Commit 1984e075 authored Sep 19, 2016 by Marc Zyngier Committed by Thomas Gleixner Sep 19, 2016

genirq: Skip chained interrupt trigger setup if type is IRQ_TYPE_NONE

There is no point in trying to configure the trigger of a chained
interrupt if no trigger information has been configured. At best
this is ignored, and at the worse this confuses the underlying
irqchip (which is likely not to handle such a thing), and
unnecessarily alarms the user.

Only apply the configuration if type is not IRQ_TYPE_NONE.

Fixes: 1e12c4a9 ("genirq: Correctly configure the trigger on chained interrupts")
Reported-and-tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/CAMuHMdVW1eTn20=EtYcJ8hkVwohaSuH_yQXrY2MGBEvZ8fpFOg@mail.gmail.com
Link: http://lkml.kernel.org/r/1474274967-15984-1-git-send-email-marc.zyngier@arm.com

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

parent 3be79886

kernel/irq/chip.c

+6 −2

Original line number	Diff line number	Diff line
		@@ -820,6 +820,8 @@ __irq_do_set_handler(struct irq_desc *desc, irq_flow_handler_t handle,
		desc->name = name;

		if (handle != handle_bad_irq && is_chained) {
		unsigned int type = irqd_get_trigger_type(&desc->irq_data);

		/*
		* We're about to start this interrupt immediately,
		* hence the need to set the trigger configuration.
		@@ -828,8 +830,10 @@ __irq_do_set_handler(struct irq_desc *desc, irq_flow_handler_t handle,
		* chained interrupt. Reset it immediately because we
		* do know better.
		*/
		__irq_set_trigger(desc, irqd_get_trigger_type(&desc->irq_data));
		if (type != IRQ_TYPE_NONE) {
		__irq_set_trigger(desc, type);
		desc->handle_irq = handle;
		}

		irq_settings_set_noprobe(desc);
		irq_settings_set_norequest(desc);