USB: convert to the runtime PM framework

This patch (as1329) converts the USB stack over to the PM core's
runtime PM framework. This involves numerous changes throughout
usbcore, especially to hub.c and driver.c. Perhaps the most notable
change is that CONFIG_USB_SUSPEND now depends on CONFIG_PM_RUNTIME
instead of CONFIG_PM.

Several fields in the usb_device and usb_interface structures are no
longer needed. Some code which used to depend on CONFIG_USB_PM now
depends on CONFIG_USB_SUSPEND (requiring some rearrangement of header
files).

The only visible change in behavior should be that following a system
sleep (resume from RAM or resume from hibernation), autosuspended USB
devices will be resumed just like everything else. They won't remain
suspended. But if they aren't in use then they will naturally
autosuspend again in a few seconds.

Signed-off-by: Alan Stern <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

Documentation/usb/power-management.txt

···
 
 		 Alan Stern <[e-mail]>
 
-			    November 10, 2009
+			    December 11, 2009
 
 
 
···
 information about system PM).
 
 Note: Dynamic PM support for USB is present only if the kernel was
-built with CONFIG_USB_SUSPEND enabled.  System PM support is present
-only if the kernel was built with CONFIG_SUSPEND or CONFIG_HIBERNATION
-enabled.
+built with CONFIG_USB_SUSPEND enabled (which depends on
+CONFIG_PM_RUNTIME).  System PM support is present only if the kernel
+was built with CONFIG_SUSPEND or CONFIG_HIBERNATION enabled.
 
 
 	What is Remote Wakeup?
···
 	void usb_autopm_get_interface_no_resume(struct usb_interface *intf);
 	void usb_autopm_put_interface_no_suspend(struct usb_interface *intf);
 
-The functions work by maintaining a counter in the usb_interface
-structure.  When intf->pm_usage_count is > 0 then the interface is
-deemed to be busy, and the kernel will not autosuspend the interface's
-device.  When intf->pm_usage_count is <= 0 then the interface is
-considered to be idle, and the kernel may autosuspend the device.
+The functions work by maintaining a usage counter in the
+usb_interface's embedded device structure.  When the counter is > 0
+then the interface is deemed to be busy, and the kernel will not
+autosuspend the interface's device.  When the usage counter is = 0
+then the interface is considered to be idle, and the kernel may
+autosuspend the device.
 
-(There is a similar pm_usage_count field in struct usb_device,
+(There is a similar usage counter field in struct usb_device,
 associated with the device itself rather than any of its interfaces.
-This field is used only by the USB core.)
+This counter is used only by the USB core.)
 
-Drivers must not modify intf->pm_usage_count directly; its value
-should be changed only be using the functions listed above.  Drivers
-are responsible for insuring that the overall change to pm_usage_count
-during their lifetime balances out to 0 (it may be necessary for the
-disconnect method to call usb_autopm_put_interface() one or more times
-to fulfill this requirement).  The first two routines use the PM mutex
-in struct usb_device for mutual exclusion; drivers using the async
-routines are responsible for their own synchronization and mutual
-exclusion.
+Drivers need not be concerned about balancing changes to the usage
+counter; the USB core will undo any remaining "get"s when a driver
+is unbound from its interface.  As a corollary, drivers must not call
+any of the usb_autopm_* functions after their diconnect() routine has
+returned.
 
-	usb_autopm_get_interface() increments pm_usage_count and
-	attempts an autoresume if the new value is > 0 and the
-	device is suspended.
+Drivers using the async routines are responsible for their own
+synchronization and mutual exclusion.
 
-	usb_autopm_put_interface() decrements pm_usage_count and
-	attempts an autosuspend if the new value is <= 0 and the
-	device isn't suspended.
+	usb_autopm_get_interface() increments the usage counter and
+	does an autoresume if the device is suspended.  If the
+	autoresume fails, the counter is decremented back.
+
+	usb_autopm_put_interface() decrements the usage counter and
+	attempts an autosuspend if the new value is = 0.
 
 	usb_autopm_get_interface_async() and
 	usb_autopm_put_interface_async() do almost the same things as
-	their non-async counterparts.  The differences are: they do
-	not acquire the PM mutex, and they use a workqueue to do their
+	their non-async counterparts.  The big difference is that they
+	use a workqueue to do the resume or suspend part of their
 	jobs.  As a result they can be called in an atomic context,
 	such as an URB's completion handler, but when they return the
-	device will not generally not yet be in the desired state.
+	device will generally not yet be in the desired state.
 
 	usb_autopm_get_interface_no_resume() and
 	usb_autopm_put_interface_no_suspend() merely increment or
-	decrement the pm_usage_count value; they do not attempt to
-	carry out an autoresume or an autosuspend.  Hence they can be
-	called in an atomic context.
+	decrement the usage counter; they do not attempt to carry out
+	an autoresume or an autosuspend.  Hence they can be called in
+	an atomic context.
 
-The conventional usage pattern is that a driver calls
+The simplest usage pattern is that a driver calls
 usb_autopm_get_interface() in its open routine and
-usb_autopm_put_interface() in its close or release routine.  But
-other patterns are possible.
+usb_autopm_put_interface() in its close or release routine.  But other
+patterns are possible.
 
 The autosuspend attempts mentioned above will often fail for one
 reason or another.  For example, the power/level attribute might be
 set to "on", or another interface in the same device might not be
 idle.  This is perfectly normal.  If the reason for failure was that
-the device hasn't been idle for long enough, a delayed workqueue
-routine is automatically set up to carry out the operation when the
-autosuspend idle-delay has expired.
+the device hasn't been idle for long enough, a timer is scheduled to
+carry out the operation automatically when the autosuspend idle-delay
+has expired.
 
 Autoresume attempts also can fail, although failure would mean that
 the device is no longer present or operating properly.  Unlike
-autosuspend, there's no delay for an autoresume.
+autosuspend, there's no idle-delay for an autoresume.
 
 
 	Other parts of the driver interface
···
 Normally a driver would set this flag in its probe method, at which
 time the device is guaranteed not to be autosuspended.)
 
-The synchronous usb_autopm_* routines have to run in a sleepable
-process context; they must not be called from an interrupt handler or
-while holding a spinlock.  In fact, the entire autosuspend mechanism
-is not well geared toward interrupt-driven operation.  However there
-is one thing a driver can do in an interrupt handler:
+If a driver does its I/O asynchronously in interrupt context, it
+should call usb_autopm_get_interface_async() before starting output and
+usb_autopm_put_interface_async() when the output queue drains.  When
+it receives an input event, it should call
 
 	usb_mark_last_busy(struct usb_device *udev);
 
-This sets udev->last_busy to the current time.  udev->last_busy is the
-field used for idle-delay calculations; updating it will cause any
-pending autosuspend to be moved back.  The usb_autopm_* routines will
-also set the last_busy field to the current time.
+in the event handler.  This sets udev->last_busy to the current time.
+udev->last_busy is the field used for idle-delay calculations;
+updating it will cause any pending autosuspend to be moved back.  Most
+of the usb_autopm_* routines will also set the last_busy field to the
+current time.
 
-Calling urb_mark_last_busy() from within an URB completion handler is
-subject to races: The kernel may have just finished deciding the
-device has been idle for long enough but not yet gotten around to
-calling the driver's suspend method.  The driver would have to be
-responsible for synchronizing its suspend method with its URB
-completion handler and causing the autosuspend to fail with -EBUSY if
-an URB had completed too recently.
+Asynchronous operation is always subject to races.  For example, a
+driver may call one of the usb_autopm_*_interface_async() routines at
+a time when the core has just finished deciding the device has been
+idle for long enough but not yet gotten around to calling the driver's
+suspend method.  The suspend method must be responsible for
+synchronizing with the output request routine and the URB completion
+handler; it should cause autosuspends to fail with -EBUSY if the
+driver needs to use the device.
 
 External suspend calls should never be allowed to fail in this way,
 only autosuspend calls.  The driver can tell them apart by checking
···
 method; this bit will be set for internal PM events (autosuspend) and
 clear for external PM events.
 
-Many of the ingredients in the autosuspend framework are oriented
-towards interfaces: The usb_interface structure contains the
-pm_usage_cnt field, and the usb_autopm_* routines take an interface
-pointer as their argument.  But somewhat confusingly, a few of the
-pieces (i.e., usb_mark_last_busy()) use the usb_device structure
-instead.  Drivers need to keep this straight; they can call
-interface_to_usbdev() to find the device structure for a given
-interface.
 
+	Mutual exclusion
+	----------------
 
-	Locking requirements
-	--------------------
-
-All three suspend/resume methods are always called while holding the
-usb_device's PM mutex.  For external events -- but not necessarily for
-autosuspend or autoresume -- the device semaphore (udev->dev.sem) will
-also be held.  This implies that external suspend/resume events are
-mutually exclusive with calls to probe, disconnect, pre_reset, and
-post_reset; the USB core guarantees that this is true of internal
-suspend/resume events as well.
+For external events -- but not necessarily for autosuspend or
+autoresume -- the device semaphore (udev->dev.sem) will be held when a
+suspend or resume method is called.  This implies that external
+suspend/resume events are mutually exclusive with calls to probe,
+disconnect, pre_reset, and post_reset; the USB core guarantees that
+this is true of autosuspend/autoresume events as well.
 
