_tx_empty(_currentSetting->spi_d) == 0); // "5. Wait until TXE=1 ..."
+  while (spi_is_busy(_currentSetting->spi_d) != 0); // "... and then wait until BSY=0 before disabling the SPI."
+  spi_tx_dma_disable(_currentSetting->spi_d);
+  spi_rx_dma_disable(_currentSetting->spi_d);
+  dma_disable(_currentSetting->spiDmaDev, _currentSetting->spiTxDmaChannel);
+  dma_disable(_currentSetting->spiDmaDev, _currentSetting->spiRxDmaChannel);
+  dma_clear_isr_bits(_currentSetting->spiDmaDev, _currentSetting->spiRxDmaChannel);
+  dma_clear_isr_bits(_currentSetting->spiDmaDev, _currentSetting->spiTxDmaChannel);
+  _currentSetting->state = SPI_STATE_READY;
+  return b;
+}
+
+/* Roger Clark and Victor Perez, 2015
+ * Performs a DMA SPI transfer with at least a receive buffer.
+ * If a TX buffer is not provided, FF is sent over and over for the length of the transfer.
+ * On exit TX buffer is not modified, and RX buffer contains the received data.
+ * Still in progress.
+ */
+uint8_t SPIClass::dmaTransfer(const void *transmitBuf, void *receiveBuf, uint16_t length) {
+  dmaTransferSet(transmitBuf, receiveBuf);
+  return dmaTransferRepeat(length);
+}
+
+/* Roger Clark and Victor Perez, 2015
+ * Performs a DMA SPI send using a TX buffer.
+ * On exit TX buffer is not modified.
+ * Still in progress.
+ * 2016 - stevstrong - reworked to automatically detect bit size from SPI setting
+ */
+void SPIClass::dmaSendSet(const void * transmitBuf, bool minc) {
+  uint32_t flags = ( (DMA_MINC_MODE*minc) | DMA_FROM_MEM | DMA_TRNS_CMPLT);
+  dma_init(_currentSetting->spiDmaDev);
+  dma_xfer_size dma_bit_size = (_currentSetting->dataSize==DATA_SIZE_16BIT) ? DMA_SIZE_16BITS : DMA_SIZE_8BITS;
+  dma_setup_transfer(_currentSetting->spiDmaDev, _currentSetting->spiTxDmaChannel, &_currentSetting->spi_d->regs->DR, dma_bit_size,
+             (volatile void*)transmitBuf, dma_bit_size, flags);// Transmit buffer DMA
+  dma_set_priority(_currentSetting->spiDmaDev, _currentSetting->spiTxDmaChannel, DMA_PRIORITY_LOW);
+}
+
+uint8_t SPIClass::dmaSendRepeat(uint16_t length) {
+  if (length == 0) return 0;
+
+  dma_clear_isr_bits(_currentSetting->spiDmaDev, _currentSetting->spiTxDmaChannel);
+  dma_set_num_transfers(_currentSetting->spiDmaDev, _currentSetting->spiTxDmaChannel, length);
+  _currentSetting->state = SPI_STATE_TRANSMIT;
+  dma_enable(_currentSetting->spiDmaDev, _currentSetting->spiTxDmaChannel);// enable transmit
+  spi_tx_dma_enable(_currentSetting->spi_d);
+  if (_currentSetting->transmitCallback)
+    return 0;
+
+  uint32_t m = millis();
+  uint8_t b = 0;
+  while ((dma_get_isr_bits(_currentSetting->spiDmaDev, _currentSetting->spiTxDmaChannel) & DMA_ISR_TCIF1)==0) {
+    //Avoid interrupts and just loop waiting for the flag to be set.
+    if ((millis() - m) > DMA_TIMEOUT) { b = 2; break; }
+  }
+  while (spi_is_tx_empty(_currentSetting->spi_d) == 0); // "5. Wait until TXE=1 ..."
+  while (spi_is_busy(_currentSetting->spi_d) != 0); // "... and then wait until BSY=0 before disabling the SPI."
