输入子系统 OK6410按键驱动

/**************************************************************************
* Author : Deadline_h
* Time   : 2017-3-4
* Brief  : This is a input system driver of OK6410 based on the 3.0.1 kernel
* 如果同样的事件，事件的值不变，只能上报一次。
**************************************************************************/
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/interrupt.h>
#include <linux/workqueue.h>
#include <linux/timer.h>
#include <asm/io.h>
#include <linux/input.h>

static int irq_flag[6] = {0};  //用于判断，是否注册中断成功。
struct timer_list my_timer;
static unsigned timer_flag = 0;
static struct input_dev * my_input_dev;

#define GPM_CON 0x7F008820
#define GPM_DAT 0x7F008824
#define GPN_CON 0x7F008830
#define GPN_DAT 0x7F008834
#define EINT0FLTCON0 0x7F008910

volatile unsigned long *gpfcon = NULL;
volatile unsigned long *gpfdat = NULL;
volatile unsigned long *gpncon = NULL;
volatile unsigned long *gpndat = NULL;

struct key_irq_dec{
    unsigned int irq;
    unsigned long flags;
    const char * name;
};

static struct key_irq_dec key_irq[]={
{IRQ_EINT(0),(IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING),"key1"},//key1 双边缘触发
{IRQ_EINT(1),(IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING),"key2"},//key2
{IRQ_EINT(2),(IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING),"key3"},//key3
{IRQ_EINT(3),(IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING),"key4"},//key4
{IRQ_EINT(4),(IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING),"key5"},//key5
{IRQ_EINT(5),(IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING),"key6"},//key6

};

static  void my_timer_func(void)
{
    unsigned int data = 0;
    timer_flag = 0;

    data = readl(gpndat);

    if((data&(1<<0))==0)//key1
    {
        printk(KERN_WARNING"key 1 down\n");
        input_event(my_input_dev,EV_KEY,KEY_0, 1); //上报事件

    }
    else
    {
        input_event(my_input_dev,EV_KEY,KEY_0, 0); //上报事件
    }
    /**************************************************************************/
    if((data&(1<<1))==0)//key2
    {
        printk(KERN_WARNING"key 2 down\n");
        input_event(my_input_dev,EV_KEY,KEY_1, 1); //上报事件
    }
    else
    {
        input_event(my_input_dev,EV_KEY,KEY_1, 0); //上报事件
    }
    /**************************************************************************/
    if((data&(1<<2))==0)//key3
    {
        printk(KERN_WARNING"key 3 down\n");
        input_event(my_input_dev,EV_KEY,KEY_L, 1); //上报事件
    }
    else
    {
        input_event(my_input_dev,EV_KEY,KEY_L, 0); //上报事件
    }
    /**************************************************************************/
    if((data&(1<<3))==0)//key4
    {
        printk(KERN_WARNING"key 4 down\n");
        input_event(my_input_dev,EV_KEY,KEY_S, 1); //上报事件
    }
    else
    {
        input_event(my_input_dev,EV_KEY,KEY_S, 0); //上报事件
    }
    /**************************************************************************/
    if((data&(1<<4))==0)//key5
    {
        printk(KERN_WARNING"key 5 down\n");
        input_event(my_input_dev,EV_KEY,KEY_LEFTSHIFT, 1); //上报事件
    }
    else
    {
        input_event(my_input_dev,EV_KEY,KEY_LEFTSHIFT, 0); //上报事件
    }
    /**************************************************************************/
    if((data&(1<<5))==0)//key6
    {
        printk(KERN_WARNING"key 6 down\n");
        input_event(my_input_dev,EV_KEY,KEY_ENTER, 1); //上报事件
    }
    else
    {
        input_event(my_input_dev,EV_KEY,KEY_ENTER, 0); //上报事件
    }
    /**************************************************************************/
    input_sync(my_input_dev);//上报同步事件，表示上报结束

