For some devices the IRQ trigger type for a device is read from firmware, such as device-tree. The IRQ trigger type is typically read when the mapping for IRQ is created, which is before the IRQ is requested. Hence, the IRQ trigger type is programmed when mapping the IRQ and not when requesting the IRQ. Although this works for most cases, in order to support IRQ chips which require runtime power management, which may not be accessible prior to requesting the IRQ, it is desirable to look-up the IRQ trigger type when it is requested. Therefore, if the IRQ trigger type is not specified when __setup_irq() is called, look-up the saved IRQ trigger type. This will allow us to defer the programming of the trigger type from when the IRQ is mapped to when it is actually requested. Signed-off-by: Jon Hunter <jonathanh@xxxxxxxxxx> Reviewed-by: Marc Zyngier <marc.zyngier@xxxxxxx> --- kernel/irq/manage.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index ef0bc02c3a70..eaedeb74b49d 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -1117,6 +1117,13 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) new->irq = irq; /* + * If the trigger type is not specified by the caller, + * then use the default for this interrupt. + */ + if (!(new->flags & IRQF_TRIGGER_MASK)) + new->flags |= irqd_get_trigger_type(&desc->irq_data); + + /* * Check whether the interrupt nests into another interrupt * thread. */ -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
