keybutton.c

linux2.6下一个4x4的键盘驱动源码

/*--------------------------------------------------------------
  4X4键盘使用中断号IRQ_EINT4, IRQ_EINT5, IRQ_EINT6, IRQ_EINT7
  4X4键盘行输入线：S3C2410_GPF4, S3C2410_GPF5,S3C2410_GPF6, S3C2410_GPF7（与中断号分别对应）
  4X4键盘列扫描线：S3C2410_GPG0, S3C2410_GPG2, S3C2410_GPG8, S3C2410_GPG9

--------------------------------------------------------------*/  
#include <linux/config.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/errno.h>

#include <linux/miscdevice.h>
#include <asm/uaccess.h> /*copy user*/
#include <linux/sched.h>
#include <linux/delay.h>
#include <linux/poll.h>
#include <linux/spinlock.h>

#include <asm/io.h>
#include <asm-arm/arch-s3c2410/irqs.h>
#include <asm-arm/irq.h>
#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <linux/wait.h>
//#include <linux/irq.h>

#include <linux/cdev.h>
#include <linux/delay.h>
#include <linux/devfs_fs.h>
#include <linux/devfs_fs_kernel.h>

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

#define DEVICE_NAME	"keybutton"
#define BUTTON_MAJOR 234
#define BUTTON_MINOR 0
#define KBDSTATUS_UP    0
#define KBDSTATUS_DOWN  1
#define KBDSTATUS_DOWNX  2
static int kbd_status; //按键状态
static int irq_col_tab[] = { IRQ_EINT4, IRQ_EINT5, IRQ_EINT6, IRQ_EINT7};
#define COL_NUM ( (sizeof irq_col_tab) / sizeof (irq_col_tab[0]) )
static unsigned gpio_col_tab[] = {S3C2410_GPF4, S3C2410_GPF5,S3C2410_GPF6, S3C2410_GPF7};
static unsigned gpio_row_tab[] = {S3C2410_GPG0, S3C2410_GPG2, S3C2410_GPG8, S3C2410_GPG9 };
static unsigned gpio_row_out_tab[] = { S3C2410_GPG0_OUTP, S3C2410_GPG2_OUTP, S3C2410_GPG8_OUTP, S3C2410_GPG9_OUTP };
static unsigned key_scan_value[] = {0x001,0x004,0x100,0x200};
#define ROW_NUM ( sizeof gpio_row_tab / sizeof (gpio_row_tab[0]) )

static int ready = 0;
static int key_value = 0, last_value = 0;
int col_no, row_no,r;

unsigned int gpf_con,gpf_dat,gpf_up,gpg_con,gpg_dat,gpg_up,gpf_con1,gpg_con1,gpf_dat1,gpg_dat1;
static DECLARE_WAIT_QUEUE_HEAD(buttons_wait);

//static int waitting_down_tab[] = {1, 1, 1, 1,};
static void __iomem *gpbase;
//static void __iomem *addrpenda_map;
//static void __iomem *addrpendb_map;
static void scan_kbd(void);
static void kbd_timer_handler(void);
static int ISKBD_DOWN(void);
static int ISKBD_DOWN(void)
{
 int c1;
 gpf_con1=readl(gpbase+0x50) ; 
 gpf_dat1=readl(gpbase+0x54);
 gpg_con1=readl(gpbase+0x60) ;
 gpg_dat1=readl(gpbase+0x64);
 //printk("ISKBD_DOWN col_no= %d\n",col_no);
 if(col_no==0){
 	writel(gpf_con1 & 0xfcff,gpbase+0x50);
 	c1 = readl(gpbase+0x54) & 0x10;
 	writel((gpf_con1 | (2<<8)),gpbase+0x50) ;
  }
 else if(col_no==1){
 	writel(gpf_con1 & 0xf3ff,gpbase+0x50);
 	c1 = readl(gpbase+0x54) & 0x20;
 	writel((gpf_con1 | (2<<10)),gpbase+0x50) ;
  }
 else if(col_no==2){
 	writel(gpf_con1 & 0xcfff,gpbase+0x50) ;
 	c1 = readl(gpbase+0x54) & 0x40;
 	writel((gpf_con1 |(2<<12)),gpbase+0x50) ;
  }
 else if(col_no==3){
 	writel(gpf_con1 & 0x3fff,gpbase+0x50) ;
 	c1 = readl(gpbase+0x54) & 0x80;
 	writel((gpf_con1 |(2<<14)),gpbase+0x50) ;//F端口中F7管脚设为中断模式
  }
 else
 	return 0;	
 if(!c1)
   c1=1;
 else
   c1=0; 
 return c1;
} 

