lpc_i2s.c

/**********************************************************************
* $Id$      lpc_i2s.c           2011-06-02
*//**
* @file     lpc_i2s.c
* @brief    Contains all functions support for I2S firmware library
*           on LPC
* @version  1.0
* @date     02. June. 2011
* @author   NXP MCU SW Application Team
* 
* Copyright(C) 2011, NXP Semiconductor
* All rights reserved.
*
***********************************************************************
* Software that is described herein is for illustrative purposes only
* which provides customers with programming information regarding the
* products. This software is supplied "AS IS" without any warranties.
* NXP Semiconductors assumes no responsibility or liability for the
* use of the software, conveys no license or title under any patent,
* copyright, or mask work right to the product. NXP Semiconductors
* reserves the right to make changes in the software without
* notification. NXP Semiconductors also make no representation or
* warranty that such application will be suitable for the specified
* use without further testing or modification.
* Permission to use, copy, modify, and distribute this software and its
* documentation is hereby granted, under NXP Semiconductors'
* relevant copyright in the software, without fee, provided that it
* is used in conjunction with NXP Semiconductors microcontrollers.  This
* copyright, permission, and disclaimer notice must appear in all copies of
* this code.
**********************************************************************/

/* Peripheral group ----------------------------------------------------------- */
/** @addtogroup I2S
 * @{
 */
#ifdef __BUILD_WITH_EXAMPLE__
#include "lpc_libcfg.h"
#else
#include "lpc_libcfg_default.h"
#endif /* __BUILD_WITH_EXAMPLE__ */
#ifdef _I2S

/* Includes ------------------------------------------------------------------- */
#include "lpc_i2s.h"
#include "lpc_clkpwr.h"

/* definitions ---------------------------------------------------------- */
#define    I2S_IS_ENABLED(x)   ((x)? ENABLE:DISABLE)
/* Private Functions ---------------------------------------------------------- */

static uint8_t i2s_GetWordWidth(LPC_I2S_TypeDef *I2Sx, uint8_t TRMode);
static uint8_t i2s_GetChannel(LPC_I2S_TypeDef *I2Sx, uint8_t TRMode);

/********************************************************************//**
 * @brief       Get I2S wordwidth value
 * @param[in]   I2Sx I2S peripheral selected, should be: LPC_I2S
 * @param[in]   TRMode is the I2S mode, should be:
 *              - I2S_TX_MODE = 0: transmit mode
 *              - I2S_RX_MODE = 1: receive mode
 * @return      The wordwidth value, should be: 8,16 or 32
 *********************************************************************/
static uint8_t i2s_GetWordWidth(LPC_I2S_TypeDef *I2Sx, uint8_t TRMode) {
    uint8_t value;

    if (TRMode == I2S_TX_MODE) {
        value = (I2Sx->DAO) & 0x03; /* get wordwidth bit */
    } else {
        value = (I2Sx->DAI) & 0x03; /* get wordwidth bit */
    }
    switch (value) {
    case I2S_WORDWIDTH_8:
        return 8;
    case I2S_WORDWIDTH_16:
        return 16;
    default:
        return 32;
    }
}

/********************************************************************//**
 * @brief       Get I2S channel value
 * @param[in]   I2Sx I2S peripheral selected, should be: LPC_I2S
 * @param[in]   TRMode is the I2S mode, should be:
 *              - I2S_TX_MODE = 0: transmit mode
 *              - I2S_RX_MODE = 1: receive mode
 * @return      The channel value, should be: 1(mono) or 2(stereo)
 *********************************************************************/
static uint8_t i2s_GetChannel(LPC_I2S_TypeDef *I2Sx, uint8_t TRMode) {
    uint8_t value;

    if (TRMode == I2S_TX_MODE) {
        value = ((I2Sx->DAO) & 0x04)>>2; /* get bit[2] */
    } else {
        value = ((I2Sx->DAI) & 0x04)>>2; /* get bit[2] */
    }
        if(value == I2S_MONO) return 1;
          return 2;
}