+  spi_tx_dma_disable(_currentSetting->spi_d);
+  dma_disable(_currentSetting->spiDmaDev, _currentSetting->spiTxDmaChannel);
+  dma_clear_isr_bits(_currentSetting->spiDmaDev, _currentSetting->spiTxDmaChannel);
+  _currentSetting->state = SPI_STATE_READY;
+  return b;
+}
+
+uint8_t SPIClass::dmaSend(const void * transmitBuf, uint16_t length, bool minc) {
+  dmaSendSet(transmitBuf, minc);
+  return dmaSendRepeat(length);
+}
+
+uint8_t SPIClass::dmaSendAsync(const void * transmitBuf, uint16_t length, bool minc) {
+  uint8_t b = 0;
+
+  if (_currentSetting->state != SPI_STATE_READY) {
+    uint32_t m = millis();
+    while ((dma_get_isr_bits(_currentSetting->spiDmaDev, _currentSetting->spiTxDmaChannel) & DMA_ISR_TCIF1)==0) {
+      //Avoid interrupts and just loop waiting for the flag to be set.
+      //delayMicroseconds(10);
+      if ((millis() - m) > DMA_TIMEOUT) { b = 2; break; }
+    }
+
+    while (spi_is_tx_empty(_currentSetting->spi_d) == 0); // "5. Wait until TXE=1 ..."
+    while (spi_is_busy(_currentSetting->spi_d) != 0); // "... and then wait until BSY=0 before disabling the SPI."
+    spi_tx_dma_disable(_currentSetting->spi_d);
+    dma_disable(_currentSetting->spiDmaDev, _currentSetting->spiTxDmaChannel);
+    _currentSetting->state = SPI_STATE_READY;
+  }
+
+  if (length == 0) return 0;
+  uint32_t flags = ( (DMA_MINC_MODE*minc) | DMA_FROM_MEM | DMA_TRNS_CMPLT);
+
+  dma_init(_currentSetting->spiDmaDev);
+  // TX
+  dma_xfer_size dma_bit_size = (_currentSetting->dataSize==DATA_SIZE_16BIT) ? DMA_SIZE_16BITS : DMA_SIZE_8BITS;
+  dma_setup_transfer(_currentSetting->spiDmaDev, _currentSetting->spiTxDmaChannel, &_currentSetting->spi_d->regs->DR,
+      dma_bit_size, (volatile void*)transmitBuf, dma_bit_size, flags);// Transmit buffer DMA
+  dma_set_num_transfers(_currentSetting->spiDmaDev, _currentSetting->spiTxDmaChannel, length);
+  dma_clear_isr_bits(_currentSetting->spiDmaDev, _currentSetting->spiTxDmaChannel);
+  dma_enable(_currentSetting->spiDmaDev, _currentSetting->spiTxDmaChannel);// enable transmit
+  spi_tx_dma_enable(_currentSetting->spi_d);
+
+  _currentSetting->state = SPI_STATE_TRANSMIT;
+  return b;
+}
+
+
+/**
+ *  New functions added to manage callbacks.
+ *  Victor Perez 2017
+ */
+void SPIClass::onReceive(void(*callback)(void)) {
+  _currentSetting->receiveCallback = callback;
+  if (callback) {
+    switch (_currentSetting->spi_d->clk_id) {
+    #if BOARD_NR_SPI >= 1
+    case RCC_SPI1:
+      dma_attach_interrupt(_currentSetting->spiDmaDev, _currentSetting->spiRxDmaChannel, &SPIClass::_spi1EventCallback);
+      break;
+    #endif
+    #if BOARD_NR_SPI >= 2
+    case RCC_SPI2:
+      dma_attach_interrupt(_currentSetting->spiDmaDev, _currentSetting->spiRxDmaChannel, &SPIClass::_spi2EventCallback);
+      break;
+    #endif
+    #if BOARD_NR_SPI >= 3
+    case RCC_SPI3:
+      dma_attach_interrupt(_currentSetting->spiDmaDev, _currentSetting->spiRxDmaChannel, &SPIClass::_spi3EventCallback);
+      break;
+    #endif
+    default:
+      ASSERT(0);
+    }
+  }
+  else {
+    dma_detach_interrupt(_currentSetting->spiDmaDev, _currentSetting->spiRxDmaChannel);
+  }
+}
+
+void SPIClass::onTransmit(void(*callback)(void)) {
+  _currentSetting->transmitCallback = callback;
+  if (callback) {
+    switch (_currentSetting->spi_d->clk_id) {
+    #if BOARD_NR_SPI >= 1
+    case RCC_SPI1:
+      dma_attach_interrupt(_currentSetting->spiDmaDev, _currentSetting->spiTxDmaChannel, &SPIClass::_spi1EventCallback);
+      break;
+    #endif
+    #if BOARD_NR_SPI >= 2
+     case RCC_SPI2:
+      dma_attach_interrupt(_currentSetting->spiDmaDev, _currentSetting->spiTxDmaChannel, &SPIClass::_spi2EventCallback);
+      break;
+    #endif
+    #if BOARD_NR_SPI >= 3
+    case RCC_SPI3:
+      dma_attach_interrupt(_currentSetting->spiDmaDev, _currentSetting->spiTxDmaChannel, &SPIClass::_spi3EventCallback);
+      break;
+    #endif
+    default:
+      ASSERT(0);
+    }
+  }
+  else {
+    dma_detach_interrupt(_currentSetting->spiDmaDev, _currentSetting->spiTxDmaChannel);
+  }
+}
+
+/**
+ * TODO: check if better to first call the customer code, next disable the DMA requests.
