nnrf2401.c

组网协议设计中

#include<linux/module.h>
#include<linux/init.h>
#include<linux/kernel.h>
#include<linux/config.h>
#include<linux/fs.h>
#include<asm/uaccess.h>
#include<linux/version.h>
#include<linux/irq.h>
#include<linux/poll.h>
#include<linux/delay.h>
#include<asm/arch/irq.h>
#include<asm/hardware.h>
#include<linux/spinlock.h>
#include<asm/arch/S3C2440.h>   //为了使用GPIO端口定义
#include<linux/devfs_fs_kernel.h> //为了使用devfs_register和devfs_unregister函数
MODULE_LICENSE("GPL");

#define DEVICE_NAME "nRF2401"
#define MAJOR_NUM 233
#define MINOR_NUM 0

static devfs_handle_t devfs_handle=NULL;
static devfs_handle_t devfs_nRF2401_dir=NULL; //在/dev下建立相应的目录
#define DEV_DIR "nRF2401" 

static DECLARE_WAIT_QUEUE_HEAD(nRF2401_wait); 
static int ready=0;                            

#define DR1     GPIO_G9                  //定义GPIO口与NRF2440的接口
#define PWR_UP  GPIO_B6
#define CLK1    GPIO_G7
#define MISO    GPIO_G5
#define MOSI    GPIO_G6
#define CE      GPIO_E13
#define CS      GPIO_E12
#define LED     GPIO_F4

#define PACKETLEN 22
unsigned char RData[PACKETLEN];  //指向驱动程序申请的用于存放接收数据的内存区域

static struct nRF2401Config{
	unsigned char n; //配置字长度
	unsigned char buf[15];//配置字数组
}config={15,
        {
	  0x00,			//接收通道2有效数据长度
          0xB0,			//接收通道1有效数据长度		
          0x00,0x00,0x00,0x00,0x00,  //接收通道2地址,最长5字节,缺少位用0填
          0x00,0xcc,0xcc,0xcc,0xcc,	//接收通道1地址,最长5字节,缺少位用0填
          0x83,                //32位地址长度(bit7-bit2);16bit CRC(bit1);CRC enable
          0x4f,//单通道接收(bit7);ShockBrust(bit6);速率(bit5);晶振频率(bit4-bit2);功率(bit2-bit0)
          0x01		//频道(bit7-bit1);发送/接收(bit0:0/1)
	}
       };
static void SPI_init(void){
	//IO initial
	set_gpio_ctrl(DR1|GPIO_MODE_ALT0);//设置为DR1为中断模式
	set_gpio_ctrl(CE|GPIO_MODE_OUT|GPIO_PULLUP_EN);
	set_gpio_ctrl(CS|GPIO_MODE_OUT|GPIO_PULLUP_EN);
	set_gpio_ctrl(PWR_UP|GPIO_MODE_OUT|GPIO_PULLUP_EN);
	set_gpio_ctrl(CLK1|GPIO_MODE_ALT1|GPIO_PULLUP_EN);//设置引脚为SPI
	set_gpio_ctrl(MISO|GPIO_MODE_ALT1|GPIO_PULLUP_EN);
	set_gpio_ctrl(MOSI|GPIO_MODE_ALT1|GPIO_PULLUP_EN);
	
	set_gpio_ctrl(LED|GPIO_MODE_OUT|GPIO_PULLUP_EN);//设置LED引脚
	write_gpio_bit(PWR_UP,0);//初始化nFR2401引脚
	write_gpio_bit(CE,0);
	write_gpio_bit(CS,0);
	write_gpio_bit(LED,1);//关LED
	
	//REGISTER initial
	SPPRE1=0xff; //设置波特率为132,300bps
	SPCON1=0x18;//设置为查询方式
	printk("SPI configured\n");
	}
	
static void SPI_poll_done(void){
	int ncount=0;
	while(!(SPSTA1&0x01)){    //判断SPI发送寄存器是否已经准备好
		ncount++;
		if(ncount>=5000){
			printk("SPI state poll failed\n");
		//	return -1;
			break;
			}
			}
		//return 0;
		}
static void SPI_tx_data(unsigned char data){                //通过SPI发送数据
	SPI_poll_done();
	SPTDAT1=data;
	SPI_poll_done();
	}
	
void RX_Packet(void)						
{					//读取数据包
	unsigned char i;
	for(i=0;i<PACKETLEN;i++)
	{
		SPI_tx_data(0xff);
		RData[i]=SPRDAT1;
		}
	printk("recevie RX_Packet\n");
}		

