1 files changed, 101 insertions, 50 deletions

diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c
index acb3f83b807..8c78443bca8 100644
--- a/drivers/base/power/runtime.c
+++ b/drivers/base/power/runtime.c
@@ -8,7 +8,9 @@
  */
 
 #include <linux/sched.h>
+#include <linux/export.h>
 #include <linux/pm_runtime.h>
+#include <trace/events/rpm.h>
 #include "power.h"
 
 static int rpm_resume(struct device *dev, int rpmflags);
@@ -28,13 +30,10 @@ static int rpm_suspend(struct device *dev, int rpmflags);
 void update_pm_runtime_accounting(struct device *dev)
 {
 	unsigned long now = jiffies;
-	int delta;
+	unsigned long delta;
 
 	delta = now - dev->power.accounting_timestamp;
 
-	if (delta < 0)
-		delta = 0;
-
 	dev->power.accounting_timestamp = now;
 
 	if (dev->power.disable_depth > 0)
@@ -155,6 +154,31 @@ static int rpm_check_suspend_allowed(struct device *dev)
 }
 
 /**
+ * __rpm_callback - Run a given runtime PM callback for a given device.
+ * @cb: Runtime PM callback to run.
+ * @dev: Device to run the callback for.
+ */
+static int __rpm_callback(int (*cb)(struct device *), struct device *dev)
+	__releases(&dev->power.lock) __acquires(&dev->power.lock)
+{
+	int retval;
+
+	if (dev->power.irq_safe)
+		spin_unlock(&dev->power.lock);
+	else
+		spin_unlock_irq(&dev->power.lock);
+
+	retval = cb(dev);
+
+	if (dev->power.irq_safe)
+		spin_lock(&dev->power.lock);
+	else
+		spin_lock_irq(&dev->power.lock);
+
+	return retval;
+}
+
+/**
  * rpm_idle - Notify device bus type if the device can be suspended.
  * @dev: Device to notify the bus type about.
  * @rpmflags: Flag bits.
@@ -171,6 +195,7 @@ static int rpm_idle(struct device *dev, int rpmflags)
 	int (*callback)(struct device *);
 	int retval;
 
+	trace_rpm_idle(dev, rpmflags);
 	retval = rpm_check_suspend_allowed(dev);
 	if (retval < 0)
 		;	/* Conditions are wrong. */
@@ -225,24 +250,14 @@ static int rpm_idle(struct device *dev, int rpmflags)
 	else
 		callback = NULL;
 
-	if (callback) {
-		if (dev->power.irq_safe)
-			spin_unlock(&dev->power.lock);
-		else
-			spin_unlock_irq(&dev->power.lock);
-
-		callback(dev);
-
-		if (dev->power.irq_safe)
-			spin_lock(&dev->power.lock);
-		else
-			spin_lock_irq(&dev->power.lock);
-	}
+	if (callback)
+		__rpm_callback(callback, dev);
 
 	dev->power.idle_notification = false;
 	wake_up_all(&dev->power.wait_queue);
 
  out:
+	trace_rpm_return_int(dev, _THIS_IP_, retval);
 	return retval;
 }
 
@@ -252,22 +267,14 @@ static int rpm_idle(struct device *dev, int rpmflags)
  * @dev: Device to run the callback for.
  */
 static int rpm_callback(int (*cb)(struct device *), struct device *dev)
-	__releases(&dev->power.lock) __acquires(&dev->power.lock)
 {
 	int retval;
 
 	if (!cb)
 		return -ENOSYS;
 
-	if (dev->power.irq_safe) {
-		retval = cb(dev);
-	} else {
-		spin_unlock_irq(&dev->power.lock);
+	retval = __rpm_callback(cb, dev);
 