 If a driver wants to block all suspend/resume calls during some
-critical section, it can simply acquire udev->pm_mutex. Note that
-calls to resume may be triggered indirectly. Block IO due to memory
-allocations can make the vm subsystem resume a device. Thus while
-holding this lock you must not allocate memory with GFP_KERNEL or
-GFP_NOFS.
-
-Alternatively, if the critical section might call some of the
-usb_autopm_* routines, the driver can avoid deadlock by doing:
-
-	down(&udev->dev.sem);
-	rc = usb_autopm_get_interface(intf);
-
-and at the end of the critical section:
-
-	if (!rc)
-		usb_autopm_put_interface(intf);
-	up(&udev->dev.sem);
-
-Holding the device semaphore will block all external PM calls, and the
-usb_autopm_get_interface() will prevent any internal PM calls, even if
-it fails.  (Exercise: Why?)
-
-The rules for locking order are:
-
-	Never acquire any device semaphore while holding any PM mutex.
-
-	Never acquire udev->pm_mutex while holding the PM mutex for
-	a device that isn't a descendant of udev.
-
-In other words, PM mutexes should only be acquired going up the device
-tree, and they should be acquired only after locking all the device
-semaphores you need to hold.  These rules don't matter to drivers very
-much; they usually affect just the USB core.
-
-Still, drivers do need to be careful.  For example, many drivers use a
-private mutex to synchronize their normal I/O activities with their
-disconnect method.  Now if the driver supports autosuspend then it
-must call usb_autopm_put_interface() from somewhere -- maybe from its
-close method.  It should make the call while holding the private mutex,
-since a driver shouldn't call any of the usb_autopm_* functions for an
-interface from which it has been unbound.
-
-But the usb_autpm_* routines always acquire the device's PM mutex, and
-consequently the locking order has to be: private mutex first, PM
-mutex second.  Since the suspend method is always called with the PM
-mutex held, it mustn't try to acquire the private mutex.  It has to
-synchronize with the driver's I/O activities in some other way.
+critical section, the best way is to lock the device and call
+usb_autopm_get_interface() (and do the reverse at the end of the
+critical section).  Holding the device semaphore will block all
+external PM calls, and the usb_autopm_get_interface() will prevent any
+internal PM calls, even if it fails.  (Exercise: Why?)
 
 
 	Interaction between dynamic PM and system PM
···
 Dynamic power management and system power management can interact in
 a couple of ways.
 
-Firstly, a device may already be manually suspended or autosuspended
-when a system suspend occurs.  Since system suspends are supposed to
-be as transparent as possible, the device should remain suspended
-following the system resume.  The 2.6.23 kernel obeys this principle
-for manually suspended devices but not for autosuspended devices; they
-do get resumed when the system wakes up.  (Presumably they will be
-autosuspended again after their idle-delay time expires.)  In later
-kernels this behavior will be fixed.
-
-(There is an exception.  If a device would undergo a reset-resume
-instead of a normal resume, and the device is enabled for remote
-wakeup, then the reset-resume takes place even if the device was
-already suspended when the system suspend began.  The justification is
-that a reset-resume is a kind of remote-wakeup event.  Or to put it
-another way, a device which needs a reset won't be able to generate
-normal remote-wakeup signals, so it ought to be resumed immediately.)
+Firstly, a device may already be autosuspended when a system suspend
+occurs.  Since system suspends are supposed to be as transparent as
+possible, the device should remain suspended following the system
+resume.  But this theory may not work out well in practice; over time
+the kernel's behavior in this regard has changed.
 
 Secondly, a dynamic power-management event may occur as a system
 suspend is underway.  The window for this is short, since system

drivers/usb/core/Kconfig

···
 	  If you are unsure about this, say N here.
 
 config USB_SUSPEND
-	bool "USB selective suspend/resume and wakeup"
-	depends on USB && PM
+	bool "USB runtime power management (suspend/resume and wakeup)"
+	depends on USB && PM_RUNTIME
 	help
 	  If you say Y here, you can use driver calls or the sysfs
 	  "power/level" file to suspend or resume individual USB

drivers/usb/core/driver.c

···
 #include <linux/device.h>
 #include <linux/usb.h>
 #include <linux/usb/quirks.h>
-#include <linux/workqueue.h>
+#include <linux/pm_runtime.h>
 #include "hcd.h"
 #include "usb.h"
 
···
 {
 	struct usb_device_driver *udriver = to_usb_device_driver(dev->driver);
 	struct usb_device *udev = to_usb_device(dev);
-	int error = -ENODEV;
+	int error = 0;
 
 	dev_dbg(dev, "%s\n", __func__);
 
···
 	/* The device should always appear to be in use
 	 * unless the driver suports autosuspend.
 	 */
-	udev->pm_usage_cnt = !(udriver->supports_autosuspend);
+	if (!udriver->supports_autosuspend)
+		error = usb_autoresume_device(udev);
 
-	error = udriver->probe(udev);
+	if (!error)
+		error = udriver->probe(udev);
 	return error;
 }
 
 /* called from driver core with dev locked */
 static int usb_unbind_device(struct device *dev)
 {
+	struct usb_device *udev = to_usb_device(dev);
 	struct usb_device_driver *udriver = to_usb_device_driver(dev->driver);
 
-	udriver->disconnect(to_usb_device(dev));
+	udriver->disconnect(udev);
+	if (!udriver->supports_autosuspend)
+		usb_autosuspend_device(udev);
 	return 0;
 }
 
···
 	if (error)
 		return error;
 
-	/* Interface "power state" doesn't correspond to any hardware
-	 * state whatsoever.  We use it to record when it's bound to
-	 * a driver that may start I/0:  it's not frozen/quiesced.
-	 */
-	mark_active(intf);
 	intf->condition = USB_INTERFACE_BINDING;
 
-	/* The interface should always appear to be in use
-	 * unless the driver suports autosuspend.
+	/* Bound interfaces are initially active.  They are
+	 * runtime-PM-enabled only if the driver has autosuspend support.
+	 * They are sensitive to their children's power states.
 	 */
-	atomic_set(&intf->pm_usage_cnt, !driver->supports_autosuspend);
+	pm_runtime_set_active(dev);
+	pm_suspend_ignore_children(dev, false);
+	if (driver->supports_autosuspend)
+		pm_runtime_enable(dev);
 
 	/* Carry out a deferred switch to altsetting 0 */
 	if (intf->needs_altsetting0) {
···
 	return error;
 
  err:
-	mark_quiesced(intf);
 	intf->needs_remote_wakeup = 0;
 	intf->condition = USB_INTERFACE_UNBOUND;
 	usb_cancel_queued_reset(intf);
+
+	/* Unbound interfaces are always runtime-PM-disabled and -suspended */
+	pm_runtime_disable(dev);
+	pm_runtime_set_suspended(dev);
+
 	usb_autosuspend_device(udev);
 	return error;
 }
···
 	usb_set_intfdata(intf, NULL);
 
 	intf->condition = USB_INTERFACE_UNBOUND;
-	mark_quiesced(intf);
 	intf->needs_remote_wakeup = 0;
+
+	/* Unbound interfaces are always runtime-PM-disabled and -suspended */
+	pm_runtime_disable(dev);
+	pm_runtime_set_suspended(dev);
+
+	/* Undo any residual pm_autopm_get_interface_* calls */
+	for (r = atomic_read(&intf->pm_usage_cnt); r > 0; --r)
+		usb_autopm_put_interface_no_suspend(intf);
+	atomic_set(&intf->pm_usage_cnt, 0);
 
 	if (!error)
 		usb_autosuspend_device(udev);
···
 				struct usb_interface *iface, void *priv)
 {
 	struct device *dev = &iface->dev;
-	struct usb_device *udev = interface_to_usbdev(iface);
 	int retval = 0;
 
 	if (dev->driver)
···
 	usb_set_intfdata(iface, priv);
 	iface->needs_binding = 0;
 
-	usb_pm_lock(udev);
 	iface->condition = USB_INTERFACE_BOUND;
-	mark_active(iface);
-	atomic_set(&iface->pm_usage_cnt, !driver->supports_autosuspend);
-	usb_pm_unlock(udev);
+
+	/* Bound interfaces are initially active.  They are
+	 * runtime-PM-enabled only if the driver has autosuspend support.
+	 * They are sensitive to their children's power states.
+	 */
+	pm_runtime_set_active(dev);
+	pm_suspend_ignore_children(dev, false);
+	if (driver->supports_autosuspend)
+		pm_runtime_enable(dev);
 
 	/* if interface was already added, bind now; else let
 	 * the future device_add() bind it, bypassing probe()
···
 	}
 }
 
-/* Caller has locked udev's pm_mutex */
 static int usb_suspend_device(struct usb_device *udev, pm_message_t msg)
 {
 	struct usb_device_driver	*udriver;
···
 	return status;
 }
 
-/* Caller has locked udev's pm_mutex */
 static int usb_resume_device(struct usb_device *udev, pm_message_t msg)
 {
 	struct usb_device_driver	*udriver;
···
 	return status;
 }
 
-/* Caller has locked intf's usb_device's pm mutex */
 static int usb_suspend_interface(struct usb_device *udev,
 		struct usb_interface *intf, pm_message_t msg)
 {
 	struct usb_driver	*driver;
 	int			status = 0;
 
