PM / Runtime: Reduce code duplication in core helper functions

Reduce code duplication in rpm_idle(), rpm_suspend() and rpm_resume()
by using local pointers to store callback addresses and moving some
duplicated code into a separate function.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Reviewed-by: Alan Stern <stern@rowland.harvard.edu>

1 files changed, 54 insertions, 68 deletions

diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c
index cd4e100a1362..e957c496a1b1 100644
--- a/drivers/base/power/runtime.c
+++ b/drivers/base/power/runtime.c
@@ -153,7 +153,6 @@ static int rpm_check_suspend_allowed(struct device *dev)
         return retval;
 }
 
-
 /**
  * rpm_idle - Notify device bus type if the device can be suspended.
  * @dev: Device to notify the bus type about.
@@ -167,8 +166,8 @@ static int rpm_check_suspend_allowed(struct device *dev)
  * This function must be called under dev->power.lock with interrupts disabled.
  */
 static int rpm_idle(struct device *dev, int rpmflags)
-        __releases(&dev->power.lock) __acquires(&dev->power.lock)
 {
+        int (*callback)(struct device *);
         int retval;
 
         retval = rpm_check_suspend_allowed(dev);
@@ -214,23 +213,19 @@ static int rpm_idle(struct device *dev, int rpmflags)
 
         dev->power.idle_notification = true;
 
-        if (dev->bus && dev->bus->pm && dev->bus->pm->runtime_idle) {
-                spin_unlock_irq(&dev->power.lock);
-
-                dev->bus->pm->runtime_idle(dev);
-
-                spin_lock_irq(&dev->power.lock);
-        } else if (dev->type && dev->type->pm && dev->type->pm->runtime_idle) {
-                spin_unlock_irq(&dev->power.lock);
-
-                dev->type->pm->runtime_idle(dev);
+        if (dev->bus && dev->bus->pm && dev->bus->pm->runtime_idle)
+                callback = dev->bus->pm->runtime_idle;
+        else if (dev->type && dev->type->pm && dev->type->pm->runtime_idle)
+                callback = dev->type->pm->runtime_idle;
+        else if (dev->class && dev->class->pm)
+                callback = dev->class->pm->runtime_idle;
+        else
+                callback = NULL;
 
-                spin_lock_irq(&dev->power.lock);
-        } else if (dev->class && dev->class->pm
-            && dev->class->pm->runtime_idle) {
+        if (callback) {
                 spin_unlock_irq(&dev->power.lock);
 
-                dev->class->pm->runtime_idle(dev);
+                callback(dev);
 
                 spin_lock_irq(&dev->power.lock);
         }
@@ -243,6 +238,29 @@ static int rpm_idle(struct device *dev, int rpmflags)
 }
 
 /**
+ * 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 (!cb)
+                return -ENOSYS;
+
+        spin_unlock_irq(&dev->power.lock);
+
+        retval = cb(dev);
+
+        spin_lock_irq(&dev->power.lock);
+        dev->power.runtime_error = retval;
+
+        return retval;
+}
+
+/**
  * rpm_suspend - Carry out run-time suspend of given device.
  * @dev: Device to suspend.
  * @rpmflags: Flag bits.
@@ -261,6 +279,7 @@ static int rpm_idle(struct device *dev, int rpmflags)
 static int rpm_suspend(struct device *dev, int rpmflags)
         __releases(&dev->power.lock) __acquires(&dev->power.lock)
 {
+        int (*callback)(struct device *);
         struct device *parent = NULL;
         bool notify = false;
         int retval;
@@ -351,33 +370,16 @@ static int rpm_suspend(struct device *dev, int rpmflags)
 
         __update_runtime_status(dev, RPM_SUSPENDING);
 
-        if (dev->bus && dev->bus->pm && dev->bus->pm->runtime_suspend) {
-                spin_unlock_irq(&dev->power.lock);
-
-                retval = dev->bus->pm->runtime_suspend(dev);
-
-                spin_lock_irq(&dev->power.lock);
-                dev->power.runtime_error = retval;
-        } else if (dev->type && dev->type->pm
-            && dev->type->pm->runtime_suspend) {
-                spin_unlock_irq(&dev->power.lock);
-
-                retval = dev->type->pm->runtime_suspend(dev);
-
-                spin_lock_irq(&dev->power.lock);
-                dev->power.runtime_error = retval;
-        } else if (dev->class && dev->class->pm
-            && dev->class->pm->runtime_suspend) {
-                spin_unlock_irq(&dev->power.lock);
-
-                retval = dev->class->pm->runtime_suspend(dev);
-
-                spin_lock_irq(&dev->power.lock);
-                dev->power.runtime_error = retval;
-        } else {
-                retval = -ENOSYS;
-        }
+        if (dev->bus && dev->bus->pm && dev->bus->pm->runtime_suspend)
+                callback = dev->bus->pm->runtime_suspend;
+        else if (dev->type && dev->type->pm && dev->type->pm->runtime_suspend)
+                callback = dev->type->pm->runtime_suspend;
+        else if (dev->class && dev->class->pm)
+                callback = dev->class->pm->runtime_suspend;
+        else
+                callback = NULL;
 
+        retval = rpm_callback(callback, dev);
         if (retval) {
                 __update_runtime_status(dev, RPM_ACTIVE);
                 dev->power.deferred_resume = 0;
@@ -443,6 +445,7 @@ static int rpm_suspend(struct device *dev, int rpmflags)
 static int rpm_resume(struct device *dev, int rpmflags)
         __releases(&dev->power.lock) __acquires(&dev->power.lock)
 {
+        int (*callback)(struct device *);
         struct device *parent = NULL;
         int retval = 0;
 
@@ -563,33 +566,16 @@ static int rpm_resume(struct device *dev, int rpmflags)
 
         __update_runtime_status(dev, RPM_RESUMING);
 
-        if (dev->bus && dev->bus->pm && dev->bus->pm->runtime_resume) {
-                spin_unlock_irq(&dev->power.lock);
-
-                retval = dev->bus->pm->runtime_resume(dev);
-
-                spin_lock_irq(&dev->power.lock);
-                dev->power.runtime_error = retval;
-        } else if (dev->type && dev->type->pm
-            && dev->type->pm->runtime_resume) {
-                spin_unlock_irq(&dev->power.lock);
-
-                retval = dev->type->pm->runtime_resume(dev);
-
-                spin_lock_irq(&dev->power.lock);
-                dev->power.runtime_error = retval;
-        } else if (dev->class && dev->class->pm
-            && dev->class->pm->runtime_resume) {
-                spin_unlock_irq(&dev->power.lock);
-
-                retval = dev->class->pm->runtime_resume(dev);
-
-                spin_lock_irq(&dev->power.lock);
-                dev->power.runtime_error = retval;
-        } else {
-                retval = -ENOSYS;
-        }
+        if (dev->bus && dev->bus->pm && dev->bus->pm->runtime_resume)
+                callback = dev->bus->pm->runtime_resume;
+        else if (dev->type && dev->type->pm && dev->type->pm->runtime_resume)
+                callback = dev->type->pm->runtime_resume;
+        else if (dev->class && dev->class->pm)
+                callback = dev->class->pm->runtime_resume;
+        else
+                callback = NULL;
 
+        retval = rpm_callback(callback, dev);
         if (retval) {
                 __update_runtime_status(dev, RPM_SUSPENDED);
                 pm_runtime_cancel_pending(dev);