tw2835.c

tw2835在智原平台的驱动 内核用的是2.6的内核

#include <linux/module.h>
#include <linux/config.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/spinlock.h>
#include <linux/proc_fs.h>
#include <asm/uaccess.h>
#include <linux/miscdevice.h>
#include "tw2835.h"

MODULE_AUTHOR("GM Corp.");
MODULE_LICENSE("GM License");

#define IPMODULE MULTI
#define IPNAME   TW2835

DECLARE_MUTEX(bus_lock);

static int tw2835_open(struct inode *inode, struct file *file)
{
	return 0;
}

static int tw2835_release(struct inode *inode, struct file *file)
{
	return 0;
}

void tw2835_data_write(u8 chip, u8 bank, u8 reg, int num, unsigned char *buf)
{
	int i;
	u8 dev = 0;
	volatile u8 *base;

	if(dev >= IP_COUNT)
		return;

	base = (u8*)IP_va_base[dev];

	down(&bus_lock);

	switch (chip)
	{
	  case 0:
		*(base) = 0xFC | bank;
	    	break;
	  case 1:
		*(base) = 0xF3 | (bank << 2);
	    	break;
	  case 2:
		*(base) = 0xCF | (bank << 4);
	    	break;
	  case 3:
		*(base) = 0x3F | (bank << 6);	 
	    	break;		 
	  default:
		break;
	}

	*(base+0x400) = reg;
    	for(i = 0; i < num; i++, buf++)
    		*(base + 0x800) = *buf;
	up(&bus_lock);
    	
}EXPORT_SYMBOL(tw2835_data_write);

void tw2835_data_read(u8 chip, u8 bank, u8 reg, int num, unsigned char *buf)
{
	int i;
	u8 dev = 0;
	volatile u8 *base;

	if(dev >= IP_COUNT)
		return;

	base = (u8*)IP_va_base[dev];

	down(&bus_lock);

	switch (chip)
	{
	  case 0:
		*(base) = 0xFC | bank;
	    	break;
	  case 1:
		*(base) = 0xF3 | (bank << 2);
	    	break;
	  case 2:
		*(base) = 0xCF | (bank << 4);
	    	break;
	  case 3:
		*(base) = 0x3F | (bank << 6);	  
	    	break;		
	  default:
		break;
	}
	
	*(base+0x400) = reg;
    	for(i = 0; i < num; i++, buf++)
    		*buf = *(base + 0xC00);
	up(&bus_lock);
}EXPORT_SYMBOL(tw2835_data_read);


static int tw2835_ioctl(struct inode *inode, struct file *file,
		     unsigned int cmd, unsigned long arg)
{
	tw2835_params gm;
	
	switch (cmd) {
	case tw2835_ioctl_write:
		if (copy_from_user (&gm, (struct tw2835_params*)arg, sizeof(tw2835_params)))
			return -EFAULT;
		
		tw2835_data_write(gm.chip,gm.bank,gm.reg,gm.num,gm.buf);
		return 0;
	case tw2835_ioctl_read:
		if (copy_from_user (&gm, (struct tw2835_params*)arg, sizeof(tw2835_params)))
			return -EFAULT;

		tw2835_data_read(gm.chip,gm.bank,gm.reg,gm.num,gm.buf);
		return 0;
	default:
		printk("GPIO ioctl function error\n");
		return -EINVAL;
	}
}


static const struct file_operations tw2835_fops = {
	.owner=THIS_MODULE,
	.ioctl=tw2835_ioctl,
	.open=tw2835_open,
};

static struct miscdevice tw2835_miscdev = {
	.minor = MISC_DYNAMIC_MINOR,
	.name = "tw2835",
	.fops = &tw2835_fops,
};

static int __init tw2835_init(void)
{
    int ret;
    unsigned char buf_1[10]={0xa0,0xa1,0xa2,0xa3,0xa4,0xa5,0xa6,0xa7,0xa8,0xa9}, buf_2[10];
    int i;

    ret = misc_register(&tw2835_miscdev);
    if (ret < 0) {
	printk(KERN_ERR "tlclk: misc_register returns %d.\n", ret);
    	return ret;
    }
#if 0    //for debug
    tw2835_data_write(0, 0x2, 0x20, 10, buf_1);
    tw2835_data_read(0, 0x2, 0x20, 10, buf_2);
    
    for(i = 0; i < 10; i++)
    	if(buf_1[i] != buf_2[i])
    		printk("Compare data fail, read data = 0x%x, correct data = 0x%x\n",buf_2[i],buf_1[i]);  	
    printk("Test finished\n");
#endif        
    return 0;
}

static void __exit tw2835_exit(void)
{
    misc_deregister (&tw2835_miscdev);
}

module_init(tw2835_init);
module_exit(tw2835_exit);