-	/* with no hardware, USB interfaces only use FREEZE and ON states */
-	if (udev->state == USB_STATE_NOTATTACHED || !is_active(intf))
-		goto done;
-
-	/* This can happen; see usb_driver_release_interface() */
-	if (intf->condition == USB_INTERFACE_UNBOUND)
+	if (udev->state == USB_STATE_NOTATTACHED ||
+			intf->condition == USB_INTERFACE_UNBOUND)
 		goto done;
 	driver = to_usb_driver(intf->dev.driver);
 
 	if (driver->suspend) {
 		status = driver->suspend(intf, msg);
-		if (status == 0)
-			mark_quiesced(intf);
-		else if (!(msg.event & PM_EVENT_AUTO))
+		if (status && !(msg.event & PM_EVENT_AUTO))
 			dev_err(&intf->dev, "%s error %d\n",
 					"suspend", status);
 	} else {
···
 		intf->needs_binding = 1;
 		dev_warn(&intf->dev, "no %s for driver %s?\n",
 				"suspend", driver->name);
-		mark_quiesced(intf);
 	}
 
  done:
···
 	return status;
 }
 
-/* Caller has locked intf's usb_device's pm_mutex */
 static int usb_resume_interface(struct usb_device *udev,
 		struct usb_interface *intf, pm_message_t msg, int reset_resume)
 {
 	struct usb_driver	*driver;
 	int			status = 0;
 
-	if (udev->state == USB_STATE_NOTATTACHED || is_active(intf))
+	if (udev->state == USB_STATE_NOTATTACHED)
 		goto done;
 
 	/* Don't let autoresume interfere with unbinding */
···
 
 done:
 	dev_vdbg(&intf->dev, "%s: status %d\n", __func__, status);
-	if (status == 0 && intf->condition == USB_INTERFACE_BOUND)
-		mark_active(intf);
 
 	/* Later we will unbind the driver and/or reprobe, if necessary */
 	return status;
 }
-
-#ifdef	CONFIG_USB_SUSPEND
-
-/* Internal routine to check whether we may autosuspend a device. */
-static int autosuspend_check(struct usb_device *udev, int reschedule)
-{
-	int			i;
-	struct usb_interface	*intf;
-	unsigned long		suspend_time, j;
-
-	/* For autosuspend, fail fast if anything is in use or autosuspend
-	 * is disabled.  Also fail if any interfaces require remote wakeup
-	 * but it isn't available.
-	 */
-	if (udev->pm_usage_cnt > 0)
-		return -EBUSY;
-	if (udev->autosuspend_delay < 0 || udev->autosuspend_disabled)
-		return -EPERM;
-
-	suspend_time = udev->last_busy + udev->autosuspend_delay;
-	if (udev->actconfig) {
-		for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
-			intf = udev->actconfig->interface[i];
-			if (!is_active(intf))
-				continue;
-			if (atomic_read(&intf->pm_usage_cnt) > 0)
-				return -EBUSY;
-			if (intf->needs_remote_wakeup &&
-					!udev->do_remote_wakeup) {
-				dev_dbg(&udev->dev, "remote wakeup needed "
-						"for autosuspend\n");
-				return -EOPNOTSUPP;
-			}
-
-			/* Don't allow autosuspend if the device will need
-			 * a reset-resume and any of its interface drivers
-			 * doesn't include support.
-			 */
-			if (udev->quirks & USB_QUIRK_RESET_RESUME) {
-				struct usb_driver *driver;
-
-				driver = to_usb_driver(intf->dev.driver);
-				if (!driver->reset_resume ||
-				    intf->needs_remote_wakeup)
-					return -EOPNOTSUPP;
-			}
-		}
-	}
-
-	/* If everything is okay but the device hasn't been idle for long
-	 * enough, queue a delayed autosuspend request.  If the device
-	 * _has_ been idle for long enough and the reschedule flag is set,
-	 * likewise queue a delayed (1 second) autosuspend request.
-	 */
-	j = jiffies;
-	if (time_before(j, suspend_time))
-		reschedule = 1;
-	else
-		suspend_time = j + HZ;
-	if (reschedule) {
-		if (!timer_pending(&udev->autosuspend.timer)) {
-			queue_delayed_work(ksuspend_usb_wq, &udev->autosuspend,
-				round_jiffies_up_relative(suspend_time - j));
-		}
-		return -EAGAIN;
-	}
-	return 0;
-}
-
-#else
-
-static inline int autosuspend_check(struct usb_device *udev, int reschedule)
-{
-	return 0;
-}
-
-#endif	/* CONFIG_USB_SUSPEND */
 
 /**
  * usb_suspend_both - suspend a USB device and its interfaces
···
  * all the interfaces which were suspended are resumed so that they remain
  * in the same state as the device.
  *
- * If an autosuspend is in progress the routine checks first to make sure
- * that neither the device itself or any of its active interfaces is in use
- * (pm_usage_cnt is greater than 0).  If they are, the autosuspend fails.
- *
- * If the suspend succeeds, the routine recursively queues an autosuspend
- * request for @udev's parent device, thereby propagating the change up
- * the device tree.  If all of the parent's children are now suspended,
- * the parent will autosuspend in turn.
- *
- * The suspend method calls are subject to mutual exclusion under control
- * of @udev's pm_mutex.  Many of these calls are also under the protection
- * of @udev's device lock (including all requests originating outside the
- * USB subsystem), but autosuspend requests generated by a child device or
- * interface driver may not be.  Usbcore will insure that the method calls
- * do not arrive during bind, unbind, or reset operations.  However, drivers
- * must be prepared to handle suspend calls arriving at unpredictable times.
- * The only way to block such calls is to do an autoresume (preventing
- * autosuspends) while holding @udev's device lock (preventing outside
- * suspends).
- *
- * The caller must hold @udev->pm_mutex.
+ * Autosuspend requests originating from a child device or an interface
+ * driver may be made without the protection of @udev's device lock, but
+ * all other suspend calls will hold the lock.  Usbcore will insure that
+ * method calls do not arrive during bind, unbind, or reset operations.
+ * However drivers must be prepared to handle suspend calls arriving at
+ * unpredictable times.
  *
  * This routine can run only in process context.
  */
···
 	int			status = 0;
 	int			i = 0;
 	struct usb_interface	*intf;
-	struct usb_device	*parent = udev->parent;
 
 	if (udev->state == USB_STATE_NOTATTACHED ||
 			udev->state == USB_STATE_SUSPENDED)
 		goto done;
-
-	udev->do_remote_wakeup = device_may_wakeup(&udev->dev);
-
-	if (msg.event & PM_EVENT_AUTO) {
-		status = autosuspend_check(udev, 0);
-		if (status < 0)
-			goto done;
-	}
 
 	/* Suspend all the interfaces and then udev itself */
 	if (udev->actconfig) {
···
 
 	/* If the suspend failed, resume interfaces that did get suspended */
 	if (status != 0) {
-		pm_message_t msg2;
-
-		msg2.event = msg.event ^ (PM_EVENT_SUSPEND | PM_EVENT_RESUME);
+		msg.event ^= (PM_EVENT_SUSPEND | PM_EVENT_RESUME);
 		while (--i >= 0) {
 			intf = udev->actconfig->interface[i];
-			usb_resume_interface(udev, intf, msg2, 0);
+			usb_resume_interface(udev, intf, msg, 0);
 		}
 
-		/* Try another autosuspend when the interfaces aren't busy */
-		if (msg.event & PM_EVENT_AUTO)
-			autosuspend_check(udev, status == -EBUSY);
-
-	/* If the suspend succeeded then prevent any more URB submissions,
-	 * flush any outstanding URBs, and propagate the suspend up the tree.
+	/* If the suspend succeeded then prevent any more URB submissions
+	 * and flush any outstanding URBs.
 	 */
 	} else {
-		cancel_delayed_work(&udev->autosuspend);
 		udev->can_submit = 0;
 		for (i = 0; i < 16; ++i) {
 			usb_hcd_flush_endpoint(udev, udev->ep_out[i]);
 			usb_hcd_flush_endpoint(udev, udev->ep_in[i]);
 		}
-
-		/* If this is just a FREEZE or a PRETHAW, udev might
-		 * not really be suspended.  Only true suspends get
-		 * propagated up the device tree.
-		 */
-		if (parent && udev->state == USB_STATE_SUSPENDED)
-			usb_autosuspend_device(parent);
 	}
 
  done:
···
  * the resume method for @udev and then calls the resume methods for all
  * the interface drivers in @udev.
  *
- * Before starting the resume, the routine calls itself recursively for
- * the parent device of @udev, thereby propagating the change up the device
- * tree and assuring that @udev will be able to resume.  If the parent is
- * unable to resume successfully, the routine fails.
- *
- * The resume method calls are subject to mutual exclusion under control
- * of @udev's pm_mutex.  Many of these calls are also under the protection
- * of @udev's device lock (including all requests originating outside the
- * USB subsystem), but autoresume requests generated by a child device or
- * interface driver may not be.  Usbcore will insure that the method calls
- * do not arrive during bind, unbind, or reset operations.  However, drivers
- * must be prepared to handle resume calls arriving at unpredictable times.
- * The only way to block such calls is to do an autoresume (preventing
- * other autoresumes) while holding @udev's device lock (preventing outside
- * resumes).
- *
- * The caller must hold @udev->pm_mutex.
+ * Autoresume requests originating from a child device or an interface
+ * driver may be made without the protection of @udev's device lock, but
+ * all other resume calls will hold the lock.  Usbcore will insure that
+ * method calls do not arrive during bind, unbind, or reset operations.
+ * However drivers must be prepared to handle resume calls arriving at
+ * unpredictable times.
  *
  * This routine can run only in process context.
  */
···
 	int			status = 0;
 	int			i;
 	struct usb_interface	*intf;
-	struct usb_device	*parent = udev->parent;
 
