内核中断
#include <linux/interrupt.h>
int request_irq(unsigned int irq, irq_handler_t handler,
unsigned long irqflags, const char *devname, void *dev_id)
irq:
中断号 arch/arm/mach-s3c64xx/include/mach/irqs.h
handler:
中断处理函数 irqreturn_t handler(int irq, void *dev_id);
irqreturn_t:
See include/linux/irqreturn.h
irqflags:
See line 21-59 in include/linux/interrupt.h
使用IRQF_SHARED共享irq时, irqflags必须相同
如: request_irq(IRQ_EINT(0), handler1,
IRQF_TRIGGER_FALLING | IRQF_SHARED, "dev1", &dev1);
request_irq(IRQ_EINT(0), handler2,
IRQF_TRIGGER_FALLING | IRQF_SHARED, "dev2", &dev2);
devname:
设备名, cat /proc/interrupts
dev_id:
发生中断时将dev_id传递给handler函数,
irqflags含有IRQF_SHARED时dev_id不能为NULL, 并且要保证唯一
dev_id一般采用当前设备的结构体指针
void free_irq ( unsigned int irq, void * dev_id);
释放匹配irq和dev_id的中断, 如果irq有多个相同的dev_id, 将释放第一个
So, 共享中断的dev_id不是唯一时, 可能会释放到其它设备的中断
void disable_irq(unsigned int irq);
关闭irq号中断
void enable_irq(unsigned int irq);
开启irq号中断
void local_irq_save(unsigned long flags);
关闭当前CPU中断并保存当前状态到flags
void local_irq_restore(unsigned long flags);
恢复flags到当前CPU
void local_irq_disable(void);
关闭当前CPU中断
void local_irq_enable(void);
开启当前CPU中断
注: 没有关闭和开启所有CPU中断的函数(没必要)
