gpio_do.c

这是一个PXA－XCLALE嵌入式开发系统下开发的一个GPIO驱动程序。适合LINUX-2.6.12内核。

//***********************************************
#include <linux/fs.h>
#include <linux/unistd.h>
#include <linux/ioctl.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/fcntl.h>
#include <asm/uaccess.h>
#include <asm-arm/arch-pxa/pxa-regs.h>
#include <asm-arm/arch-pxa/xmu255.h>
#include <asm-arm/arch-pxa/hardware.h>
#define GPIO_MAJOR 253
#define GPIO_NAME "GPIO"
#define GPIO_VERSION "VERSION0.1"
#define cmd_1 0x1
#define cmd_2 0x2
#define cmd_3 0x3
static int gpio_open(struct inode *,struct file *);
static int gpio_release(struct inode *,struct file *);
static int gpio_ioctl(struct inode *,struct file *,unsigned int,unsigned long);
//***********************************************
static struct file_operations gpio_fops=
{
	.open =	gpio_open,
	.release = gpio_release,
	.ioctl = gpio_ioctl,
};
static struct gpio_set_struct
{
	unsigned long W_GPDR0;
	unsigned long W_GPDR1;
	unsigned long W_GPDR2;
	unsigned long W_GPSR0;
	unsigned long W_GPSR1;
	unsigned long W_GPSR2;
	unsigned long W_GPCR0;
	unsigned long W_GPCR1;
	unsigned long W_GPCR2;
	unsigned long W_GPLR0;
	unsigned long W_GPLR1;
	unsigned long W_GPLR2;
	unsigned long W_GRER0;
	unsigned long W_GRER1;
	unsigned long W_GRER2;
	unsigned long W_GFER0;
	unsigned long W_GFER1;
	unsigned long W_GFER2;
	unsigned long W_GEDR0;
	unsigned long W_GEDR1;
	unsigned long W_GEDR2;
	unsigned long W_GAFR0_L;
	unsigned long W_GAFR1_L;
	unsigned long W_GAFR2_L;
   	unsigned long W_GAFR0_U;
    	unsigned long W_GAFR1_U;
    	unsigned long W_GAFR2_U;

}gpio_set1;
//*****************************************************************************
int __init gpio_init(void)
{
        register_chrdev(GPIO_MAJOR,GPIO_NAME,&gpio_fops);
        printk("%s %s initialized.\n",GPIO_NAME,GPIO_VERSION);
        return 0;
}
module_init(gpio_init);
void __exit gpio_exit(void)
{
        unregister_chrdev(GPIO_MAJOR,GPIO_NAME);
        printk("%s unregisted.\n",GPIO_NAME);
}
module_exit(gpio_exit);
//********************************************************************************

static int gpio_open(struct inode *inode,struct file *file)
{
	try_module_get(THIS_MODULE);
	return 0;
}
//*********************************************************************************

static int gpio_release(struct inode *inode,struct file *file)
{
	module_put(THIS_MODULE);
	return 0;
}
//**********************************************************************************

static int gpio_ioctl(struct inode *inode,struct file *file,unsigned int cmd,unsigned long arg)
{
	//static struct gpio_set_struct gpio_set1;
	copy_from_user(&gpio_set1,(void *)arg,sizeof(gpio_set1));
	printk("now go int the ioctl\n");
	switch(cmd)
	{
		case cmd_1:
			gpio_set1.W_GPLR0=GPLR0;
			gpio_set1.W_GPLR1=GPLR1;
			gpio_set1.W_GPLR2=GPLR2;
			gpio_set1.W_GPDR0=GEDR0;
			gpio_set1.W_GPDR1=GEDR1;
			gpio_set1.W_GPDR2=GEDR2;
			gpio_set1.W_GAFR0_L=GAFR0_L;
			gpio_set1.W_GAFR1_L=GAFR1_L;
			gpio_set1.W_GAFR2_L=GAFR2_L;
			gpio_set1.W_GAFR0_U=GAFR0_U;
			gpio_set1.W_GAFR1_U=GAFR1_U;
			gpio_set1.W_GAFR2_U=GAFR2_U;
			copy_to_user((void *)arg,&gpio_set1,sizeof(gpio_set1));
			printk("now go in the cmd1\n");
			return 0;	
		case cmd_2:
			GPSR0=GPSR0|gpio_set1.W_GPSR0;
			GPSR1=GPSR1|gpio_set1.W_GPSR1;
			GPSR2=GPSR2|gpio_set1.W_GPSR2;
			
			GPCR0=GPCR0|gpio_set1.W_GPCR0;
			GPCR1=GPCR1|gpio_set1.W_GPCR1;
			GPCR2=GPCR2|gpio_set1.W_GPCR2;
			
			GPDR0=GPDR0|gpio_set1.W_GPDR0;
			GPDR1=GPDR1|gpio_set1.W_GPDR1;
			GPDR2=GPDR2|gpio_set1.W_GPDR2;	

			GRER0=GRER0|gpio_set1.W_GRER0;
			GRER1=GRER1|gpio_set1.W_GRER1;
			GRER2=GRER2|gpio_set1.W_GRER2;
			
			GFER0=GFER0|gpio_set1.W_GFER0;
			GFER1=GFER1|gpio_set1.W_GFER1;
			GFER2=GFER2|gpio_set1.W_GFER2;	
			
			GAFR0_L=GAFR0_L|gpio_set1.W_GAFR0_L;
			GAFR1_L=GAFR1_L|gpio_set1.W_GAFR1_L;
			GAFR2_L=GAFR2_L|gpio_set1.W_GAFR2_L;
			
			GAFR0_U=GAFR0_U|gpio_set1.W_GAFR0_U;
			GAFR1_U=GAFR1_U|gpio_set1.W_GAFR1_U;
			GAFR2_U=GAFR2_U|gpio_set1.W_GAFR2_U;
			printk("now go in the cmd2\n");
			printk("now the value of GPLR1 is %x\n",GPLR1);
			printk("now the value of GAFR1_L is %x\n",GAFR1_L);
			return 1;
		case cmd_3:
			GPLR0=GPLR0&gpio_set1.W_GPLR0;
			GPLR1=GPLR1&gpio_set1.W_GPLR1;
			GPLR2=GPLR2&gpio_set1.W_GPLR2;
			printk("now go in the cmd3\n");
			return 2;
		default:
			printk("please input the value of cmd\n");
			return 3;
	}
}