-	cancel_delayed_work(&udev->autosuspend);
 	if (udev->state == USB_STATE_NOTATTACHED) {
 		status = -ENODEV;
 		goto done;
 	}
 	udev->can_submit = 1;
 
-	/* Propagate the resume up the tree, if necessary */
-	if (udev->state == USB_STATE_SUSPENDED) {
-		if (parent) {
-			status = usb_autoresume_device(parent);
-			if (status == 0) {
-				status = usb_resume_device(udev, msg);
-				if (status || udev->state ==
-						USB_STATE_NOTATTACHED) {
-					usb_autosuspend_device(parent);
-
-					/* It's possible usb_resume_device()
-					 * failed after the port was
-					 * unsuspended, causing udev to be
-					 * logically disconnected.  We don't
-					 * want usb_disconnect() to autosuspend
-					 * the parent again, so tell it that
-					 * udev disconnected while still
-					 * suspended. */
-					if (udev->state ==
-							USB_STATE_NOTATTACHED)
-						udev->discon_suspended = 1;
-				}
-			}
-		} else {
-
-			/* We can't progagate beyond the USB subsystem,
-			 * so if a root hub's controller is suspended
-			 * then we're stuck. */
-			status = usb_resume_device(udev, msg);
-		}
-	} else if (udev->reset_resume)
+	/* Resume the device */
+	if (udev->state == USB_STATE_SUSPENDED || udev->reset_resume)
 		status = usb_resume_device(udev, msg);
 
+	/* Resume the interfaces */
 	if (status == 0 && udev->actconfig) {
 		for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
 			intf = udev->actconfig->interface[i];
···
 	return status;
 }
 
-/**
- * usb_external_suspend_device - external suspend of a USB device and its interfaces
- * @udev: the usb_device to suspend
- * @msg: Power Management message describing this state transition
- *
- * This routine handles external suspend requests: ones not generated
- * internally by a USB driver (autosuspend) but rather coming from the user
- * (via sysfs) or the PM core (system sleep).  The suspend will be carried
- * out regardless of @udev's usage counter or those of its interfaces,
- * and regardless of whether or not remote wakeup is enabled.  Of course,
- * interface drivers still have the option of failing the suspend (if
- * there are unsuspended children, for example).
- *
- * The caller must hold @udev's device lock.
- */
-int usb_external_suspend_device(struct usb_device *udev, pm_message_t msg)
-{
-	int	status;
-
-	do_unbind_rebind(udev, DO_UNBIND);
-	usb_pm_lock(udev);
-	status = usb_suspend_both(udev, msg);
-	usb_pm_unlock(udev);
-	return status;
-}
-
-/**
- * usb_external_resume_device - external resume of a USB device and its interfaces
- * @udev: the usb_device to resume
- * @msg: Power Management message describing this state transition
- *
- * This routine handles external resume requests: ones not generated
- * internally by a USB driver (autoresume) but rather coming from the user
- * (via sysfs), the PM core (system resume), or the device itself (remote
- * wakeup).  @udev's usage counter is unaffected.
- *
- * The caller must hold @udev's device lock.
- */
-int usb_external_resume_device(struct usb_device *udev, pm_message_t msg)
-{
-	int	status;
-
-	usb_pm_lock(udev);
-	status = usb_resume_both(udev, msg);
-	udev->last_busy = jiffies;
-	usb_pm_unlock(udev);
-	if (status == 0)
-		do_unbind_rebind(udev, DO_REBIND);
-
-	/* Now that the device is awake, we can start trying to autosuspend
-	 * it again. */
-	if (status == 0)
-		usb_try_autosuspend_device(udev);
-	return status;
-}
-
+/* The device lock is held by the PM core */
 int usb_suspend(struct device *dev, pm_message_t msg)
 {
-	struct usb_device	*udev;
+	struct usb_device	*udev = to_usb_device(dev);
 
-	udev = to_usb_device(dev);
-
-	/* If udev is already suspended, we can skip this suspend and
-	 * we should also skip the upcoming system resume.  High-speed
-	 * root hubs are an exception; they need to resume whenever the
-	 * system wakes up in order for USB-PERSIST port handover to work
-	 * properly.
-	 */
-	if (udev->state == USB_STATE_SUSPENDED) {
-		if (udev->parent || udev->speed != USB_SPEED_HIGH)
-			udev->skip_sys_resume = 1;
-		return 0;
-	}
-
-	udev->skip_sys_resume = 0;
-	return usb_external_suspend_device(udev, msg);
+	do_unbind_rebind(udev, DO_UNBIND);
+	udev->do_remote_wakeup = device_may_wakeup(&udev->dev);
+	return usb_suspend_both(udev, msg);
 }
 
+/* The device lock is held by the PM core */
 int usb_resume(struct device *dev, pm_message_t msg)
 {
-	struct usb_device	*udev;
+	struct usb_device	*udev = to_usb_device(dev);
 	int			status;
 
-	udev = to_usb_device(dev);
+	/* For PM complete calls, all we do is rebind interfaces */
+	if (msg.event == PM_EVENT_ON) {
+		if (udev->state != USB_STATE_NOTATTACHED)
+			do_unbind_rebind(udev, DO_REBIND);
+		status = 0;
 
-	/* If udev->skip_sys_resume is set then udev was already suspended
-	 * when the system sleep started, so we don't want to resume it
-	 * during this system wakeup.
+	/* For all other calls, take the device back to full power and
+	 * tell the PM core in case it was autosuspended previously.
 	 */
-	if (udev->skip_sys_resume)
-		return 0;
-	status = usb_external_resume_device(udev, msg);
+	} else {
+		status = usb_resume_both(udev, msg);
+		if (status == 0) {
+			pm_runtime_disable(dev);
+			pm_runtime_set_active(dev);
+			pm_runtime_enable(dev);
+			udev->last_busy = jiffies;
+		}
+	}
 
 	/* Avoid PM error messages for devices disconnected while suspended
 	 * as we'll display regular disconnect messages just a bit later.
 	 */
 	if (status == -ENODEV)
-		return 0;
+		status = 0;
 	return status;
 }
 
···
 }
 EXPORT_SYMBOL_GPL(usb_disable_autosuspend);
 
-/* Internal routine to adjust a device's usage counter and change
- * its autosuspend state.
- */
-static int usb_autopm_do_device(struct usb_device *udev, int inc_usage_cnt)
-{
-	int	status = 0;
-
-	usb_pm_lock(udev);
-	udev->pm_usage_cnt += inc_usage_cnt;
-	WARN_ON(udev->pm_usage_cnt < 0);
-	if (inc_usage_cnt)
-		udev->last_busy = jiffies;
-	if (inc_usage_cnt >= 0 && udev->pm_usage_cnt > 0) {
-		if (udev->state == USB_STATE_SUSPENDED)
-			status = usb_resume_both(udev, PMSG_AUTO_RESUME);
-		if (status != 0)
-			udev->pm_usage_cnt -= inc_usage_cnt;
-		else if (inc_usage_cnt)
-			udev->last_busy = jiffies;
-	} else if (inc_usage_cnt <= 0 && udev->pm_usage_cnt <= 0) {
-		status = usb_suspend_both(udev, PMSG_AUTO_SUSPEND);
-	}
-	usb_pm_unlock(udev);
-	return status;
-}
-
-/* usb_autosuspend_work - callback routine to autosuspend a USB device */
-void usb_autosuspend_work(struct work_struct *work)
-{
-	struct usb_device *udev =
-		container_of(work, struct usb_device, autosuspend.work);
-
-	usb_autopm_do_device(udev, 0);
-}
-
-/* usb_autoresume_work - callback routine to autoresume a USB device */
-void usb_autoresume_work(struct work_struct *work)
-{
-	struct usb_device *udev =
-		container_of(work, struct usb_device, autoresume);
-
-	/* Wake it up, let the drivers do their thing, and then put it
-	 * back to sleep.
-	 */
-	if (usb_autopm_do_device(udev, 1) == 0)
-		usb_autopm_do_device(udev, -1);
-}
-
 /**
  * usb_autosuspend_device - delayed autosuspend of a USB device and its interfaces
  * @udev: the usb_device to autosuspend
···
  * @udev and wants to allow it to autosuspend.  Examples would be when
  * @udev's device file in usbfs is closed or after a configuration change.
  *
- * @udev's usage counter is decremented.  If it or any of the usage counters
- * for an active interface is greater than 0, no autosuspend request will be
- * queued.  (If an interface driver does not support autosuspend then its
- * usage counter is permanently positive.)  Furthermore, if an interface
- * driver requires remote-wakeup capability during autosuspend but remote
- * wakeup is disabled, the autosuspend will fail.
+ * @udev's usage counter is decremented; if it drops to 0 and all the
+ * interfaces are inactive then a delayed autosuspend will be attempted.
+ * The attempt may fail (see autosuspend_check()).
  *
  * The caller must hold @udev's device lock.
  *
···
 {
 	int	status;
 
