linux-kernel - [tip:irq/core] PM / sleep / irq: Do not suspend wakeup interrupts

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Date:	Tue, 15 Jul 2014 04:01:10 -0700
From:	"tip-bot for Rafael J. Wysocki" <tipbot@...or.com>
To:	linux-tip-commits@...r.kernel.org
Cc:	linux-kernel@...r.kernel.org, hpa@...or.com, mingo@...nel.org,
	rafael.j.wysocki@...el.com, aubrey.li@...ux.intel.com,
	gnomes@...rguk.ukuu.org.uk, dmitry.torokhov@...il.com,
	tglx@...utronix.de
Subject: [tip:irq/core] PM / sleep / irq: Do not suspend wakeup interrupts

Commit-ID:  d709f7bcbb3ab01704fa7b37a2e4b981cf3783c1
Gitweb:     http://git.kernel.org/tip/d709f7bcbb3ab01704fa7b37a2e4b981cf3783c1
Author:     Rafael J. Wysocki <rafael.j.wysocki@...el.com>
AuthorDate: Thu, 10 Jul 2014 23:37:54 +0200
Committer:  Thomas Gleixner <tglx@...utronix.de>
CommitDate: Tue, 15 Jul 2014 12:57:26 +0200

PM / sleep / irq: Do not suspend wakeup interrupts

If an IRQ has been configured for wakeup via enable_irq_wake(), the
driver who has done that must be prepared for receiving interrupts
after suspend_device_irqs() has returned, so there is no need to
"suspend" such IRQs.  Moreover, if drivers using enable_irq_wake()
actually want to receive interrupts after suspend_device_irqs() has
returned, they need to add IRQF_NO_SUSPEND to the IRQ flags while
requesting the IRQs, which shouldn't be necessary (it also goes a bit
too far, as IRQF_NO_SUSPEND causes the IRQ to be ignored by
suspend_device_irqs() all the time regardless of whether or not it
has been configured for signaling wakeup).

For the above reasons, make __disable_irq() ignore IRQ descriptors
with IRQD_WAKEUP_STATE set when its suspend argument is true which
effectively causes them to behave like IRQs with IRQF_NO_SUSPEND
set.

This also allows IRQs configured for wakeup via enable_irq_wake()
to work as wakeup interrupts for the "freeze" (suspend-to-idle)
sleep mode automatically just like for any other sleep states.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@...el.com>
Cc: Li Aubrey <aubrey.li@...ux.intel.com>
Cc: Dmitry Torokhov <dmitry.torokhov@...il.com>
Cc: One Thousand Gnomes <gnomes@...rguk.ukuu.org.uk>
Link: http://lkml.kernel.org/r/4679574.kGUnqAuNl9@vostro.rjw.lan
Signed-off-by: Thomas Gleixner <tglx@...utronix.de>
---
 kernel/irq/manage.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 3dc6a61..88657d7 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -385,7 +385,8 @@ setup_affinity(unsigned int irq, struct irq_desc *desc, struct cpumask *mask)
 void __disable_irq(struct irq_desc *desc, unsigned int irq, bool suspend)
 {
 	if (suspend) {
-		if (!desc->action || (desc->action->flags & IRQF_NO_SUSPEND))
+		if (!desc->action || (desc->action->flags & IRQF_NO_SUSPEND) ||
+		    irqd_has_set(&desc->irq_data, IRQD_WAKEUP_STATE))
 			return;
 		desc->istate |= IRQS_SUSPENDED;
 	}
--
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