2440 iic 驱动

将一个组中的数据[/u]写入到AT24C02中,然后再读出来!

以下为DOME程序!

#include <stdio.h>

#include <fcntl.h>

#include <unistd.h>

#define
DEV_NAME
"/dev/2402_RW"

int main()

{ int fd,ret,i;

int
wr_data[5]={0x00,0x10,0x30,0x70,0xf0};

int ra_data[5];

fd=open(DEV_NAME,O_RDWR);

if (fd<0)

{ printf ("the derive is
opened fail !!\n");

return fd;

}

else

{ printf
("the derive is opened success !!\n");

write(fd,wr_data,sizeof(wr_data));

for(i=0;i<5;i++)

{ printf ("write-----data=%x\n",wr_data[i]);

}

sleep(2);

read(fd,ra_data,20);

for
(i=0;i<5;i++)

{ printf
("read------data=%x\n",ra_data[i]);

}

}

ret=close(fd);

printf ("the
ret=%d\n",ret);

}

以下为驱动[/u]源码!

#include <linux/kernel.h>

#include <linux/config.h>

#include <linux/init.h>

#include <linux/module.h>

#include <linux/fs.h>

#include
<linux/devfs_fs_kernel.h>

#include <linux/delay.h>

#include
<linux/interrupt.h>

#include
<asm-generic/errno-base.h>

#include
<asm/arch-s3c2410/regs-gpio.h>

#include
<asm/arch-s3c2410/regs-iic.h>

#include
<asm/arch-s3c2410/irqs.h>

#include <asm/hardware.h>

#include <asm/io.h>

#include <asm/uaccess.h>

#define DEV_ID 107

#define DEV_NAME
"2402_RW"

#define IICCON
0x54000000

#define IICSTAT 0x54000004

#define IICDS
0x5400000c

#define IICADD
0x54000008

#define IICLC
0x54000010

#define CLKCON
0x4c00000c

static void *S3C2402_IICSTAT;

static void *S3C2402_IICCON;

static void *S3C2402_IICDS;

static void *S3C2402_IICADD;

static void *S3C2402_IICLC;

static void *S3C2440_CLKCON;

static int wr_data[5];

static int ra_data[5];

static int ack=0;

void delay(int t)

{ int i;

for(;t>0;t--)

{
for(i=0;i<20000;i++);

}

}

static int open_2402(struct inode * inode, struct file *
file)

{ int cmmd;

writel(0xc0000,S3C2410_GPEUP);

s3c2410_gpio_cfgpin(S3C2410_GPE14,S3C2410_GPE14_IICSCL);

s3c2410_gpio_cfgpin(S3C2410_GPE15,S3C2410_GPE15_IICSDA);

S3C2402_IICCON=ioremap(IICCON,0x00000004);

S3C2402_IICSTAT=ioremap(IICSTAT,0x00000004);

S3C2402_IICDS=ioremap(IICDS,0x00000004);

S3C2402_IICADD=ioremap(IICADD,0x00000004);

S3C2402_IICLC=ioremap(IICLC,0X00000004);

S3C2440_CLKCON=ioremap(CLKCON,0x00000004);

writel(0xf3eb70,S3C2440_CLKCON);

cmmd=((S3C2410_IICCON_ACKEN)|(S3C2410_IICCON_TXDIV_16)|(S3C2410_IICCON_IRQEN)|(0x0f));

writel(cmmd,S3C2402_IICCON);

writel(0x10,S3C2402_IICADD);

writel(0x10,S3C2402_IICSTAT);

writel((S3C2410_IICLC_FILTER_ON|S3C2410_IICLC_SDA_DELAY5),S3C2402_IICLC);

return 0;

}

static int write_2402(struct file * file, const
char __user * userbuf,size_t count, loff_t * off)

{ int i;

ack=0;

if(copy_from_user(wr_data,userbuf,count)!=0)

{ printk("write is error!!\n");

return EFAULT;

}

writel(0xa0,S3C2402_IICDS);

writel(0xf0,S3C2402_IICSTAT);

udelay(100);

while(ack==0);

ack=0;

writel(0x00,S3C2402_IICDS);

writel(0xaf,S3C2402_IICCON);

udelay(100);

while(ack==0);

ack=0;

for(i=0;i<5;i++)

{

writel(wr_data[i],S3C2402_IICDS);

printk("wr_data=%x\n",wr_data[i]);

writel((readl(S3C2410_GPFDAT)|wr_data[i]),S3C2410_GPFDAT);

writel(0xaf,S3C2402_IICCON);

udelay(100);

while(ack==0);

printk("ack=%x\n",ack);

ack=0;

}

writel(0xd0,S3C2402_IICSTAT);

writel(0xaf,S3C2402_IICCON);

udelay(100);

return count;

}

static int read_2402 (struct file * file, char
__user * userbuf, size_t count, loff_t * off)

{ int i,a;

ack=0;

writel(0xa0,S3C2402_IICDS);

writel(0xf0,S3C2402_IICSTAT);

udelay(100);

while(ack==0);

ack=0;

writel(0x00,S3C2402_IICDS);

writel(0xaf,S3C2402_IICCON);

udelay(100);

while(ack==0);

ack=0;

writel(0xa1,S3C2402_IICDS);

writel(0xb0,S3C2402_IICSTAT);

writel(0xaf,S3C2402_IICCON);

udelay(100);

a=readl(S3C2402_IICDS);

printk("a=%x\n",a);

for (i=0;i<5;i++)

{
while(ack==0);

printk("ack=%x\n",ack);

ack=0;

writel(0xaf,S3C2402_IICCON);

udelay(100);

ra_data[i]=readl(S3C2402_IICDS);

writel((readl(S3C2410_GPFDAT)|ra_data[i]),S3C2410_GPFDAT);

printk("ra_data=%x\n",ra_data[i]);

}

writel(0x90,S3C2402_IICSTAT);

writel(0xaf,S3C2402_IICCON);

udelay(100);

if(copy_to_user(userbuf,ra_data,count)!=0)

{
printk("read is error!!\n");

return EFAULT;

}

return count;

}

static irqreturn_t iic_interrupt(int irq,void *dev_id,struct
pt_regs *regs)

{

ack=1;

return IRQ_HANDLED;

}

static struct file_operations test_2402 ={

.open
= open_2402,

.write
= write_2402,

.read =
read_2402,

};

static int __init init_2402(void)

{ int result,ret;

result=register_chrdev(DEV_ID,DEV_NAME,&test_2402);

if (result<0)

{ printk ("the derive register
is fail!!!\n");

return
ENODEV;

}

else

{ printk ("the derive register
is succss!!!\n");

ret=request_irq(IRQ_IIC,&iic_interrupt,SA_INTERRUPT,DEV_NAME,&iic_interrupt);

if(ret<0)

{ printk("the iic_interrupt is requestted
fail\n");

return ENODEV;

}

else

{ printk("the iic_interrupt is requestted
sccuss!!\n");

devfs_mk_cdev(MKDEV(DEV_ID,0),S_IFCHR | S_IRUSR |
S_IWUSR,"2402_RW");

return
ret;

}

return
result;

}

}

static void __exit exit_2402(void)

{ unregister_chrdev(DEV_ID,DEV_NAME);

disable_irq(IRQ_IIC);

free_irq(IRQ_IIC,&iic_interrupt);

devfs_remove(DEV_NAME);

printk ("the derive is unregister\n");

}

module_init(init_2402);

module_exit(exit_2402);

MODULE_LICENSE("GPL");

MODULE_AUTHOR("KANG");

MODULE_DESCRIPTION("2402_READ_WRITE");