}
static irqreturn_t key_irq_handler(int irq, void * dev_id)//interrupt handler
{
//  printk(KERN_WARNING"irq = %d , dev = %d\n",irq,dev_id);
    if(timer_flag == 0)
        mod_timer(&my_timer, jiffies + (1 * HZ) / 10);//启动定时器 定时器 100ms

    timer_flag = 1;


    return 0;  //中断处理函数要有返回值，不然内核会打印一些错误信息。

}


void key_hw_init(void)  //配置IO口为中断模式
{
    unsigned int data;

    gpncon= ioremap(GPN_CON,4);
    gpndat= ioremap(GPN_DAT,4);
    data = readl(gpncon);
    data &= ~((0b11<<0)|(0b11<<2)|(0b11<<4)|(0b11<<6)|(0b11<<8)|(0b11<<10));  //设置按键1与按键6
    data |= ((0b10<<0)|(0b10<<2)|(0b10<<4)|(0b10<<6)|(0b10<<8)|(0b10<<10));   //设置按键1与按键6
    writel(data,gpncon);
}

static int dri_init(void)
{
    unsigned int i = 0;
    unsigned int irq_retval = 0;
    key_hw_init();//将按键引脚配置为中断模式

    printk(KERN_WARNING "my input sys device register\n");


    my_input_dev = input_allocate_device();       //分配一个input_dev结构体


    set_bit(EV_KEY, my_input_dev->evbit);         //设置能产生什么类型的事件
    //set_bit(EV_REP, my_input_dev->evbit);         //设置能产生什么类型的事件


    set_bit(KEY_0,         my_input_dev->keybit); //设置能产生什么事件
    set_bit(KEY_1,         my_input_dev->keybit);
    set_bit(KEY_L,         my_input_dev->keybit);
    set_bit(KEY_S,         my_input_dev->keybit);
    set_bit(KEY_LEFTSHIFT, my_input_dev->keybit);
    set_bit(KEY_ENTER,     my_input_dev->keybit);


    input_register_device(my_input_dev); //注册input_dev


    init_timer(&my_timer);                       //初始化定时器
    my_timer.function = (void *)my_timer_func;
    add_timer(&my_timer);                        //添加定时器

    for(i=0;i<6;i++)//如果中断注册不成功，可能是因为该中断号已经注册过了，需要配置内核。或者设置成共享中断
    {
        irq_retval =    request_irq(key_irq[i].irq,key_irq_handler,key_irq[i].flags,key_irq[i].name,0); //注册中断
        if(irq_retval == 0)
        {
            irq_flag[i] = 0;
            //printk(KERN_WARNING"irq_%d request succeed\n",i);
        }

        else
        {
            irq_flag[i] = -1;
            printk(KERN_WARNING"irq_%d request failded,return val %d\n",i,irq_retval);
        }
    }
    return 0;
}


static void dri_exit(void)
{
    unsigned int i = 0;
    printk(KERN_WARNING "module delete\n");

    for(i=0;i<6;i++)
    {
        if(irq_flag[i] == 0)  //注册成功的中断才注销中断
            free_irq(key_irq[i].irq,0); //注销中断
    }

    del_timer(&my_timer); //删除定时器

    input_unregister_device(my_input_dev); //注销input_dev

    input_free_device(my_input_dev); //释放input_dev的内存

}


module_init(dri_init);
module_exit(dri_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Deadline_h");
MODULE_VERSION("V1.0");

应用测试程序：

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/select.h>
#include <sys/time.h>
#include <errno.h>
#include <linux/input.h>

int main(void)
{
    int fd;
    int key_value,i=0;
    struct input_event ev_key;

    fd = open("/dev/event2", O_RDWR);
    if (fd < 0) {
        printf("open failed\n");
        exit(1);
    }

    while(1)
    {
        read(fd,&ev_key,sizeof(struct input_event));
        if(EV_KEY==ev_key.type)
            printf("type:%d,code:%d,value:%d\n", ev_key.type,ev_key.code,ev_key.value);
        if(EV_SYN==ev_key.type)
            printf("syn event\n\n");

    }
    close(fd);
    return 0;
}