This is a note to let you know that I've just added the patch titled
PM / wakeirq: Fix dedicated wakeirq for drivers not using autosuspend
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
pm-wakeirq-fix-dedicated-wakeirq-for-drivers-not-using-autosuspend.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From bed570307ed78f21b77cb04a1df781dee4a8f05a Mon Sep 17 00:00:00 2001
From: Tony Lindgren <tony@xxxxxxxxxxx>
Date: Mon, 5 Dec 2016 16:38:16 -0800
Subject: PM / wakeirq: Fix dedicated wakeirq for drivers not using autosuspend
From: Tony Lindgren <tony@xxxxxxxxxxx>
commit bed570307ed78f21b77cb04a1df781dee4a8f05a upstream.
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@xxxxxxxxxxx>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/base/power/power.h | 19 ++++++++++
drivers/base/power/runtime.c | 8 ++--
drivers/base/power/wakeirq.c | 76 +++++++++++++++++++++++++++++++++++++------
3 files changed, 88 insertions(+), 15 deletions(-)
--- a/drivers/base/power/power.h
+++ b/drivers/base/power/power.h
@@ -21,14 +21,22 @@ extern void pm_runtime_init(struct devic
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_ir
{
}
+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
--- a/drivers/base/power/runtime.c
+++ b/drivers/base/power/runtime.c
@@ -515,7 +515,7 @@ static int rpm_suspend(struct device *de
callback = RPM_GET_CALLBACK(dev, runtime_suspend);
- dev_pm_enable_wake_irq(dev);
+ dev_pm_enable_wake_irq_check(dev, true);
retval = rpm_callback(callback, dev);
if (retval)
goto fail;
@@ -554,7 +554,7 @@ static int rpm_suspend(struct device *de
return retval;
fail:
- dev_pm_disable_wake_irq(dev);
+ dev_pm_disable_wake_irq_check(dev);
__update_runtime_status(dev, RPM_ACTIVE);
dev->power.deferred_resume = false;
wake_up_all(&dev->power.wait_queue);
@@ -737,12 +737,12 @@ static int rpm_resume(struct device *dev
callback = RPM_GET_CALLBACK(dev, runtime_resume);
- dev_pm_disable_wake_irq(dev);
+ dev_pm_disable_wake_irq_check(dev);
retval = rpm_callback(callback, dev);
if (retval) {
__update_runtime_status(dev, RPM_SUSPENDED);
pm_runtime_cancel_pending(dev);
- dev_pm_enable_wake_irq(dev);
+ dev_pm_enable_wake_irq_check(dev, false);
} else {
no_callback:
__update_runtime_status(dev, RPM_ACTIVE);
--- a/drivers/base/power/wakeirq.c
+++ b/drivers/base/power/wakeirq.c
@@ -110,8 +110,10 @@ void dev_pm_clear_wake_irq(struct device
dev->power.wakeirq = NULL;
spin_unlock_irqrestore(&dev->power.lock, flags);
- if (wirq->dedicated_irq)
+ if (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED) {
free_irq(wirq->irq, wirq);
+ wirq->status &= ~WAKE_IRQ_DEDICATED_MASK;
+ }
kfree(wirq);
}
EXPORT_SYMBOL_GPL(dev_pm_clear_wake_irq);
@@ -179,7 +181,6 @@ int dev_pm_set_dedicated_wake_irq(struct
wirq->dev = dev;
wirq->irq = irq;
- wirq->dedicated_irq = true;
irq_set_status_flags(irq, IRQ_NOAUTOEN);
/*
@@ -195,6 +196,8 @@ int dev_pm_set_dedicated_wake_irq(struct
if (err)
goto err_free_irq;
+ wirq->status = WAKE_IRQ_DEDICATED_ALLOCATED;
+
return err;
err_free_irq:
@@ -210,9 +213,9 @@ EXPORT_SYMBOL_GPL(dev_pm_set_dedicated_w
* dev_pm_enable_wake_irq - Enable device wake-up interrupt
* @dev: Device
*
- * Called from the bus code or the device driver for
- * runtime_suspend() to enable the wake-up interrupt while
- * the device is running.
