/*!
\brief I2S parameter configuration
\param[in] spi_periph: SPIx(x=0,1,2,3,4)
\param[in] i2s_mode:
\arg I2S_MODE_SLAVETX : I2S slave transmit mode
\arg I2S_MODE_SLAVERX : I2S slave receive mode
\arg I2S_MODE_MASTERTX : I2S master transmit mode
\arg I2S_MODE_MASTERRX : I2S master receive mode
\param[in] i2s_std:
\arg I2S_STD_PHILLIPS : I2S phillips standard
\arg I2S_STD_MSB : I2S MSB standard
\arg I2S_STD_LSB : I2S LSB standard
\arg I2S_STD_PCMSHORT : I2S PCM short standard
\arg I2S_STD_PCMLONG : I2S PCM long standard
\param[in] i2s_ckpl:
\arg I2S_CKPL_LOW : I2S clock polarity low level
\arg I2S_CKPL_HIGH : I2S clock polarity high level
\param[out] none
\retval none
*/
void i2s_init(uint32_t spi_periph, uint32_t i2s_mode, uint32_t i2s_standard, uint32_t i2s_ckpl)
{
uint32_t reg= 0U;
reg = SPI_I2SCTL(spi_periph);
reg &= I2S_INIT_MASK;
/* enable I2S mode */
reg |= (uint32_t)SPI_I2SCTL_I2SSEL;
/* select I2S mode */
reg |= (uint32_t)i2s_mode;
/* select I2S standard */
reg |= (uint32_t)i2s_standard;
/* select I2S polarity */
reg |= (uint32_t)i2s_ckpl;
/* write to SPI_I2SCTL register */
SPI_I2SCTL(spi_periph) = (uint32_t)reg;
}
/*!
\brief disable I2S
\param[in] spi_periph: SPIx(x=1,2)
\param[out] none
\retval none
*/
void i2s_disable(uint32_t spi_periph)
{
SPI_I2SCTL(spi_periph) &= (uint32_t)(~SPI_I2SCTL_I2SEN);
}
/*!
\brief enable I2S
\param[in] spi_periph: SPIx(x=1,2)
\param[out] none
\retval none
*/
void i2s_enable(uint32_t spi_periph)
{
SPI_I2SCTL(spi_periph) |= (uint32_t)SPI_I2SCTL_I2SEN;
}
/*!
\brief configure I2S prescale
\param[in] spi_periph: SPIx(x=1,2)
\param[in] i2s_audiosample: I2S audio sample rate
only one parameter can be selected which is shown as below:
\arg I2S_AUDIOSAMPLE_8K: audio sample rate is 8KHz
\arg I2S_AUDIOSAMPLE_11K: audio sample rate is 11KHz
\arg I2S_AUDIOSAMPLE_16K: audio sample rate is 16KHz
\arg I2S_AUDIOSAMPLE_22K: audio sample rate is 22KHz
\arg I2S_AUDIOSAMPLE_32K: audio sample rate is 32KHz
\arg I2S_AUDIOSAMPLE_44K: audio sample rate is 44KHz
\arg I2S_AUDIOSAMPLE_48K: audio sample rate is 48KHz
\arg I2S_AUDIOSAMPLE_96K: audio sample rate is 96KHz
\arg I2S_AUDIOSAMPLE_192K: audio sample rate is 192KHz
\param[in] i2s_frameformat: I2S data length and channel length
only one parameter can be selected which is shown as below:
\arg I2S_FRAMEFORMAT_DT16B_CH16B: I2S data length is 16 bit and channel length is 16 bit
\arg I2S_FRAMEFORMAT_DT16B_CH32B: I2S data length is 16 bit and channel length is 32 bit
\arg I2S_FRAMEFORMAT_DT24B_CH32B: I2S data length is 24 bit and channel length is 32 bit
\arg I2S_FRAMEFORMAT_DT32B_CH32B: I2S data length is 32 bit and channel length is 32 bit
\param[in] i2s_mckout: I2S master clock output
