video_buffer.c

一个嵌入式camera驱动 驱动 驱动

/*
 *  drivers/char/arca/video_buffer.c
 *  Driver for control Video buffer and get the Finger data.
 *
 *  Copyright (C) 2003 LingFang Micro System. 
 *
 *  
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version. See
 * the file "COPYING" in the main directory of this archive
 * for more details.
 *
 */

#include <linux/config.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/fs.h>
#include <linux/slab.h>
#include <linux/list.h>
#include <linux/arca-chars.h>

#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/io.h>
#include <asm/delay.h>
#include <asm/hardware.h>

//SCCB define.

#define SCC_PORT_MASK  0x3F
#define SCC_DATA_HIGH  0x80 + SCC_PORT_MASK	//PA7 -- data
#define SCC_DATA_LOW   0x00 + SCC_PORT_MASK
#define SCC_CLK_HIGH   0x40		//PA6 -- clock
#define SCC_CLK_LOW    0x00
/*
#define SCC_PORT_MASK  0xCF
#define SCC_DATA_HIGH  0x20 + SCC_PORT_MASK	//PA5 -- data
#define SCC_DATA_LOW   0x00 + SCC_PORT_MASK
#define SCC_CLK_HIGH   0x10		//PA4 -- clock
#define SCC_CLK_LOW    0x00
*/
#define SCC_PORT       *(unsigned char volatile *)(0xE0000504)
//SCCB define end.	
//The driver's function define
#define FIFO_RESET_DELAY 0x20
//Windows defines.
#define X_START 176
#define Y_START 132
#define X_WIDTH 296
#define Y_WIDTH 300
//Windows define end.
static int	video_buffer_open(struct inode *, struct file *);
static int	video_buffer_close(struct inode *, struct file *);
static ssize_t	video_buffer_read(struct file *, char *, unsigned long , loff_t *);
static ssize_t	video_buffer_write(struct file *, const char *, size_t, loff_t *);
static int	video_buffer_ioctl(struct inode *, struct file *,
			     unsigned int, unsigned long);
static void     video_buffer_interrupt(int irq, void *dev_id, struct pt_regs *regs);
//This is the address for my video buffer.
static unsigned long VIDEO_BUFFER_ADDRESS;
//This device's struct.
struct video_buffer_dev_struct {
	int opened;
	char *name;
	void *private;
} video_buffer_dev;

video_buffer_dev_minor = 0x22; //Here are the same number in the /dev/arca/video_buffer nods.

/***************************************************************************
 **  define driver struct.  
 ** 
 ***************************************************************************/

static struct file_operations video_buffer_fops =
{
	open:	video_buffer_open,
	release:video_buffer_close,
	read:	video_buffer_read,
	write:	video_buffer_write,
	ioctl:	video_buffer_ioctl,
};
//SCCB function define.
void sccb_write_ov_sio_data_io(unsigned char devaddress, unsigned char regaddress, unsigned char mydata);
void sccb_delay(void)
{
	unsigned long i;
	for(i=0x0000;i<0xF000;i++)
    {
		i++;
	}
}
/////////////////////////////////////////////////////////////////////////////////////////////////////
/***************************************************************************
 **  driver open process.
 ** 
 ***************************************************************************/
void reset_7620(void)
{
	unsigned long i;
	unsigned char data;
	//__gpiod_write(0xDF);
	//__gpiod_as_outputs();	
	*(unsigned char *)(0xE0000534) = 0xD0;
	*(unsigned long *)(0xE0000530) = 0x00000FF0;

	*(unsigned char *)(0xE0000534) = 0x10;

	for(i=0;i<FIFO_RESET_DELAY;i++)
	{i++;}
	
	data = *(unsigned char volatile *)(VIDEO_BUFFER_ADDRESS);
	data = *(unsigned char volatile *)(VIDEO_BUFFER_ADDRESS + 1);

	for(i=0;i<FIFO_RESET_DELAY;i++)
	{i++;}

	*(unsigned char *)(0xE0000534) = 0xD0;	
}
static int video_buffer_open(struct inode *inode, struct file *filp)
{
	unsigned long i;
	unsigned char data;
	unsigned long reg;
	unsigned char hstart,hend,vstart,vend;
	
	if (video_buffer_dev.opened) {
		printk(KERN_INFO "video_buffer: the device is busy\n");
		return -EBUSY;
	}
	VIDEO_BUFFER_ADDRESS = ioremap(0x84000000,0x4B000);
	*(unsigned char *)(0xE0000534) = 0xD0;
	*(unsigned long *)(0xE0000530) = 0x00000FF0;