+ * Optionally called from the bus code or the device driver for
+ * runtime_resume() to override the PM runtime core managed wake-up
+ * interrupt handling to enable the wake-up interrupt.
*
* Note that for runtime_suspend()) the wake-up interrupts
* should be unconditionally enabled unlike for suspend()
@@ -222,7 +225,7 @@ void dev_pm_enable_wake_irq(struct devic
{
struct wake_irq *wirq = dev->power.wakeirq;
- if (wirq && wirq->dedicated_irq)
+ if (wirq && (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED))
enable_irq(wirq->irq);
}
EXPORT_SYMBOL_GPL(dev_pm_enable_wake_irq);
@@ -231,20 +234,73 @@ EXPORT_SYMBOL_GPL(dev_pm_enable_wake_irq
* dev_pm_disable_wake_irq - Disable device wake-up interrupt
* @dev: Device
*
- * Called from the bus code or the device driver for
- * runtime_resume() to disable the wake-up interrupt while
- * the device is running.
+ * Optionally called from the bus code or the device driver for
+ * runtime_suspend() to override the PM runtime core managed wake-up
+ * interrupt handling to disable the wake-up interrupt.
*/
void dev_pm_disable_wake_irq(struct device *dev)
{
struct wake_irq *wirq = dev->power.wakeirq;
- if (wirq && wirq->dedicated_irq)
+ if (wirq && (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED))
disable_irq_nosync(wirq->irq);
}
EXPORT_SYMBOL_GPL(dev_pm_disable_wake_irq);
/**
+ * dev_pm_enable_wake_irq_check - Checks and enables wake-up interrupt
+ * @dev: Device
+ * @can_change_status: Can change wake-up interrupt status
+ *
+ * Enables wakeirq conditionally. We need to enable wake-up interrupt
+ * lazily on the first rpm_suspend(). This is needed as the consumer device
+ * starts in RPM_SUSPENDED state, and the the first pm_runtime_get() would
+ * otherwise try to disable already disabled wakeirq. The wake-up interrupt
+ * starts disabled with IRQ_NOAUTOEN set.
+ *
+ * Should be only called from rpm_suspend() and rpm_resume() path.
+ * Caller must hold &dev->power.lock to change wirq->status
+ */
+void dev_pm_enable_wake_irq_check(struct device *dev,
+ bool can_change_status)
+{
+ struct wake_irq *wirq = dev->power.wakeirq;
+
+ if (!wirq || !((wirq->status & WAKE_IRQ_DEDICATED_MASK)))
+ return;
+
+ if (likely(wirq->status & WAKE_IRQ_DEDICATED_MANAGED)) {
+ goto enable;
+ } else if (can_change_status) {
+ wirq->status |= WAKE_IRQ_DEDICATED_MANAGED;
+ goto enable;
+ }
+
+ return;
+
+enable:
+ enable_irq(wirq->irq);
+}
+
+/**
+ * dev_pm_disable_wake_irq_check - Checks and disables wake-up interrupt
+ * @dev: Device
+ *
+ * Disables wake-up interrupt conditionally based on status.
+ * Should be only called from rpm_suspend() and rpm_resume() path.
+ */
+void dev_pm_disable_wake_irq_check(struct device *dev)
+{
+ struct wake_irq *wirq = dev->power.wakeirq;
+
+ if (!wirq || !((wirq->status & WAKE_IRQ_DEDICATED_MASK)))
+ return;
+
+ if (wirq->status & WAKE_IRQ_DEDICATED_MANAGED)
+ disable_irq_nosync(wirq->irq);
+}
+
+/**
* dev_pm_arm_wake_irq - Arm device wake-up
* @wirq: Device wake-up interrupt
*
Patches currently in stable-queue which might be from tony@xxxxxxxxxxx are
queue-4.9/pm-wakeirq-fix-dedicated-wakeirq-for-drivers-not-using-autosuspend.patch
queue-4.9/usb-musb-fix-trying-to-free-already-free-irq-4.patch
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