/* End of Private Functions --------------------------------------------------- */


/* Public Functions ----------------------------------------------------------- */
/** @addtogroup I2S_Public_Functions
 * @{
 */

/********************************************************************//**
 * @brief       Initialize I2S
 *                  - Turn on power and clock
 * @param[in]   I2Sx I2S peripheral selected, should be: LPC_I2S
 * @return      none
 *********************************************************************/
void I2S_Init(LPC_I2S_TypeDef *I2Sx) {
    // Turn on power and clock
    CLKPWR_ConfigPPWR(CLKPWR_PCONP_PCI2S, ENABLE);
    LPC_I2S->DAI = LPC_I2S->DAO = 0x00;
}

/********************************************************************//**
 * @brief       Configuration I2S, setting:
 *                  - master/slave mode
 *                  - wordwidth value
 *                  - channel mode
 * @param[in]   I2Sx I2S peripheral selected, should be: LPC_I2S
 * @param[in]   TRMode transmit/receive mode, should be:
 *                  - I2S_TX_MODE = 0: transmit mode
 *                  - I2S_RX_MODE = 1: receive mode
 * @param[in]   ConfigStruct pointer to I2S_CFG_Type structure
 *              which will be initialized.
 * @return      none
 *********************************************************************/
void I2S_Config(LPC_I2S_TypeDef *I2Sx, uint8_t TRMode, I2S_CFG_Type* ConfigStruct)
{
    uint32_t bps, config;
    /* Setup clock */
    bps = (ConfigStruct->wordwidth +1)*8;

    /* Calculate audio config */
    config = (bps - 1)<<6 | (ConfigStruct->ws_sel)<<5 | (ConfigStruct->reset)<<4 |
        (ConfigStruct->stop)<<3 | (ConfigStruct->mono)<<2 | (ConfigStruct->wordwidth);

    if(TRMode == I2S_RX_MODE){
        LPC_I2S->DAI = config;
    }else{
        LPC_I2S->DAO = config;
    }
}

/********************************************************************//**
 * @brief       DeInitial both I2S transmit or receive
 * @param[in]   I2Sx I2S peripheral selected, should be: LPC_I2S
 * @return      none
 *********************************************************************/
void I2S_DeInit(LPC_I2S_TypeDef *I2Sx) {
    // Turn off power and clock
    CLKPWR_ConfigPPWR(CLKPWR_PCONP_PCI2S, DISABLE);
}

/********************************************************************//**
 * @brief       Get I2S Buffer Level
 * @param[in]   I2Sx I2S peripheral selected, should be: LPC_I2S
 * @param[in]   TRMode Transmit/receive mode, should be:
 *                  - I2S_TX_MODE = 0: transmit mode
 *                  - I2S_RX_MODE = 1: receive mode
 * @return      current level of Transmit/Receive Buffer
 *********************************************************************/
uint8_t I2S_GetLevel(LPC_I2S_TypeDef *I2Sx, uint8_t TRMode)
{

    if(TRMode == I2S_TX_MODE)
    {
        return ((I2Sx->STATE >> 16) & 0xFF);
    }
    else
    {
        return ((I2Sx->STATE >> 8) & 0xFF);
    }
}

/********************************************************************//**
 * @brief       I2S Start: clear all STOP,RESET and MUTE bit, ready to operate
 * @param[in]   I2Sx I2S peripheral selected, should be: LPC_I2S
 * @return      none
 *********************************************************************/
void I2S_Start(LPC_I2S_TypeDef *I2Sx)
{
    //Clear STOP,RESET and MUTE bit
    I2Sx->DAO &= ~I2S_DAI_RESET;
    I2Sx->DAI &= ~I2S_DAI_RESET;
    I2Sx->DAO &= ~I2S_DAI_STOP;
    I2Sx->DAI &= ~I2S_DAI_STOP;
    I2Sx->DAO &= ~I2S_DAI_MUTE;
}

