s3c44b0iic.c

S3C44B0 I2C的uCLINUX的驱动程序（铁电存储器FM24系列

#include <linux/config.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>

#include <linux/miscdevice.h>
#include <linux/sched.h>
#include <linux/delay.h>
#include <linux/poll.h>
#include <linux/spinlock.h>
#include <linux/delay.h>
#include <asm/irq.h>
#include <asm/hardware.h>

#define U32 unsigned int
#define U16 unsigned short
#define S32 int
#define S16 short int
#define U8 unsigned char


/* I/O PORT */

#define PCONF		(*(volatile unsigned *)0x1d20034)
#define PDATF		(*(volatile unsigned *)0x1d20038)
#define PUPF		(*(volatile unsigned *)0x1d2003c)

#define IICCON         (*(volatile unsigned *)0x1d60000)
#define IICSTAT        (*(volatile unsigned *)0x1d60004)
#define IICADD         (*(volatile unsigned *)0x1d60008)
#define IICDS          (*(volatile unsigned *)0x1d6000c)


#ifdef CONFIG_DEVFS_FS
static devfs_handle_t devfs_iic_dir, devfs_iicraw;
#endif

#define SKQ_IIC_MODULE_NAME     "IICBUS"
/*60--63,120--127,240--254*/
#define IICBUS_MAJOR    240
#define IICBUSRAW_MINOR	1

#define IICBUS_INT	INT_IIC

static char *IICBUD_id = "SKQ IICBUS driver v1.0 (2005-06-02)<[e-mail]>";

/* debug macros */
#undef DEBUG
//#define DEBUG
#ifdef DEBUG
#define DPRINTK( x... )	printk("SKQ IICBUS: " ##x)
#else
#define DPRINTK( x... )
#endif


#define WRDATA	    (1)
#define POLLACK     (2)
#define RDDATA	    (3)
#define SETRDADDR   (4)

#define IICBUFSIZE 2048

char IICBUS_Buf[IICBUFSIZE];

static int opencount=0;
static int tsMajor = 0;
static loff_t newpos=0;
int WriteFM24CL16(char * buffer, size_t count,int address)
	{
	unsigned long timeo;
	U16 i;
	U16 PageAdd;
	char slvAddr,tempIICCON,tempIICSTAT;
	IICCON=(1<<7)|(0<<6)|(1<<5)|(0xf);
	IICSTAT=0x10;
	
	slvAddr=0xa0;
	PageAdd=address;
	/*发送起始位和设备地址和页地址*/
	PageAdd>>=7;
	PageAdd&=0x0e;
	slvAddr=(char )PageAdd;
	slvAddr|=0xa0;
	IICDS=slvAddr;//0xa0
  	IICSTAT=0xf0; //MasTx,Start	
  
  timeo = jiffies + (HZ/100);
  while(1)
  	{
  	tempIICCON=IICCON;
  	tempIICCON&=0x10;	/*pending*/
  	tempIICSTAT=IICSTAT;
  	tempIICSTAT&=0x01;/*ack*/
  	if((tempIICCON==0x10)) break	;//&&(tempIICSTAT==0x00)
  	if(time_after(jiffies, timeo))
  		{
  			IICSTAT=0xd0; 
  			IICCON=0xaf;
  			udelay(200);
  			IICCON=0xaf;
				IICSTAT=0x10;
  			 return -1;
  			}
  	};
  IICCON=0xaf;/*clr pending*/
  
  IICDS=(char )address;//0xa0
  timeo = jiffies + (HZ/100);
  while(1){
  	tempIICCON=IICCON;
  	tempIICCON&=0x10;	
  	tempIICSTAT=IICSTAT;
  	tempIICSTAT&=0x01;
  	if((tempIICCON==0x10)) break	;//&&(tempIICSTAT==0x00)
  	if(time_after(jiffies, timeo)) 
  		{
  			IICSTAT=0xd0; 
  			IICCON=0xaf;
  			udelay(200);
  			IICCON=0xaf;
				IICSTAT=0x10;
  			 return -1;
  			}
  	};
  IICCON=0xaf;
  
  for(i=0;i<count;i++)
  	{
  	IICDS=buffer[i];
  	timeo = jiffies + (HZ/100);
  	while(1){
  		tempIICCON=IICCON;
  		tempIICCON&=0x10;	
  		tempIICSTAT=IICSTAT;
  		tempIICSTAT&=0x01;
  		if((tempIICCON==0x10)&&(tempIICSTAT==0x00)) break	;
  		if(time_after(jiffies, timeo))
  			{
  			IICSTAT=0xd0; 
  			IICCON=0xaf;
  			udelay(200);
  			IICCON=0xaf;
				IICSTAT=0x10;
  			 return -1;
  			}
  		};
  	IICCON=0xaf;/*clr pending*/	
  	}
  IICSTAT=0xd0; 
  IICCON=0xaf;
  udelay(200);
  IICCON=0xaf;
IICSTAT=0x10;
	return count;		
	}

