i2c.c

此压缩包为杰得开发得z228的BSP的源代码,可以实现很多功能,尤其是视频解码有很好的效果.

/********************************************/
/* I2C.c: implementation of the I2C API.		*/
/* Author   : qzsu													*/
/* Time     : 2006-08-21										*/
/********************************************/

#include <string.h>
#include ".\inc\I2C.h"

#ifdef I2C_WINCE

#include <windows.h>
#include <ceddk.h>
#include <Pkfuncs.h>
#include "hw_lib.h"



#endif


#define	PHY_I2C_BASE	0x20036000
#define PIN_MASKBASE	0x20020000

U8 *g_i2c_base;

U32 *pinmark = NULL;

void I2C_delay(U32 us);


// Receive FIFO Completely Full
bool IsRFF(void);

// Receive FIFO Not Empty
bool IsRFNE(void);

// Transmit FIFO Completely Empty
bool IsTFE(void);


/* The following API are used to access the State Register*/

// Receive FIFO Completely Full
bool IsRFF(void)
{
	if(I2C_STATUS & RFF)
	{
		return true;
	}
	else
	{
		return false;
	}
}

// Receive FIFO Not Empty
bool IsRFNE(void)
{
	if(I2C_STATUS & RFNE)
	{
		return true;
	}
	else
	{
		return false;
	}
}

// Transmit FIFO Completely Empty
bool IsTFE(void)
{
	if(I2C_STATUS & TFE)
	{
		return true;
	}
	else
	{
		return false;
	}
}

//end the state Register API


void I2C_PinMask(  U32 enable )
{
//	volatile int* pinmark = NULL;
#ifdef I2C_WINCE	
//	pinmark = (volatile int*)hw_map_io( PIN_MASKBASE , 0x1000 , 0 );
//	RETAILMSG(1,(_T("pinmark:%x\r\n"),pinmark));
	hw_delay(1);
#else
	pinmark = (U32*) PIN_MASKBASE;
#endif
	
	if( pinmark )
	{
		if( enable )
			pinmark[0x10c/4] |= 0x400;
		else
			pinmark[0x10c/4] &= ~0x400;

	}
}

/* brief : Initialize the I2C module */
void InitI2C(void)
{
#ifdef I2C_WINCE
	g_i2c_base = (U8 *)(hw_map_io(PHY_I2C_BASE, 0x1000, 0));
	pinmark = (U32*)hw_map_io( PIN_MASKBASE , 0x1000 , 0 );
//	RETAILMSG(1,(_T("g_i2c_base:%x\r\n"),g_i2c_base));
	hw_delay(1);

#else
	g_i2c_base = (U8*)PHY_I2C_BASE;
#endif	
	
	// Define the Initialize parameters 

	//Disable the I2C MASTER
	I2C_DISABLE;
	
	//Set the address if targeted as a slave
//	I2C_SAR(0x0045);
	
	//Set the control register for the transfer
	I2C_CON(0x0003);
	
	//-: Set the High period for the SCL 
	//(we have 10 MHz ic_clk) if we want 100kbps , SS_HCNT = 0x0028
  //Set the Low period for the SCL
  //(we have 10 MHz ic_clk) if we want 100kbps , SS_LCNG =0x002f
	I2C_SS_HCNT(0x0028);
	I2C_SS_LCNT(0x002f);
  
  //Set the address for the target register(slave)
//  I2C_TAR(0x0056);

  //Enable interrupts
  I2C_INTR_MASK(0);

  //Set Rx FIFO Threshold 
  I2C_RX_TL(0);

  //Set Tx FIFO Threshold 
  I2C_TX_TL(0);
	
	//Enable the I2C MASTER
	I2C_ENABLE;
	

}

void DeleteI2C(void)
{
#ifdef I2C_WINCE
	if(g_i2c_base)
	{
		hw_unmap_io(g_i2c_base , 0x1000);
	}
	if(pinmark)
	{
		hw_unmap_io( (void*)pinmark , 0x1000);
	}
#endif	
}


/* brief: This API is used to transmit data 
** para : threhold -- the  threhole of the FIFO
** para : buffer -- the pointer of data
** para : target -- the address of the target
** ret  : retvalue is 1 means , threhold value is not illegal;
*/ 
int TransmitData(const int threhold, const unsigned char buffer[], const unsigned short target)
{
	int i;

	if(!g_i2c_base)
	{
		return -1;
	}

	
	if(threhold < 0 || threhold >255)
	{
		return -1;
	}
	
	I2C_DISABLE;
	
	I2C_TX_TL((threhold-1));

	I2C_TAR(target);			

	I2C_ENABLE;

	while(!IsTFE());	
	
	i=0;
	while(i < threhold)
	{
		I2C_WRITE (buffer[i++]);
		while(!IsTFE());	
	}
			
	return 0;
}


int ReadData(const int threhold, const unsigned char buffer[], const unsigned short target)
{
	volatile int retValue = 0 ,i;

	if(!g_i2c_base)
	{
		return -1;
	}
	
	//dw	
	if(threhold < 0 || threhold >255){
		retValue = -1;
		return retValue;
	}

	I2C_DISABLE;
	
	I2C_TX_TL((threhold-1));

	I2C_TAR(target);			

	I2C_ENABLE;

	while(!IsTFE());	


	//wa
	i=0;
	while(i < threhold)
	{
		I2C_WRITE (buffer[i++]);
		while(!IsTFE());	
	}		

	//sr
	I2C_CON(I2CR_CON | 0x20);//IC_RESTART_EN
		
	//dr
	while(!IsTFE());	

	I2C_WRITE(0x141);			//read operation

	while(!IsTFE());	
	
	//data
	while(!IsRFNE());

	while(IsRFF());	

	retValue = I2C_READ;
	
	return retValue;
}


void I2C_delay(U32 us)
{
	U32 count;
	
	count = 22;//266/12(1us)
	while(us--)
	{
		while(count--);
	}
}