enable_irq 使能IRQ中断处理 系统睡眠时不能使能 enable handling of an irq

enable_irq_wake 中断唤醒功能，多用于指纹、光感传感器唤醒系统用 control irq power management wakeup，Wakeup mode lets this IRQ wake the system from sleep

 

/**
 *	enable_irq - enable handling of an irq
 *	@irq: Interrupt to enable
 *
 *	Undoes the effect of one call to disable_irq().  If this
 *	matches the last disable, processing of interrupts on this
 *	IRQ line is re-enabled.
 *
 *	This function may be called from IRQ context only when
 *	desc->irq_data.chip->bus_lock and desc->chip->bus_sync_unlock are NULL !
 */
void enable_irq(unsigned int irq)
{
	unsigned long flags;
	struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);

	if (!desc)
		return;
	if (WARN(!desc->irq_data.chip,
		 KERN_ERR "enable_irq before setup/request_irq: irq %u\n", irq))
		goto out;

	__enable_irq(desc);
out:
	irq_put_desc_busunlock(desc, flags);
}

 

static inline int enable_irq_wake(unsigned int irq)
{
	return irq_set_irq_wake(irq, 1);
}
/**
 *	irq_set_irq_wake - control irq power management wakeup
 *	@irq:	interrupt to control
 *	@on:	enable/disable power management wakeup
 *
 *	Enable/disable power management wakeup mode, which is
 *	disabled by default.  Enables and disables must match,
 *	just as they match for non-wakeup mode support.
 *
 *	Wakeup mode lets this IRQ wake the system from sleep
 *	states like "suspend to RAM".
 */
 int irq_set_irq_wake(unsigned int irq, unsigned int on)
{
	unsigned long flags;
	struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
	int ret = 0;

	if (!desc)
		return -EINVAL;

	/* wakeup-capable irqs can be shared between drivers that
	 * don't need to have the same sleep mode behaviors.
	 */
	if (on) {
		if (desc->wake_depth++ == 0) {
			ret = set_irq_wake_real(irq, on);
			if (ret)
				desc->wake_depth = 0;
			else
				irqd_set(&desc->irq_data, IRQD_WAKEUP_STATE);
		}
	} else {
		if (desc->wake_depth == 0) {
			WARN(1, "Unbalanced IRQ %d wake disable\n", irq);
		} else if (--desc->wake_depth == 0) {
			ret = set_irq_wake_real(irq, on);
			if (ret)
				desc->wake_depth = 1;
			else
				irqd_clear(&desc->irq_data, IRQD_WAKEUP_STATE);
		}
	}
	irq_put_desc_busunlock(desc, flags);
	return ret;
}