int ReadFM24CL16(char * buffer, size_t count,int address)
	{
	unsigned long timeo;
	U16 i;
	U8 slvAddr,tempIICCON,tempIICSTAT;
	U16 PageAdd;
	PageAdd=address;
	/*发送起始位和设备地址和页地址*/
	PageAdd>>=7;
	PageAdd&=0x0e;
	slvAddr=(char )PageAdd;
	slvAddr|=0xa0;
	IICDS=slvAddr;//0xa0
  IICSTAT=0xf0; //MasTx,Start	
  timeo = jiffies + (HZ/100);
  while(1){
  	tempIICCON=IICCON;
  	tempIICCON&=0x10;	
  	//tempIICSTAT=rIICSTAT;
  	//tempIICSTAT&=0x01;
  	if((tempIICCON==0x10)) break	;//&&(tempIICSTAT==0x00)
  	if(time_after(jiffies, timeo))
  		{
  			IICSTAT=0x90; 
  			IICCON=0xaf;
  			udelay(200);
  			IICCON=0xaf;
				IICSTAT=0x10;
				return -1;
  		}
  	};
  IICCON=0xaf;
  /*发送地址低8位*/
  IICDS=(char )address;
  timeo = jiffies + (HZ/100);
  while(1){
  	tempIICCON=IICCON;
  	tempIICCON&=0x10;	
  	tempIICSTAT=IICSTAT;
  	tempIICSTAT&=0x01;
  	if((tempIICCON==0x10)) break	;//&&(tempIICSTAT==0x00)
  	if(time_after(jiffies, timeo))
  		{
  			IICSTAT=0x90; 
  			IICCON=0xaf;
  			udelay(200);
  			IICCON=0xaf;
				IICSTAT=0x10;
				return -1;
  		}
  	};
  IICCON=0xaf;
  //IICSTAT&=0xef; 
  /*发送起始位和设备地址和页地址*/
  PageAdd>>=7;
	PageAdd&=0x0e;
	slvAddr=(char )PageAdd;
	slvAddr|=0xa1;
  IICDS=slvAddr;
  IICSTAT=0xb0;//MasRx,Start
  timeo = jiffies + (HZ/100);
  while(1){
  	tempIICCON=IICCON;
  	tempIICCON&=0x10;	
  	tempIICSTAT=IICSTAT;
  	tempIICSTAT&=0x01;
  	if((tempIICCON==0x10)) break	;//&&(tempIICSTAT==0x00)
  	if(time_after(jiffies, timeo))
  		{
  			IICSTAT=0x90; 
  			IICCON=0xaf;
  			udelay(200);
  			IICCON=0xaf;
				IICSTAT=0x10;
				return -1;
  		}
  	};
  IICCON=0xaf;
  
  for(i=0;i<count;i++)
  	{
		IICDS=slvAddr;
  	//timeo = jiffies + (HZ/100);
   while(1){
  	tempIICCON=IICCON;
  	tempIICCON&=0x10;	
  	tempIICSTAT=IICSTAT;
  	tempIICSTAT&=0x01;
  	if((tempIICCON==0x10)) break	;//&&(tempIICSTAT==0x00)
  	//else
  	//	{
  	//	if((tempIICCON==0x10)&&(i==count-1) ) break	;
  	//	}
  	if(time_after(jiffies, timeo))
  		{
  			IICSTAT=0x90; 
  			IICCON=0xaf;
  			udelay(200);
  			IICCON=0xaf;
				IICSTAT=0x10;
				return -1;
  		}
  	};
  buffer[i]=IICDS;	
  if(i==count-1) IICCON=0x2f;
  else  IICCON=0xaf;	
  
