imx6ul gpio中断接收（代码）

痛定思痛。 2022-12-30 04:59 160阅读 0赞

gpio这里的调试要注意的是管脚的功能配置，需要更改设备树文件；

更改设备树文件：[https://blog.csdn.net/cao849861802/article/details/111604277][https_blog.csdn.net_cao849861802_article_details_111604277]

然后注意gpio的计算比如gpio2\_8

（2-1）\*32 + 8 = 40

这个计算公式可以算出操作的gpio管脚是哪个。

#include "fcntl.h"
    #include "stdio.h"
    #include "poll.h"
    #include "string.h"
    #include "stdlib.h"
    #include "unistd.h"
    
    
    
    
    #define GPIO_EXPORT_BASE 118
    #define GPIO_KEY_NUMBER   6
    
    
    
    void edgfdinit()
    {
    	char buf[64];
    	int i = 0;
    	int edgfd;
    	int len = 0;
    	int ret ;
    	
    	for(i = 0; i < GPIO_KEY_NUMBER; i++)
    	{
    		memset(buf,0,sizeof(buf));
    		sprintf(buf,"echo %d > /sys/class/gpio/export",GPIO_EXPORT_BASE + i);
    		ret = system(buf);
    		if(ret < 0)
    		{
    			printf("system %s failed\r\n",buf);
    			continue;
    		}
    		
    		memset(buf,0,sizeof(buf));
    		sprintf(buf,"/sys/class/gpio/gpio%d/edge",GPIO_EXPORT_BASE + i);
    		edgfd = open(buf,O_RDWR);
    		if(edgfd < 0)
    		{
    			printf("open %s failed\r\n",buf);
    			continue;
    		}
    		
    		len = write(edgfd,"falling",strlen("falling"));
    		if(len < strlen("falling"))
    		{
    			printf("write edgfd falling failed GPIO = %d\r\n",i + GPIO_EXPORT_BASE);
    			close(edgfd);
    			continue;
    		}
    	}
    }
    
    
    
    
    void main()
    {
    	int i = 0;
    	char buf[64];
    	int ret ;
    	struct pollfd fds[GPIO_KEY_NUMBER];
    	
    	printf("gpio task start\r\n");
    	edgfdinit();
    	
    	for(i = 0; i < GPIO_KEY_NUMBER; i++)
    	{
    		memset(buf,0,sizeof(buf));
    		sprintf(buf,"/sys/class/gpio/gpio%d/value",GPIO_EXPORT_BASE + i);
    		fds[i].fd = open(buf,O_RDONLY);
    		if(fds[i].fd < 0)
    		{
    			printf("open fd %s failed\r\n",buf);
    			continue;
    		}
    		fds[i].events = POLLPRI;
    	}
    	
    	while(1)
    	{
    		ret = poll(fds,GPIO_KEY_NUMBER,-1);
    		if(ret < 0)
    		{
    			printf("poll fds failed \r\n");
    			return ;
    		}
    		
    		for(i = 0; i < GPIO_KEY_NUMBER; i++)
    		{	
    			if(fds[i].revents & POLLPRI)
    			{
    				printf("get fd is %d\r\n",fds[i].fd);
    				ret = lseek(fds[i].fd,0,SEEK_SET);
    				if(ret < 0)
    				{
    					printf("lseek seek_set failed i = %d\r\n",i);
    					return ;
    				}
    				
    				memset(buf,0,sizeof(buf));
    				ret = read(fds[i].fd,buf,1);
    				if(ret < 0)
    				{
    					printf("read fds.fd failed\r\n");
    					return ;
    				}
    				
    				printf("the key %d is %s",i,buf);
    			}			
    		}
    	}
    }

[https_blog.csdn.net_cao849861802_article_details_111604277]: https://blog.csdn.net/cao849861802/article/details/111604277