/********************************************************************//**
 * @brief       I2S Send data
 * @param[in]   I2Sx I2S peripheral selected, should be: LPC_I2S
 * @param[in]   BufferData pointer to uint32_t is the data will be send
 * @return      none
 *********************************************************************/
void I2S_Send(LPC_I2S_TypeDef *I2Sx, uint32_t BufferData)
{
    I2Sx->TXFIFO = BufferData;
}

/********************************************************************//**
 * @brief       I2S Receive Data
 * @param[in]   I2Sx pointer to LPC_I2S_TypeDef
 * @return      received value
 *********************************************************************/
uint32_t I2S_Receive(LPC_I2S_TypeDef* I2Sx)
{
    return (I2Sx->RXFIFO);
}

/********************************************************************//**
 * @brief       I2S Pause
 * @param[in]   I2Sx I2S peripheral selected, should be: LPC_I2S
 * @param[in]   TRMode is transmit/receive mode, should be:
 *              - I2S_TX_MODE = 0: transmit mode
 *              - I2S_RX_MODE = 1: receive mode
 * @return      none
 *********************************************************************/
void I2S_Pause(LPC_I2S_TypeDef *I2Sx, uint8_t TRMode) {
    if (TRMode == I2S_TX_MODE) //Transmit mode
    {
        I2Sx->DAO |= I2S_DAO_STOP;
    } else //Receive mode
    {
        I2Sx->DAI |= I2S_DAI_STOP;
    }
}

/********************************************************************//**
 * @brief       I2S Mute
 * @param[in]   I2Sx I2S peripheral selected, should be: LPC_I2S
 * @param[in]   TRMode is transmit/receive mode, should be:
 *              - I2S_TX_MODE = 0: transmit mode
 *              - I2S_RX_MODE = 1: receive mode
 * @return      none
 *********************************************************************/
void I2S_Mute(LPC_I2S_TypeDef *I2Sx, uint8_t TRMode) {
    if (TRMode == I2S_TX_MODE) //Transmit mode
    {
        I2Sx->DAO |= I2S_DAO_MUTE;
    } else //Receive mode
    {
        I2Sx->DAI |= I2S_DAI_MUTE;
    }
}

/********************************************************************//**
 * @brief       I2S Stop
 * @param[in]   I2Sx I2S peripheral selected, should be: LPC_I2S
 * @param[in]   TRMode is transmit/receive mode, should be:
 *              - I2S_TX_MODE = 0: transmit mode
 *              - I2S_RX_MODE = 1: receive mode
 * @return      none
 *********************************************************************/
void I2S_Stop(LPC_I2S_TypeDef *I2Sx, uint8_t TRMode) {
    if (TRMode == I2S_TX_MODE) //Transmit mode
    {
        I2Sx->DAO &= ~I2S_DAO_MUTE;
        I2Sx->DAO |= I2S_DAO_STOP;
        I2Sx->DAO |= I2S_DAO_RESET;
    } else //Receive mode
    {
        I2Sx->DAI |= I2S_DAI_STOP;
        I2Sx->DAI |= I2S_DAI_RESET;
    }
}
/********************************************************************//**
 * @brief       Set frequency for I2S
 * @param[in]   I2Sx I2S peripheral selected, should be: LPC_I2S
 * @param[in]   Freq is the frequency for I2S will be set. It can range
 *              from 16-96 kHz(16, 22.05, 32, 44.1, 48, 96kHz)
 * @param[in]   TRMode is transmit/receive mode, should be:
 *              - I2S_TX_MODE = 0: transmit mode
 *              - I2S_RX_MODE = 1: receive mode
 * @return      Status: ERROR or SUCCESS
 *********************************************************************/
Status I2S_FreqConfig(LPC_I2S_TypeDef *I2Sx, uint32_t Freq, uint8_t TRMode) {
    uint32_t cclk;
    uint8_t channel, wordwidth;
    uint32_t x, y;
    uint64_t divider;
    uint16_t dif;
    uint16_t x_divide, y_divide;
    uint16_t err, ErrorOptimal = 0xFFFF;
    
    uint32_t N;

