ad_driver.c

基于ＬＩＮＵＸ嵌入式系统

#if 0
#endif

typedef unsigned long long u_quad_t;
#include <linux/config.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/miscdevice.h>
#include <linux/sched.h>
#include <linux/delay.h>
#include <linux/poll.h>
#include <linux/spinlock.h>
#include <linux/irq.h>
#include <linux/delay.h>

//#include <asm/hardware.h>

#include "LPC2294.h"

#define MYMAJOR 240
#define Fosc    11059200 
#define Fcclk   (Fosc * 4)                  // be equal or less  than 60MHz. 
#define Fcco    (Fcclk * 4)                 //CCO frequence,should be 2¡¢4¡¢8¡¢16 multiples  
#define Fpclk   (Fcclk / 4) * 1 

unsigned int adc_data;
char 	str_buf[32];

int init_module(void)
{
	adc_init();

	return 0;
}

void cleanup_module(void)
{
	unregister_chrdev(MYMAJOR, "adc_devices");

	printk(" unregister_chrdev is OK \n");
}

int adc_open(struct inode *inode, struct file *file)
{
	PINSEL1 = 0x01400000;

	ADCR = 	(1 << 0)			|	//SEL= 1;
			((Fpclk / 1000000 -1) << 6)	|	//CLKDIV = Fpclk/ 1000 000 -1
			(0 << 16)			|	//BURST = 0;
			(0 << 17)			|	//CLKS = 0;
			(1 << 21)			|	//FDN =1;
			(0 << 22)			|	//TEST1 : 0 = 00
			(1 << 24)			|	//START = 1;
			(0 << 27);				//EDGE = 0;
	
	mdelay(10);
	adc_data = ADDR;
}

int adc_read(struct file *filp, char *rev_buf, size_t len, loff_t *adc_pos)
{
	ADCR = (ADCR & 0x00FFFF00) | 0x01 | (1 << 24);
	while((ADDR & 0x80000000) == 0);
	ADCR = ADCR | (1 << 24);
	while((ADDR & 0x80000000) == 0);
	adc_data = ADDR;
	adc_data = (adc_data >> 6) & 0x3FF;

	//sprintf(str_buf, "% 4dmv at VIN1", adc_data);
	copy_to_user(rev_buf, (char *)&adc_data, sizeof(adc_data));	
	mdelay(10);

	return sizeof(adc_data);
}

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

static struct file_operations adc_fops = {
	owner:		THIS_MODULE,
	open:		adc_open,
	read:		adc_read,
	release:	adc_release,
};

int adc_init(void)
{
	int ret;
	
	ret = register_chrdev(MYMAJOR, "adc_devices", &adc_fops);
	if (ret == 0) {
		printk(" register_chrdev is OK \n");
	}

	return ret;
}