/**
* \brief Initialize SPI as master.
*/
static void spi_master_initialize(void)
{
/* Configure an SPI peripheral. */
uint32_t spi_chip_sel, spi_clk_freq, spi_clk_pol, spi_clk_pha;
spi_enable_clock(SPI_MASTER_BASE);
spi_reset(SPI_MASTER_BASE);
spi_set_master_mode(SPI_MASTER_BASE);
spi_disable_mode_fault_detect(SPI_MASTER_BASE);
spi_disable_loopback(SPI_MASTER_BASE);
spi_set_peripheral_chip_select_value(SPI_MASTER_BASE, spi_get_pcs(2)); // This sets the value of PCS within the Mode Register.
spi_set_variable_peripheral_select(SPI_MASTER_BASE); // PCS needs to be set within each transfer (PCS within SPI_TDR).
spi_disable_peripheral_select_decode(SPI_MASTER_BASE); // Each CS is to be connected to a single device.
spi_set_delay_between_chip_select(SPI_MASTER_BASE, SPI_DLYBCS);
/* Set communication parameters for CS0 */
spi_chip_sel = 0;
spi_clk_freq = 100000; // SPI CLK for RTC = 100kHz.
spi_clk_pol = 1;
spi_clk_pha = 0;
spi_set_transfer_delay(SPI_MASTER_BASE, spi_chip_sel, SPI_DLYBS,
SPI_DLYBCT);
spi_set_bits_per_transfer(SPI_MASTER_BASE, spi_chip_sel, SPI_CSR_BITS_16_BIT);
spi_set_baudrate_div(SPI_MASTER_BASE, spi_chip_sel, spi_calc_baudrate_div(spi_clk_freq, sysclk_get_cpu_hz()));
spi_configure_cs_behavior(SPI_MASTER_BASE, spi_chip_sel, SPI_CS_RISE_FORCED); // CS rises after SPI transfers have completed.
spi_set_clock_polarity(SPI_MASTER_BASE, spi_chip_sel, spi_clk_pol);
spi_set_clock_phase(SPI_MASTER_BASE, spi_chip_sel, spi_clk_pha);
/* Set communication parameters for CS1 */
spi_chip_sel = 1;
spi_clk_freq = 2000000; // SPI CLK for RTC = 4MHz.
spi_clk_pol = 0;
spi_clk_pha = 0;
spi_set_transfer_delay(SPI_MASTER_BASE, spi_chip_sel, SPI_DLYBS,
SPI_DLYBCT);
spi_set_bits_per_transfer(SPI_MASTER_BASE, spi_chip_sel, SPI_CSR_BITS_8_BIT);
spi_set_baudrate_div(SPI_MASTER_BASE, spi_chip_sel, spi_calc_baudrate_div(spi_clk_freq, sysclk_get_cpu_hz()));
spi_configure_cs_behavior(SPI_MASTER_BASE, spi_chip_sel, SPI_CS_RISE_FORCED);
spi_set_clock_polarity(SPI_MASTER_BASE, spi_chip_sel, spi_clk_pol);
spi_set_clock_phase(SPI_MASTER_BASE, spi_chip_sel, spi_clk_pha);
/* Set communication parameters for CS2 */
spi_chip_sel = 2;
spi_clk_freq = 44000000; // SPI CLK for MEM2 = 44MHz.
spi_clk_pol = 1;
spi_clk_pha = 0;
spi_set_transfer_delay(SPI_MASTER_BASE, spi_chip_sel, SPI_DLYBS,
SPI_DLYBCT);
spi_set_bits_per_transfer(SPI_MASTER_BASE, spi_chip_sel, SPI_CSR_BITS_8_BIT);
spi_set_baudrate_div(SPI_MASTER_BASE, spi_chip_sel, spi_calc_baudrate_div(spi_clk_freq, sysclk_get_cpu_hz()));
spi_configure_cs_behavior(SPI_MASTER_BASE, spi_chip_sel, SPI_CS_KEEP_LOW);
spi_set_clock_polarity(SPI_MASTER_BASE, spi_chip_sel, spi_clk_pol);
spi_set_clock_phase(SPI_MASTER_BASE, spi_chip_sel, spi_clk_pha);
/* Enable SPI Communication */
spi_enable(SPI_MASTER_BASE);
}
/** \brief Initialize the SPI in master mode.