+ * Also see if we need to check whether callbacks are set or not, may be better to be checked
+ * during the initial setup and only set the callback to EventCallback if they are set.
+ */
+void SPIClass::EventCallback() {
+  while (spi_is_tx_empty(_currentSetting->spi_d) == 0); // "5. Wait until TXE=1 ..."
+  while (spi_is_busy(_currentSetting->spi_d) != 0); // "... and then wait until BSY=0"
+  switch (_currentSetting->state) {
+  case SPI_STATE_TRANSFER:
+    while (spi_is_rx_nonempty(_currentSetting->spi_d));
+    _currentSetting->state = SPI_STATE_READY;
+    spi_tx_dma_disable(_currentSetting->spi_d);
+    spi_rx_dma_disable(_currentSetting->spi_d);
+    //dma_disable(_currentSetting->spiDmaDev, _currentSetting->spiTxDmaChannel);
+    //dma_disable(_currentSetting->spiDmaDev, _currentSetting->spiRxDmaChannel);
+    if (_currentSetting->receiveCallback)
+      _currentSetting->receiveCallback();
+    break;
+  case SPI_STATE_TRANSMIT:
+    _currentSetting->state = SPI_STATE_READY;
+    spi_tx_dma_disable(_currentSetting->spi_d);
+    //dma_disable(_currentSetting->spiDmaDev, _currentSetting->spiTxDmaChannel);
+    if (_currentSetting->transmitCallback)
+      _currentSetting->transmitCallback();
+    break;
+  default:
+    break;
+  }
+}
+
+void SPIClass::attachInterrupt() {
+  // Should be enableInterrupt()
+}
+
+void SPIClass::detachInterrupt() {
+  // Should be disableInterrupt()
+}
+
+/*
+ * Pin accessors
+ */
+
+uint8_t SPIClass::misoPin() {
+  return dev_to_spi_pins(_currentSetting->spi_d)->miso;
+}
+
+uint8_t SPIClass::mosiPin() {
+  return dev_to_spi_pins(_currentSetting->spi_d)->mosi;
+}
+
+uint8_t SPIClass::sckPin() {
+  return dev_to_spi_pins(_currentSetting->spi_d)->sck;
+}
+
+uint8_t SPIClass::nssPin() {
+  return dev_to_spi_pins(_currentSetting->spi_d)->nss;
+}
+
+/*
+ * Deprecated functions
+ */
+
+uint8_t SPIClass::send(uint8_t data) {
+  this->write(data);
+  return 1;
+}
+
+uint8_t SPIClass::send(uint8_t *buf, uint32_t len) {
+  this->write(buf, len);
+  return len;
+}
+
+uint8_t SPIClass::recv() {
+  return this->read();
+}
+
+/*
+ * DMA call back functions, one per port.
