touch.c

这个是针对pxa270s写的触摸屏的使用函数

/***************************************************
  Copyright(C), 2009 , JUST
  File name: touch.h
  Author: 郑慎    Version: 0.1    Date: 09/03/29
  Description: 实现触摸屏的打开和取点等功能
  History:
	09/03/29 V0.1
***************************************************/

#include <stdio.h>
#include <stdlib.h>
#include <linux/fb.h>
#include <asm/fcntl.h>
#include <linux/input.h>
#include <asm/mman.h>
#include "touch.h"

#define MAX_DRAG_X 80//区别划动的x方向最大值
#define MAX_DRAG_Y 80//区别划动的y方向最大值

/*双击间隔时间0.5s*/ 
#define WAIT_TIME_NSEC 500000 

int touchscreen_fd = 0;	/* touch screen device handle */				

/*时间的拷贝*/
void copy_time(struct timeval *t1,struct timeval *t2)
{
	t1->tv_sec=t2->tv_sec;
	t1->tv_usec=t2->tv_usec;
} 

/*点的拷贝*/
void copy_point(POINT *p1,POINT *p2)
{
	p1->x=p2->x;
	p1->y=p2->y;
}

// Retrieve an average data from touch screen input device
int cal_data_avg(int ts_handler, ts_event_t * ts_avg, unsigned short max_num)
{
	ts_event_t *tmpDataArr;
	//ts_event_t tmpData;
	unsigned short bp, i ;
	unsigned short count;
	long tempX, tempY;
	int ret,tFlg=0,timeFlg=1;
   	
	static int pressureFlg=1;
	static int curr_x = 0, curr_y = 0, curr_p = 0;
  	struct input_event ev;


	//Allocate a buffer for input data
	
	tmpDataArr = (ts_event_t *)malloc(max_num * sizeof(ts_event_t));
	if (tmpDataArr == NULL)
	{
		printf("Error: malloc failed.\n");
		return -1;
	}

	//printf("malloc ok.\n");
	for (i = 0; i < max_num; i++)
	{
		tmpDataArr[i].x = 0;
		tmpDataArr[i].y = 0;
		tmpDataArr[i].pressure = 0;
		tmpDataArr[i].time.tv_sec=0;
		tmpDataArr[i].time.tv_usec=0;
	}

	// Read a set of data into buffer
	count = 0;
	do
	{
		bp = 0;
		while (1)
		{
			memset(&tmpDataArr[bp], 0, sizeof(ts_event_t));
	    		ret = read(ts_handler, &ev, sizeof(struct input_event));
	 
	  		if (ret < sizeof(struct input_event))
			{
				//printf("ret<size!!!\n"); 
				break;
			}
	    		//printf("ev.time.tv_sec=%d,",ev.time.tv_sec);
		   	//printf("ev.time.tv_usec=%d,",ev.time.tv_usec);	
		    	//printf("ev.type=0x%x,",ev.type);
		    	//printf("ev.code=0x%x,",ev.code);
		    	//printf("ev.value=%d!\n",ev.value);
	    		
			if(timeFlg)
			{
				ts_avg->time.tv_sec=ev.time.tv_sec;
				ts_avg->time.tv_usec=ev.time.tv_usec;
				timeFlg=0;
			}
	    		if (ev.type == EV_ABS) switch (ev.code) {
			case ABS_X:
				curr_x = ev.value;
				break;
			case ABS_Y:
		  		curr_y = ev.value;
				break;
			case ABS_PRESSURE:
				curr_p = ev.value;
				break;
			}

			/* We consider having a complete ts event */
			
			tmpDataArr[bp].x = curr_x;
			tmpDataArr[bp].y = curr_y;
			tmpDataArr[bp].pressure = curr_p;
			if(curr_p!=0)
				tFlg=1;//第一次中未满max_num时
			//printf("tmpDataArr[%d].x=%d,",bp,curr_x);
			//printf("tmpDataArr[%d].y=%d,",bp,curr_y);
			//printf("tmpDataArr[%d].pressure=%d\n",bp,curr_p);
			//printf("pressureFlg=%d\n",pressureFlg);

			if (bp < max_num)
			{
				if((curr_x!=0&&curr_y!=0&&curr_p==0)&&(pressureFlg!=1||tFlg))
				{
					//printf("pressureFlg=%d!!!!\n",pressureFlg);
					//bp++;
					break;
				}
				else
					bp++;
			}
			else
			{
				//printf("break>max_num!!!\n");
				break;
			}

		}
		count = bp;
		//printf("count=%d!!!!\n",count);
	}while (0);

	if(curr_x!=0&&curr_y!=0&&curr_p==0)
		pressureFlg=0;

	tempX =	tempY = 0;

	for (bp=0; bp < count; bp++)
	{
		tempX += tmpDataArr[bp].x;
		if(bp!=0)
		{
			tempY += tmpDataArr[bp].y;
		}
		//if(pressureFlg!=0&&tmpDataArr[bp].x==0)
		//	pressureFlg=1;
	}

	// Calculate an average value
	if(count!=0)
	{
    		ts_avg->x = tempX / count;
		if(count>1)
			ts_avg->y = tempY / (count-1.0);
		else ts_avg->y = curr_y;
	}
	else
	{
		ts_avg->x = curr_x;
		ts_avg->y = curr_y;
	}

	switch(pressureFlg)
	{
	case 0:
		ts_avg->pressure = 0;
		pressureFlg=1;
		break;
	case 1: 
		ts_avg->pressure = 1;
		pressureFlg=2;
		break;
	case 2:
		ts_avg->pressure = 2;
		break;
	}
	// Release
	free(tmpDataArr);
}