-	status = usb_autopm_do_device(udev, -1);
-	dev_vdbg(&udev->dev, "%s: cnt %d\n",
-			__func__, udev->pm_usage_cnt);
+	udev->last_busy = jiffies;
+	status = pm_runtime_put_sync(&udev->dev);
+	dev_vdbg(&udev->dev, "%s: cnt %d -> %d\n",
+			__func__, atomic_read(&udev->dev.power.usage_count),
+			status);
 }
 
 /**
···
  * This routine should be called when a core subsystem thinks @udev may
  * be ready to autosuspend.
  *
- * @udev's usage counter left unchanged.  If it or any of the usage counters
- * for an active interface is greater than 0, or autosuspend is not allowed
- * for any other reason, no autosuspend request will be queued.
+ * @udev's usage counter left unchanged.  If it is 0 and all the interfaces
+ * are inactive then an autosuspend will be attempted.  The attempt may
+ * fail or be delayed.
  *
  * The caller must hold @udev's device lock.
  *
···
  */
 void usb_try_autosuspend_device(struct usb_device *udev)
 {
-	usb_autopm_do_device(udev, 0);
-	dev_vdbg(&udev->dev, "%s: cnt %d\n",
-			__func__, udev->pm_usage_cnt);
+	int	status;
+
+	status = pm_runtime_idle(&udev->dev);
+	dev_vdbg(&udev->dev, "%s: cnt %d -> %d\n",
+			__func__, atomic_read(&udev->dev.power.usage_count),
+			status);
 }
 
 /**
···
  *
  * This routine should be called when a core subsystem wants to use @udev
  * and needs to guarantee that it is not suspended.  No autosuspend will
- * occur until usb_autosuspend_device is called.  (Note that this will not
- * prevent suspend events originating in the PM core.)  Examples would be
- * when @udev's device file in usbfs is opened or when a remote-wakeup
+ * occur until usb_autosuspend_device() is called.  (Note that this will
+ * not prevent suspend events originating in the PM core.)  Examples would
+ * be when @udev's device file in usbfs is opened or when a remote-wakeup
  * request is received.
  *
  * @udev's usage counter is incremented to prevent subsequent autosuspends.
···
 {
 	int	status;
 
-	status = usb_autopm_do_device(udev, 1);
-	dev_vdbg(&udev->dev, "%s: status %d cnt %d\n",
-			__func__, status, udev->pm_usage_cnt);
-	return status;
-}
-
-/* Internal routine to adjust an interface's usage counter and change
- * its device's autosuspend state.
- */
-static int usb_autopm_do_interface(struct usb_interface *intf,
-		int inc_usage_cnt)
-{
-	struct usb_device	*udev = interface_to_usbdev(intf);
-	int			status = 0;
-
-	usb_pm_lock(udev);
-	if (intf->condition == USB_INTERFACE_UNBOUND)
-		status = -ENODEV;
-	else {
-		atomic_add(inc_usage_cnt, &intf->pm_usage_cnt);
-		udev->last_busy = jiffies;
-		if (inc_usage_cnt >= 0 &&
-				atomic_read(&intf->pm_usage_cnt) > 0) {
-			if (udev->state == USB_STATE_SUSPENDED)
-				status = usb_resume_both(udev,
-						PMSG_AUTO_RESUME);
-			if (status != 0)
-				atomic_sub(inc_usage_cnt, &intf->pm_usage_cnt);
-			else
-				udev->last_busy = jiffies;
-		} else if (inc_usage_cnt <= 0 &&
-				atomic_read(&intf->pm_usage_cnt) <= 0) {
-			status = usb_suspend_both(udev, PMSG_AUTO_SUSPEND);
-		}
-	}
-	usb_pm_unlock(udev);
+	status = pm_runtime_get_sync(&udev->dev);
+	if (status < 0)
+		pm_runtime_put_sync(&udev->dev);
+	dev_vdbg(&udev->dev, "%s: cnt %d -> %d\n",
+			__func__, atomic_read(&udev->dev.power.usage_count),
+			status);
+	if (status > 0)
+		status = 0;
 	return status;
 }
 
···
  * closed.
  *
  * The routine decrements @intf's usage counter.  When the counter reaches
- * 0, a delayed autosuspend request for @intf's device is queued.  When
- * the delay expires, if @intf->pm_usage_cnt is still <= 0 along with all
- * the other usage counters for the sibling interfaces and @intf's
- * usb_device, the device and all its interfaces will be autosuspended.
- *
- * Note that @intf->pm_usage_cnt is owned by the interface driver.  The
- * core will not change its value other than the increment and decrement
- * in usb_autopm_get_interface and usb_autopm_put_interface.  The driver
- * may use this simple counter-oriented discipline or may set the value
- * any way it likes.
+ * 0, a delayed autosuspend request for @intf's device is attempted.  The
+ * attempt may fail (see autosuspend_check()).
  *
  * If the driver has set @intf->needs_remote_wakeup then autosuspend will
  * take place only if the device's remote-wakeup facility is enabled.
- *
- * Suspend method calls queued by this routine can arrive at any time
- * while @intf is resumed and its usage counter is equal to 0.  They are
- * not protected by the usb_device's lock but only by its pm_mutex.
- * Drivers must provide their own synchronization.
  *
  * This routine can run only in process context.
  */
 void usb_autopm_put_interface(struct usb_interface *intf)
 {
-	int	status;
+	struct usb_device	*udev = interface_to_usbdev(intf);
+	int			status;
 
-	status = usb_autopm_do_interface(intf, -1);
-	dev_vdbg(&intf->dev, "%s: status %d cnt %d\n",
-			__func__, status, atomic_read(&intf->pm_usage_cnt));
+	udev->last_busy = jiffies;
+	atomic_dec(&intf->pm_usage_cnt);
+	status = pm_runtime_put_sync(&intf->dev);
+	dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n",
+			__func__, atomic_read(&intf->dev.power.usage_count),
+			status);
 }
 EXPORT_SYMBOL_GPL(usb_autopm_put_interface);
 
···
  * usb_autopm_put_interface_async - decrement a USB interface's PM-usage counter
  * @intf: the usb_interface whose counter should be decremented
  *
- * This routine does essentially the same thing as
- * usb_autopm_put_interface(): it decrements @intf's usage counter and
- * queues a delayed autosuspend request if the counter is <= 0.  The
- * difference is that it does not acquire the device's pm_mutex;
- * callers must handle all synchronization issues themselves.
+ * This routine does much the same thing as usb_autopm_put_interface():
+ * It decrements @intf's usage counter and schedules a delayed
+ * autosuspend request if the counter is <= 0.  The difference is that it
+ * does not perform any synchronization; callers should hold a private
+ * lock and handle all synchronization issues themselves.
  *
  * Typically a driver would call this routine during an URB's completion
  * handler, if no more URBs were pending.
···
 void usb_autopm_put_interface_async(struct usb_interface *intf)
 {
 	struct usb_device	*udev = interface_to_usbdev(intf);
+	unsigned long		last_busy;
 	int			status = 0;
 
-	if (intf->condition == USB_INTERFACE_UNBOUND) {
-		status = -ENODEV;
-	} else {
-		udev->last_busy = jiffies;
-		atomic_dec(&intf->pm_usage_cnt);
-		if (udev->autosuspend_disabled || udev->autosuspend_delay < 0)
-			status = -EPERM;
-		else if (atomic_read(&intf->pm_usage_cnt) <= 0 &&
-				!timer_pending(&udev->autosuspend.timer)) {
-			queue_delayed_work(ksuspend_usb_wq, &udev->autosuspend,
+	last_busy = udev->last_busy;
+	udev->last_busy = jiffies;
+	atomic_dec(&intf->pm_usage_cnt);
+	pm_runtime_put_noidle(&intf->dev);
+
+	if (!udev->autosuspend_disabled) {
+		/* Optimization: Don't schedule a delayed autosuspend if
+		 * the timer is already running and the expiration time
+		 * wouldn't change.
+		 *
+		 * We have to use the interface's timer.  Attempts to
+		 * schedule a suspend for the device would fail because
+		 * the interface is still active.
+		 */
+		if (intf->dev.power.timer_expires == 0 ||
+				round_jiffies_up(last_busy) !=
+				round_jiffies_up(jiffies)) {
+			status = pm_schedule_suspend(&intf->dev,
+					jiffies_to_msecs(
 					round_jiffies_up_relative(
-						udev->autosuspend_delay));
+						udev->autosuspend_delay)));
 		}
 	}
-	dev_vdbg(&intf->dev, "%s: status %d cnt %d\n",
-			__func__, status, atomic_read(&intf->pm_usage_cnt));
+	dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n",
+			__func__, atomic_read(&intf->dev.power.usage_count),
+			status);
 }
 EXPORT_SYMBOL_GPL(usb_autopm_put_interface_async);
+
+/**
+ * usb_autopm_put_interface_no_suspend - decrement a USB interface's PM-usage counter
+ * @intf: the usb_interface whose counter should be decremented
+ *
+ * This routine decrements @intf's usage counter but does not carry out an
+ * autosuspend.
+ *
+ * This routine can run in atomic context.
+ */
+void usb_autopm_put_interface_no_suspend(struct usb_interface *intf)
+{
+	struct usb_device	*udev = interface_to_usbdev(intf);
+
+	udev->last_busy = jiffies;
+	atomic_dec(&intf->pm_usage_cnt);
+	pm_runtime_put_noidle(&intf->dev);
+}
+EXPORT_SYMBOL_GPL(usb_autopm_put_interface_no_suspend);
 
