S3C2416裸機開發(fā)系列十八_音頻驅動實現(2)

標簽：WM8960IIS音頻驅動s3c2416裸機開發(fā)

2014-06-10 09:50853人閱讀評論(0)收藏舉報

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s3c2416裸機開發(fā)（24）

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象棋小子 1048272975

IIS模塊實現IIS.c如下：

#include"s3c2416.h"

#include "IIS.h"

#include"Exception.h"

#include"UART0.h"

#defineDEBUG_IIS

#ifdef DEBUG_IIS

#defineDebug(x...) Uart0_Printf(x)

#else

#defineDebug(x...)

#endif

staticunsigned char TX_Channel; // 發(fā)送音頻的聲道數

staticunsigned char TX_BitLen; // 發(fā)送位長

staticunsigned char RX_Channel; // 接收音頻的聲道數

staticunsigned char RX_BitLen; // 接收位長

staticvolatile unsigned char TxBufferFlag;

staticvolatile unsigned char RxBufferFlag;

staticunsigned int TxCount; // 播放時記錄緩存中的寫位置

staticunsigned int RxCount; // 錄音時記錄緩存中的讀位置

// 插放與錄音均采用雙緩存,DMA傳輸的主存與cache會有數據一致性問題

// 音頻DMA緩存分配到不開啟cache的內存區(qū)域

staticunsigned int TxBuffer0[4*1024] __attribute__((section("No_Cache"),zero_init));

staticunsigned int TxBuffer1[4*1024] __attribute__((section("No_Cache"),zero_init));

staticunsigned int RxBuffer0[4*1024] __attribute__((section("No_Cache"),zero_init));

staticunsigned int RxBuffer1[4*1024] __attribute__((section("No_Cache"),zero_init));

static voidDMA_IRQ(void)

{

static unsigned char TxBufferChannel = 0;

static unsigned char RxBufferChannel = 0;

unsigned int DMA_Channel;

DMA_Channel = rSUBSRCPND;

if (DMA_Channel &(1<

if (TxBufferChannel == 0) {

rDISRC0 = ((unsigned int)TxBuffer1);// 開始使用Buffer1緩存

TxBufferFlag &= ~(1<<0);// 發(fā)送標志0位清空,說明Buffer0數據需填充

TxBufferChannel = 1; // 正在發(fā)送Buffer1緩存

} else {

rDISRC0 = ((unsignedint)TxBuffer0);// 開始使用Buffer0緩存

TxBufferFlag &= ~(1<<1);// 發(fā)送標志1位清空,說明Buffer1數據需填充

TxBufferChannel = 0; // 正在發(fā)送Buffer0緩存

}

rDCON0 = (rDCON0&(~0xfffff)) |(sizeof(TxBuffer0)/4);

rDMASKTRIG0 = (1<<1); // IIS TX打開DMA0通道

rSUBSRCPND |= (1<

}

if (DMA_Channel &(1<

if (RxBufferChannel == 0) {

rDIDST1 = ((unsigned int)RxBuffer1);// DMA1目的地址

RxBufferFlag |= (1<<0); // 接收緩存0位置位,說明Buffer0數據準備好

RxBufferChannel = 1; // 下一次使用Buffer1

} else {

rDIDST1 = ((unsigned int)RxBuffer0);// DMA1目的地址

RxBufferFlag |= (1<<1); // 接收緩存1位置位,說明Buffer1數據準備好

RxBufferChannel = 0; // 下一次使用Buffer0

}

rDCON1 = (rDCON1&(~0xfffff)) |(sizeof(RxBuffer0)/4);

rDMASKTRIG1 = (1<<1); // IIS RX打開DMA1通道

rSUBSRCPND |= (1<

}

rSRCPND1 |= (1 << INT_DMA);

rINTPND1 |= (1 << INT_DMA);

}

unsignedint IIS_WriteBuffer(unsigned char *pData, unsigned int MaxLen)

{

unsigned int i;

unsigned int nCount; // 能寫入buffer中數據長度(以字計,fifo 32位長)

unsigned int *pBuffer;

unsigned char *pTemp = pData;

if (pTemp==0 || MaxLen==0) {

return 0; // 參數錯誤,數據未寫入緩存

}

if ((TxBufferFlag&0x3) == 0x3) {

return 0; // Buffer0,Buffer1均已寫滿

}

if (!(TxBufferFlag & (1<<0))) { //Buffer0需填充

pBuffer = &TxBuffer0[TxCount];

} else { // Buffer1需填充

pBuffer = &TxBuffer1[TxCount];

}

nCount = (sizeof(TxBuffer0)/4) - TxCount;

switch (TX_BitLen) {

case 8:

if (TX_Channel != 1) { // 雙聲道

if (MaxLen/2 == 0) {// 左右聲道fifo中有兩個8位有效音頻數據

pTemp += MaxLen; // 不足一個采樣2字節(jié)數據,丟棄寫入buffer中

}

MaxLen = MaxLen/2; // 32位的fifo中有兩個8位有效音頻數據

if (MaxLen < nCount) {

nCount = MaxLen;

}

for (i=0; i

*pBuffer++ = (((unsignedint)pTemp[1]<<16)+

((unsignedint)pTemp[0]<<0));

pTemp += 2; // 2個8位的聲道數據已寫入buffer中

}

} else { // 單聲道

if (MaxLen < nCount) {// 32位的fifo中有一個8位有效音頻數據

nCount = MaxLen;

}

for (i=0; i

*pBuffer++ = (unsignedint)pTemp[0]<<0;

pTemp += 1; // 1個8位的聲道數據已寫入FIFO中

}

}

break;

case 16:

if (TX_Channel != 1) { // 雙聲道

if (MaxLen/4 == 0) {// 左右聲道fifo中有四個8位有效音頻數據

pTemp += MaxLen; // 不足一個采樣4字節(jié)數據,丟棄寫入buffer中

}

MaxLen = MaxLen/4; // 32位的fifo中有四個8位有效音頻數據

if (MaxLen < nCount) {

nCount = MaxLen;

}

for (i=0; i

*pBuffer++ = (((unsignedint)pTemp[0]<<0) +

((unsignedint)pTemp[1]<<8)) +