    //get cclk 
    cclk = CLKPWR_GetCLK(CLKPWR_CLKTYPE_CPU);

    if(TRMode == I2S_TX_MODE)
    {
        channel = i2s_GetChannel(I2Sx,I2S_TX_MODE);
        wordwidth = i2s_GetWordWidth(I2Sx,I2S_TX_MODE);
    }
    else
    {
        channel = i2s_GetChannel(I2Sx,I2S_RX_MODE);
        wordwidth = i2s_GetWordWidth(I2Sx,I2S_RX_MODE);
    }

    /* Calculate X and Y divider
     * The MCLK rate for the I2S transmitter is determined by the value
     * in the I2STXRATE/I2SRXRATE register. The required I2STXRATE/I2SRXRATE
     * setting depends on the desired audio sample rate desired, the format
     * (stereo/mono) used, and the data size.
     * The formula is:
     *      I2S_MCLK = CCLK * (X/Y) / 2
     * We have:
     *      I2S_MCLK = Freq * channel*wordwidth * (I2Sx->TXBITRATE+1);
     * So: (X/Y) = (Freq * channel*wordwidth * (I2Sx->TXBITRATE+1))/CCLK*2
     * We use a loop function to chose the most suitable X,Y value
     */

    /* divider is a fixed point number with 16 fractional bits */
    divider = (((uint64_t)Freq *channel*wordwidth * 2)<<16) / cclk;

    /* find N that make x/y <= 1 -> divider <= 2^16 */
    for(N=64;N>0;N--){
        if((divider*N) < (1<<16)) break;
    }

    if(N == 0) return ERROR;

    divider *= N;

    for (y = 255; y > 0; y--) {
        x = y * divider;
        if(x & (0xFF000000)) continue;
        dif = x & 0xFFFF;
        if(dif>0x8000) err = 0x10000-dif;
        else err = dif;
        if (err == 0)
        {
            y_divide = y;
            break;
        }
        else if (err < ErrorOptimal)
        {
            ErrorOptimal = err;
            y_divide = y;
        }
    }
    x_divide = ((uint64_t)y_divide * Freq *(channel*wordwidth)* N * 2)/cclk;
    if(x_divide >= 256) x_divide = 0xFF;
    if(x_divide == 0) x_divide = 1;
    
    if (TRMode == I2S_TX_MODE)// Transmitter
    {
        I2Sx->TXBITRATE = N-1;
        I2Sx->TXRATE = y_divide | (x_divide << 8);
    } else //Receiver
    {
        I2Sx->RXBITRATE = N-1;
        I2Sx->TXRATE = y_divide | (x_divide << 8);
    }
    return SUCCESS;
}

/********************************************************************//**
 * @brief       I2S set bitrate
 * @param[in]   I2Sx I2S peripheral selected, should be: LPC_I2S
 * @param[in]   bitrate value will be set
 *              bitrate value should be in range: 0 .. 63
 * @param[in]   TRMode is transmit/receive mode, should be:
 *              - I2S_TX_MODE = 0: transmit mode
 *              - I2S_RX_MODE = 1: receive mode
 * @return      none
 *********************************************************************/
void I2S_SetBitRate(LPC_I2S_TypeDef *I2Sx, uint8_t bitrate, uint8_t TRMode)
{
    if(TRMode == I2S_TX_MODE)
    {
        I2Sx->TXBITRATE = bitrate;
    }
    else
    {
        I2Sx->RXBITRATE = bitrate;
    }
}