+ */
+#if BOARD_NR_SPI >= 1
+  void SPIClass::_spi1EventCallback() {
+    reinterpret_cast<class SPIClass*>(_spi1_this)->EventCallback();
+  }
+#endif
+#if BOARD_NR_SPI >= 2
+  void SPIClass::_spi2EventCallback() {
+    reinterpret_cast<class SPIClass*>(_spi2_this)->EventCallback();
+  }
+#endif
+#if BOARD_NR_SPI >= 3
+  void SPIClass::_spi3EventCallback() {
+    reinterpret_cast<class SPIClass*>(_spi3_this)->EventCallback();
+  }
+#endif
+
+/*
+ * Auxiliary functions
+ */
+static const spi_pins* dev_to_spi_pins(spi_dev *dev) {
+  switch (dev->clk_id) {
+    #if BOARD_NR_SPI >= 1
+      case RCC_SPI1: return board_spi_pins;
+    #endif
+    #if BOARD_NR_SPI >= 2
+      case RCC_SPI2: return board_spi_pins + 1;
+    #endif
+    #if BOARD_NR_SPI >= 3
+      case RCC_SPI3: return board_spi_pins + 2;
+    #endif
+    default: return NULL;
+  }
+}
+
+static void disable_pwm(const stm32_pin_info *i) {
+  if (i->timer_device)
+    timer_set_mode(i->timer_device, i->timer_channel, TIMER_DISABLED);
+}
+
+static void configure_gpios(spi_dev *dev, bool as_master) {
+  const spi_pins *pins = dev_to_spi_pins(dev);
+  if (!pins) return;
+
+  const stm32_pin_info *nssi = &PIN_MAP[pins->nss],
+                       *scki = &PIN_MAP[pins->sck],
+                       *misoi = &PIN_MAP[pins->miso],
+                       *mosii = &PIN_MAP[pins->mosi];
+
+  disable_pwm(nssi);
+  disable_pwm(scki);
+  disable_pwm(misoi);
+  disable_pwm(mosii);
+
+  spi_config_gpios(dev, as_master, nssi->gpio_device, nssi->gpio_bit,
+  scki->gpio_device, scki->gpio_bit, misoi->gpio_bit,
+  mosii->gpio_bit);
+}
+
+static const spi_baud_rate baud_rates[8] __FLASH__ = {
+  SPI_BAUD_PCLK_DIV_2,
+  SPI_BAUD_PCLK_DIV_4,
+  SPI_BAUD_PCLK_DIV_8,
+  SPI_BAUD_PCLK_DIV_16,
+  SPI_BAUD_PCLK_DIV_32,
+  SPI_BAUD_PCLK_DIV_64,
+  SPI_BAUD_PCLK_DIV_128,
+  SPI_BAUD_PCLK_DIV_256,
+};
+
+/*
+* Note: This assumes you're on a LeafLabs-style board
+* (CYCLES_PER_MICROSECOND == 72, APB2 at 72MHz, APB1 at 36MHz).
+*/
+static spi_baud_rate determine_baud_rate(spi_dev *dev, uint32_t freq) {
+  uint32_t clock = 0;
+  switch (rcc_dev_clk(dev->clk_id)) {
+    case RCC_AHB:
+    case RCC_APB2: clock = STM32_PCLK2; break; // 72 Mhz
+    case RCC_APB1: clock = STM32_PCLK1; break; // 36 Mhz
+  }
+  clock >>= 1;
+
+  uint8_t i = 0;
+  while (i < 7 && freq < clock) { clock >>= 1; i++; }
+  return baud_rates[i];
+}
+
+SPIClass SPI(1);
+
+#endif // __STM32F1__

Marlin/src/HAL/HAL_STM32F1/SPI.h

@@ -0,0 +1,409 @@
+/******************************************************************************
+ * The MIT License
+ *
+ * Copyright (c) 2010 Perry Hung.
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy,
+ * modify, merge, publish, distribute, sublicense, and/or sell copies
+ * of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *****************************************************************************/
+#pragma once
+
+#include <libmaple/libmaple_types.h>
+#include <libmaple/spi.h>
+#include <libmaple/dma.h>
+
+#include <boards.h>
+#include <stdint.h>
+#include <wirish.h>
+
+// SPI_HAS_TRANSACTION means SPI has
+//   - beginTransaction()
+//   - endTransaction()
+//   - usingInterrupt()
+//   - SPISetting(clock, bitOrder, dataMode)
+//#define SPI_HAS_TRANSACTION
+
+#define SPI_CLOCK_DIV2   SPI_BAUD_PCLK_DIV_2
+#define SPI_CLOCK_DIV4   SPI_BAUD_PCLK_DIV_4
+#define SPI_CLOCK_DIV8   SPI_BAUD_PCLK_DIV_8
+#define SPI_CLOCK_DIV16  SPI_BAUD_PCLK_DIV_16
+#define SPI_CLOCK_DIV32  SPI_BAUD_PCLK_DIV_32
