/**
* @brief Initializes the SPIx peripheral according to the specified
* parameters in the I2S_InitStruct.
* @param SPIx: where x can be 1 to select the SPI peripheral (configured in I2S mode).
* @param I2S_InitStruct: pointer to an I2S_InitTypeDef structure that
* contains the configuration information for the specified SPI peripheral
* configured in I2S mode.
* @note This function calculates the optimal prescaler needed to obtain the most
* accurate audio frequency (depending on the I2S clock source, the PLL values
* and the product configuration). But in case the prescaler value is greater
* than 511, the default value (0x02) will be configured instead.
* @retval None
*/
void I2S_Init(SPI_TypeDef* SPIx, I2S_InitTypeDef* I2S_InitStruct)
{
uint16_t tmpreg = 0, i2sdiv = 2, i2sodd = 0, packetlength = 1;
uint32_t tmp = 0;
RCC_ClocksTypeDef RCC_Clocks;
uint32_t sourceclock = 0;
/* Check the I2S parameters */
assert_param(IS_SPI_1_PERIPH(SPIx));
assert_param(IS_I2S_MODE(I2S_InitStruct->I2S_Mode));
assert_param(IS_I2S_STANDARD(I2S_InitStruct->I2S_Standard));
assert_param(IS_I2S_DATA_FORMAT(I2S_InitStruct->I2S_DataFormat));
assert_param(IS_I2S_MCLK_OUTPUT(I2S_InitStruct->I2S_MCLKOutput));
assert_param(IS_I2S_AUDIO_FREQ(I2S_InitStruct->I2S_AudioFreq));
assert_param(IS_I2S_CPOL(I2S_InitStruct->I2S_CPOL));
/*----------------------- SPIx I2SCFGR & I2SPR Configuration -----------------*/
/* Clear I2SMOD, I2SE, I2SCFG, PCMSYNC, I2SSTD, CKPOL, DATLEN and CHLEN bits */
SPIx->I2SCFGR &= I2SCFGR_CLEAR_Mask;
SPIx->I2SPR = 0x0002;
/* Get the I2SCFGR register value */
tmpreg = SPIx->I2SCFGR;
/* If the default value has to be written, reinitialize i2sdiv and i2sodd*/
if(I2S_InitStruct->I2S_AudioFreq == I2S_AudioFreq_Default)
{
i2sodd = (uint16_t)0;
i2sdiv = (uint16_t)2;
}
/* If the requested audio frequency is not the default, compute the prescaler */
else
{
/* Check the frame length (For the Prescaler computing) */
if(I2S_InitStruct->I2S_DataFormat == I2S_DataFormat_16b)
{
/* Packet length is 16 bits */
packetlength = 1;
}
else
{
/* Packet length is 32 bits */
packetlength = 2;
}
/* I2S Clock source is System clock: Get System Clock frequency */
RCC_GetClocksFreq(&RCC_Clocks);
/* Get the source clock value: based on System Clock value */
sourceclock = RCC_Clocks.SYSCLK_Frequency;
/* Compute the Real divider depending on the MCLK output state with a floating point */
if(I2S_InitStruct->I2S_MCLKOutput == I2S_MCLKOutput_Enable)
{
/* MCLK output is enabled */
tmp = (uint16_t)(((((sourceclock / 256) * 10) / I2S_InitStruct->I2S_AudioFreq)) + 5);
}
else
{
/* MCLK output is disabled */
tmp = (uint16_t)(((((sourceclock / (32 * packetlength)) *10 ) / I2S_InitStruct->I2S_AudioFreq)) + 5);
}
/* Remove the floating point */
tmp = tmp / 10;
/* Check the parity of the divider */
i2sodd = (uint16_t)(tmp & (uint16_t)0x0001);
/* Compute the i2sdiv prescaler */
i2sdiv = (uint16_t)((tmp - i2sodd) / 2);
/* Get the Mask for the Odd bit (SPI_I2SPR[8]) register */
i2sodd = (uint16_t) (i2sodd << 8);
}
/* Test if the divider is 1 or 0 or greater than 0xFF */
if ((i2sdiv < 2) || (i2sdiv > 0xFF))
{
/* Set the default values */
i2sdiv = 2;
i2sodd = 0;
}
/* Write to SPIx I2SPR register the computed value */
SPIx->I2SPR = (uint16_t)(i2sdiv | (uint16_t)(i2sodd | (uint16_t)I2S_InitStruct->I2S_MCLKOutput));
/* Configure the I2S with the SPI_InitStruct values */
tmpreg |= (uint16_t)(SPI_I2SCFGR_I2SMOD | (uint16_t)(I2S_InitStruct->I2S_Mode | \
(uint16_t)(I2S_InitStruct->I2S_Standard | (uint16_t)(I2S_InitStruct->I2S_DataFormat | \
(uint16_t)I2S_InitStruct->I2S_CPOL))));
/* Write to SPIx I2SCFGR */
SPIx->I2SCFGR = tmpreg;
}
/**
* @brief Initializes the SPIx peripheral according to the specified
* parameters in the I2S_InitStruct.