 /**
  * usb_autopm_get_interface - increment a USB interface's PM-usage counter
···
  * or @intf is unbound.  A typical example would be a character-device
  * driver when its device file is opened.
  *
- *
- * The routine increments @intf's usage counter.  (However if the
- * autoresume fails then the counter is re-decremented.)  So long as the
- * counter is greater than 0, autosuspend will not be allowed for @intf
- * or its usb_device.  When the driver is finished using @intf it should
- * call usb_autopm_put_interface() to decrement the usage counter and
- * queue a delayed autosuspend request (if the counter is <= 0).
- *
- *
- * Note that @intf->pm_usage_cnt is owned by the interface driver.  The
- * core will not change its value other than the increment and decrement
- * in usb_autopm_get_interface and usb_autopm_put_interface.  The driver
- * may use this simple counter-oriented discipline or may set the value
- * any way it likes.
- *
- * Resume method calls generated by this routine can arrive at any time
- * while @intf is suspended.  They are not protected by the usb_device's
- * lock but only by its pm_mutex.  Drivers must provide their own
- * synchronization.
+ * @intf's usage counter is incremented to prevent subsequent autosuspends.
+ * However if the autoresume fails then the counter is re-decremented.
  *
  * This routine can run only in process context.
  */
···
 {
 	int	status;
 
-	status = usb_autopm_do_interface(intf, 1);
-	dev_vdbg(&intf->dev, "%s: status %d cnt %d\n",
-			__func__, status, atomic_read(&intf->pm_usage_cnt));
+	status = pm_runtime_get_sync(&intf->dev);
+	if (status < 0)
+		pm_runtime_put_sync(&intf->dev);
+	else
+		atomic_inc(&intf->pm_usage_cnt);
+	dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n",
+			__func__, atomic_read(&intf->dev.power.usage_count),
+			status);
+	if (status > 0)
+		status = 0;
 	return status;
 }
 EXPORT_SYMBOL_GPL(usb_autopm_get_interface);
···
  * @intf: the usb_interface whose counter should be incremented
  *
  * This routine does much the same thing as
- * usb_autopm_get_interface(): it increments @intf's usage counter and
- * queues an autoresume request if the result is > 0.  The differences
- * are that it does not acquire the device's pm_mutex (callers must
- * handle all synchronization issues themselves), and it does not
- * autoresume the device directly (it only queues a request).  After a
- * successful call, the device will generally not yet be resumed.
+ * usb_autopm_get_interface(): It increments @intf's usage counter and
+ * queues an autoresume request if the device is suspended.  The
+ * differences are that it does not perform any synchronization (callers
+ * should hold a private lock and handle all synchronization issues
+ * themselves), and it does not autoresume the device directly (it only
+ * queues a request).  After a successful call, the device may not yet be
+ * resumed.
  *
  * This routine can run in atomic context.
  */
 int usb_autopm_get_interface_async(struct usb_interface *intf)
 {
-	struct usb_device	*udev = interface_to_usbdev(intf);
-	int			status = 0;
+	int		status = 0;
+	enum rpm_status	s;
 
-	if (intf->condition == USB_INTERFACE_UNBOUND)
-		status = -ENODEV;
-	else {
+	/* Don't request a resume unless the interface is already suspending
+	 * or suspended.  Doing so would force a running suspend timer to be
+	 * cancelled.
+	 */
+	pm_runtime_get_noresume(&intf->dev);
+	s = ACCESS_ONCE(intf->dev.power.runtime_status);
+	if (s == RPM_SUSPENDING || s == RPM_SUSPENDED)
+		status = pm_request_resume(&intf->dev);
+
+	if (status < 0 && status != -EINPROGRESS)
+		pm_runtime_put_noidle(&intf->dev);
+	else
 		atomic_inc(&intf->pm_usage_cnt);
-		if (atomic_read(&intf->pm_usage_cnt) > 0 &&
-				udev->state == USB_STATE_SUSPENDED)
-			queue_work(ksuspend_usb_wq, &udev->autoresume);
-	}
-	dev_vdbg(&intf->dev, "%s: status %d cnt %d\n",
-			__func__, status, atomic_read(&intf->pm_usage_cnt));
+	dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n",
+			__func__, atomic_read(&intf->dev.power.usage_count),
+			status);
+	if (status > 0)
+		status = 0;
 	return status;
 }
 EXPORT_SYMBOL_GPL(usb_autopm_get_interface_async);
 
+/**
+ * usb_autopm_get_interface_no_resume - increment a USB interface's PM-usage counter
+ * @intf: the usb_interface whose counter should be incremented
+ *
+ * This routine increments @intf's usage counter but does not carry out an
+ * autoresume.
+ *
+ * This routine can run in atomic context.
+ */
+void usb_autopm_get_interface_no_resume(struct usb_interface *intf)
+{
+	struct usb_device	*udev = interface_to_usbdev(intf);
+
+	udev->last_busy = jiffies;
+	atomic_inc(&intf->pm_usage_cnt);
+	pm_runtime_get_noresume(&intf->dev);
+}
+EXPORT_SYMBOL_GPL(usb_autopm_get_interface_no_resume);
+
+/* Internal routine to check whether we may autosuspend a device. */
+static int autosuspend_check(struct usb_device *udev)
+{
+	int			i;
+	struct usb_interface	*intf;
+	unsigned long		suspend_time, j;
+
+	/* Fail if autosuspend is disabled, or any interfaces are in use, or
+	 * any interface drivers require remote wakeup but it isn't available.
+	 */
+	udev->do_remote_wakeup = device_may_wakeup(&udev->dev);
+	if (udev->actconfig) {
+		for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
+			intf = udev->actconfig->interface[i];
+
+			/* We don't need to check interfaces that are
+			 * disabled for runtime PM.  Either they are unbound
+			 * or else their drivers don't support autosuspend
+			 * and so they are permanently active.
+			 */
+			if (intf->dev.power.disable_depth)
+				continue;
+			if (atomic_read(&intf->dev.power.usage_count) > 0)
+				return -EBUSY;
+			if (intf->needs_remote_wakeup &&
+					!udev->do_remote_wakeup) {
+				dev_dbg(&udev->dev, "remote wakeup needed "
+						"for autosuspend\n");
+				return -EOPNOTSUPP;
+			}
+
+			/* Don't allow autosuspend if the device will need
+			 * a reset-resume and any of its interface drivers
+			 * doesn't include support or needs remote wakeup.
+			 */
+			if (udev->quirks & USB_QUIRK_RESET_RESUME) {
+				struct usb_driver *driver;
+
+				driver = to_usb_driver(intf->dev.driver);
+				if (!driver->reset_resume ||
+						intf->needs_remote_wakeup)
+					return -EOPNOTSUPP;
+			}
+		}
+	}
+
+	/* If everything is okay but the device hasn't been idle for long
+	 * enough, queue a delayed autosuspend request.
+	 */
+	j = ACCESS_ONCE(jiffies);
+	suspend_time = udev->last_busy + udev->autosuspend_delay;
+	if (time_before(j, suspend_time)) {
+		pm_schedule_suspend(&udev->dev, jiffies_to_msecs(
+				round_jiffies_up_relative(suspend_time - j)));
+		return -EAGAIN;
+	}
+	return 0;
+}
+
+static int usb_runtime_suspend(struct device *dev)
+{
+	int	status = 0;
+
+	/* A USB device can be suspended if it passes the various autosuspend
+	 * checks.  Runtime suspend for a USB device means suspending all the
+	 * interfaces and then the device itself.
+	 */
+	if (is_usb_device(dev)) {
+		struct usb_device	*udev = to_usb_device(dev);
+
+		if (autosuspend_check(udev) != 0)
+			return -EAGAIN;
+
+		status = usb_suspend_both(udev, PMSG_AUTO_SUSPEND);
+
+		/* If an interface fails the suspend, adjust the last_busy
+		 * time so that we don't get another suspend attempt right
+		 * away.
+		 */
+		if (status) {
+			udev->last_busy = jiffies +
+					(udev->autosuspend_delay == 0 ?
+						HZ/2 : 0);
+		}
+
+		/* Prevent the parent from suspending immediately after */
+		else if (udev->parent) {
+			udev->parent->last_busy = jiffies;
+		}
+	}
+
+	/* Runtime suspend for a USB interface doesn't mean anything. */
+	return status;
+}
+
+static int usb_runtime_resume(struct device *dev)
+{
+	/* Runtime resume for a USB device means resuming both the device
+	 * and all its interfaces.
+	 */
+	if (is_usb_device(dev)) {
+		struct usb_device	*udev = to_usb_device(dev);
+		int			status;
+
+		status = usb_resume_both(udev, PMSG_AUTO_RESUME);
+		udev->last_busy = jiffies;
+		return status;
+	}
+
+	/* Runtime resume for a USB interface doesn't mean anything. */
+	return 0;
+}
+
+static int usb_runtime_idle(struct device *dev)
+{
+	/* An idle USB device can be suspended if it passes the various
+	 * autosuspend checks.  An idle interface can be suspended at
+	 * any time.
+	 */
+	if (is_usb_device(dev)) {
+		struct usb_device	*udev = to_usb_device(dev);
+
+		if (autosuspend_check(udev) != 0)
+			return 0;
+	}
+
+	pm_runtime_suspend(dev);
+	return 0;
+}
+
+static struct dev_pm_ops usb_bus_pm_ops = {
+	.runtime_suspend =	usb_runtime_suspend,
+	.runtime_resume =	usb_runtime_resume,
+	.runtime_idle =		usb_runtime_idle,
+};
+
 #else
 
