/节点下添加
key_irq {
compatible = “alientek,key”;
pinctrl-0 = <&key_irq_gpio>;
pinctrl-names = “alientek,key”;
misckey-gpio = <&gpio3 RK_PD2 GPIO_ACTIVE_HIGH>;
status = “okay”;
};
pinctr中添加
key-irq-gpios {
/omit-if-no-ref/
key_irq_gpio: key-irq-pin {
rockchip,pins = <3 RK_PD2 RK_FUNC_GPIO &pcfg_pull_none>;
};
};
————————驱动———————————————–
#include
#include
#include
#define MISCKEY_NAME “misckey_irq” /* 名字 */
#define MISCKEY_MINOR 255 /* 子设备号 */
/* miscled设备结构体 */
struct misckey_dev{
dev_t devid; /* 设备号 */
struct cdev cdev; /* cdev */
struct class *class; /* 类 */
struct device *device; /* 设备 */
int key_gpio; /* led所使用的GPIO编号 */
int keyvalue;
};
struct misckey_dev misckey; /* led设备 */
static int misckey_open(struct inode *inode, struct file *filp)
{
struct misckey_dev *dev = filp->private_data;
filp->private_data = &misckey; /* 设置私有数据 */
dev = filp->private_data;
printk(“open misckey.key_gpio=%d\n”, dev->key_gpio);
return 0;
}
static ssize_t misckey_write(struct file *filp, const char __user *buf, size_t cnt, loff_t *offt)
{
return 0;
}
static ssize_t misckey_read(struct file *filp, char __user *buf, size_t cnt, loff_t *offt)
{
int ret = 0;
int value;
struct misckey_dev *dev = filp->private_data;
printk(“misckey_read = %d\n”,dev->key_gpio);
if (gpio_get_value(dev->key_gpio) == 1)
{
printk(“misckey_read = 1\n”);
dev->keyvalue=1;
}
else
{
printk(“misckey_read = 0\n”);
dev->keyvalue=0;
}
value = dev->keyvalue;
ret = copy_to_user(buf, &value, sizeof(value));
return ret;
}
/*
* file operations
*/
/* 设备操作函数 */
static struct file_operations mykey_fops = {
.owner = THIS_MODULE,
.open = misckey_open,
.read = misckey_read,
.write = misckey_write,
};
/* MISC设备结构体 */
static struct miscdevice mykey_miscdev = {
.minor = MISCKEY_MINOR,
.name = MISCKEY_NAME,
.fops = &mykey_fops,
};
static int led_gpio_init(struct device_node *nd)
{
int ret;
/* 从设备树中获取GPIO */
misckey.key_gpio = of_get_named_gpio(nd, “misckey-gpio”, 0);
printk(“misckey.key_gpio=%d\n”,misckey.key_gpio);
if(!gpio_is_valid(misckey.key_gpio))
{
printk(“miscled：Failed to get key-gpio\n”);
return -EINVAL;
}
/* 申请使用GPIO */
ret = gpio_request(misckey.key_gpio, “key_irq”);
if(ret)
{
printk(“led: Failed to request misckey-gpio\n”);
return ret;
}
ret = gpio_direction_input(misckey.key_gpio);
if(ret < 0) {
printk("can't set gpio!\r\n");
return ret;
}
return 0;
}
static int mykey_probe(struct platform_device *pdev)
{
int ret;
printk("misc_my_key driver and device was matched!\r\n");
ret = led_gpio_init(pdev->dev.of_node);
if(ret < 0)
{
printk("gpio_init error!\r\n");
return ret;
}
else
{
printk("gpio_init success!\r\n");
}
ret = misc_register(&mykey_miscdev);
if(ret < 0){
printk("misc device register failed!\r\n");
goto free_gpio;
}
else
{
printk("misc device register success!\r\n");
}
return 0;
free_gpio:
gpio_free(misckey.key_gpio);
return -EINVAL;
return 0;
}
/*
* @description : platform驱动的remove函数
* @param - dev : platform设备
* @return : 0，成功;其他负值,失败
*/
static int mykey_remove(struct platform_device *dev)
{
gpio_free( misckey.key_gpio);
/* 注销misc设备 */
misc_deregister(&mykey_miscdev);
return 0;
}
/* 匹配列表 */
static const struct of_device_id key_of_match[] = {
{ .compatible = "alientek,key" },
{ /* Sentinel */ }
};
/* platform驱动结构体 */
static struct platform_driver mykey_misc = {
.driver = {
.name = "alientek,key", /* 驱动名字，用于和设备匹配 */
.of_match_table = key_of_match, /* 设备树匹配表 */
},
.probe = mykey_probe,
.remove = mykey_remove,
};
static int mykey_init(void)
{
int ret = 0;
printk(" mykey_init enter\n");
ret = platform_driver_register(&mykey_misc);
if(ret != 0)
printk("mykey_init register failed!");
return 0;
}
static void mykey_exit(void)
{
printk(" Hello World exit\n ");
platform_driver_unregister(&mykey_misc);
}
module_init(mykey_init);
module_exit(mykey_exit);
MODULE_LICENSE("Dual BSD/GPL");
MODULE_DESCRIPTION("A simple Hello World Module");
--------------------------应用程序------------------------------------
#include "stdio.h"
#include "unistd.h"
#include "sys/types.h"
#include "sys/stat.h"
#include "fcntl.h"
#include "stdlib.h"
#include "string.h"
/* 定义按键值 */
#define KEY0VALUE 0XF0
#define INVAKEY 0X00
/*
* @description : main主程序
* @param - argc : argv数组元素个数
* @param - argv : 具体参数
* @return : 0 成功;其他 失败
*/
int main(int argc, char *argv[])
{
int fd, ret;
char *filename;
int keyvalue;
if(argc != 2){
printf("Error Usage!\r\n");
return -1;
}
filename = argv[1];
/* 打开key驱动 */
fd = open(filename, O_RDWR);
if(fd < 0){
printf("file %s open failed!\r\n", argv[1]);
return -1;
}
/* 循环读取按键值数据！ */
while(1) {
read(fd, &keyvalue, sizeof(keyvalue));
if (keyvalue == KEY0VALUE)
{ /* KEY0 */
printf("KEY0 Press, value = %#X\r\n", keyvalue); /* 按下 */
}
sleep(1);
}
ret= close(fd); /* 关闭文件 */
if(ret < 0){
printf("file %s close failed!\r\n", argv[1]);
return -1;
}
return 0;
}