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s3c6410外部中断号与引脚问题

在编写Linux驱动程序时。我想用某一个引脚做外部中断。可是在调用

int request_irq(unsigned int irq, 
void (*handler)(int irq, void *dev_id, struct pt_regs *regs 
),
unsigned long irqflags, 
const char * devname, 
void *dev_id); 

这个函数的时候遇到了一个问题,irq是个硬件终端号,可是究竟这个引脚相应的终端号是多少呢?

我在网上找资料说的都稀里糊涂的,不是我想要的答案。

于是我便在内核代码里找,以下贴出Linux内核代码的一段arch\arm\mach-s3c64xx\include\mach\Irqs.h,能够解释这个问题:

/* Since the IRQ_EINT(x) are a linear mapping on current s3c64xx series
 * we just defined them as an IRQ_EINT(x) macro from S3C_IRQ_EINT_BASE
 * which we place after the pair of VICs. */

#define S3C_IRQ_EINT_BASE	S3C_IRQ(64+5)

#define S3C_EINT(x)		((x) + S3C_IRQ_EINT_BASE)
#define IRQ_EINT(x)		S3C_EINT(x)
#define IRQ_EINT_BIT(x)		((x) - S3C_EINT(0))

/* Next the external interrupt groups. These are similar to the IRQ_EINT(x)
 * that they are sourced from the GPIO pins but with a different scheme for
 * priority and source indication.
 *
 * The IRQ_EINT(x) can be thought of as ‘group 0‘ of the available GPIO
 * interrupts, but for historical reasons they are kept apart from these
 * next interrupts.
 *
 * Use IRQ_EINT_GROUP(group, offset) to get the number for use in the
 * machine specific support files.
 */

#define IRQ_EINT_GROUP1_NR	(15)
#define IRQ_EINT_GROUP2_NR	(8)
#define IRQ_EINT_GROUP3_NR	(5)
#define IRQ_EINT_GROUP4_NR	(14)
#define IRQ_EINT_GROUP5_NR	(7)
#define IRQ_EINT_GROUP6_NR	(10)
#define IRQ_EINT_GROUP7_NR	(16)
#define IRQ_EINT_GROUP8_NR	(15)
#define IRQ_EINT_GROUP9_NR	(9)

#define IRQ_EINT_GROUP_BASE	S3C_EINT(28)
#define IRQ_EINT_GROUP1_BASE	(IRQ_EINT_GROUP_BASE + 0x00)
#define IRQ_EINT_GROUP2_BASE	(IRQ_EINT_GROUP1_BASE + IRQ_EINT_GROUP1_NR)
#define IRQ_EINT_GROUP3_BASE	(IRQ_EINT_GROUP2_BASE + IRQ_EINT_GROUP2_NR)
#define IRQ_EINT_GROUP4_BASE	(IRQ_EINT_GROUP3_BASE + IRQ_EINT_GROUP3_NR)
#define IRQ_EINT_GROUP5_BASE	(IRQ_EINT_GROUP4_BASE + IRQ_EINT_GROUP4_NR)
#define IRQ_EINT_GROUP6_BASE	(IRQ_EINT_GROUP5_BASE + IRQ_EINT_GROUP5_NR)
#define IRQ_EINT_GROUP7_BASE	(IRQ_EINT_GROUP6_BASE + IRQ_EINT_GROUP6_NR)
#define IRQ_EINT_GROUP8_BASE	(IRQ_EINT_GROUP7_BASE + IRQ_EINT_GROUP7_NR)
#define IRQ_EINT_GROUP9_BASE	(IRQ_EINT_GROUP8_BASE + IRQ_EINT_GROUP8_NR)

#define IRQ_EINT_GROUP(group, no)	(IRQ_EINT_GROUP##group##_BASE + (no))

从以上凝视以及代码能够看到。有两个宏来获得终端号,

IRQ_EINT(x)                                                第0组

IRQ_EINT_GROUP(group,no)          第1-9组





s3c6410外部中断号与引脚问题