-void usb_autosuspend_work(struct work_struct *work)
-{}
-
-void usb_autoresume_work(struct work_struct *work)
-{}
+#define usb_bus_pm_ops	(*(struct dev_pm_ops *) NULL)
 
 #endif /* CONFIG_USB_SUSPEND */
 
···
 	.name =		"usb",
 	.match =	usb_device_match,
 	.uevent =	usb_uevent,
+	.pm =		&usb_bus_pm_ops,
 };

drivers/usb/core/hcd.c

···
 #include <linux/platform_device.h>
 #include <linux/workqueue.h>
 #include <linux/mutex.h>
+#include <linux/pm_runtime.h>
 
 #include <linux/usb.h>
 
···
 	return status;
 }
 
+#endif	/* CONFIG_PM */
+
+#ifdef	CONFIG_USB_SUSPEND
+
 /* Workqueue routine for root-hub remote wakeup */
 static void hcd_resume_work(struct work_struct *work)
 {
···
 
 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
 	if (hcd->rh_registered)
-		queue_work(ksuspend_usb_wq, &hcd->wakeup_work);
+		queue_work(pm_wq, &hcd->wakeup_work);
 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
 }
 EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
 
-#endif
+#endif	/* CONFIG_USB_SUSPEND */
 
 /*-------------------------------------------------------------------------*/
 
···
 	init_timer(&hcd->rh_timer);
 	hcd->rh_timer.function = rh_timer_func;
 	hcd->rh_timer.data = (unsigned long) hcd;
-#ifdef CONFIG_PM
+#ifdef CONFIG_USB_SUSPEND
 	INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
 #endif
 	mutex_init(&hcd->bandwidth_mutex);
···
 	hcd->rh_registered = 0;
 	spin_unlock_irq (&hcd_root_hub_lock);
 
-#ifdef CONFIG_PM
+#ifdef CONFIG_USB_SUSPEND
 	cancel_work_sync(&hcd->wakeup_work);
 #endif
 

drivers/usb/core/hcd.h

···
 
 	struct timer_list	rh_timer;	/* drives root-hub polling */
 	struct urb		*status_urb;	/* the current status urb */
-#ifdef CONFIG_PM
+#ifdef CONFIG_USB_SUSPEND
 	struct work_struct	wakeup_work;	/* for remote wakeup */
 #endif
 
···
 #define usb_endpoint_out(ep_dir)	(!((ep_dir) & USB_DIR_IN))
 
 #ifdef CONFIG_PM
-extern void usb_hcd_resume_root_hub(struct usb_hcd *hcd);
 extern void usb_root_hub_lost_power(struct usb_device *rhdev);
 extern int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg);
 extern int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg);
+#endif /* CONFIG_PM */
+
+#ifdef CONFIG_USB_SUSPEND
+extern void usb_hcd_resume_root_hub(struct usb_hcd *hcd);
 #else
 static inline void usb_hcd_resume_root_hub(struct usb_hcd *hcd)
 {
 	return;
 }
-#endif /* CONFIG_PM */
+#endif /* CONFIG_USB_SUSPEND */
+
 
 /*
  * USB device fs stuff

drivers/usb/core/hub.c

···
 #include <linux/kthread.h>
 #include <linux/mutex.h>
 #include <linux/freezer.h>
+#include <linux/pm_runtime.h>
 
 #include <asm/uaccess.h>
 #include <asm/byteorder.h>
···
 
 	unsigned		mA_per_port;	/* current for each child */
 
-	unsigned		init_done:1;
 	unsigned		limited_power:1;
 	unsigned		quiescing:1;
 	unsigned		disconnected:1;
···
 	}
  init3:
 	hub->quiescing = 0;
-	hub->init_done = 1;
 
 	status = usb_submit_urb(hub->urb, GFP_NOIO);
 	if (status < 0)
···
 	int i;
 
 	cancel_delayed_work_sync(&hub->init_work);
-	if (!hub->init_done) {
-		hub->init_done = 1;
-		usb_autopm_put_interface_no_suspend(
-				to_usb_interface(hub->intfdev));
-	}
 
 	/* khubd and related activity won't re-trigger */
 	hub->quiescing = 1;
···
 		if (udev->children[i])
 			recursively_mark_NOTATTACHED(udev->children[i]);
 	}
-	if (udev->state == USB_STATE_SUSPENDED) {
-		udev->discon_suspended = 1;
+	if (udev->state == USB_STATE_SUSPENDED)
 		udev->active_duration -= jiffies;
-	}
 	udev->state = USB_STATE_NOTATTACHED;
 }
 
···
 		udev->devnum = devnum;
 }
 
-#ifdef	CONFIG_USB_SUSPEND
-
-static void usb_stop_pm(struct usb_device *udev)
-{
-	/* Synchronize with the ksuspend thread to prevent any more
-	 * autosuspend requests from being submitted, and decrement
-	 * the parent's count of unsuspended children.
-	 */
-	usb_pm_lock(udev);
-	if (udev->parent && !udev->discon_suspended)
-		usb_autosuspend_device(udev->parent);
-	usb_pm_unlock(udev);
-
-	/* Stop any autosuspend or autoresume requests already submitted */
-	cancel_delayed_work_sync(&udev->autosuspend);
-	cancel_work_sync(&udev->autoresume);
-}
-
-#else
-
-static inline void usb_stop_pm(struct usb_device *udev)
-{ }
-
-#endif
-
 /**
  * usb_disconnect - disconnect a device (usbcore-internal)
  * @pdev: pointer to device being disconnected
···
 	spin_lock_irq(&device_state_lock);
 	*pdev = NULL;
 	spin_unlock_irq(&device_state_lock);
-
-	usb_stop_pm(udev);
 
 	put_device(&udev->dev);
 }
···
 	int err;
 
 	if (udev->parent) {
-		/* Increment the parent's count of unsuspended children */
-		usb_autoresume_device(udev->parent);
-
 		/* Initialize non-root-hub device wakeup to disabled;
 		 * device (un)configuration controls wakeup capable
 		 * sysfs power/wakeup controls wakeup enabled/disabled
···
 		device_init_wakeup(&udev->dev, 0);
 		device_set_wakeup_enable(&udev->dev, 1);
 	}
+
+	/* Tell the runtime-PM framework the device is active */
+	pm_runtime_set_active(&udev->dev);
+	pm_runtime_enable(&udev->dev);
 
 	usb_detect_quirks(udev);
 	err = usb_enumerate_device(udev);	/* Read descriptors */
···
 
 fail:
 	usb_set_device_state(udev, USB_STATE_NOTATTACHED);
-	usb_stop_pm(udev);
+	pm_runtime_disable(&udev->dev);
+	pm_runtime_set_suspended(&udev->dev);
 	return err;
 }
 
···
 
 	if (udev->state == USB_STATE_SUSPENDED) {
 		dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
-		usb_mark_last_busy(udev);
-		status = usb_external_resume_device(udev, PMSG_REMOTE_RESUME);
+		status = usb_autoresume_device(udev);
+		if (status == 0) {
+			/* Let the drivers do their thing, then... */
+			usb_autosuspend_device(udev);
+		}
 	}
 	return status;
 }
···
 		status = usb_reset_and_verify_device(udev);
 	}
 	return status;
-}
-
-int usb_remote_wakeup(struct usb_device *udev)
-{
-	return 0;
 }
 
 #endif
···
 		 * disconnected while waiting for the lock to succeed. */
 		usb_lock_device(hdev);
 		if (unlikely(hub->disconnected))
-			goto loop2;
+			goto loop_disconnected;
 
 		/* If the hub has died, clean up after it */
 		if (hdev->state == USB_STATE_NOTATTACHED) {
···
 		 * kick_khubd() and allow autosuspend.
 		 */
 		usb_autopm_put_interface(intf);
- loop2:
+ loop_disconnected:
 		usb_unlock_device(hdev);
 		kref_put(&hub->kref, hub_release);
 

drivers/usb/core/message.c

···
 		intf->dev.dma_mask = dev->dev.dma_mask;
 		INIT_WORK(&intf->reset_ws, __usb_queue_reset_device);
 		device_initialize(&intf->dev);
-		mark_quiesced(intf);
 		dev_set_name(&intf->dev, "%d-%s:%d.%d",
 			dev->bus->busnum, dev->devpath,
 			configuration, alt->desc.bInterfaceNumber);

drivers/usb/core/usb.c

···
 
 static int nousb;	/* Disable USB when built into kernel image */
 
-/* Workqueue for autosuspend and for remote wakeup of root hubs */
-struct workqueue_struct *ksuspend_usb_wq;
-
 #ifdef	CONFIG_USB_SUSPEND
 static int usb_autosuspend_delay = 2;		/* Default delay value,
 						 * in seconds */
···
 
