host-aprom/NUC123/StdDriver/src/i2s.c
2024-06-29 21:17:34 +01:00

223 lines
7.3 KiB
C

/**************************************************************************//**
* @file i2s.c
* @version V3.0
* $Revision: 7 $
* $Date: 15/07/02 11:21a $
* @brief NUC123 series I2S driver source file
*
* @note
* SPDX-License-Identifier: Apache-2.0
* Copyright (C) 2014~2015 Nuvoton Technology Corp. All rights reserved.
*****************************************************************************/
#include <stdio.h>
#include "NUC123.h"
/** @addtogroup Standard_Driver Standard Driver
@{
*/
/** @addtogroup I2S_Driver I2S Driver
@{
*/
/** @addtogroup I2S_EXPORTED_FUNCTIONS I2S Exported Functions
@{
*/
/**
* @brief This function is used to get I2S source clock frequency.
* @param[in] i2s The pointer of the specified I2S module.
* @return I2S source clock frequency (Hz).
* @details Return the source clock frequency according to the setting of I2S_S (CLKSEL2[1:0]).
*/
static uint32_t I2S_GetSourceClockFreq(I2S_T *i2s)
{
uint32_t u32Freq, u32ClkSrcSel;
u32ClkSrcSel = CLK->CLKSEL2 & CLK_CLKSEL2_I2S_S_Msk;
switch(u32ClkSrcSel)
{
case CLK_CLKSEL2_I2S_S_HXT:
u32Freq = __HXT;
break;
case CLK_CLKSEL2_I2S_S_PLL:
u32Freq = CLK_GetPLLClockFreq();
break;
case CLK_CLKSEL2_I2S_S_HIRC:
u32Freq = __HIRC;
break;
case CLK_CLKSEL2_I2S_S_HCLK:
u32Freq = SystemCoreClock;
break;
default:
u32Freq = __HIRC;
break;
}
return u32Freq;
}
/**
* @brief This function configures some parameters of I2S interface for general purpose use.
* @param[in] i2s The pointer of the specified I2S module.
* @param[in] u32MasterSlave I2S operation mode. Valid values are:
* - \ref I2S_MODE_MASTER
* - \ref I2S_MODE_SLAVE
* @param[in] u32SampleRate Sample rate
* @param[in] u32WordWidth Data length. Valid values are:
* - \ref I2S_DATABIT_8
* - \ref I2S_DATABIT_16
* - \ref I2S_DATABIT_24
* - \ref I2S_DATABIT_32
* @param[in] u32Channels Audio format. Valid values are:
* - \ref I2S_MONO
* - \ref I2S_STEREO
* @param[in] u32DataFormat Data format. Valid values are:
* - \ref I2S_FORMAT_I2S
* - \ref I2S_FORMAT_MSB
* - \ref I2S_FORMAT_PCM_A
* - \ref I2S_FORMAT_PCM_B
* @return Real sample rate.
* @details This function will configure I2S controller according to the input parameters. Set TX and RX FIFO threshold to middle value.
* The actual sample rate may be different from the target sample rate. The real sample rate will be returned for reference.
* @note Both the TX and RX functions will be enabled.
*/
uint32_t I2S_Open(I2S_T *i2s, uint32_t u32MasterSlave, uint32_t u32SampleRate, uint32_t u32WordWidth, uint32_t u32Channels, uint32_t u32DataFormat)
{
uint32_t u32Divider;
uint32_t u32BitRate, u32SrcClk;
/* Reset I2S */
SYS->IPRSTC2 |= SYS_IPRSTC2_I2S_RST_Msk;
SYS->IPRSTC2 &= ~SYS_IPRSTC2_I2S_RST_Msk;
/* Configure I2S controller according to input parameters. */
i2s->CON = u32MasterSlave | u32WordWidth | u32Channels | u32DataFormat | I2S_FIFO_TX_LEVEL_WORD_4 | I2S_FIFO_RX_LEVEL_WORD_4;
/* Get I2S source clock frequency */
u32SrcClk = I2S_GetSourceClockFreq(i2s);
/* Calculate bit clock rate */
u32BitRate = u32SampleRate * (((u32WordWidth >> 4) & 0x3) + 1) * 16;
u32Divider = ((u32SrcClk / u32BitRate) >> 1) - 1;
i2s->CLKDIV = (i2s->CLKDIV & ~I2S_CLKDIV_BCLK_DIV_Msk) | (u32Divider << 8);
/* Calculate real sample rate */
u32BitRate = u32SrcClk / ((u32Divider + 1) * 2);
u32SampleRate = u32BitRate / ((((u32WordWidth >> 4) & 0x3) + 1) * 16);
/* Enable TX, RX and I2S controller */
i2s->CON |= (I2S_CON_RXEN_Msk | I2S_CON_TXEN_Msk | I2S_CON_I2SEN_Msk);
return u32SampleRate;
}
/**
* @brief Disable I2S function.
