Драйвер под ARM-систему работает частично

#include <linux/fs.h>            /* everything... */
#include <mach/regs-gpio.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/ioctl.h>
#include <linux/cdev.h>
#include <linux/gpio.h>
#include <asm/uaccess.h>
#include <asm/unistd.h>
 
 
#define DEVICE_NAME "mini2440_buttons"
#define NUM_OF_LEDS 4
 
 
int minor_num=0;
int major_num=0;
 
 
struct cdev cdev;     /* Char device structure      */
 
static unsigned long button_table []={
    S3C2410_GPG0_EINT8,
    S3C2410_GPG3_EINT11,
    S3C2410_GPG5_EINT13,
    S3C2410_GPG6_EINT14,
};
 
static unsigned long led_table [] = {
    S3C2410_GPB(5),
    S3C2410_GPB(6),
    S3C2410_GPB(7),
    S3C2410_GPB(8),
};
 
static unsigned int led_cfg_table [] = {
    S3C2410_GPIO_OUTPUT,
    S3C2410_GPIO_OUTPUT,
    S3C2410_GPIO_OUTPUT,
    S3C2410_GPIO_OUTPUT,
};
 
 
static int sbc2440_leds_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
{
    int i,j, pin_status=999, button_flag[4]={0}, led_flag[4]={0};
 
    printk(KERN_WARNING "cmd is %d\n",cmd);
    if(cmd==1){
        for(j=1; j<=200; j++){
            for(i=0;i<=3;i++){
                pin_status = !s3c2410_gpio_getpin(button_table[i]);
                printk(KERN_WARNING "button %d pin_status %d\n",i+1,pin_status);
                if(pin_status==1 && button_flag[i]==0){  // button pressed
                    s3c2410_gpio_setpin(led_table[i], 0); // led on
                    button_flag[i]=1;
                    led_flag[i]=1;
                    printk(KERN_WARNING "led %d turned on \n",i+1);
                }
                if(pin_status==1 && button_flag[i]==1){
                    s3c2410_gpio_setpin(button_table[i], 1); // button of
                    button_flag[i]=0;
                }
                if(pin_status==1 && led_flag[i]==1){
                    s3c2410_gpio_setpin(led_table[i], 1); // led of
                    led_flag[i]=0;
                    printk(KERN_WARNING "led %d turned off \n",i+1);
                }
            }
        }
        return 0;
    }
}
/************************************************************************************************************************/
//static struct file_operations dev_fops = {
struct file_operations dev_fops = {
 
    .owner  =   THIS_MODULE,
    .ioctl  =   sbc2440_leds_ioctl,
};
/************************************************************************************************************************/
/*
 * Set up the char_dev structure for this device.
 */
static void setup_cdev(void)
{
    int err, devno = MKDEV(major_num, minor_num);
    
    cdev_init(&cdev, &dev_fops);
    cdev.owner = THIS_MODULE;
    cdev.ops = &dev_fops;
    err = cdev_add (&cdev, devno, 1);
    /* Fail gracefully if need be */
    if (err)
        printk(KERN_NOTICE "Error adding char device err=%d", err);
}
/************************************************************************************************************************/
static int __init dev_init(void)
{
    int result;
    dev_t dev = 0;
    int i;
 
    printk(KERN_NOTICE "init_module():  major =  %d\n dont have a major so ask the o.s. for one\n", major_num);
    result = alloc_chrdev_region(&dev, minor_num, 1,DEVICE_NAME);
    if (result < 0) 
    {
        printk(KERN_WARNING "init_module(): REGISTRATION FAILURE %d\n", major_num);
        goto fail;  // Make this more graceful 
    }
    
    major_num = MAJOR(dev);
    printk(KERN_NOTICE "init_module():  the o.s. gave us major =  %d\n", major_num);
 
 
    /* Initialize the char device. */
    setup_cdev();
    
    //configure the pins as GPIO output and init them to be off on startup
    for (i = 0; i < NUM_OF_LEDS; i++) {
        s3c2410_gpio_cfgpin(led_table[i], led_cfg_table[i]);
        s3c2410_gpio_setpin(led_table[i], 1);
        s3c2410_gpio_setpin(button_table[i], 1);
    }
 
    printk (DEVICE_NAME"\t Device initialized\n");
 
    return result;
 
fail:
    unregister_chrdev_region(MKDEV(major_num, minor_num), 1);
    return -EFAULT;
}
/**********************************************************************/
static void __exit dev_exit(void)
{
    dev_t devno = MKDEV(major_num, minor_num);
    
    /* Get rid of our char dev entries */
    cdev_del(&cdev);
    
    /* cleanup_module is never called if registering failed */
    unregister_chrdev_region(devno, 1);
    
    printk(KERN_NOTICE "char device unregistered");
    printk(KERN_NOTICE "char device module unloaded");
 
    
}
/**********************************************************************/
module_init(dev_init);
module_exit(dev_exit);
MODULE_LICENSE("GPL");

static unsigned int button_cfg_table [] = {
    S3C2410_GPIO_INPUT,
    S3C2410_GPIO_INPUT,
    S3C2410_GPIO_INPUT,
    S3C2410_GPIO_INPUT,
};

s3c2410_gpio_cfgpin(button_table[i], button_cfg_table[i]);