PM / wakeirq: Fix dedicated wakeirq for drivers not using autosuspend

I noticed some wakeirq flakeyness with consumer drivers not using
autosuspend. For drivers not using autosuspend, the wakeirq may never
get unmasked in rpm_suspend() because of irq desc->depth.

We are configuring dedicated wakeirqs to start with IRQ_NOAUTOEN as we
naturally don't want them running until rpm_suspend() is called.

However, when a consumer driver initially calls pm_runtime_get(), we
now wrongly start with disable_irq_nosync() call on the dedicated
wakeirq that is disabled to start with.

This causes desc->depth to toggle between 1 and 2 instead of the usual
0 and 1. This can prevent enable_irq() from unmasking the wakeirq as
that only happens at desc->depth 1.

This does not necessarily show up with drivers using autosuspend as
there is time for disable_irq_nosync() before rpm_suspend() gets called
after the autosuspend timeout.

Let's fix the issue by adding wirq->status that lazily gets set on
the first rpm_suspend(). We also need PM runtime core private functions
for dev_pm_enable_wake_irq_check() and dev_pm_disable_wake_irq_check()
so we can enable the dedicated wakeirq on the first rpm_suspend().

While at it, let's also fix the comments for dev_pm_enable_wake_irq()
and dev_pm_disable_wake_irq(). Those can still be used by the consumer
drivers as needed because the IRQ core manages the interrupt usecount
for us.

Fixes: 4990d4fe327b (PM / Wakeirq: Add automated device wake IRQ handling)
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 18 insertions, 1 deletions

diff --git a/drivers/base/power/power.h b/drivers/base/power/power.h
index 50e30e7b059d..a84332aefc2d 100644
--- a/drivers/base/power/power.h
+++ b/drivers/base/power/power.h
@@ -21,14 +21,22 @@ extern void pm_runtime_init(struct device *dev);
 extern void pm_runtime_reinit(struct device *dev);
 extern void pm_runtime_remove(struct device *dev);
 
+#define WAKE_IRQ_DEDICATED_ALLOCATED	BIT(0)
+#define WAKE_IRQ_DEDICATED_MANAGED	BIT(1)
+#define WAKE_IRQ_DEDICATED_MASK		(WAKE_IRQ_DEDICATED_ALLOCATED | \
+					 WAKE_IRQ_DEDICATED_MANAGED)
+
 struct wake_irq {
 	struct device *dev;
+	unsigned int status;
 	int irq;
-	bool dedicated_irq:1;
 };
 
 extern void dev_pm_arm_wake_irq(struct wake_irq *wirq);
 extern void dev_pm_disarm_wake_irq(struct wake_irq *wirq);
+extern void dev_pm_enable_wake_irq_check(struct device *dev,
+					 bool can_change_status);
+extern void dev_pm_disable_wake_irq_check(struct device *dev);
 
 #ifdef CONFIG_PM_SLEEP
 
@@ -104,6 +112,15 @@ static inline void dev_pm_disarm_wake_irq(struct wake_irq *wirq)
 {
 }
 
+static inline void dev_pm_enable_wake_irq_check(struct device *dev,
+						bool can_change_status)
+{
+}
+
+static inline void dev_pm_disable_wake_irq_check(struct device *dev)
+{
+}
+
 #endif
 
 #ifdef CONFIG_PM_SLEEP