经典博文
文章链接备注linux中断申请之request_threaded_irqhttps://www.cnblogs.com/dirt2/p/5632061.html明确两种方式的优缺点linux驱动request_threaded_irq()https://blog.csdn.net/gx19862005/article/details/18740705中断原理清晰
实践总结
在wiegand驱动开发过程中,自测试时,一边发送一边接受,那么在发送两个信号间的时间,需要处理完一个中断,否则会出现中断丢失。如果是从wiegand设备接受信号,同样的要求。按照wiegand协议,两个信号间时间是很短的,在开发中刚开始使用request_irq处理中断,系统占用资源稍高,就会出现中断丢失,替换为request_threaded_irq,很好的解决了时效问题。
总结: request_threaded_irq:中断处理线程化,很好解决高频率的中断响应,类似异步处理 request_irq:类似于同步处理事务,适合非高频率中断响应。
Demo
irqreturn_t irq_thread_handler(int irq, void *dev_id)
{
st_itech_led_dev* dev = (st_itech_led_dev*)dev_id;
print_dbg("irq = %d, dev->crtl_irq: %d", irq, dev->crtl_irq);
if(irq != dev->crtl_irq) {
return IRQ_NONE;
}
dev->occur_irq = true;
udelay(500);
dev->irq_result = gpio_get_value(dev->ctrl_gpio);
print_dbg("gpio_level: %d", gpio_get_value(dev->ctrl_gpio));
print_dbg("irq_result: %d", dev->irq_result);
wake_up_interruptible(&led_irq_in_waitq);
return IRQ_HANDLED;
}
irqreturn_t sensor_irq_handler(int irq, void *dev_id)
{
return IRQ_WAKE_THREAD;
}
static void init_light_sensor_irq(st_itech_led_dev* dev)
{
int ret = -1;
int irq_tmp = gpio_to_irq(dev->ctrl_gpio);
if (ENXIO == irq_tmp) {
print_err("get irq num failed.\n");
return;
}
dev->crtl_irq = irq_tmp;
print_info("request led(%d) sensor irq(%d)", dev->param.num, irq_tmp);
ret = request_threaded_irq(irq_tmp, sensor_irq_handler, irq_thread_handler,
IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING, "light_sensor_irq_up", dev);
if (ret) {
print_err("request_threaded_irq irq_rising_handler ERROR!!!\n");
return ;
}
}
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