* @param SPIx: where x can be 2 or 3 to select the SPI peripheral
* (configured in I2S mode).
* @param I2S_InitStruct: pointer to an I2S_InitTypeDef structure that
* contains the configuration information for the specified SPI peripheral
* configured in I2S mode.
* @note
* The function calculates the optimal prescaler needed to obtain the most
* accurate audio frequency (depending on the I2S clock source, the PLL values
* and the product configuration). But in case the prescaler value is greater
* than 511, the default value (0x02) will be configured instead. *
* @retval None
*/
void I2S_Init(SPI_TypeDef* SPIx, I2S_InitTypeDef* I2S_InitStruct)
{
uint16_t tmpreg = 0, i2sdiv = 2, i2sodd = 0, packetlength = 1;
uint32_t tmp = 0;
RCC_ClocksTypeDef RCC_Clocks;
uint32_t sourceclock = 0;
/* Check the I2S parameters */
assert_param(IS_SPI_23_PERIPH(SPIx));
assert_param(IS_I2S_MODE(I2S_InitStruct->I2S_Mode));
assert_param(IS_I2S_STANDARD(I2S_InitStruct->I2S_Standard));
assert_param(IS_I2S_DATA_FORMAT(I2S_InitStruct->I2S_DataFormat));
assert_param(IS_I2S_MCLK_OUTPUT(I2S_InitStruct->I2S_MCLKOutput));
assert_param(IS_I2S_AUDIO_FREQ(I2S_InitStruct->I2S_AudioFreq));
assert_param(IS_I2S_CPOL(I2S_InitStruct->I2S_CPOL));
/*----------------------- SPIx I2SCFGR & I2SPR Configuration -----------------*/
/* Clear I2SMOD, I2SE, I2SCFG, PCMSYNC, I2SSTD, CKPOL, DATLEN and CHLEN bits */
SPIx->I2SCFGR &= I2SCFGR_CLEAR_Mask;
SPIx->I2SPR = 0x0002;
/* Get the I2SCFGR register value */
tmpreg = SPIx->I2SCFGR;
/* If the default value has to be written, reinitialize i2sdiv and i2sodd*/
if(I2S_InitStruct->I2S_AudioFreq == I2S_AudioFreq_Default)
{
i2sodd = (uint16_t)0;
i2sdiv = (uint16_t)2;
}
/* If the requested audio frequency is not the default, compute the prescaler */
else
{
/* Check the frame length (For the Prescaler computing) */
if(I2S_InitStruct->I2S_DataFormat == I2S_DataFormat_16b)
{
/* Packet length is 16 bits */
packetlength = 1;
}
else
{
/* Packet length is 32 bits */
packetlength = 2;
}
/* Get the I2S clock source mask depending on the peripheral number */
if(((uint32_t)SPIx) == SPI2_BASE)
{
/* The mask is relative to I2S2 */
tmp = I2S2_CLOCK_SRC;
}
else
{
/* The mask is relative to I2S3 */
tmp = I2S3_CLOCK_SRC;
}
/* Check the I2S clock source configuration depending on the Device:
Only Connectivity line devices have the PLL3 VCO clock */
#ifdef STM32F10X_CL
if((RCC->CFGR2 & tmp) != 0)
{
/* Get the configuration bits of RCC PLL3 multiplier */
tmp = (uint32_t)((RCC->CFGR2 & I2S_MUL_MASK) >> 12);
/* Get the value of the PLL3 multiplier */
if((tmp > 5) && (tmp < 15))
{
/* Multplier is between 8 and 14 (value 15 is forbidden) */
tmp += 2;
}
else
{
if (tmp == 15)
{
/* Multiplier is 20 */
tmp = 20;
}
}
/* Get the PREDIV2 value */
sourceclock = (uint32_t)(((RCC->CFGR2 & I2S_DIV_MASK) >> 4) + 1);
/* Calculate the Source Clock frequency based on PLL3 and PREDIV2 values */
sourceclock = (uint32_t) ((HSE_Value / sourceclock) * tmp * 2);
}
else
{
/**
* @brief Initializes the I2S according to the specified parameters
* in the I2S_InitTypeDef and create the associated handle.