*
* \param p_spi Base address of the SPI instance.
*
*/
void spi_master_init(Spi *p_spi)
{
spi_enable_clock(p_spi);
spi_reset(p_spi);
spi_set_master_mode(p_spi);
spi_disable_mode_fault_detect(p_spi);
spi_disable_loopback(p_spi);
spi_set_peripheral_chip_select_value(p_spi, DEFAULT_CHIP_ID);
spi_set_fixed_peripheral_select(p_spi);
spi_disable_peripheral_select_decode(p_spi);
spi_set_delay_between_chip_select(p_spi, CONFIG_SPI_MASTER_DELAY_BCS);
}
spi_p spi_new_instance(Spi * spi_base, uint8_t spi_chip_sel, uint32_t spi_freq, uint8_t spi_mode, uint8_t buffer_size, void(*handler_call_back )(spi_p, uint8_t))
{
_spi_base = spi_base;
if (!spi_is_enabled(_spi_base)) {
_spi_init_base(spi_base);
}
spi_p _spi = malloc(sizeof *_spi);
_spi->_call_back = handler_call_back;
_spi->_cs_pin = spi_chip_sel;
_spi->_spi_rx_fifo_desc = (fifo_desc_t *)malloc(sizeof(fifo_desc_t));
_spi->_spi_tx_fifo_desc = (fifo_desc_t *)malloc(sizeof(fifo_desc_t));
union spi_buffer_element *spi_tx_fifo_buffer = (union spi_buffer_element *)(malloc(sizeof(union spi_buffer_element) * buffer_size));
union spi_buffer_element *spi_rx_fifo_buffer = (union spi_buffer_element *)(malloc(sizeof(union spi_buffer_element) * buffer_size));
fifo_init(_spi->_spi_rx_fifo_desc, spi_rx_fifo_buffer, buffer_size);
fifo_init(_spi->_spi_tx_fifo_desc, spi_tx_fifo_buffer, buffer_size);
spi_set_peripheral_chip_select_value(spi_base, spi_get_pcs(spi_chip_sel));
switch (spi_mode)
{
case 0:
spi_set_clock_polarity(spi_base, spi_chip_sel,0);
spi_set_clock_phase(spi_base, spi_chip_sel, 1);
break;
case 1:
spi_set_clock_polarity(spi_base, spi_chip_sel, 0);
spi_set_clock_phase(spi_base, spi_chip_sel, 0);
break;
case 2:
spi_set_clock_polarity(spi_base, spi_chip_sel, 1);
spi_set_clock_phase(spi_base, spi_chip_sel, 1);
break;
case 3:
spi_set_clock_polarity(spi_base, spi_chip_sel, 1);
spi_set_clock_phase(spi_base, spi_chip_sel, 0);
break;
}
spi_set_bits_per_transfer(spi_base, spi_chip_sel, SPI_CSR_BITS_8_BIT);
spi_configure_cs_behavior(spi_base, spi_chip_sel, SPI_CS_KEEP_LOW);
spi_set_baudrate_div(spi_base, spi_chip_sel, (sysclk_get_peripheral_hz() / spi_freq));
spi_set_delay_between_chip_select(spi_base, 0x10);
spi_set_transfer_delay(spi_base, spi_chip_sel, 0x01, 0x10);
spi_enable(spi_base);
return _spi;
}
/** \brief Initialize the SPI in master mode.
*
* \param p_spi Base address of the SPI instance.
*
*/
void spi_master_init(Spi *p_spi)
{
#if SAMG55
flexcom_enable(BOARD_FLEXCOM_SPI);
flexcom_set_opmode(BOARD_FLEXCOM_SPI, FLEXCOM_SPI);
#else
spi_enable_clock(p_spi);
#endif
spi_reset(p_spi);
spi_set_master_mode(p_spi);
spi_disable_mode_fault_detect(p_spi);
spi_disable_loopback(p_spi);
spi_set_peripheral_chip_select_value(p_spi, DEFAULT_CHIP_ID);
spi_set_fixed_peripheral_select(p_spi);
spi_disable_peripheral_select_decode(p_spi);
spi_set_delay_between_chip_select(p_spi, CONFIG_SPI_MASTER_DELAY_BCS);
}