  
  	}
  	
  IICSTAT=0x90; 
  IICCON=0xaf;
  udelay(200);
  IICCON=0xaf;
	IICSTAT=0x10;
	
	return count;		
	}

loff_t IICBUS_llseek(struct file *filp, loff_t off, int whence)
{
    
    

    switch(whence) {
      case 0: /* SEEK_SET */
        newpos = off;
        break;
      default: /* can't happen */
        return -EINVAL;
    }
    if (newpos<0) return -EINVAL;
    return newpos;
}
	
static ssize_t IICBUS_write(struct file *file, const char *buffer, size_t count, loff_t * ppos)
{
	
	int ret;
	int address=(int)newpos;
	if(count>2048) return 0;
	///copy_from_user(&address, ppos, sizeof(loff_t));
	//address=(int )*ppos;
	//printk("IICBUS_write address=%ld\n",address);
	if(address+count>2048) return 0;
	copy_from_user(IICBUS_Buf,buffer, count);
	ret=WriteFM24CL16(IICBUS_Buf, count,address);
	return ret;

}
static ssize_t IICBUS_read(struct file *filp, char *buffer, size_t count, loff_t *ppos)
{
	
	int len;
	int address=(int)newpos;
	//int address1;
	if(count>2048) return 0;
	//copy_from_user(&address, ppos, sizeof(loff_t));
	//address=(int )*ppos;
	//printk("IICBUS_read address=%d\n",address);
	if(address+count>2048) return 0;
	//address1=(int)*ppos;
	//printk("IICBUS_read address1=%ld\n",address);
	//printk("IICBUS_read ppos=%ld\n",ppos);
	len=ReadFM24CL16(IICBUS_Buf, count,address);
	copy_to_user(buffer,IICBUS_Buf,len);
	DPRINTK("read data=%d\n", data);
	return len;

}
static int IICBUS_open(struct inode *inode, struct file *file)
{
	//if(opencount==1)
	//	return -EBUSY;
	opencount++;
	MOD_INC_USE_COUNT;
	DPRINTK("device open\n");
	return 0;
}

static int IICBUS_release(struct inode *inode, struct file *filp)
{
	opencount--;
	MOD_DEC_USE_COUNT;
	DPRINTK("device release\n");
	return 0;
}
static struct file_operations s3c44b0_iicbus_fops  = {
	owner:	THIS_MODULE,
	llseek: IICBUS_llseek,
	write:	IICBUS_write,	
	read:		IICBUS_read,	
	open:		IICBUS_open,
	release:IICBUS_release,
};

static int __init IICBUS_init(void)
{
	int ret;
	int flags;
	local_irq_save(flags);
	/* Port F */
	/*  Bit8	7		6		5		 4		3		2		1		0		*/   
	/*  SPICLK	SPIMISO		SPICS		SPIMOSI		INCARD2		NC		NC		IICSDA		IICSCL	*/
    	PCONF |=0x0a;	//PF0:IICSCL, PF1:IICSDA
    	PUPF |=0x03;	//pull-up disable
    	IICCON=(1<<7)|(0<<6)|(0<<5)|(0xf);
    	//Enable interrupt, IICCLK=MCLK/16, Enable ACK
    	//40Mhz/16/(15+1) = 257Khz	
    	IICADD=0x10;   // S3C44B0X slave address
    	IICSTAT=0x10;
	local_irq_restore(flags);
	opencount=0;
	ret = register_chrdev(IICBUS_MAJOR, SKQ_IIC_MODULE_NAME, &s3c44b0_iicbus_fops);
	if (ret < 0) {
	  printk(__FUNCTION__ ": can't get major number\n");
        return -1;
	}
	tsMajor = ret;
#if 0	
if ( 0 != request_irq(IICBUS_INT, IICBUS_isr ,SA_INTERRUPT,IICBUD_id, NULL)) 
   {
	printk(KERN_WARNING "tce44b0_usb: failed to get IRQ\n");
	return 1;
   }
#endif   
#ifdef CONFIG_DEVFS_FS
	devfs_iic_dir = devfs_mk_dir(NULL, SKQ_IIC_MODULE_NAME, NULL);
	devfs_iicraw = devfs_register(devfs_iic_dir, "0", DEVFS_FL_DEFAULT,
			tsMajor, IICBUSRAW_MINOR, S_IFCHR | S_IRUSR | S_IWUSR,
			&s3c44b0_iicbus_fops , NULL);
#endif
	printk(SKQ_IIC_MODULE_NAME " initialized\n");
	return 0;
}

static void __exit IICBUS_exit(void)
{

	printk(__FUNCTION__ ": SKQ IIC Exit.\n");
  	free_irq(IICBUS_INT,IICBUD_id);
	devfs_unregister_chrdev(IICBUS_MAJOR, SKQ_IIC_MODULE_NAME );
}
module_init(IICBUS_init);
module_exit(IICBUS_exit);
MODULE_DESCRIPTION("SKQ IIC driver");
MODULE_AUTHOR("pengshicao <[e-mail]>");
MODULE_LICENSE("GPL");