 #ifdef	CONFIG_PM
 
-static int ksuspend_usb_init(void)
-{
-	/* This workqueue is supposed to be both freezable and
-	 * singlethreaded.  Its job doesn't justify running on more
-	 * than one CPU.
-	 */
-	ksuspend_usb_wq = create_freezeable_workqueue("ksuspend_usbd");
-	if (!ksuspend_usb_wq)
-		return -ENOMEM;
-	return 0;
-}
-
-static void ksuspend_usb_cleanup(void)
-{
-	destroy_workqueue(ksuspend_usb_wq);
-}
-
 /* USB device Power-Management thunks.
  * There's no need to distinguish here between quiescing a USB device
  * and powering it down; the generic_suspend() routine takes care of
···
 static void usb_dev_complete(struct device *dev)
 {
 	/* Currently used only for rebinding interfaces */
-	usb_resume(dev, PMSG_RESUME);	/* Message event is meaningless */
+	usb_resume(dev, PMSG_ON);	/* FIXME: change to PMSG_COMPLETE */
 }
 
 static int usb_dev_suspend(struct device *dev)
···
 
 #else
 
-#define ksuspend_usb_init()	0
-#define ksuspend_usb_cleanup()	do {} while (0)
-#define usb_device_pm_ops	(*(struct dev_pm_ops *)0)
+#define usb_device_pm_ops	(*(struct dev_pm_ops *) NULL)
 
 #endif	/* CONFIG_PM */
 
···
 	INIT_LIST_HEAD(&dev->filelist);
 
 #ifdef	CONFIG_PM
-	mutex_init(&dev->pm_mutex);
-	INIT_DELAYED_WORK(&dev->autosuspend, usb_autosuspend_work);
-	INIT_WORK(&dev->autoresume, usb_autoresume_work);
 	dev->autosuspend_delay = usb_autosuspend_delay * HZ;
 	dev->connect_time = jiffies;
 	dev->active_duration = -jiffies;
···
 	if (retval)
 		goto out;
 
-	retval = ksuspend_usb_init();
-	if (retval)
-		goto out;
 	retval = bus_register(&usb_bus_type);
 	if (retval)
 		goto bus_register_failed;
···
 bus_notifier_failed:
 	bus_unregister(&usb_bus_type);
 bus_register_failed:
-	ksuspend_usb_cleanup();
+	usb_debugfs_cleanup();
 out:
 	return retval;
 }
···
 	usb_hub_cleanup();
 	bus_unregister_notifier(&usb_bus_type, &usb_bus_nb);
 	bus_unregister(&usb_bus_type);
-	ksuspend_usb_cleanup();
 	usb_debugfs_cleanup();
 }
 

drivers/usb/core/usb.h

···
 extern int usb_suspend(struct device *dev, pm_message_t msg);
 extern int usb_resume(struct device *dev, pm_message_t msg);
 
-extern void usb_autosuspend_work(struct work_struct *work);
-extern void usb_autoresume_work(struct work_struct *work);
 extern int usb_port_suspend(struct usb_device *dev, pm_message_t msg);
 extern int usb_port_resume(struct usb_device *dev, pm_message_t msg);
-extern int usb_external_suspend_device(struct usb_device *udev,
-		pm_message_t msg);
-extern int usb_external_resume_device(struct usb_device *udev,
-		pm_message_t msg);
-extern int usb_remote_wakeup(struct usb_device *dev);
-
-static inline void usb_pm_lock(struct usb_device *udev)
-{
-	mutex_lock_nested(&udev->pm_mutex, udev->level);
-}
-
-static inline void usb_pm_unlock(struct usb_device *udev)
-{
-	mutex_unlock(&udev->pm_mutex);
-}
 
 #else
 
···
 	return 0;
 }
 
-static inline int usb_remote_wakeup(struct usb_device *udev)
-{
-	return 0;
-}
-
-static inline void usb_pm_lock(struct usb_device *udev) {}
-static inline void usb_pm_unlock(struct usb_device *udev) {}
-
 #endif
 
 #ifdef CONFIG_USB_SUSPEND
···
 extern void usb_autosuspend_device(struct usb_device *udev);
 extern void usb_try_autosuspend_device(struct usb_device *udev);
 extern int usb_autoresume_device(struct usb_device *udev);
+extern int usb_remote_wakeup(struct usb_device *dev);
 
 #else
 
···
 	return 0;
 }
 
+static inline int usb_remote_wakeup(struct usb_device *udev)
+{
+	return 0;
+}
+
 #endif
 
-extern struct workqueue_struct *ksuspend_usb_wq;
 extern struct bus_type usb_bus_type;
 extern struct device_type usb_device_type;
 extern struct device_type usb_if_device_type;
···
 {
 	return container_of(drv, struct usbdrv_wrap, driver)->
 			for_devices;
-}
-
-/* Interfaces and their "power state" are owned by usbcore */
-
-static inline void mark_active(struct usb_interface *f)
-{
-	f->is_active = 1;
-}
-
-static inline void mark_quiesced(struct usb_interface *f)
-{
-	f->is_active = 0;
-}
-
-static inline int is_active(const struct usb_interface *f)
-{
-	return f->is_active;
 }
 
 

drivers/usb/misc/usbtest.c

···
 		return -ERESTARTSYS;
 
 	/* FIXME: What if a system sleep starts while a test is running? */
-	if (!intf->is_active) {
-		mutex_unlock(&dev->lock);
-		return -EHOSTUNREACH;
-	}
 
 	/* some devices, like ez-usb default devices, need a non-default
 	 * altsetting to have any active endpoints.  some tests change

include/linux/usb.h

···
  *	number from the USB core by calling usb_register_dev().
  * @condition: binding state of the interface: not bound, binding
  *	(in probe()), bound to a driver, or unbinding (in disconnect())
- * @is_active: flag set when the interface is bound and not suspended.
  * @sysfs_files_created: sysfs attributes exist
  * @ep_devs_created: endpoint child pseudo-devices exist
  * @unregistering: flag set when the interface is being unregistered
···
  * @dev: driver model's view of this device
  * @usb_dev: if an interface is bound to the USB major, this will point
  *	to the sysfs representation for that device.
- * @pm_usage_cnt: PM usage counter for this interface; autosuspend is not
- *	allowed unless the counter is 0.
+ * @pm_usage_cnt: PM usage counter for this interface
  * @reset_ws: Used for scheduling resets from atomic context.
  * @reset_running: set to 1 if the interface is currently running a
  *      queued reset so that usb_cancel_queued_reset() doesn't try to
···
 	int minor;			/* minor number this interface is
 					 * bound to */
 	enum usb_interface_condition condition;		/* state of binding */
-	unsigned is_active:1;		/* the interface is not suspended */
 	unsigned sysfs_files_created:1;	/* the sysfs attributes exist */
 	unsigned ep_devs_created:1;	/* endpoint "devices" exist */
 	unsigned unregistering:1;	/* unregistration is in progress */
···
  * @portnum: parent port number (origin 1)
  * @level: number of USB hub ancestors
  * @can_submit: URBs may be submitted
- * @discon_suspended: disconnected while suspended
  * @persist_enabled:  USB_PERSIST enabled for this device
  * @have_langid: whether string_langid is valid
  * @authorized: policy has said we can use it;
···
  * @usbfs_dentry: usbfs dentry entry for the device
  * @maxchild: number of ports if hub
  * @children: child devices - USB devices that are attached to this hub
- * @pm_usage_cnt: usage counter for autosuspend
  * @quirks: quirks of the whole device
  * @urbnum: number of URBs submitted for the whole device
  * @active_duration: total time device is not suspended
- * @autosuspend: for delayed autosuspends
- * @autoresume: for autoresumes requested while in_interrupt
- * @pm_mutex: protects PM operations
  * @last_busy: time of last use
  * @autosuspend_delay: in jiffies
  * @connect_time: time device was first connected
  * @do_remote_wakeup:  remote wakeup should be enabled
  * @reset_resume: needs reset instead of resume
  * @autosuspend_disabled: autosuspend disabled by the user
- * @skip_sys_resume: skip the next system resume
  * @wusb_dev: if this is a Wireless USB device, link to the WUSB
  *	specific data for the device.
  * @slot_id: Slot ID assigned by xHCI
···
 	u8 level;
 
 	unsigned can_submit:1;
-	unsigned discon_suspended:1;
 	unsigned persist_enabled:1;
 	unsigned have_langid:1;
 	unsigned authorized:1;
···
 	int maxchild;
 	struct usb_device *children[USB_MAXCHILDREN];
 
-	int pm_usage_cnt;
 	u32 quirks;
 	atomic_t urbnum;
 
 	unsigned long active_duration;
 
 #ifdef CONFIG_PM
-	struct delayed_work autosuspend;
-	struct work_struct autoresume;
-	struct mutex pm_mutex;
-
 	unsigned long last_busy;
 	int autosuspend_delay;
 	unsigned long connect_time;
···
 	unsigned do_remote_wakeup:1;
 	unsigned reset_resume:1;
 	unsigned autosuspend_disabled:1;
-	unsigned skip_sys_resume:1;
 #endif
 	struct wusb_dev *wusb_dev;
 	int slot_id;
···
 extern void usb_autopm_put_interface(struct usb_interface *intf);
 extern int usb_autopm_get_interface_async(struct usb_interface *intf);
 extern void usb_autopm_put_interface_async(struct usb_interface *intf);
-
-static inline void usb_autopm_get_interface_no_resume(
-		struct usb_interface *intf)
-{
-	atomic_inc(&intf->pm_usage_cnt);
-}
-static inline void usb_autopm_put_interface_no_suspend(
-		struct usb_interface *intf)
-{
-	atomic_dec(&intf->pm_usage_cnt);
-}
+extern void usb_autopm_get_interface_no_resume(struct usb_interface *intf);
+extern void usb_autopm_put_interface_no_suspend(struct usb_interface *intf);
 
 static inline void usb_mark_last_busy(struct usb_device *udev)
 {