request_irq

warning: passing arg 2 of `request_irq' from incompatible pointer type

linux-2.6.24/include/linux/interrupt.h
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extern int __must_check request_irq(unsigned int, irq_handler_t handler,
               unsigned long, const char *, void *);


typedef irqreturn_t (*irq_handler_t)(int, void *);


linux-2.6.10/include/linux/interrupt.h
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extern int request_irq(unsigned int,
               irqreturn_t (*handler)(int, void *, struct pt_regs *),
               unsigned long, const char *, void *);



request_irq()返回-16
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#define EBUSY 16 /* Device or resource busy */
表示中断已经被使用




中断处理程序的返回值
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/*
* IRQ_NONE means we didn't handle it.
* IRQ_HANDLED means that we did have a valid interrupt and handled it.
* IRQ_RETVAL(x) selects on the two depending on x being non-zero (for handled)
*/
typedef int irqreturn_t;

#define IRQ_NONE        (0)
#define IRQ_HANDLED     (1)
#define IRQ_RETVAL(x)   ((x) != 0)