-		retval = cb(dev);
-
-		spin_lock_irq(&dev->power.lock);
-	}
 	dev->power.runtime_error = retval;
 	return retval != -EACCES ? retval : -EIO;
 }
@@ -277,14 +284,19 @@ static int rpm_callback(int (*cb)(struct device *), struct device *dev)
  * @dev: Device to suspend.
  * @rpmflags: Flag bits.
  *
- * Check if the device's runtime PM status allows it to be suspended.  If
- * another suspend has been started earlier, either return immediately or wait
- * for it to finish, depending on the RPM_NOWAIT and RPM_ASYNC flags.  Cancel a
- * pending idle notification.  If the RPM_ASYNC flag is set then queue a
- * suspend request; otherwise run the ->runtime_suspend() callback directly.
- * If a deferred resume was requested while the callback was running then carry
- * it out; otherwise send an idle notification for the device (if the suspend
- * failed) or for its parent (if the suspend succeeded).
+ * Check if the device's runtime PM status allows it to be suspended.
+ * Cancel a pending idle notification, autosuspend or suspend. If
+ * another suspend has been started earlier, either return immediately
+ * or wait for it to finish, depending on the RPM_NOWAIT and RPM_ASYNC
+ * flags. If the RPM_ASYNC flag is set then queue a suspend request;
+ * otherwise run the ->runtime_suspend() callback directly. When
+ * ->runtime_suspend succeeded, if a deferred resume was requested while
+ * the callback was running then carry it out, otherwise send an idle
+ * notification for its parent (if the suspend succeeded and both
+ * ignore_children of parent->power and irq_safe of dev->power are not set).
+ * If ->runtime_suspend failed with -EAGAIN or -EBUSY, and if the RPM_AUTO
+ * flag is set and the next autosuspend-delay expiration time is in the
+ * future, schedule another autosuspend attempt.
  *
  * This function must be called under dev->power.lock with interrupts disabled.
  */
@@ -295,7 +307,7 @@ static int rpm_suspend(struct device *dev, int rpmflags)
 	struct device *parent = NULL;
 	int retval;
 
-	dev_dbg(dev, "%s flags 0x%x\n", __func__, rpmflags);
+	trace_rpm_suspend(dev, rpmflags);
 
  repeat:
 	retval = rpm_check_suspend_allowed(dev);
@@ -347,6 +359,15 @@ static int rpm_suspend(struct device *dev, int rpmflags)
 			goto out;
 		}
 
+		if (dev->power.irq_safe) {
+			spin_unlock(&dev->power.lock);
+
+			cpu_relax();
+
+			spin_lock(&dev->power.lock);
+			goto repeat;
+		}
+
 		/* Wait for the other suspend running in parallel with us. */
 		for (;;) {
 			prepare_to_wait(&dev->power.wait_queue, &wait,
@@ -396,19 +417,31 @@ static int rpm_suspend(struct device *dev, int rpmflags)
 	if (retval) {
 		__update_runtime_status(dev, RPM_ACTIVE);
 		dev->power.deferred_resume = false;
-		if (retval == -EAGAIN || retval == -EBUSY)
+		if (retval == -EAGAIN || retval == -EBUSY) {
 			dev->power.runtime_error = 0;
-		else
+
+			/*
+			 * If the callback routine failed an autosuspend, and
+			 * if the last_busy time has been updated so that there
+			 * is a new autosuspend expiration time, automatically
+			 * reschedule another autosuspend.
+			 */
+			if ((rpmflags & RPM_AUTO) &&
+			    pm_runtime_autosuspend_expiration(dev) != 0)
+				goto repeat;
+		} else {
 			pm_runtime_cancel_pending(dev);
-	} else {
+		}
+		wake_up_all(&dev->power.wait_queue);
+		goto out;
+	}
  no_callback:
-		__update_runtime_status(dev, RPM_SUSPENDED);
-		pm_runtime_deactivate_timer(dev);
+	__update_runtime_status(dev, RPM_SUSPENDED);
+	pm_runtime_deactivate_timer(dev);
 