+#define SPI_CLOCK_DIV64  SPI_BAUD_PCLK_DIV_64
+#define SPI_CLOCK_DIV128 SPI_BAUD_PCLK_DIV_128
+#define SPI_CLOCK_DIV256 SPI_BAUD_PCLK_DIV_256
+
+/*
+ * Roger Clark. 20150106
+ * Commented out redundant AVR defined
+ *
+#define SPI_MODE_MASK 0x0C     // CPOL = bit 3, CPHA = bit 2 on SPCR
+#define SPI_CLOCK_MASK 0x03    // SPR1 = bit 1, SPR0 = bit 0 on SPCR
+#define SPI_2XCLOCK_MASK 0x01  // SPI2X = bit 0 on SPSR
+
+// define SPI_AVR_EIMSK for AVR boards with external interrupt pins
+#if defined(EIMSK)
+  #define SPI_AVR_EIMSK EIMSK
+#elif defined(GICR)
+  #define SPI_AVR_EIMSK GICR
+#elif defined(GIMSK)
+  #define SPI_AVR_EIMSK GIMSK
+#endif
+*/
+
+#ifndef STM32_LSBFIRST
+  #define STM32_LSBFIRST 0
+#endif
+#ifndef STM32_MSBFIRST
+  #define STM32_MSBFIRST 1
+#endif
+
+// PC13 or PA4
+#define BOARD_SPI_DEFAULT_SS PA4
+//#define BOARD_SPI_DEFAULT_SS PC13
+
+#define SPI_MODE0 SPI_MODE_0
+#define SPI_MODE1 SPI_MODE_1
+#define SPI_MODE2 SPI_MODE_2
+#define SPI_MODE3 SPI_MODE_3
+
+#define DATA_SIZE_8BIT SPI_CR1_DFF_8_BIT
+#define DATA_SIZE_16BIT SPI_CR1_DFF_16_BIT
+
+typedef enum {
+  SPI_STATE_IDLE,
+  SPI_STATE_READY,
+  SPI_STATE_RECEIVE,
+  SPI_STATE_TRANSMIT,
+  SPI_STATE_TRANSFER
+} spi_mode_t;
+
+class SPISettings {
+public:
+  SPISettings(uint32_t clock, BitOrder bitOrder, uint8_t dataMode) {
+    if (__builtin_constant_p(clock))
+      init_AlwaysInline(clock, bitOrder, dataMode, DATA_SIZE_8BIT);
+    else
+      init_MightInline(clock, bitOrder, dataMode, DATA_SIZE_8BIT);
+  }
+  SPISettings(uint32_t clock, BitOrder bitOrder, uint8_t dataMode, uint32_t dataSize) {
+    if (__builtin_constant_p(clock))
+      init_AlwaysInline(clock, bitOrder, dataMode, dataSize);
+    else
+      init_MightInline(clock, bitOrder, dataMode, dataSize);
+  }
+  SPISettings(uint32_t clock) {
+    if (__builtin_constant_p(clock))
+      init_AlwaysInline(clock, MSBFIRST, SPI_MODE0, DATA_SIZE_8BIT);
+    else
+      init_MightInline(clock, MSBFIRST, SPI_MODE0, DATA_SIZE_8BIT);
+  }
+  SPISettings() {
+    init_AlwaysInline(4000000, MSBFIRST, SPI_MODE0, DATA_SIZE_8BIT);
+  }
+private:
+  void init_MightInline(uint32_t clock, BitOrder bitOrder, uint8_t dataMode, uint32_t dataSize) {
+    init_AlwaysInline(clock, bitOrder, dataMode, dataSize);
+  }
+  void init_AlwaysInline(uint32_t clock, BitOrder bitOrder, uint8_t dataMode, uint32_t dataSize) __attribute__((__always_inline__)) {
+    this->clock = clock;
+    this->bitOrder = bitOrder;
+    this->dataMode = dataMode;
+    this->dataSize = dataSize;
+  }
+  uint32_t clock;
+  uint32_t dataSize;
+  uint32_t clockDivider;
+  BitOrder bitOrder;
+  uint8_t dataMode;
+  uint8_t _SSPin;
+  volatile spi_mode_t state;
+  spi_dev *spi_d;
+  dma_channel spiRxDmaChannel, spiTxDmaChannel;
+  dma_dev* spiDmaDev;
+  void (*receiveCallback)(void) = NULL;
+  void (*transmitCallback)(void) = NULL;
+
+  friend class SPIClass;
+};
+
+/*
+ * Kept for compat.
+ */
+static const uint8_t ff = 0xFF;
+
+/**
+ * @brief Wirish SPI interface.
+ *
+ * This implementation uses software slave management, so the caller
+ * is responsible for controlling the slave select line.
+ */
+class SPIClass {
+
+public:
+  /**
+   * @param spiPortNumber Number of the SPI port to manage.
+   */
+  SPIClass(uint32_t spiPortNumber);
+
+  /**
+   * @brief Equivalent to begin(SPI_1_125MHZ, MSBFIRST, 0).
+   */
+  void begin();
+
+  /**
+   * @brief Turn on a SPI port and set its GPIO pin modes for use as a slave.
