6410之输入子系统（2）

编写代码可以参考:Gpio_keys.c (drivers\input\keyboard)

代码如下：

#include <linux/module.h>#include <linux/init.h>#include <linux/fs.h>#include <linux/interrupt.h>#include <linux/irq.h>#include <linux/sched.h>#include <linux/pm.h>#include <linux/slab.h>#include <linux/sysctl.h>#include <linux/proc_fs.h>#include <linux/delay.h>#include <linux/platform_device.h>#include <linux/input.h>#include <linux/gpio_keys.h>#include <linux/workqueue.h>#include <linux/gpio.h>struct input_dev *buttons_dev;struct timer_list buttons_timer;struct pin_desc * irq_pd;struct pin_desc{unsigned int pin;unsigned int irq;unsigned char *name;unsigned int key_val;};struct pin_desc pins_desc[4] = {{S3C64XX_GPN(0),IRQ_EINT(0),"L",KEY_L},{S3C64XX_GPN(1),IRQ_EINT(1),"S",KEY_S},{S3C64XX_GPN(2),IRQ_EINT(2),"Enter",KEY_ENTER},{S3C64XX_GPN(3),IRQ_EINT(3),"LeftShift",KEY_LEFTSHIFT},};void buttons_timer_function(unsigned long data){struct pin_desc * pindesc = irq_pd;unsigned int pinval;if (!pindesc)return;pinval = gpio_get_value(pindesc->pin);if (pinval){/* 松开 : 最后一个参数: 0-松开, 1-按下 */input_event(buttons_dev, EV_KEY, pindesc->key_val, 0);input_sync(buttons_dev);}else{/* 按下 */input_event(buttons_dev, EV_KEY, pindesc->key_val, 1);input_sync(buttons_dev);}}static irqreturn_t buttons_irq(int irq, void *dev_id){/* 10ms后启动定时器 */irq_pd = (struct pin_desc *)dev_id;mod_timer(&buttons_timer, jiffies+HZ/100);return IRQ_RETVAL(IRQ_HANDLED);}static int buttons_init(void){int i;/* 1. 分配一个input_dev结构体*/buttons_dev = input_allocate_device();;/* 2. 设置 *//* 2.1 设置使用那类事件 */set_bit(EV_KEY, buttons_dev->evbit);set_bit(EV_REP, buttons_dev->evbit);/* 2.2 能产生这类事件的哪些事件: L,S,ENTER,LEFTSHIT */set_bit(KEY_L, buttons_dev->keybit);  //字母"L"set_bit(KEY_S, buttons_dev->keybit);  //字母"S"set_bit(KEY_ENTER, buttons_dev->keybit);  //Enter键set_bit(KEY_LEFTSHIFT, buttons_dev->keybit);  // 左边的shift按键/* 3. 注册 */input_register_device(buttons_dev);/* 4. 硬件相关的操作 */init_timer(&buttons_timer);//初始化定时器buttons_timer.function = buttons_timer_function;//定时器处理函数add_timer(&buttons_timer);//将定时器告诉内核for (i = 0; i < 4; i++){request_irq(pins_desc[i].irq, buttons_irq, IRQF_TRIGGER_FALLING|IRQF_TRIGGER_RISING, pins_desc[i].name, &pins_desc[i]);}return 0;}static void buttons_exit(void){int i;for (i = 0; i < 4; i++){free_irq(pins_desc[i].irq, &pins_desc[i]);}del_timer(&buttons_timer);input_unregister_device(buttons_dev);input_free_device(buttons_dev);}module_init(buttons_init);module_exit(buttons_exit);MODULE_LICENSE("GPL");

执行：

/test # exec 0</dev/tty1
按下按键就会出现下面的现象：

/test # ls