static void kbd_timer_handler(void)
{
 
 if(ISKBD_DOWN())
   {
   	//printk("key  socend test down\n");
   if(kbd_status == KBDSTATUS_DOWNX)  
   	{
   		kbd_status = KBDSTATUS_DOWN;
   		
      scan_kbd();
    }
 
    mdelay(100);
    kbd_timer_handler();
   }
 else{
   kbd_status = KBDSTATUS_UP;
  
  }
}
static void scan_kbd(void)
{
	   int i;
     //spin_lock_irq(&kbd);
     gpf_con=readl(gpbase+0x50) ;	  
     gpf_dat=readl(gpbase+0x54);
     gpf_up=readl(gpbase+0x58);
     gpg_con=readl(gpbase+0x60) ;
     gpg_dat=readl(gpbase+0x64);
     gpg_up=readl(gpbase+0x68);
     //printk("gpf_con=%x,gpf_up=%x,gpf_dat=%x.gpg_con+%x\n",gpf_con,gpf_up,gpf_dat,gpg_con);
     writel(gpf_con & 0x00ff,gpbase+0x50);
     writel(gpf_up | 0xf7,gpbase+0x58);
     //printk("gpf_con=%x,gpg_con=%x\n",readl(gpbase+0x50),readl(gpbase+0x60));
	   for (i = 0; i < 4; i++) 
	   {
			//unsigned char val = 0x10;
			//printk("scan row\n");
			writel((gpg_dat | (key_scan_value[i])),gpbase+0x64);
			udelay(100);
		  r= s3c2410_gpio_getpin(gpio_col_tab[col_no]);
			writel((gpg_dat & (~(key_scan_value[i]))),gpbase+0x64);
			udelay(100);
			if(r)
			  { // found
				  row_no = i;

				  break;
			  }
		  }
		  writel((gpf_con |(2<<2)|(2<<8)|(2<<10)|(2<<12)|(2<<14)),gpbase+0x50) ;
      udelay(100);
      set_irq_type(IRQ_EINT4,IRQT_LOW);
      set_irq_type(IRQ_EINT5,IRQT_LOW);
      set_irq_type(IRQ_EINT6,IRQT_LOW);
      set_irq_type(IRQ_EINT7,IRQT_LOW);
      //printk("gpf_con=%x,gpg_con=%x\n",readl(gpbase+0x50),readl(gpbase+0x60));	  
	    //spin_lock_irq(&kbd);
	    if (col_no < 0 || row_no < 0) 
	    {
	    	 mdelay(10);
	    	 kbd_timer_handler();
	    	 
	    }
	    key_value = row_no * 4 + col_no + 1;
	    //printk("kernel key_value=%d\n",key_value);
	    ready = 1;
	    wake_up_interruptible(&buttons_wait);
}

static irqreturn_t  buttons_irq(int irq, void *dev_id, struct pt_regs *reg)
{
	int i;
	unsigned long flags;
	col_no = -1; row_no = -1;
	//printk("interupt=%d\n",irq);
	for (i = 0; i < COL_NUM; i++) 
	{
		if (irq_col_tab[i] == irq) 
		{
			col_no = i;
			//printk("irq col= %d\n",i);
			break;
		}
	}
	if (col_no < 0)
  {
		goto EXIT;
	}
	//printk("kbd_status 0=%d\n",kbd_status);
 if(kbd_status == KBDSTATUS_UP) 
  {
  	//printk("key down\n");
    local_irq_save(flags); 
    //printk("ISKBD_DOWN=%d\n",ISKBD_DOWN());
   if(ISKBD_DOWN())       
    {
     //printk("key first test down\n");
     kbd_status = KBDSTATUS_DOWNX;
     