only one parameter can be selected which is shown as below:
\arg I2S_MCKOUT_ENABLE: I2S master clock output enable
\arg I2S_MCKOUT_DISABLE: I2S master clock output disable
\param[out] none
\retval none
*/
void i2s_psc_config(uint32_t spi_periph, uint32_t i2s_audiosample, uint32_t i2s_frameformat, uint32_t i2s_mckout)
{
uint32_t i2sdiv = 2U, i2sof = 0U;
uint32_t clks = 0U;
uint32_t i2sclock = 0U;
#ifndef I2S_EXTERNAL_CLOCK_IN
uint32_t plli2sm = 0U, plli2sn = 0U, plli2sr = 0U;
#endif /* I2S_EXTERNAL_CLOCK_IN */
/* deinit SPI_I2SPSC register */
SPI_I2SPSC(spi_periph) = SPI_I2SPSC_DEFAULT_VALUE;
#ifdef I2S_EXTERNAL_CLOCK_IN
rcu_i2s_clock_config(RCU_I2SSRC_I2S_CKIN);
/* set the I2S clock to the external clock input value */
i2sclock = I2S_EXTERNAL_CLOCK_IN;
#else
/* turn on the oscillator HXTAL */
rcu_osci_on(RCU_HXTAL);
/* wait for oscillator stabilization flags is SET */
rcu_osci_stab_wait(RCU_HXTAL);
/* turn on the PLLI2S */
rcu_osci_on(RCU_PLLI2S_CK);
/* wait for PLLI2S flags is SET */
rcu_osci_stab_wait(RCU_PLLI2S_CK);
/* configure the I2S clock source selection */
rcu_i2s_clock_config(RCU_I2SSRC_PLLI2S);
/* get the RCU_PLL_PLLPSC value */
plli2sm = (uint32_t)(RCU_PLL & RCU_PLL_PLLPSC);
/* get the RCU_PLLI2S_PLLI2SN value */
plli2sn = (uint32_t)((RCU_PLLI2S & RCU_PLLI2S_PLLI2SN) >> 6);
/* get the RCU_PLLI2S_PLLI2SR value */
plli2sr = (uint32_t)((RCU_PLLI2S & RCU_PLLI2S_PLLI2SR) >> 28);
if ((RCU_PLL & RCU_PLL_PLLSEL) == RCU_PLLSRC_HXTAL) {
/* get the I2S source clock value */
i2sclock = (uint32_t)(((HXTAL_VALUE / plli2sm) * plli2sn) / plli2sr);
} else {
/* get the I2S source clock value */
i2sclock = (uint32_t)(((IRC16M_VALUE / plli2sm) * plli2sn) / plli2sr);
}
#endif /* I2S_EXTERNAL_CLOCK_IN */
/* config the prescaler depending on the mclk output state, the frame format and audio sample rate */
if (I2S_MCKOUT_ENABLE == i2s_mckout) {
clks = (uint32_t)(((i2sclock / 256U) * 10U) / i2s_audiosample);
} else {
if (I2S_FRAMEFORMAT_DT16B_CH16B == i2s_frameformat) {
clks = (uint32_t)(((i2sclock / 32U) * 10U) / i2s_audiosample);
} else {
clks = (uint32_t)(((i2sclock / 64U) * 10U) / i2s_audiosample);
}
}
/* remove the floating point */
clks = (clks + 5U) / 10U;
i2sof = (clks & 0x00000001U);
i2sdiv = ((clks - i2sof) / 2U);
i2sof = (i2sof << 8U);
/* set the default values */
if ((i2sdiv < 2U) || (i2sdiv > 255U)) {
i2sdiv = 2U;
i2sof = 0U;
}
/* configure SPI_I2SPSC */
SPI_I2SPSC(spi_periph) = (uint32_t)(i2sdiv | i2sof | i2s_mckout);
/* clear SPI_I2SCTL_DTLEN and SPI_I2SCTL_CHLEN bits */
SPI_I2SCTL(spi_periph) &= (uint32_t)(~(SPI_I2SCTL_DTLEN | SPI_I2SCTL_CHLEN));
/* configure data frame format */
SPI_I2SCTL(spi_periph) |= (uint32_t)i2s_frameformat;
}
