linux驱动定时器实现按键按下打印字符

#include <linux/init.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include <linux/interrupt.h>struct device_node *dev;
unsigned int irqno;
//中断处理函数
irqreturn_t myirq_handler(int irq,void *dev)
{printk("KET1_INTERRUPT\n");return IRQ_HANDLED;
}static int __init mycdev_init(void)
{//解析按键的设备树节点dev = of_find_node_by_path("/myirq");if(dev == NULL){printk("解析设备树节点失败\n");return -EFAULT;}printk("解析设备树节点成功\n");//根据设备树节点解析出软中断号irqno = irq_of_parse_and_map(dev,0); //按键1索引号为0if(!irqno){printk("解析软中断号失败\n");return -ENXIO;}printk("解析软中断号成功 irqno=%d\n",irqno);//注册中断int ret;ret = request_irq(irqno,myirq_handler,IRQF_TRIGGER_FALLING,"key1",NULL);if(ret){printk("注册中断失败\n");return ret;}printk("注册中断成功\n");return 0;
}
static void __exit mycdev_exit(void)
{//注销中断free_irq(irqno,NULL);}
module_init(mycdev_init);
module_exit(mycdev_exit);
MODULE_LICENSE("GPL");

设备树