iic_xf-s4240.c

自己为XF-S4240语音合成芯片所写的驱动程序

/*
		IIC_XF-S4240.c
	 xf-s4240 driver made by StevenZ 
		080620
*/
#include<linux/config.h>
#include<linux/init.h>
#include<linux/module.h>
#include<linux/kernel.h>
#include<linux/fs.h>
#include<linux/poll.h> /*copy_from/to_user()*/
#include<asm/hardware.h>
#include "iic_xf.h"

#define DEVICE "IIC_XF_S4240"
#define MAX_BUF 1024
#define XF_S4240_ADDR 0x80 //iic_xf4240 address
#define X_ADDR 0
#define XF_S4240_IICCON (IICCON_ACKEN|IICCON_CLK512|IICCON_INTR|IICCON_CLKPRE(0x3)) 
                                                                  

int major=0;
int minor=0;

int IIC_XF_S4240_open(struct inode *,struct file *);
int IIC_XF_S4240_release(struct inode *,struct file *);
ssize_t IIC_XF_S4240_read(struct file *,char *,size_t,loff_t *);
ssize_t IIC_XF_S4240_write(struct file *,const char *,size_t,loff_t *);
//unsigned int IIC_XF_S4240_poll(struct file*,poll_table *);

static struct file_operations fops={
	owner: 	THIS_MODULE,
	read:	IIC_XF_S4240_read,
	write:	IIC_XF_S4240_write,
	open:	IIC_XF_S4240_open,
	release:	IIC_XF_S4240_release,
	//poll:	IIC_XF_S4240_poll,
};

#ifdef CONFIG_DEVFS_FS
static devfs_handle_t devfs_xf_s4240_reg;
#endif

struct IIC_XF_S4240_dev
{
	char buffer[MAX_BUF];
	//int size;
	//int index;
};
struct IIC_XF_S4240_dev my_dev;

static int __init IIC_XF_S4240_init(void)
{
	int ret;
	int oldiiccon;
	
	//初始化IIC
	IIC_init();
	Set_IIC_mode(XF_S4240_IICCON, &oldiiccon);
	ret=IIC_Read(XF_S4240_ADDR, X_ADDR);
	//restore IICCON
	Set_IIC_mode(oldiiccon, NULL);
	printk(KERN_DEBUG"XF_S4240 system ack 0x%x\n", ret); //会传0x4a表示初始化正确(复位后)

	//注册设备
	ret=register_chrdev(major,DEVICE,&fops);
	if(ret<0)
	{
	  printk(KERN_DEBUG"register major number failed!\n");
	  return ret;
	}
	else major=ret;
	printk(KERN_DEBUG"register major number %d ok!\n",major);
	
	#ifdef CONFIG_DEVFS_FS
	devfs_xf_s4240_reg=devfs_register(NULL,"xf-s4240",DEVFS_FL_DEFAULT,
				major,minor,S_IFCHR|S_IRUSR|S_IWUSR,&fops,NULL);
	#endif
	//初始化设备变量
	//my_dev.size=0;
	//my_dev.index=0;
	
	printk(KERN_DEBUG DEVICE "initialized\n");
	return 0;//成功初始化回0
}

static void __exit IIC_XF_S4240_exit(void)
{
	#ifdef CONFIG_DEVFS_FS
	devfs_unregister(devfs_xf_s4240_reg);
	#endif
	unregister_chrdev(major,DEVICE);
	printk(KERN_DEBUG"unregister device ok!\n");
}


int IIC_XF_S4240_open(struct inode *inode,struct file *file)
{
	MOD_INC_USE_COUNT;
	printk(KERN_DEBUG DEVICE " opened!\n");
	return 0;	
}

int IIC_XF_S4240_release(struct inode *inode,struct file *file)
{
	MOD_DEC_USE_COUNT;
	printk(KERN_DEBUG DEVICE "closed!\n");	
	return 0;
}

ssize_t IIC_XF_S4240_write(struct file *file,const char *buf,size_t count,loff_t *f_pos)
{ 
	int oldiiccon;
	printk(KERN_DEBUG"begin to write !\n"); 
	if(count>MAX_BUF)
		count=MAX_BUF; 

	if(copy_from_user(my_dev.buffer,buf,count))
		return -EFAULT;
	Set_IIC_mode(XF_S4240_IICCON, &oldiiccon);
	IIC_WriteSerial(XF_S4240_ADDR,X_ADDR,my_dev.buffer,count);
	Set_IIC_mode(oldiiccon, NULL);
	
	return count;
}

ssize_t IIC_XF_S4240_read(struct file *file,char *buf,size_t count,loff_t *f_pos)
{
	
	
	int oldiiccon;
	printk(KERN_DEBUG"begin to read !\n");
	Set_IIC_mode(XF_S4240_IICCON, &oldiiccon);
	IIC_ReadSerial(XF_S4240_ADDR,X_ADDR,my_dev.buffer,count);
	Set_IIC_mode(oldiiccon, NULL);
	
	if(copy_to_user(buf,my_dev.buffer,count))
		return -EFAULT;
	return sizeof(my_dev.buffer);
}

module_init(IIC_XF_S4240_init);
module_exit(IIC_XF_S4240_exit);

MODULE_LICENSE("GPL");