static void nRF2401_ON(void) 
{	                                //nRF2401上电
	write_gpio_bit(CE,0);
	write_gpio_bit(CS,0);
	write_gpio_bit(PWR_UP,1);
	mdelay(3);//延时3ms,nrf2401进入待机模式
	printk("nRF2401 on\n");
}
static void nRF2401_Config(void)
{                                   //nRF2401配置
	unsigned char i;
	write_gpio_bit(CE,0);
	write_gpio_bit(CS,1);
	udelay(10);   //延时10us
	for(i=0;i<config.n;i++){
		SPI_tx_data(config.buf[i]);
		}
	write_gpio_bit(CS,0);
	write_gpio_bit(CE,1);//激活接收模式,经过202us内部延时后进入接收模式
	printk("nRF2401 configed\n");
}

static void nRF2401_Close(void)//关闭nRF2401
{
	write_gpio_bit(CE,0);
	write_gpio_bit(CS,0);
	write_gpio_bit(PWR_UP,0);
	printk("nRF2401 close\n");
}	

static void nRF2401_irq(int irq,void *dev_id,struct pt_regs *reg)
{       
	unsigned int flags;
	write_gpio_bit(LED,0);//开LED,表示接收到数据
	save_flags(flags); //中断处理时禁止再次中断
	cli();
	//printk("nRF2401have prepared the datas!\n");     //中断处理函数
	//mdelay(1000);
	RX_Packet();	
	restore_flags(flags);	
	write_gpio_bit(LED,1);//关LED,表示读完数据
	ready=1;
	wake_up_interruptible(&nRF2401_wait); //通知应用程序有数据可读
	
}

static int requestb_irq(void)   //中断申请函数
{ 
	set_external_irq(IRQ_EINT17,EXT_RISING_EDGE,GPIO_PULLUP_DIS);//DR1上升沿触发
	if(request_irq(IRQ_EINT17,&nRF2401_irq,SA_INTERRUPT,DEVICE_NAME,&nRF2401_irq)){
		printk(DEVICE_NAME" request_irq failed!\n");
		return -1;
		}
	printk("irq succes!\n");
	return 0;
}
static void freeb_irq(void)
{
	free_irq(IRQ_EINT17,nRF2401_irq);
	
}
static int nRF2401_open(struct inode *inode,struct file *file)
{
	ready=0;
	nRF2401_ON();
	nRF2401_Config();
   printk(DEVICE_NAME" open\n");
   MOD_INC_USE_COUNT;
   return 1;
   }
static int nRF2401_release(struct inode *inode,struct file *file)
{	nRF2401_Close();
   printk(DEVICE_NAME" release\n");
   
   MOD_DEC_USE_COUNT;
   return 1;
   }

static ssize_t nRF2401_read(struct file *file,char *buf,size_t len,loff_t *off)
{
   	
  	__copy_to_user(buf,RData,sizeof(RData));
  	ready=0; 
  	return sizeof(RData);
}
/*static ssize_t nRF2401_write(struct file *file,const char *buf,size_t len,loff_t *off)
{
	__copy_from_user(&,buf,sizeof());
	return sizeof();
}*/
static  unsigned int nRF2401_select(struct file *file,struct poll_table_struct *wait)
{	//printk("poll ready is%d\n",ready);
	
	if(ready)return 1;
	poll_wait(file,&nRF2401_wait,wait);//使外部应用程序阻塞,等待数据准备好
	return 0;
}
static struct file_operations nRF2401_fops={
 owner: THIS_MODULE,
 open:nRF2401_open,
 release:nRF2401_release,
 //ioctl:nRF2401_ioctl,
 read:nRF2401_read,
// write:nRF2401_write,
 poll:nRF2401_select,
 };
 static int nRF2401_init(void)
{
    int ret;
    ret=register_chrdev(MAJOR_NUM,DEVICE_NAME,&nRF2401_fops);
    if(ret)
    {
    printk(DEVICE_NAME" register failure\n");
    return ret;
    }
    else
    printk(DEVICE_NAME" register success\n");
     ret=requestb_irq();
    if(ret){
    	ret=unregister_chrdev(MAJOR_NUM,DEVICE_NAME);
    	 if(ret)
   		 {
    		printk(DEVICE_NAME" unregister failure\n");
   		 }
   	 else printk(DEVICE_NAME" unregister success\n");
    	return ret;
    	}
    devfs_nRF2401_dir=devfs_mk_dir(NULL,DEV_DIR,NULL);
    devfs_handle=devfs_register(devfs_nRF2401_dir,DEVICE_NAME,DEVFS_FL_DEFAULT,MAJOR_NUM,MINOR_NUM,S_IFCHR|S_IRUSR|S_IWUSR,&nRF2401_fops,NULL);
    SPI_init();
    return ret;
}
static void nRF2401_exit(void)
{   
    int ret;
    devfs_unregister(devfs_handle);
    freeb_irq();
    ret=unregister_chrdev(MAJOR_NUM,DEVICE_NAME);
    if(ret)
    {
    printk(DEVICE_NAME" unregister failure\n");
    }
    else
    printk(DEVICE_NAME" unregister success\n");
    
    
}  
module_init(nRF2401_init);
module_exit(nRF2401_exit);