More power management updates for 6.19-rc1

Fix a runtime PM unit test added during the 6.18 development cycle and
 change the pm_runtime_barrier() return type to void (Brian Norris).
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Merge tag 'pm-6.19-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull more power management updates from Rafael Wysocki:
 "Fix a runtime PM unit test added during the 6.18 development cycle and
  change the pm_runtime_barrier() return type to void (Brian Norris)"

* tag 'pm-6.19-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  coccinelle: Drop pm_runtime_barrier() error code checks
  PM: runtime: Make pm_runtime_barrier() return void
  PM: runtime: Stop checking pm_runtime_barrier() return code

Documentation/power/runtime_pm.rst

@@ -443,13 +443,11 @@ drivers/base/power/runtime.c and include/linux/pm_runtime.h:
       necessary to execute the subsystem-level resume callback for the device
       to satisfy that request, otherwise 0 is returned
 
-  `int pm_runtime_barrier(struct device *dev);`
+  `void pm_runtime_barrier(struct device *dev);`
     - check if there's a resume request pending for the device and resume it
       (synchronously) in that case, cancel any other pending runtime PM requests
       regarding it and wait for all runtime PM operations on it in progress to
-      complete; returns 1 if there was a resume request pending and it was
+      complete
-      necessary to execute the subsystem-level resume callback for the device to
-      satisfy that request, otherwise 0 is returned
 
   `void pm_suspend_ignore_children(struct device *dev, bool enable);`
     - set/unset the power.ignore_children flag of the device

drivers/base/power/runtime-test.c

@@ -37,10 +37,6 @@ static void pm_runtime_already_suspended_test(struct kunit *test)
 	pm_runtime_enable(dev);
 	KUNIT_EXPECT_TRUE(test, pm_runtime_suspended(dev));
 
-	pm_runtime_get_noresume(dev);
-	KUNIT_EXPECT_EQ(test, 0, pm_runtime_barrier(dev)); /* no wakeup needed */
-	pm_runtime_put(dev);
-
 	pm_runtime_get_noresume(dev);
 	KUNIT_EXPECT_EQ(test, 1, pm_runtime_put_sync(dev));
 
@@ -174,7 +170,7 @@ static void pm_runtime_error_test(struct kunit *test)
 	KUNIT_EXPECT_TRUE(test, pm_runtime_suspended(dev));
 
 	KUNIT_EXPECT_EQ(test, 0, pm_runtime_get(dev));
-	KUNIT_EXPECT_EQ(test, 1, pm_runtime_barrier(dev)); /* resume was pending */
+	pm_runtime_barrier(dev);
 	pm_runtime_put(dev);
 	pm_runtime_suspend(dev); /* flush the put(), to suspend */
 	KUNIT_EXPECT_TRUE(test, pm_runtime_suspended(dev));
@@ -225,7 +221,7 @@ static void pm_runtime_probe_active_test(struct kunit *test)
 	KUNIT_EXPECT_TRUE(test, pm_runtime_active(dev));
 
 	/* Nothing to flush. We stay active. */
-	KUNIT_EXPECT_EQ(test, 0, pm_runtime_barrier(dev));
+	pm_runtime_barrier(dev);
 	KUNIT_EXPECT_TRUE(test, pm_runtime_active(dev));
 
 	/* Ask for idle? Now we suspend. */

drivers/base/power/runtime.c

@@ -1467,30 +1467,20 @@ static void __pm_runtime_barrier(struct device *dev)
  * Next, make sure that all pending requests for the device have been flushed
  * from pm_wq and wait for all runtime PM operations involving the device in
  * progress to complete.
- *
- * Return value:
- * 1, if there was a resume request pending and the device had to be woken up,
- * 0, otherwise
  */
-int pm_runtime_barrier(struct device *dev)
+void pm_runtime_barrier(struct device *dev)
 {
-	int retval = 0;
-
 	pm_runtime_get_noresume(dev);
 	spin_lock_irq(&dev->power.lock);
 
 	if (dev->power.request_pending
-	    && dev->power.request == RPM_REQ_RESUME) {
+	    && dev->power.request == RPM_REQ_RESUME)
 		rpm_resume(dev, 0);
-		retval = 1;
-	}
 
 	__pm_runtime_barrier(dev);
 
 	spin_unlock_irq(&dev->power.lock);
 	pm_runtime_put_noidle(dev);
-
-	return retval;
 }
 EXPORT_SYMBOL_GPL(pm_runtime_barrier);
 

include/linux/pm_runtime.h

@@ -76,7 +76,7 @@ extern int pm_runtime_get_if_active(struct device *dev);
 extern int pm_runtime_get_if_in_use(struct device *dev);
 extern int pm_schedule_suspend(struct device *dev, unsigned int delay);
 extern int __pm_runtime_set_status(struct device *dev, unsigned int status);
-extern int pm_runtime_barrier(struct device *dev);
+extern void pm_runtime_barrier(struct device *dev);
 extern bool pm_runtime_block_if_disabled(struct device *dev);
 extern void pm_runtime_unblock(struct device *dev);
 extern void pm_runtime_enable(struct device *dev);
@@ -284,7 +284,7 @@ static inline int pm_runtime_get_if_active(struct device *dev)
 }
 static inline int __pm_runtime_set_status(struct device *dev,
 					    unsigned int status) { return 0; }
-static inline int pm_runtime_barrier(struct device *dev) { return 0; }
+static inline void pm_runtime_barrier(struct device *dev) {}
 static inline bool pm_runtime_block_if_disabled(struct device *dev) { return true; }
 static inline void pm_runtime_unblock(struct device *dev) {}
 static inline void pm_runtime_enable(struct device *dev) {}

scripts/coccinelle/api/pm_runtime.cocci

@@ -37,7 +37,6 @@ ret@p = \(pm_runtime_idle\|
 	pm_runtime_put_sync_autosuspend\|
 	pm_runtime_set_active\|
 	pm_schedule_suspend\|
-	pm_runtime_barrier\|
 	pm_generic_runtime_suspend\|
 	pm_generic_runtime_resume\)(...);
 ...