* @param[in] i2s The pointer of the specified I2S module.
* @return None
* @details Disable I2S function.
*/
void I2S_Close(I2S_T *i2s)
{
i2s->CON &= ~I2S_CON_I2SEN_Msk;
}
/**
* @brief Enable interrupt function.
* @param[in] i2s The pointer of the specified I2S module.
* @param[in] u32Mask The combination of all related interrupt enable bits.
* Each bit corresponds to a interrupt bit. Valid values are:
* - \ref I2S_IE_LZCIE_Msk
* - \ref I2S_IE_RZCIE_Msk
* - \ref I2S_IE_TXTHIE_Msk
* - \ref I2S_IE_TXOVFIE_Msk
* - \ref I2S_IE_TXUDFIE_Msk
* - \ref I2S_IE_RXTHIE_Msk
* - \ref I2S_IE_RXOVFIE_Msk
* - \ref I2S_IE_RXUDFIE_Msk
* @return None
* @details This function enables the interrupt according to the mask parameter.
*/
void I2S_EnableInt(I2S_T *i2s, uint32_t u32Mask)
{
i2s->IE |= u32Mask;
}
/**
* @brief Disable interrupt function.
* @param[in] i2s The pointer of the specified I2S module.
* @param[in] u32Mask The combination of all related interrupt enable bits.
* Each bit corresponds to a interrupt bit. Valid values are:
* - \ref I2S_IE_LZCIE_Msk
* - \ref I2S_IE_RZCIE_Msk
* - \ref I2S_IE_TXTHIE_Msk
* - \ref I2S_IE_TXOVFIE_Msk
* - \ref I2S_IE_TXUDFIE_Msk
* - \ref I2S_IE_RXTHIE_Msk
* - \ref I2S_IE_RXOVFIE_Msk
* - \ref I2S_IE_RXUDFIE_Msk
* @return None
* @details This function disables the interrupt according to the mask parameter.
*/
void I2S_DisableInt(I2S_T *i2s, uint32_t u32Mask)
{
i2s->IE &= ~u32Mask;
}
/**
* @brief Enable master clock (MCLK).
* @param[in] i2s The pointer of the specified I2S module.
* @param[in] u32BusClock The target MCLK clock.
* @return Actual MCLK clock
* @details Set the master clock rate according to u32BusClock parameter and enable master clock output.
* The actual master clock rate may be different from the target master clock rate. The real master clock rate will be returned for reference.
*/
uint32_t I2S_EnableMCLK(I2S_T *i2s, uint32_t u32BusClock)
{
uint32_t u32Divider;
uint32_t u32SrcClk, u32Reg;
u32SrcClk = I2S_GetSourceClockFreq(i2s);
if(u32BusClock == u32SrcClk)
u32Divider = 0;
else
u32Divider = (u32SrcClk / u32BusClock) >> 1;
i2s->CLKDIV = (i2s->CLKDIV & ~I2S_CLKDIV_MCLK_DIV_Msk) | u32Divider;
i2s->CON |= I2S_CON_MCLKEN_Msk;
u32Reg = i2s->CLKDIV & I2S_CLKDIV_MCLK_DIV_Msk;
if(u32Reg == 0)
return u32SrcClk;
else
return ((u32SrcClk >> 1) / u32Reg);
}
/**
* @brief Disable master clock (MCLK).
* @param[in] i2s The pointer of the specified I2S module.
* @return None
* @details Disable master clock output.
*/
void I2S_DisableMCLK(I2S_T *i2s)
{
i2s->CON &= ~I2S_CON_MCLKEN_Msk;
}
/*@}*/ /* end of group I2S_EXPORTED_FUNCTIONS */
/*@}*/ /* end of group I2S_Driver */
/*@}*/ /* end of group Standard_Driver */
/*** (C) COPYRIGHT 2014~2015 Nuvoton Technology Corp. ***/