1.内部中断(0~31)
内部中断可以有4中触发方式
static struct irq_chip at91_aic_chip = {
.name = "AIC",
.irq_ack = at91_aic_mask_irq,
.irq_mask = at91_aic_mask_irq,
.irq_unmask = at91_aic_unmask_irq,
.irq_set_type = at91_aic_set_type,
.irq_set_wake = at91_aic_set_wake,
};
static int at91_aic_set_type(struct irq_data *d, unsigned type)
{
unsigned int smr, srctype;
switch (type) {
case IRQ_TYPE_LEVEL_HIGH:
srctype = AT91_AIC_SRCTYPE_HIGH;
break;
case IRQ_TYPE_EDGE_RISING:
srctype = AT91_AIC_SRCTYPE_RISING;
break;
case IRQ_TYPE_LEVEL_LOW:
if ((d->irq == AT91_ID_FIQ) || is_extern_irq(d->irq)) /* only supported on external interrupts */
srctype = AT91_AIC_SRCTYPE_LOW;
else
return -EINVAL;
break;
case IRQ_TYPE_EDGE_FALLING:
if ((d->irq == AT91_ID_FIQ) || is_extern_irq(d->irq)) /* only supported on external interrupts */
srctype = AT91_AIC_SRCTYPE_FALLING;
else
return -EINVAL;
break;
default:
return -EINVAL;
}
smr = at91_aic_read(AT91_AIC_SMR(d->irq)) & ~AT91_AIC_SRCTYPE;
at91_aic_write(AT91_AIC_SMR(d->irq), smr | srctype);
return 0;
}
2.外部中断(32~224)
外部中断有2种触发方式
static struct irq_chip gpio_irqchip = {
.name = "GPIO",
.irq_disable = gpio_irq_mask,
.irq_mask = gpio_irq_mask,
.irq_unmask = gpio_irq_unmask,
.irq_set_type = gpio_irq_type,
.irq_set_wake = gpio_irq_set_wake,
};
static int gpio_irq_type(struct irq_data *d, unsigned type)
{
switch (type) {
case IRQ_TYPE_NONE:
case IRQ_TYPE_EDGE_BOTH:
return 0;
default:
return -EINVAL;
}
}