pc104drv_io_int.c

嵌入式处理器

/*
 * pc104drv_io_int.c
 *
 *
 * Author: wbin <[e-mail]>
 * Date  : $Date: 2006/09/11 $ 
 *
 * $Revision: 1.0.0.1 $
 *
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file COPYING in the main directory of this archive
 * for more details.
 */
 
#include <linux/config.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>

//#include <linux/sched.h>
#include <linux/delay.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <asm/hardware.h>
//#include <asm/semaphore.h>
#include <asm/uaccess.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/sizes.h>

#ifdef CONFIG_DEVFS_FS
#include <linux/devfs_fs_kernel.h>
#endif

#include <asm/arch/pxa-regs.h>
#include "../include/pc104.h"

#undef DEBUG
//#define DEBUG
#ifdef DEBUG
#define DPRINTK(fmt, args...) printk("%s: " fmt, __FUNCTION__ , ## args)
#else
#define DPRINTK(x...) (void)(0)
#endif

#define PC104_BASE		(0xf0000000+0x200000)
#define PC104_IRQ_IN1	(3)		//  IO PORT NO.
#define PC104_IO_IN0	(0)

#define PC104_DEVICE		"UP-TECH PC104 IO & INT"
#define PC104II_MINOR			2
#define pc104ii_devfs_path	"pc104/1"
static int pc104iiMajor = 0;


static irqreturn_t pc104ii_interrupt(int , void *, struct pt_regs *);

static int 
pc104ii_open(struct inode *inode, struct file *filp)
{
	DPRINTK( "pc104ii device open!\n");

	return 0;
}

static int 
pc104ii_release(struct inode *inode, struct file *filp)
{
	DPRINTK( "pc104ii device release!\n");
	return 0;
}

//pc104ii ioctl method
static int pc104ii_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg)
{
	switch(cmd){
	default:
		DPRINTK("IO ioctl test\n");
	}

	return 0;	
}

static struct file_operations pxa270_fops = {
	owner:	THIS_MODULE,
	open:	pc104ii_open,
//	read:	pc104ii_read,	
//	write:	pc104ii_write,
	ioctl:	pc104ii_ioctl,
	release:	pc104ii_release,
};

/*set the gpio into the right mode before transmit, added by wbn */
static int 
pc104ii_set_irq(void)
{
	pxa_gpio_mode(PC104_IRQ_IN1|GPIO_IN);		//gpio mode in input
	GRER0 |=1<<PC104_IRQ_IN1;		// 31:16 -> GPIO<15:0>
	set_irq_type(IRQ_GPIO(PC104_IRQ_IN1), IRQT_RISING);  //IRQT_LOW  IRQT_RISING
	return 0;
}

static irqreturn_t pc104ii_interrupt(int irq, void *_dev, struct pt_regs *r)
{
	int iostatus;
	printk(PC104_DEVICE "pc104ii interrupt happened! \n");
	iostatus=read_gpio_bit(PC104_IO_IN0);
	printk(PC104_DEVICE "pc104ii read IO %d \n", iostatus);
	return IRQ_HANDLED;
}

/*
	read_gpio_bit(x)  read gpio status
	set_gpio_bit(x)  set gpio	
	clear_gpio_bit(x)  clear gpio
*/

static int 
pc104ii_set_gpio(void)
{
	pxa_gpio_mode(PC104_IO_IN0|GPIO_IN);		//gpio mode in input
	GRER0 |=1<<PC104_IO_IN0;		// 31:16 -> GPIO<15:0>
	return 0;
}

int __init pc104ii_init(void)
{
	int ret;

	pc104ii_set_irq();
	
	pc104ii_set_gpio();

		
	if (request_irq(IRQ_GPIO(PC104_IRQ_IN1),pc104ii_interrupt,SA_SHIRQ,PC104_DEVICE,pc104ii_interrupt)) 
		return -EAGAIN;
	
	
	ret = register_chrdev(0, PC104_DEVICE, &pxa270_fops);
	if (ret < 0) {
		printk(PC104_DEVICE " can't get major number\n");
		return ret;
	}
	pc104iiMajor=ret;

#ifdef CONFIG_DEVFS_FS
	devfs_mk_cdev(MKDEV(pc104iiMajor, PC104II_MINOR), 
			S_IFCHR|S_IRUSR|S_IWUSR|S_IRGRP, pc104ii_devfs_path);
#endif
	printk (PC104_DEVICE"\tdevice initialized\n");

	return 0;

}

module_init(pc104ii_init);

#ifdef MODULE
void __exit pc104ii_exit(void)
{

	free_irq(IRQ_GPIO(PC104_IRQ_IN1), pc104ii_interrupt);
#ifdef CONFIG_DEVFS_FS	
	devfs_remove(pc104ii_devfs_path);
#endif	
	unregister_chrdev(pc104iiMajor, PC104_DEVICE);
}
#endif

module_exit(pc104ii_exit);


MODULE_LICENSE("GPL");
MODULE_AUTHOR("wbin<[e-mail]>");
MODULE_DESCRIPTION("Extend PC104 board driver for PXA270");