/********************************************************************//**
 * @brief       Configuration operating mode for I2S
 * @param[in]   I2Sx I2S peripheral selected, should be: LPC_I2S
 * @param[in]   ModeConfig pointer to I2S_MODEConf_Type will be used to
 *              configure
 * @param[in]   TRMode is transmit/receive mode, should be:
 *              - I2S_TX_MODE = 0: transmit mode
 *              - I2S_RX_MODE = 1: receive mode
 * @return      none
 *********************************************************************/
void I2S_ModeConfig(LPC_I2S_TypeDef *I2Sx, I2S_MODEConf_Type* ModeConfig,
        uint8_t TRMode)
{
    if (TRMode == I2S_TX_MODE) {
        I2Sx->TXMODE &= ~0x0F; //clear bit 3:0 in I2STXMODE register
        if (ModeConfig->clksel == I2S_CLKSEL_MCLK) {
            I2Sx->TXMODE |= 0x02;
        }
        if (ModeConfig->fpin == I2S_4PIN_ENABLE) {
            I2Sx->TXMODE |= (1 << 2);
        }
        if (ModeConfig->mcena == I2S_MCLK_ENABLE) {
            I2Sx->TXMODE |= (1 << 3);
        }
    } else {
        I2Sx->RXMODE &= ~0x0F; //clear bit 3:0 in I2STXMODE register
        if (ModeConfig->clksel == I2S_CLKSEL_MCLK) {
            I2Sx->RXMODE |= 0x02;
        }
        if (ModeConfig->fpin == I2S_4PIN_ENABLE) {
            I2Sx->RXMODE |= (1 << 2);
        }
        if (ModeConfig->mcena == I2S_MCLK_ENABLE) {
            I2Sx->RXMODE |= (1 << 3);
        }
    }
}

/********************************************************************//**
 * @brief       Configure DMA operation for I2S
 * @param[in]   I2Sx I2S peripheral selected, should be: LPC_I2S
 * @param[in]   DMAConfig pointer to I2S_DMAConf_Type will be used to configure
 * @param[in]   TRMode is transmit/receive mode, should be:
 *              - I2S_TX_MODE = 0: transmit mode
 *              - I2S_RX_MODE = 1: receive mode
 * @return      none
 *********************************************************************/
void I2S_DMAConfig(LPC_I2S_TypeDef *I2Sx, I2S_DMAConf_Type* DMAConfig,
        uint8_t TRMode)
{
    if (TRMode == I2S_RX_MODE) {
        if (DMAConfig->DMAIndex == I2S_DMA_1) {
            LPC_I2S->DMA1 = (DMAConfig->depth) << 8;
        } else {
            LPC_I2S->DMA2 = (DMAConfig->depth) << 8;
        }
    } else {
        if (DMAConfig->DMAIndex == I2S_DMA_1) {
            LPC_I2S->DMA1 = (DMAConfig->depth) << 16;
        } else {
            LPC_I2S->DMA2 = (DMAConfig->depth) << 16;
        }
    }
}

/********************************************************************//**
 * @brief       Enable/Disable DMA operation for I2S
 * @param[in]   I2Sx: I2S peripheral selected, should be: LPC_I2S
 * @param[in]   DMAIndex chose what DMA is used, should be:
 *              - I2S_DMA_1 = 0: DMA1
 *              - I2S_DMA_2 = 1: DMA2
 * @param[in]   TRMode is transmit/receive mode, should be:
 *              - I2S_TX_MODE = 0: transmit mode
 *              - I2S_RX_MODE = 1: receive mode
 * @param[in]   NewState is new state of DMA operation, should be:
 *              - ENABLE
 *              - DISABLE
 * @return      none
 *********************************************************************/
void I2S_DMACmd(LPC_I2S_TypeDef *I2Sx, uint8_t DMAIndex, uint8_t TRMode,
        FunctionalState NewState)
{
    if (TRMode == I2S_RX_MODE) {
        if (DMAIndex == I2S_DMA_1) {
            if (NewState == ENABLE)
                I2Sx->DMA1 |= 0x01;
            else
                I2Sx->DMA1 &= ~0x01;
        } else {
            if (NewState == ENABLE)
                I2Sx->DMA2 |= 0x01;
            else
                I2Sx->DMA2 &= ~0x01;
        }
    } else {
        if (DMAIndex == I2S_DMA_1) {
            if (NewState == ENABLE)
                I2Sx->DMA1 |= 0x02;
            else
                I2Sx->DMA1 &= ~0x02;
        } else {
            if (NewState == ENABLE)
                I2Sx->DMA2 |= 0x02;
            else
                I2Sx->DMA2 &= ~0x02;
        }
    }
}