+   *
+   * SPI port is enabled in full duplex mode, with software slave management.
+   *
+   * @param bitOrder Either LSBFIRST (little-endian) or MSBFIRST(big-endian)
+   * @param mode SPI mode to use
+   */
+  void beginSlave(uint32_t bitOrder, uint32_t mode);
+
+  /**
+   * @brief Equivalent to beginSlave(MSBFIRST, 0).
+   */
+  void beginSlave();
+
+  /**
+   * @brief Disables the SPI port, but leaves its GPIO pin modes unchanged.
+   */
+  void end();
+
+  void beginTransaction(SPISettings settings) { beginTransaction(BOARD_SPI_DEFAULT_SS, settings); }
+  void beginTransaction(uint8_t pin, SPISettings settings);
+  void endTransaction();
+
+  void beginTransactionSlave(SPISettings settings);
+
+  void setClockDivider(uint32_t clockDivider);
+  void setBitOrder(BitOrder bitOrder);
+  void setDataMode(uint8_t dataMode);
+
+  // SPI Configuration methods
+  void attachInterrupt();
+  void detachInterrupt();
+
+  /* Victor Perez. Added to change datasize from 8 to 16 bit modes on the fly.
+   * Input parameter should be SPI_CR1_DFF set to 0 or 1 on a 32bit word.
+   * Requires an added function spi_data_size on STM32F1 / cores / maple / libmaple / spi.c
+   */
+  void setDataSize(uint32_t ds);
+
+  /* Victor Perez 2017. Added to set and clear callback functions for callback
+   * on DMA transfer completion.
+   * onReceive used to set the callback in case of dmaTransfer (tx/rx), once rx is completed
+   * onTransmit used to set the callback in case of dmaSend (tx only). That function
+   * will NOT be called in case of TX/RX
+   */
+  void onReceive(void(*)(void));
+  void onTransmit(void(*)(void));
+
+  /*
+   * I/O
+   */
+
+  /**
+   * @brief Return the next unread byte/word.
+   *
+   * If there is no unread byte/word waiting, this function will block
+   * until one is received.
+   */
+  uint16_t read();
+
+  /**
+   * @brief Read length bytes, storing them into buffer.
+   * @param buffer Buffer to store received bytes into.
+   * @param length Number of bytes to store in buffer. This
+   *               function will block until the desired number of
+   *               bytes have been read.
+   */
+  void read(uint8_t *buffer, uint32_t length);
+
+  /**
+   * @brief Transmit one byte/word.
+   * @param data to transmit.
+   */
+  void write(uint16_t data);
+  void write16(uint16_t data); // write 2 bytes in 8 bit mode (DFF=0)
+
+  /**
+   * @brief Transmit one byte/word a specified number of times.
+   * @param data to transmit.
+   */
+  void write(uint16_t data, uint32_t n);
+
+  /**
+   * @brief Transmit multiple bytes/words.
+   * @param buffer Bytes/words to transmit.
+   * @param length Number of bytes/words in buffer to transmit.
+   */
+  void write(const void * buffer, uint32_t length);
+
+  /**
+   * @brief Transmit a byte, then return the next unread byte.
+   *
+   * This function transmits before receiving.
+   *
+   * @param data Byte to transmit.
+   * @return Next unread byte.
+   */
+  uint8_t transfer(uint8_t data) const;
+  uint16_t transfer16(uint16_t data) const;
+
+  /**
+   * @brief Sets up a DMA Transfer for "length" bytes.
+   * The transfer mode (8 or 16 bit mode) is evaluated from the SPI peripheral setting.
+   *
+   * This function transmits and receives to buffers.
+   *
+   * @param transmitBuf buffer Bytes to transmit. If passed as 0, it sends FF repeatedly for "length" bytes
+   * @param receiveBuf buffer Bytes to save received data.
+   * @param length Number of bytes in buffer to transmit.
+   */
+  uint8_t dmaTransfer(const void * transmitBuf, void * receiveBuf, uint16_t length);
+  void dmaTransferSet(const void *transmitBuf, void *receiveBuf);
+  uint8_t dmaTransferRepeat(uint16_t length);
+
+  /**
+   * @brief Sets up a DMA Transmit for SPI 8 or 16 bit transfer mode.
+   * The transfer mode (8 or 16 bit mode) is evaluated from the SPI peripheral setting.
+   *
+   * This function only transmits and does not care about the RX fifo.
+   *
+   * @param data buffer half words to transmit,
+   * @param length Number of bytes in buffer to transmit.
