查询方式的按键驱动程序
2016-06-01 09:08
169 查看
#include <linux/module.h> #include <linux/kernel.h> #include <linux/fs.h> #include <linux/init.h> #include <linux/delay.h> #include <asm/uaccess.h> #include <asm/irq.h> #include <asm/io.h> #include <asm/arch/regs-gpio.h> #include <asm/hardware.h> static struct class *seconddrv_class; static struct class_device *seconddrv_class_dev; volatile unsigned long *gpfcon; volatile unsigned long *gpfdat; volatile unsigned long *gpgcon; volatile unsigned long *gpgdat; static int second_drv_open(struct inode *inode, struct file *file) { /* 配置GPF0,2为输入引脚 */ *gpfcon &= ~((0x3<<(0*2)) | (0x3<<(2*2))); /* 配置GPG3,11为输入引脚 */ *gpgcon &= ~((0x3<<(3*2)) | (0x3<<(11*2))); return 0; } ssize_t second_drv_read(struct file *file, char __user *buf, size_t size, loff_t *ppos) { /* 返回4个引脚的电平 */ unsigned char key_vals[4]; int regval; if (size != sizeof(key_vals)) return -EINVAL; /* 读GPF0,2 */ regval = *gpfdat; key_vals[0] = (regval & (1<<0)) ? 1 : 0; key_vals[1] = (regval & (1<<2)) ? 1 : 0; /* 读GPG3,11 */ regval = *gpgdat; key_vals[2] = (regval & (1<<3)) ? 1 : 0; key_vals[3] = (regval & (1<<11)) ? 1 : 0; copy_to_user(buf, key_vals, sizeof(key_vals)); //函数原型: //unsigned long copy_to_user(void *to, const void __user *from, usigned long count); //unsigned long copy_from_user(void __user *to, const void *from, usigned long count); return sizeof(key_vals); } static struct file_operations sencod_drv_fops = { .owner = THIS_MODULE, /* 这是一个宏,推向编译模块时自动创建的__this_module变量 */ .open = second_drv_open, .read = second_drv_read, }; int major; static int second_drv_init(void) { major = register_chrdev(0, "second_drv", &sencod_drv_fops); seconddrv_class = class_create(THIS_MODULE, "second_drv"); seconddrv_class_dev = class_device_create(seconddrv_class, NULL, MKDEV(major, 0), NULL, "buttons"); /* /dev/buttons */ gpfcon = (volatile unsigned long *)ioremap(0x56000050, 16); gpfdat = gpfcon + 1; gpgcon = (volatile unsigned long *)ioremap(0x56000060, 16); gpgdat = gpgcon + 1; return 0; } static void second_drv_exit(void) { unregister_chrdev(major, "second_drv"); class_device_unregister(seconddrv_class_dev); class_destroy(seconddrv_class); iounmap(gpfcon); iounmap(gpgcon); return 0; } module_init(second_drv_init); module_exit(second_drv_exit); MODULE_LICENSE("GPL");
EINT0---F0
EINT2---F2
EINT11-G3
EINT19-G11
测试程序:
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdio.h>
/* seconddrvtest
*/
int main(int argc, char **argv)
{
int fd;
unsigned char key_vals[4];
int cnt = 0;
fd = open("/dev/buttons", O_RDWR);
if (fd < 0)
{
printf("can't open!\n");
}
while (1)
{
read(fd, key_vals, sizeof(key_vals));
if (!key_vals[0] || !key_vals[1] || !key_vals[2] || !key_vals[3])
{
printf("%04d key pressed: %d %d %d %d\n", cnt++, key_vals[0], key_vals[1], key_vals[2], key_vals[3]);
}
}
return 0;
}
相关文章推荐
- MINI2440按键驱动详解
- mini2440按键驱动
- jz2440 的中断中的底半部机制
- 飞凌ok6410开发板的按键驱动改程序
- 一步一步学习 Linux 驱动之 platform 机制(tiny210 按键驱动)
- 第二个驱动程序-tq2440
- 第六个驱动程序-tq2440
- 第7个驱动程序
- Linux按键驱动程序设计详解---从简单到不简单
- linux-2.6.32在mini2440开发板上移植(17)之按键驱动程序移植
- i.MX53 GPIO 按键驱动
- tq2440 按键驱动 中断方式(转)
- linuxfl2440开发板驱动开发之按键驱动
- 中断按键驱动程序
- Linux开发九_按键驱动
- 输入子系统(3):按键驱动实现
- 基于tiny4412按键中断编程
- 47 使用linux内核源码里的按键驱动<GPIO Buttons>
- 按键驱动分析
- 按键驱动测试程序