-		if (dev->parent) {
-			parent = dev->parent;
-			atomic_add_unless(&parent->power.child_count, -1, 0);
-		}
+	if (dev->parent) {
+		parent = dev->parent;
+		atomic_add_unless(&parent->power.child_count, -1, 0);
 	}
 	wake_up_all(&dev->power.wait_queue);
 
@@ -430,7 +463,7 @@ static int rpm_suspend(struct device *dev, int rpmflags)
 	}
 
  out:
-	dev_dbg(dev, "%s returns %d\n", __func__, retval);
+	trace_rpm_return_int(dev, _THIS_IP_, retval);
 
 	return retval;
 }
@@ -459,7 +492,7 @@ static int rpm_resume(struct device *dev, int rpmflags)
 	struct device *parent = NULL;
 	int retval = 0;
 
-	dev_dbg(dev, "%s flags 0x%x\n", __func__, rpmflags);
+	trace_rpm_resume(dev, rpmflags);
 
  repeat:
 	if (dev->power.runtime_error)
@@ -496,6 +529,15 @@ static int rpm_resume(struct device *dev, int rpmflags)
 			goto out;
 		}
 
+		if (dev->power.irq_safe) {
+			spin_unlock(&dev->power.lock);
+
+			cpu_relax();
+
+			spin_lock(&dev->power.lock);
+			goto repeat;
+		}
+
 		/* Wait for the operation carried out in parallel with us. */
 		for (;;) {
 			prepare_to_wait(&dev->power.wait_queue, &wait,
@@ -615,7 +657,7 @@ static int rpm_resume(struct device *dev, int rpmflags)
 		spin_lock_irq(&dev->power.lock);
 	}
 
-	dev_dbg(dev, "%s returns %d\n", __func__, retval);
+	trace_rpm_return_int(dev, _THIS_IP_, retval);
 
 	return retval;
 }
@@ -732,13 +774,16 @@ EXPORT_SYMBOL_GPL(pm_schedule_suspend);
  * return immediately if it is larger than zero.  Then carry out an idle
  * notification, either synchronous or asynchronous.
  *
- * This routine may be called in atomic context if the RPM_ASYNC flag is set.
+ * This routine may be called in atomic context if the RPM_ASYNC flag is set,
+ * or if pm_runtime_irq_safe() has been called.
  */
 int __pm_runtime_idle(struct device *dev, int rpmflags)
 {
 	unsigned long flags;
 	int retval;
 
+	might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe);
+
 	if (rpmflags & RPM_GET_PUT) {
 		if (!atomic_dec_and_test(&dev->power.usage_count))
 			return 0;
@@ -761,13 +806,16 @@ EXPORT_SYMBOL_GPL(__pm_runtime_idle);
  * return immediately if it is larger than zero.  Then carry out a suspend,
  * either synchronous or asynchronous.
  *
- * This routine may be called in atomic context if the RPM_ASYNC flag is set.
+ * This routine may be called in atomic context if the RPM_ASYNC flag is set,
+ * or if pm_runtime_irq_safe() has been called.
  */
 int __pm_runtime_suspend(struct device *dev, int rpmflags)
 {
 	unsigned long flags;
 	int retval;
 
+	might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe);
+
 	if (rpmflags & RPM_GET_PUT) {
 		if (!atomic_dec_and_test(&dev->power.usage_count))
 			return 0;
@@ -789,13 +837,16 @@ EXPORT_SYMBOL_GPL(__pm_runtime_suspend);
  * If the RPM_GET_PUT flag is set, increment the device's usage count.  Then
  * carry out a resume, either synchronous or asynchronous.
  *
- * This routine may be called in atomic context if the RPM_ASYNC flag is set.
+ * This routine may be called in atomic context if the RPM_ASYNC flag is set,
+ * or if pm_runtime_irq_safe() has been called.
  */
 int __pm_runtime_resume(struct device *dev, int rpmflags)
 {
 	unsigned long flags;
 	int retval;
 
+	might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe);
+
 	if (rpmflags & RPM_GET_PUT)
 		atomic_inc(&dev->power.usage_count);