+   * @param minc Set to use Memory Increment mode, clear to use Circular mode.
+   */
+  uint8_t dmaSend(const void * transmitBuf, uint16_t length, bool minc = 1);
+  void dmaSendSet(const void * transmitBuf, bool minc);
+  uint8_t dmaSendRepeat(uint16_t length);
+
+  uint8_t dmaSendAsync(const void * transmitBuf, uint16_t length, bool minc = 1);
+  /*
+   * Pin accessors
+   */
+
+  /**
+   * @brief Return the number of the MISO (master in, slave out) pin
+   */
+  uint8_t misoPin();
+
+  /**
+   * @brief Return the number of the MOSI (master out, slave in) pin
+   */
+  uint8_t mosiPin();
+
+  /**
+   * @brief Return the number of the SCK (serial clock) pin
+   */
+  uint8_t sckPin();
+
+  /**
+   * @brief Return the number of the NSS (slave select) pin
+   */
+  uint8_t nssPin();
+
+  /* Escape hatch */
+
+  /**
+   * @brief Get a pointer to the underlying libmaple spi_dev for
+   *        this HardwareSPI instance.
+   */
+  spi_dev* c_dev(void) { return _currentSetting->spi_d; }
+
+  spi_dev* dev() { return _currentSetting->spi_d; }
+
+  /**
+   * @brief Sets the number of the SPI peripheral to be used by
+   *        this HardwareSPI instance.
+   *
+   * @param spi_num Number of the SPI port. 1-2 in low density devices
+   *     or 1-3 in high density devices.
+   */
+  void setModule(int spi_num) {
+    _currentSetting=&_settings[spi_num-1];// SPI channels are called 1 2 and 3 but the array is zero indexed
+  }
+
+  /* -- The following methods are deprecated --------------------------- */
+
+  /**
+   * @brief Deprecated.
+   *
+   * Use HardwareSPI::transfer() instead.
+   *
+   * @see HardwareSPI::transfer()
+   */
+  uint8_t send(uint8_t data);
+
+  /**
+   * @brief Deprecated.
+   *
+   * Use HardwareSPI::write() in combination with
+   * HardwareSPI::read() (or HardwareSPI::transfer()) instead.
+   *
+   * @see HardwareSPI::write()
+   * @see HardwareSPI::read()
+   * @see HardwareSPI::transfer()
+   */
+  uint8_t send(uint8_t *data, uint32_t length);
+
+  /**
+   * @brief Deprecated.
+   *
+   * Use HardwareSPI::read() instead.
+   *
+   * @see HardwareSPI::read()
+   */
+  uint8_t recv();
+
+private:
+
+  SPISettings _settings[BOARD_NR_SPI];
+  SPISettings *_currentSetting;
+
+  void updateSettings();
+
+  /*
+   * Functions added for DMA transfers with Callback.
+   * Experimental.
+   */
+
+  void EventCallback();
+
+  #if BOARD_NR_SPI >= 1
+    static void _spi1EventCallback();
+  #endif
+  #if BOARD_NR_SPI >= 2
+    static void _spi2EventCallback();
+  #endif
+  #if BOARD_NR_SPI >= 3
+    static void _spi3EventCallback();
+  #endif
+  /*
+  spi_dev *spi_d;
+  uint8_t _SSPin;
+  uint32_t clockDivider;
+  uint8_t dataMode;
+  BitOrder bitOrder;
+  */
+};
+
+extern SPIClass SPI;

platformio.ini

@@ -265,7 +265,7 @@ build_flags   = !python Marlin/src/HAL/HAL_STM32F1/STM32F1_flag_script.py
   -DDEBUG_LEVEL=0
 build_unflags = -std=gnu++11
 lib_deps      = ${common.lib_deps}
-lib_ignore    = U8glib-HAL, Adafruit NeoPixel
+lib_ignore    = U8glib-HAL, Adafruit NeoPixel, SPI
 src_filter    = ${common.default_src_filter} +<src/HAL/HAL_STM32F1>
 monitor_speed = 250000
 
@@ -285,7 +285,7 @@ build_flags       = !python Marlin/src/HAL/HAL_STM32F1/STM32F1_flag_script.py