	//*(unsigned long volatile *)(0xE1020008) = 0x02222200;		
        *(unsigned long volatile *)(0xE1020008) = 0x04444400;		
	__gpioa_write(0xFF);
	__gpioa_as_outputs();	
	
	hstart = 0x2F + (X_START/4);
	hend = hstart + (X_WIDTH/4);
	vstart = 0x06 + (Y_START/2);
	vend = vstart - 1 + (Y_WIDTH/2);
	
	
	sccb_write_ov_sio_data_io(0x42,0x28,0x20);
	sccb_delay();
	//sccb_write_ov_sio_data_io(0x42,0x17,0x57);
	sccb_write_ov_sio_data_io(0x42,0x17,hstart);
	sccb_delay();
	//sccb_write_ov_sio_data_io(0x42,0x18,0xA7);
	sccb_write_ov_sio_data_io(0x42,0x18,hend);
	sccb_delay();
	//sccb_write_ov_sio_data_io(0x42,0x19,0x2E);
	sccb_write_ov_sio_data_io(0x42,0x19,vstart);
	sccb_delay();
	//sccb_write_ov_sio_data_io(0x42,0x1A,0xCD);
	sccb_write_ov_sio_data_io(0x42,0x1A,vend);
        sccb_delay();
        /*
	for(i=0;i<0x1000000;i++)
	{i++;}
	__gpiod_write(0x10);

	for(i=0;i<0x100000;i++)
	{i++;}
	
	data = *(unsigned char volatile *)(VIDEO_BUFFER_ADDRESS);
	data = *(unsigned char volatile *)(VIDEO_BUFFER_ADDRESS + 1);

	for(i=0;i<0x1000000;i++)
	{i++;}

	__gpiod_write(0xDF);
        */
        reset_7620();
	MOD_INC_USE_COUNT;
	video_buffer_dev.opened = 1;

	
	//printk("The ioremap result for fucking video buffer is %08X.\n",VIDEO_BUFFER_ADDRESS);

	return 0;
}


/***************************************************************************
 ** driver close process.
 ** 
 ***************************************************************************/

static int video_buffer_close(struct inode *inode, struct file *filp)
{
	MOD_DEC_USE_COUNT;
	video_buffer_dev.opened = 0;
	return 0;
}



/***************************************************************************
 **  Read video buffer data.
 ** 
 ***************************************************************************/

static ssize_t video_buffer_read(struct file *filp, char *buf,
			   unsigned long count, loff_t *ppos)
{
	unsigned char mydata;
	unsigned long i;
	reset_7620();
	//for(i=0;i<(640*480);i++)
	//for(i=0;i<(320*320);i++)
	for(i=0;i<(X_WIDTH * Y_WIDTH);i++)
	{
		buf[i] = *(unsigned char volatile *)(VIDEO_BUFFER_ADDRESS + i);	
	}
	return 0x01;

}


/***************************************************************************
 ** Dummy Write data. 
 ** 
 ***************************************************************************/
static ssize_t video_buffer_write(struct file *filp, const char *buf,
			    size_t count, loff_t *ppos)
{
	return 0;
}


/***************************************************************************
 **  ioctl function. 
 ** 
 ***************************************************************************/

static int video_buffer_ioctl(struct inode *inode, struct file *filp,
			unsigned int cmd, unsigned long arg)
{
	int val=0;
	unsigned long value=0;
	unsigned long flags;

	switch (cmd) {
	case 0:
		return 0x00;
	case 1:
		return 0x01;

	}

	return -EINVAL;
}


/***************************************************************************
 ** interrupt process routine. 
 ** 
 ***************************************************************************/

static void video_buffer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{

}

/***************************************************************************
 **  Init routine
 ** 
 ***************************************************************************/

static int __init video_buffer_init(void)
{
	int result;
	int i;
	unsigned long value=0;

	
	result = arca_register_chrdev(video_buffer_dev_minor, "video_bffer",
				      &video_buffer_fops);

	return result;
}



/***************************************************************************
 **  exit routine.
 ** 
 ***************************************************************************/
static void __exit video_buffer_exit(void)
{
	printk(KERN_INFO "video_buffer driver exit.\n");
}

//This is the SCCB function.
//The devaddress is the address of OV7620 sensor, it should be 0x42,and decided by the power on pull up/down set.
//The regaddress is the address of OV register,
//The data is the data you want to change to .
void sccb_write_ov_sio_data_io(unsigned char devaddress, unsigned char regaddress, unsigned char mydata)
{
	unsigned char i,j,k;
	unsigned char data;
	
