arm 驱动linux内核驱动之中断下半部编程

}
myvirtualdisk->mycdevclassdevice = class_device_create(myvirtualdisk->mycdevclass, NULL, MKDEV(major, 0), NULL, "mynewdriver");
if(IS_ERR(myvirtualdisk->mycdevclassdevice)){
ret = PTR_ERR(myvirtualdisk->mycdevclassdevice);
printk(KERN_ERR "class_device_create failed!\n");
goto release_class_create;
}

cdev_init(&(myvirtualdisk->mycdev), &mydev_fops);
myvirtualdisk->mycdev.owner = THIS_MODULE;
ret = cdev_add(&myvirtualdisk->mycdev, MKDEV(major, 0), 1);

//这里把timer相关的放在irq前面，不然会有bug出现(当在insmod时候按下按钮就会出错)
init_timer(&myvirtualdisk->mytimer);
myvirtualdisk->mytimer.function = mytimer_func;
myvirtualdisk->mytimer.data = (unsigned long)myvirtualdisk;

if(ret < 0){
goto release_device_class_create;
}
for(i = 0; i < 3; i++)
{
ret = request_irq(gpio_to_irq(myirq_descs[i].irq_id), myirq_handle, IRQF_TRIGGER_FALLING, myirq_descs[i].irq_name, &myirq_descs[i]);
if(ret < 0){
printk(KERN_ERR "request irq failed!\n");
ret =-EFAULT;
goto release_cdevandtimer;
}
}

return 0;
release_cdevandtimer:
del_timer(&myvirtualdisk->mytimer);
cdev_del(&myvirtualdisk->mycdev);
release_device_class_create:
class_device_unregister(myvirtualdisk->mycdevclassdevice);
release_class_create:
class_destroy(myvirtualdisk->mycdevclass);
release_mem_malloc:
kfree(myvirtualdisk);
release_chrdev:
unregister_chrdev_region(MKDEV(major, 0), 1);
return ret;
}

static void __exit cdevtest_exit(void){
int i = 0;
printk("*******%s****1****\n", __FUNCTION__);
del_timer(&myvirtualdisk->mytimer);
printk("*******%s*****2***\n", __FUNCTION__);
for(i = 0; i < 3; i++)free_irq(gpio_to_irq(myirq_descs[i].irq_id), &myirq_descs[i]);
printk("*******%s*****3***\n", __FUNCTION__);
cdev_del(&myvirtualdisk->mycdev);
printk("*******%s*****4***\n", __FUNCTION__);
class_device_unregister(myvirtualdisk->mycdevclassdevice);
printk("*******%s*****5***\n", __FUNCTION__);
class_destroy(myvirtualdisk->mycdevclass);
printk("*******%s*****6***\n", __FUNCTION__);
kfree(myvirtualdisk);
printk("*******%s********\n", __FUNCTION__);
unregister_chrdev_region(MKDEV(major, 0), 1);
printk("*******%s*****7***\n", __FUNCTION__);
}

module_init(cdevtest_init);
module_exit(cdevtest_exit);
MODULE_LICENSE("GPL");

完整的tasklet任务中断上下半部代码

#include
#include
#include
#include
#include
#include
#include
#include
#include

#include
#include
#include
#define VIRTUAL_MAJOR 250
int major = VIRTUAL_MAJOR;

struct myirq_desc{
int irq_id;
char *irq_name;
int irq_code;
};

struct myirq_desc myirq_descs[3]= {
{S3C2410_GPF0, "s2", KEY_J},
{S3C2410_GPF2, "s3", KEY_K},
{S3C2410_GPG3, "s4", KEY_Z},
};
struct VirtualDisk{
struct class *mycdevclass;//在/sys/class创建类
struct class_device *mycdevclassdevice;//在/dev下创建设备
struct cdev mycdev;//给设备添加相关的fileoption
struct timer_list mytimer;
struct tasklet_struct mytasklet;
};
struct VirtualDisk *myvirtualdisk;

static struct file_operations mydev_fops = {
.owner = THIS_MODULE,
};
static void mytasklet_func(unsigned long fundata){
printk("*****%s******,date = %ld\n", __FUNCTION__, fundata);
}
static void mytimer_func(unsigned long fundata){
printk("*******%s********\n", __FUNCTION__);
struct VirtualDisk *myvirtualdisk_fun = (struct VirtualDisk *)(fundata);
//myvirtualdisk_fun->mytimer.expires =jiffies + 2 * HZ;
//add_timer(&myvirtualdisk_fun->mytimer);
printk("timer func happened!\n");
}
static irqreturn_t myirq_handle(int irq, void *dev_id){
struct myirq_desc *myirq_descone = (struct myirq_desc *)dev_id;
printk("*******%s********\n", __FUNCTION__);
printk("irq = %d, irq_id = %d,irq_name = %s, irq_code = %c\n", irq, myirq_descone->irq_id, myirq_descone->irq_name, myirq_descone->irq_code);
tasklet_schedule(&myvirtualdisk->mytasklet);//激发任务，将mytasklet_func加入系统任务
mod_timer(&myvirtualdisk->mytimer, jiffies + 2*HZ);
return IRQ_RETVAL(IRQ_HANDLED);
}