 build_unflags     = -std=gnu++11
 lib_deps          = ${common.lib_deps}
   SoftwareSerialM=https://github.com/FYSETC/SoftwareSerialM/archive/master.zip
-lib_ignore        = Adafruit NeoPixel
+lib_ignore        = Adafruit NeoPixel, SPI
 lib_ldf_mode      = chain
 src_filter        = ${common.default_src_filter} +<src/HAL/HAL_STM32F1>
 monitor_speed     = 250000
@@ -306,7 +306,7 @@ build_flags       = !python Marlin/src/HAL/HAL_STM32F1/STM32F1_flag_script.py
   -DDEBUG_LEVEL=0
 build_unflags     = -std=gnu++11
 lib_deps          = ${common.lib_deps}
-lib_ignore        = Adafruit NeoPixel
+lib_ignore        = Adafruit NeoPixel, SPI
 src_filter        = ${common.default_src_filter} +<src/HAL/HAL_STM32F1>
 monitor_speed     = 115200
 upload_protocol   = stlink
@@ -366,7 +366,7 @@ build_flags   = !python Marlin/src/HAL/HAL_STM32F1/STM32F1_flag_script.py
 build_unflags = -std=gnu++11 -DCONFIG_MAPLE_MINI_NO_DISABLE_DEBUG=1
 src_filter    = ${common.default_src_filter} +<src/HAL/HAL_STM32F1>
 lib_deps      = ${common.lib_deps}
-lib_ignore    = Adafruit NeoPixel
+lib_ignore    = Adafruit NeoPixel, SPI
 
 #
 # MKS Robin (STM32F103ZET6)
@@ -381,7 +381,7 @@ build_flags   = !python Marlin/src/HAL/HAL_STM32F1/STM32F1_flag_script.py
 build_unflags = -std=gnu++11
 src_filter    = ${common.default_src_filter} +<src/HAL/HAL_STM32F1>
 lib_deps      = ${common.lib_deps}
-lib_ignore    = Adafruit NeoPixel
+lib_ignore    = Adafruit NeoPixel, SPI
 
 #
 # MKS ROBIN LITE/LITE2 (STM32F103RCT6)
@@ -396,7 +396,7 @@ build_flags   = !python Marlin/src/HAL/HAL_STM32F1/STM32F1_flag_script.py
 build_unflags = -std=gnu++11
 src_filter    = ${common.default_src_filter} +<src/HAL/HAL_STM32F1>
 lib_deps      = ${common.lib_deps}
-lib_ignore    = Adafruit NeoPixel
+lib_ignore    = Adafruit NeoPixel, SPI
 
 #
 # MKS Robin Mini (STM32F103VET6)
@@ -411,7 +411,7 @@ build_flags   = !python Marlin/src/HAL/HAL_STM32F1/STM32F1_flag_script.py
 build_unflags = -std=gnu++11
 src_filter    = ${common.default_src_filter} +<src/HAL/HAL_STM32F1>
 lib_deps      = ${common.lib_deps}
-lib_ignore    = Adafruit NeoPixel
+lib_ignore    = Adafruit NeoPixel, SPI
 
 #
 # MKS Robin Nano (STM32F103VET6)
@@ -426,7 +426,7 @@ build_flags   = !python Marlin/src/HAL/HAL_STM32F1/STM32F1_flag_script.py
 build_unflags = -std=gnu++11
 src_filter    = ${common.default_src_filter} +<src/HAL/HAL_STM32F1>
 lib_deps      = ${common.lib_deps}
-lib_ignore    = Adafruit NeoPixel
+lib_ignore    = Adafruit NeoPixel, SPI
 
 #
 # JGAurora A5S A1 (STM32F103ZET6)
@@ -441,7 +441,7 @@ build_flags   = !python Marlin/src/HAL/HAL_STM32F1/STM32F1_flag_script.py
 build_unflags = -std=gnu++11
 src_filter    = ${common.default_src_filter} +<src/HAL/HAL_STM32F1>
 lib_deps      = ${common.lib_deps}
-lib_ignore    = Adafruit NeoPixel
+lib_ignore    = Adafruit NeoPixel, SPI
 monitor_speed = 250000
 
 #
@@ -536,7 +536,7 @@ build_flags = !python Marlin/src/HAL/HAL_STM32F1/STM32F1_flag_script.py -DMCU_ST
   -DDEBUG_LEVEL=0
 src_filter  = ${common.default_src_filter} +<src/HAL/HAL_STM32F1>
 #-<frameworks>
-lib_ignore  = Adafruit NeoPixel, LiquidCrystal, LiquidTWI2, TMCStepper, U8glib-HAL
+lib_ignore  = Adafruit NeoPixel, LiquidCrystal, LiquidTWI2, TMCStepper, U8glib-HAL, SPI
 
 #
 # Espressif ESP32