* @param hi2s: pointer to a I2S_HandleTypeDef structure that contains
* the configuration information for I2S module
* @retval HAL status
*/
HAL_StatusTypeDef HAL_I2S_Init(I2S_HandleTypeDef *hi2s)
{
uint32_t i2sdiv = 2, i2sodd = 0, packetlength = 1;
uint32_t tmp = 0, i2sclk = 0, tmpreg = 0;
/* Check the I2S handle allocation */
if(hi2s == NULL)
{
return HAL_ERROR;
}
/* Check the I2S parameters */
assert_param(IS_I2S_ALL_INSTANCE(hi2s->Instance));
assert_param(IS_I2S_MODE(hi2s->Init.Mode));
assert_param(IS_I2S_STANDARD(hi2s->Init.Standard));
assert_param(IS_I2S_DATA_FORMAT(hi2s->Init.DataFormat));
assert_param(IS_I2S_MCLK_OUTPUT(hi2s->Init.MCLKOutput));
assert_param(IS_I2S_AUDIO_FREQ(hi2s->Init.AudioFreq));
assert_param(IS_I2S_CPOL(hi2s->Init.CPOL));
if(hi2s->State == HAL_I2S_STATE_RESET)
{
/* Allocate lock resource and initialize it */
hi2s->Lock = HAL_UNLOCKED;
/* Init the low level hardware : GPIO, CLOCK, CORTEX...etc */
HAL_I2S_MspInit(hi2s);
}
hi2s->State = HAL_I2S_STATE_BUSY;
/* If the default value has to be written, reinitialize i2sdiv and i2sodd*/
if(hi2s->Init.AudioFreq == I2S_AUDIOFREQ_DEFAULT)
{
i2sodd = (uint32_t)0;
i2sdiv = (uint32_t)2;
}
/* If the requested audio frequency is not the default, compute the prescaler */
else
{
/* Check the frame length (For the Prescaler computing) *******************/
if(hi2s->Init.DataFormat == I2S_DATAFORMAT_16B)
{
/* Packet length is 16 bits */
packetlength = 1;
}
else
{
/* Packet length is 32 bits */
packetlength = 2;
}
/* Get the source clock value: based on System Clock value */
i2sclk = HAL_RCC_GetSysClockFreq();
/* Compute the Real divider depending on the MCLK output state, with a floating point */
if(hi2s->Init.MCLKOutput == I2S_MCLKOUTPUT_ENABLE)
{
/* MCLK output is enabled */
tmp = (uint32_t)(((((i2sclk / 256) * 10) / hi2s->Init.AudioFreq)) + 5);
}
else
{
/* MCLK output is disabled */
tmp = (uint32_t)(((((i2sclk / (32 * packetlength)) *10 ) / hi2s->Init.AudioFreq)) + 5);
}
/* Remove the flatting point */
tmp = tmp / 10;
/* Check the parity of the divider */
i2sodd = (uint32_t)(tmp & (uint32_t)1);
/* Compute the i2sdiv prescaler */
i2sdiv = (uint32_t)((tmp - i2sodd) / 2);
/* Get the Mask for the Odd bit (SPI_I2SPR[8]) register */
i2sodd = (uint32_t) (i2sodd << 8);
}
/* Test if the divider is 1 or 0 or greater than 0xFF */
if((i2sdiv < 2) || (i2sdiv > 0xFF))
{
/* Set the default values */
i2sdiv = 2;
i2sodd = 0;
}
/*----------------------- SPIx I2SCFGR & I2SPR Configuration ----------------*/
/* Write to SPIx I2SPR register the computed value */
hi2s->Instance->I2SPR = (uint32_t)((uint32_t)i2sdiv | (uint32_t)(i2sodd | (uint32_t)hi2s->Init.MCLKOutput));
/* Clear I2SMOD, I2SE, I2SCFG, PCMSYNC, I2SSTD, CKPOL, DATLEN and CHLEN bits */
/* And configure the I2S with the I2S_InitStruct values */
MODIFY_REG( hi2s->Instance->I2SCFGR, (SPI_I2SCFGR_CHLEN | SPI_I2SCFGR_DATLEN |\
SPI_I2SCFGR_CKPOL | SPI_I2SCFGR_I2SSTD |\
SPI_I2SCFGR_PCMSYNC | SPI_I2SCFGR_I2SCFG |\
SPI_I2SCFGR_I2SE | SPI_I2SCFGR_I2SMOD),\
(SPI_I2SCFGR_I2SMOD | hi2s->Init.Mode |\
hi2s->Init.Standard | hi2s->Init.DataFormat |\
hi2s->Init.CPOL));
/* Get the I2SCFGR register value */
tmpreg = hi2s->Instance->I2SCFGR;
#if defined(SPI_I2SCFGR_ASTRTEN)
if (hi2s->Init.Standard == I2S_STANDARD_PCM_SHORT)
{
/* Write to SPIx I2SCFGR */
hi2s->Instance->I2SCFGR = tmpreg | SPI_I2SCFGR_ASTRTEN;
}
else
{
/* Write to SPIx I2SCFGR */
hi2s->Instance->I2SCFGR = tmpreg;
}
#else
/* Write to SPIx I2SCFGR */
hi2s->Instance->I2SCFGR = tmpreg;
#endif
hi2s->ErrorCode = HAL_I2S_ERROR_NONE;
hi2s->State= HAL_I2S_STATE_READY;
return HAL_OK;
}
