frm.c

硬件的cpu是arm920i2c总线和camera之间的连接驱动在嵌入式linux操作系统下编写

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/compatmac.h>
#include <linux/hdreg.h>
#include <linux/vmalloc.h>
#include <linux/fs.h>
#include <linux/module.h>
#include <linux/blkpg.h>
#include <asm/irq.h>
#include <asm/arch/hardware.h>
#include <asm/arch/irqs.h>

extern int sensorFrameCount;

#define TIMER2_IRQ	58

#ifndef U32
typedef unsigned long U32;
#endif

#define MX1_TMR2_VA_VASE	(IO_ADDRESS(0x203000))
#define _reg_TMR_TCTL2     (*((volatile U32 *)(MX1_TMR2_VA_VASE+0x00)))
#define _reg_TMR_TPRER2    (*((volatile U32 *)(MX1_TMR2_VA_VASE+0x04)))
#define _reg_TMR_TCMP2     (*((volatile U32 *)(MX1_TMR2_VA_VASE+0x08)))
#define _reg_TMR_TSTAT2    (*((volatile U32 *)(MX1_TMR2_VA_VASE+0x14)))

static void timer2_intr_handler(int irq, void *dev_id, struct pt_regs *regs)
{
//	static int count=0;
	
	if (_reg_TMR_TSTAT2)
   	_reg_TMR_TSTAT2 = 0;    // clear interrupt	
	printk("Frame rate: %d\n", sensorFrameCount);
	sensorFrameCount = 0;	   	
//	printk("%d\n", count++);
}

int init_module()
{
	if (request_irq(TIMER2_IRQ, timer2_intr_handler, SA_INTERRUPT, "timer2", NULL))
		printk("request_irq for timer2 failed !\n");
	else
		printk("request_irq for timer2 suceed :-)\n");

   _reg_TMR_TPRER2 = 0;    	// divide by 1
   _reg_TMR_TCMP2 = 32768;   	// 1 Hz for 32768 Hz souce
   _reg_TMR_TCTL2 = 0x19;  	// compare intr, 32K source, enable timer

	
	return 0;
}

void cleanup_module()
{
		free_irq(TIMER2_IRQ, NULL);
}