/*根据两个点的位置分析操作类型*/
int analize_type(POINT *p1,POINT *p2)
{
	if(p1->y-p2->y>MAX_DRAG_Y)
		return DOWN;
	
	if(p1->y-p2->y<-MAX_DRAG_Y)
		return UP;
	
	if(p1->x-p2->x>MAX_DRAG_X)
		return LEFT;
	
	if(p1->x-p2->x<-MAX_DRAG_X)
		return RIGHT;

	return STAY;
}

/*测试两次单点间隔是否在双点时间内,是返回1,否则返回0*/
int IsSmallTime(struct timeval *t1,struct timeval *t2)
{
	if(t2->tv_sec-t1->tv_sec>=2)
		return 0;
	if(t2->tv_sec-t1->tv_sec==1)
	{
		if(1000000+t2->tv_usec-t1->tv_usec>WAIT_TIME_NSEC)
			return 0;
		return 1;
	}
	if(t2->tv_usec-t1->tv_usec>WAIT_TIME_NSEC)
		return 0;
	return 1;
}

int ts_operation(TS_OP *ret,int support_dc)
{
	ts_event_t  ts_CalPoint;/* touch screen calibration pBuffer */
	char * tsconf_name;
	unsigned short x_max, y_max;
	unsigned short i;
  	FILE * fp;
	
	
	static int firstFlg=1;//一次双点后或第一次点击
	static POINT newp1,newp2,oldp1,oldp2;
	static struct timeval newt1,newt2,oldt1,oldt2;
	
	
	i = 0;
	//初始化开启触摸屏
	touchscreen_fd = open(TOUCHSCREEN_DEV, O_RDONLY);
	if (touchscreen_fd < 0)
	{
		fprintf (stderr, "Cannot open touch screen device [%s].\n", TOUCHSCREEN_DEV);
        	return -1;
    	}
	else
	{
		fprintf (stderr, "the  touch screen device [%s]is opened.\n", TOUCHSCREEN_DEV);
             	fprintf (stderr, "please touch the screen to test the driver is working \n");
	}
	
	//读点直至抬起
	i=0;
	while(1)
	{
		printf("begin cal!\n");
		cal_data_avg(touchscreen_fd, &ts_CalPoint, 6);
		if(ts_CalPoint.pressure==1)
		{
			newp1.x=ts_CalPoint.x;
			newp1.y=ts_CalPoint.y;
			newt1.tv_sec=ts_CalPoint.time.tv_sec;
			newt1.tv_usec=ts_CalPoint.time.tv_usec;
		}
		else	if(ts_CalPoint.pressure==0)
			{
				if(i==0)
				{
					newp1.x=ts_CalPoint.x;
					newp1.y=ts_CalPoint.y;
					newp2.x=ts_CalPoint.x;
					newp2.y=ts_CalPoint.y;
					newt1.tv_sec=ts_CalPoint.time.tv_sec;
					newt1.tv_usec=ts_CalPoint.time.tv_usec;
					newt2.tv_sec=ts_CalPoint.time.tv_sec;
					newt2.tv_usec=ts_CalPoint.time.tv_usec;
					break;
				}
				else
				{
					newp2.x=ts_CalPoint.x;
					newp2.y=ts_CalPoint.y;
					newt2.tv_sec=ts_CalPoint.time.tv_sec;
					newt2.tv_usec=ts_CalPoint.time.tv_usec;
					break;
				}
			}
		i++;
	}
	
	//产生操作类型
	copy_time(&ret->time,&newt1);
	copy_point(&ret->pos_start,&newp1);
	copy_point(&ret->pos_end,&newp2);
	ret->type=TS_RESERVE;

	if(support_dc)
	{/*有双击功能*/
		printf("newt1.tv_sec=%d,tv_usec=%d\n",newt1.tv_sec,newt1.tv_usec);
		printf("oldt2.tv_sec=%d,tv_usec=%d\n",oldt2.tv_sec,oldt2.tv_usec);
		if(firstFlg||!IsSmallTime(&oldt2,&newt1))
		{
			switch(analize_type(&newp1,&newp2))
			{
			case UP:
				ret->type=TS_UP;
				break;
			case DOWN:
				ret->type=TS_DOWN;
				break;
			case LEFT:
				ret->type=TS_LEFT;
				break;
			case RIGHT:
				ret->type=TS_RIGHT;
				break;
			case STAY:
				ret->type=TS_CLICK;
				break;
			}
			copy_time(&oldt1,&newt1);
			copy_time(&oldt2,&newt2);
			firstFlg=0;
		}
		else
		{
			
			ret->type=TS_DCLICK;
			firstFlg=1;
		}
	}
	else
	{/*无双击功能*/
		switch(analize_type(&newp1,&newp2))
		{
		case UP:
			ret->type=TS_UP;
			break;
		case DOWN:
			ret->type=TS_DOWN;
			break;
		case LEFT:
			ret->type=TS_LEFT;
			break;
		case RIGHT:
			ret->type=TS_RIGHT;
			break;
		case STAY:
			ret->type=TS_CLICK;
			break;
		}
		firstFlg=1;
	}	

	//关闭触摸屏
	close(touchscreen_fd);
	return 0;
}