嵌入式家庭网关中SPI接口的软件模拟

return-EFAULT;

for(num=0;num<count;num++){

for(i=0;i<8;i++){

iopdata=((SPI_write[num]&0x1)<<11)+(iopdata&0xfffff7ff);

SPI_write[num]=SPI_write[num]>>1;

iopdata=iopdata^0x1000; //时钟输出

}

}

return count;

}

//中断响应函数

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

{

intpnd=intpnd|0X1; //清中断位

wake_up_interruptible(&SPI_wait); //唤醒睡眠队列

return

}

//字符设备驱动接口

static struct file_operations SPI_fops={

owner; THIS_MODULE,

read: SPI_onlyread,

write: SPI_onlywrite,

};

//初始化函数

int_init SPI_init(void)

register_chrdev(29,"SPI"&SPI_fops);//设备注册函数

init_waitqueue_head(&SPI_wait);

if(!request_irq(0,SPI_irq,SA_SAMPLE_RANDOM,"SPI"NULL)){ //中断申请

return-EFAULT;

}

iopmod=(iopmod&0xffffe7ff)=0x1800+iopmod; //设置通用I/O口模式

iopcon=(iopcon&0xffffffe0)+0xle+iopcon;//设置通用I/O模式

enable_irq(0); //开中断

return 0;

}

module_init(SPI_init);

MODULE_LICENSE("GPL);

EXPORT_NO_SYMBOLS;