/********************************************************************//**
 * @brief       Configure IRQ for I2S
 * @param[in]   I2Sx I2S peripheral selected, should be: LPC_I2S
 * @param[in]   TRMode is transmit/receive mode, should be:
 *              - I2S_TX_MODE = 0: transmit mode
 *              - I2S_RX_MODE = 1: receive mode
 * @param[in]   level is the FIFO level that triggers IRQ request
 * @return      none
 *********************************************************************/
void I2S_IRQConfig(LPC_I2S_TypeDef *I2Sx, uint8_t TRMode, uint8_t level) {
    if (TRMode == I2S_RX_MODE) {
        I2Sx->IRQ |= (level << 8);
    } else {
        I2Sx->IRQ |= (level << 16);
    }
}

/********************************************************************//**
 * @brief       Enable/Disable IRQ for I2S
 * @param[in]   I2Sx I2S peripheral selected, should be: LPC_I2S
 * @param[in]   TRMode is transmit/receive mode, should be:
 *              - I2S_TX_MODE = 0: transmit mode
 *              - I2S_RX_MODE = 1: receive mode
 * @param[in]   NewState is new state of DMA operation, should be:
 *              - ENABLE
 *              - DISABLE
 * @return      none
 *********************************************************************/
void I2S_IRQCmd(LPC_I2S_TypeDef *I2Sx, uint8_t TRMode, FunctionalState NewState) {

    if (TRMode == I2S_RX_MODE) {
        if (NewState == ENABLE)
            I2Sx->IRQ |= 0x01;
        else
            I2Sx->IRQ &= ~0x01;
        //Enable DMA

    } else {
        if (NewState == ENABLE)
            I2Sx->IRQ |= 0x02;
        else
            I2Sx->IRQ &= ~0x02;
    }
}

/********************************************************************//**
 * @brief       Get I2S interrupt status
 * @param[in]   I2Sx I2S peripheral selected, should be: LPC_I2S
 * @param[in]   TRMode is transmit/receive mode, should be:
 *              - I2S_TX_MODE = 0: transmit mode
 *              - I2S_RX_MODE = 1: receive mode
 * @return      FunctionState   should be:
 *              - ENABLE: interrupt is enable
 *              - DISABLE: interrupt is disable
 *********************************************************************/
FunctionalState I2S_GetIRQStatus(LPC_I2S_TypeDef *I2Sx,uint8_t TRMode)
{

    if(TRMode == I2S_TX_MODE)
        return I2S_IS_ENABLED((I2Sx->IRQ >> 1)&0x01);
    else
        return I2S_IS_ENABLED((I2Sx->IRQ)&0x01);
}

/********************************************************************//**
 * @brief       Get I2S interrupt depth
 * @param[in]   I2Sx I2S peripheral selected, should be: LPC_I2S
 * @param[in]   TRMode is transmit/receive mode, should be:
 *              - I2S_TX_MODE = 0: transmit mode
 *              - I2S_RX_MODE = 1: receive mode
 * @return      depth of FIFO level on which to create an irq request
 *********************************************************************/
uint8_t I2S_GetIRQDepth(LPC_I2S_TypeDef *I2Sx,uint8_t TRMode)
{

    if(TRMode == I2S_TX_MODE)
        return (((I2Sx->IRQ)>>16)&0xFF);
    else
        return (((I2Sx->IRQ)>>8)&0xFF);
}
/**
 * @}
 */

#endif /*_I2S*/

/**
 * @}
 */

/* --------------------------------- End Of File ------------------------------ */