     mdelay(10);
    
     kbd_timer_handler();
    }
    else
    	local_irq_restore(flags);	
   }  
EXIT:	
	
  return IRQ_HANDLED;
}


static void free_irqs(void)
{
	int i;
	for (i = 0; i < COL_NUM; i++) {
		int irq = irq_col_tab[i];
		free_irq(irq, buttons_irq);
	}
}
static void buttons_io_port_init(void)
{
	int i;
	for (i = 0; i < ROW_NUM; i ++) {
		unsigned gpio = gpio_row_tab[i];
		s3c2410_gpio_cfgpin(gpio, gpio_row_out_tab[i]);
		s3c2410_gpio_pullup(gpio,1);
		s3c2410_gpio_setpin(gpio,0);
	}
}

static int buttons4x4_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
{
	     //static int key;
	     //int repeat = key == key_value;
	    // key == key_value;

        if (!ready)
                return -EAGAIN;
        if (count != sizeof key_value)
                return -EINVAL;
	     // if (repeat) {
		     //  return -EAGAIN;
	      //  }

        copy_to_user(buffer, &key_value, sizeof key_value);
	      last_value = key_value;
        ready = 0;
        return sizeof key_value;
}

static unsigned int buttons4x4_select(
        struct file *file,
        struct poll_table_struct *wait)
{
        if (ready)
                return 1;
        poll_wait(file, &buttons_wait, wait);
        return 0;
}

static int buttons4x4_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
{
	switch(cmd) {
	default:
		return -EINVAL;
	}
}
static int buttons4x4_open(struct inode *inode, struct file *file)
{
	int i,ret;
	//int port_irq;
	for (i = 0; i < COL_NUM; i++) {
		int irq = irq_col_tab[i];
		set_irq_type(irq,IRQT_LOW);
		s3c2410_gpio_pullup(gpio_col_tab[i],1);
	  ret = request_irq(irq, buttons_irq, SA_INTERRUPT, DEVICE_NAME, NULL);
	  
		if (ret) {
			unregister_chrdev(BUTTON_MAJOR, DEVICE_NAME);
			printk(DEVICE_NAME " can't request irq %d\n", irq);
			return ret;
	     } 
    }

  printk("keybutton interrupt register!\n");
  return 0;
}
static int buttons4x4_release(struct inode *inode, struct file *file)
{
	free_irqs();
	return 0;
}
static struct file_operations buttons4x4_fops = {
	.owner = THIS_MODULE,
	.open  = buttons4x4_open,
	.ioctl = buttons4x4_ioctl,
	.poll  = buttons4x4_select,
	.read  = buttons4x4_read,
	.release = buttons4x4_release,
};


static int __init buttons4x4_init(void)
{
	int ret;
	//int i;

	ready = 0;
	#ifdef  CONFIG_DEVFS_FS
   devfs_mk_cdev(MKDEV(BUTTON_MAJOR,BUTTON_MINOR),S_IFCHR | S_IRUSR | S_IWUSR | S_IRGRP,DEVICE_NAME);
  #endif
	ret = register_chrdev(BUTTON_MAJOR, DEVICE_NAME, &buttons4x4_fops);
	if (ret < 0) {
	  printk(DEVICE_NAME " can't register major number\n");
	  return ret;
	}
	printk(DEVICE_NAME " keybutton register \n");
	buttons_io_port_init();
	gpbase=ioremap_nocache(0x56000000,0x80);
	kbd_status = KBDSTATUS_UP;
	return 0;
}

static void __exit buttons4x4_exit(void)
{
	iounmap(gpbase);
  #ifdef CONFIG_DEVFS_FS
    devfs_remove(DEVICE_NAME);  
  #endif

	unregister_chrdev(BUTTON_MAJOR, DEVICE_NAME);
	printk(DEVICE_NAME " keybutton unregister \n");
}

module_init(buttons4x4_init);
module_exit(buttons4x4_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("guibaijun");
MODULE_DESCRIPTION("s3c2410_kdb_4x4 driver--07-08-07");