9260EK-linux-KEY测试(查询)

KEY测试(查询)

作好了LED，现在做一个按键，板子的按键是接在PIOB0-3，只需要稍微改动一下就可以了，程序如下

#include

#include

#include

#include

#include

#include /* get the user-level API */

#include

#include

#include

#include

#include "at91_pio.h"

MODULE_LICENSE("GPL");

static void __iomem *pio_base;

size_t key_read (struct file *filp, char __user *buf, size_t count, loff_t *pos){

      printk("watchdog read.\r\n");

      return 0;

}

ssize_t key_write (struct file *filp, const char __user *buf, size_t count,off_t *pos){

      printk("watchdog write.\r\n");

      return count;

}

int key_ioctl (struct inode *inode, struct file *filp,unsigned int cmd, unsigned long arg){

      arg=readl(pio_base + PIO_PDSR)&0x0000000f;

      //printk("led ioctl cmd:%d%ld\r\n",cmd,arg);

      return arg;

}

static struct file_operations key_fops = {

      .owner = THIS_MODULE,

      .read   = key_read,

      .write = key_write,

      .ioctl = key_ioctl,

};

static int key_init(void){

      int result;

      printk(KERN_ALERT "key_test:%s,%s\r\n",__DATE__,__TIME__);

      pio_base = ioremap(0xFFFFF600,512);       

      writel(0x0000000f, pio_base + PIO_PUER);    

      writel(0x0000000f, pio_base + PIO_PER);     

      writel(0x0000000f, pio_base + PIO_IDR);

     

      result = register_chrdev(61, "key", &key_fops);

      if (result < 0){

          printk("register device fail.\r\n");

return result;

      }

      return 0;

}

static void key_exit(void){

printk("stop key\r\n");

      unregister_chrdev(61, "key");

      iounmap(pio_base);

      printk(KERN_ALERT "stop clear key\r\n");

}

module_init(key_init);

module_exit(key_exit);

同样编译好后，在运行之前，先要创建一个设备文件

# mknod "/dev/led" c 61 1

即创建一个主设备号为61，次设备号为1名称为KEY的字符型设备。

然后运行这个函数，按下按键，即可看见终端会有相应的显示。