	
	SCC_PORT = SCC_DATA_HIGH + SCC_CLK_HIGH; //Set data and clock high for start.
	//data = *(unsigned char volatile *)(0xE0000504);
	//printk("PORTA is %02X.\n",data);
	SCC_PORT = SCC_DATA_LOW + SCC_CLK_HIGH; //Set data low for start signal of IIC.
	//data = *(unsigned char volatile *)(0xE0000504);
	//printk("PORTA is %02X.\n",data);	
	sccb_delay();

	//send device id address.
	j = 0x80;
	for(i=0;i<0x08;i++)
	{
		k = j & devaddress;
		if(j == k)
		{		//Send data high when this bit is "1".

				sccb_delay();
				SCC_PORT = SCC_DATA_HIGH + SCC_CLK_LOW;

				sccb_delay();
				SCC_PORT = SCC_DATA_HIGH + SCC_CLK_HIGH;
				
				sccb_delay();
				SCC_PORT = SCC_DATA_HIGH + SCC_CLK_LOW;

		}
		else
		{		//Send data low when this bit is "0".

				sccb_delay();
				SCC_PORT = SCC_DATA_LOW + SCC_CLK_LOW;

				sccb_delay();
				SCC_PORT = SCC_DATA_LOW + SCC_CLK_HIGH;

				sccb_delay();
				SCC_PORT = SCC_DATA_LOW + SCC_CLK_LOW;

		}
		j = j>>1;
	}
	//send x bit.

	sccb_delay();
	SCC_PORT = SCC_DATA_HIGH + SCC_CLK_LOW;

	sccb_delay();
	SCC_PORT = SCC_DATA_HIGH + SCC_CLK_HIGH;

	sccb_delay();
	SCC_PORT = SCC_DATA_HIGH + SCC_CLK_LOW;

	//send register address.
	j = 0x80;
	for(i=0;i<0x08;i++)
	{
		k = j & regaddress;
		if(j == k)
		{		//Send data high when this bit is "1".

				sccb_delay();
				SCC_PORT = SCC_DATA_HIGH + SCC_CLK_LOW;

				sccb_delay();
				SCC_PORT = SCC_DATA_HIGH + SCC_CLK_HIGH;
				
				sccb_delay();
				SCC_PORT = SCC_DATA_HIGH + SCC_CLK_LOW;

		}
		else
		{		//Send data low when this bit is "0".

				sccb_delay();
				SCC_PORT = SCC_DATA_LOW + SCC_CLK_LOW;

				sccb_delay();
				SCC_PORT = SCC_DATA_LOW + SCC_CLK_HIGH;

				sccb_delay();
				SCC_PORT = SCC_DATA_LOW + SCC_CLK_LOW;

		}
		j = j>>1;
	}
	//send x bit.
	//*(unsigned char *)(0x60000000) = 0b10000000;
	sccb_delay();
	SCC_PORT = SCC_DATA_HIGH + SCC_CLK_LOW;

	sccb_delay();
	SCC_PORT = SCC_DATA_HIGH + SCC_CLK_HIGH;

	sccb_delay();
	SCC_PORT = SCC_DATA_HIGH + SCC_CLK_LOW;

	//send data.
	j = 0x80;
	for(i=0;i<0x08;i++)
	{
		k = j & mydata;
		if(j == k)
		{		//Send data high when this bit is "1".

				sccb_delay();
				SCC_PORT = SCC_DATA_HIGH + SCC_CLK_LOW;

				sccb_delay();
				SCC_PORT = SCC_DATA_HIGH + SCC_CLK_HIGH;
				
				sccb_delay();
				SCC_PORT = SCC_DATA_HIGH + SCC_CLK_LOW;

		}
		else
		{		//Send data low when this bit is "0".

				sccb_delay();
				SCC_PORT = SCC_DATA_LOW + SCC_CLK_LOW;
	
				sccb_delay();
				SCC_PORT = SCC_DATA_LOW + SCC_CLK_HIGH;

				sccb_delay();
				SCC_PORT = SCC_DATA_LOW + SCC_CLK_LOW;

		}
		j = j>>1;
	}

	//send x bit.

	sccb_delay();
	SCC_PORT = SCC_DATA_HIGH + SCC_CLK_LOW;

	sccb_delay();
	SCC_PORT = SCC_DATA_HIGH + SCC_CLK_HIGH;

	sccb_delay();
	SCC_PORT = SCC_DATA_HIGH + SCC_CLK_LOW;

	sccb_delay();

	sccb_delay();
	SCC_PORT = SCC_DATA_LOW + SCC_CLK_HIGH;

	sccb_delay();
	SCC_PORT = SCC_DATA_HIGH + SCC_CLK_HIGH;
}

MODULE_AUTHOR ("");
MODULE_DESCRIPTION ("video_buffer driver");
MODULE_LICENSE("GPL");



module_init(video_buffer_init);
module_exit(video_buffer_exit);