diff options
| -rw-r--r-- | Documentation/usb/power-management.txt | 217 | ||||
| -rw-r--r-- | drivers/usb/core/Kconfig | 4 | ||||
| -rw-r--r-- | drivers/usb/core/driver.c | 845 | ||||
| -rw-r--r-- | drivers/usb/core/hcd.c | 13 | ||||
| -rw-r--r-- | drivers/usb/core/hcd.h | 10 | ||||
| -rw-r--r-- | drivers/usb/core/hub.c | 65 | ||||
| -rw-r--r-- | drivers/usb/core/message.c | 1 | ||||
| -rw-r--r-- | drivers/usb/core/usb.c | 35 | ||||
| -rw-r--r-- | drivers/usb/core/usb.h | 49 | ||||
| -rw-r--r-- | drivers/usb/misc/usbtest.c | 4 | ||||
| -rw-r--r-- | include/linux/usb.h | 31 |
11 files changed, 490 insertions, 784 deletions
diff --git a/Documentation/usb/power-management.txt b/Documentation/usb/power-management.txt index e3fa189..2790ad4 100644 --- a/Documentation/usb/power-management.txt +++ b/Documentation/usb/power-management.txt @@ -2,7 +2,7 @@ Alan Stern <stern@rowland.harvard.edu> - November 10, 2009 + December 11, 2009 @@ -29,9 +29,9 @@ covered to some extent (see Documentation/power/*.txt for more 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? @@ -326,64 +326,63 @@ driver does so by calling these six functions: 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.) - -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. - - usb_autopm_get_interface() increments pm_usage_count and - attempts an autoresume if the new value is > 0 and the - device is suspended. - - usb_autopm_put_interface() decrements pm_usage_count and - attempts an autosuspend if the new value is <= 0 and the - device isn't suspended. +This counter is used only by the USB core.) + +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. + +Drivers using the async routines are responsible for their own +synchronization and mutual exclusion. + + 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 @@ -413,26 +412,27 @@ though, setting this flag won't cause the kernel to autoresume it. 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. - -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. +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. + +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 @@ -440,75 +440,23 @@ the PM_EVENT_AUTO bit in the message.event argument to the suspend 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 @@ -517,22 +465,11 @@ synchronize with the driver's I/O activities in some other way. 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 diff --git a/drivers/usb/core/Kconfig b/drivers/usb/core/Kconfig index ad92594..97a819c 100644 --- a/drivers/usb/core/Kconfig +++ b/drivers/usb/core/Kconfig @@ -91,8 +91,8 @@ config USB_DYNAMIC_MINORS 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 diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c index 638d546..6850ec6 100644 --- a/drivers/usb/core/driver.c +++ b/drivers/usb/core/driver.c @@ -25,7 +25,7 @@ #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" @@ -221,7 +221,7 @@ static int usb_probe_device(struct device *dev) { 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__); @@ -230,18 +230,23 @@ static int usb_probe_device(struct device *dev) /* 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; } @@ -293,17 +298,16 @@ static int usb_probe_interface(struct device *dev) 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) { @@ -323,10 +327,14 @@ static int usb_probe_interface(struct device *dev) 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; } @@ -376,9 +384,17 @@ static int usb_unbind_interface(struct device *dev) 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); @@ -409,7 +425,6 @@ int usb_driver_claim_interface(struct usb_driver *driver, 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) @@ -419,11 +434,16 @@ int usb_driver_claim_interface(struct usb_driver *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() @@ -982,7 +1002,6 @@ static void do_unbind_rebind(struct usb_device *udev, int action) } } -/* 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; @@ -1006,7 +1025,6 @@ static int usb_suspend_device(struct usb_device *udev, pm_message_t msg) 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; @@ -1040,27 +1058,20 @@ static int usb_resume_device(struct usb_device *udev, pm_message_t msg) 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 { @@ -1068,7 +1079,6 @@ static int usb_suspend_interface(struct usb_device *udev, intf->needs_binding = 1; dev_warn(&intf->dev, "no %s for driver %s?\n", "suspend", driver->name); - mark_quiesced(intf); } done: @@ -1076,14 +1086,13 @@ static int usb_suspend_interface(struct usb_device *udev, 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 */ @@ -1134,90 +1143,11 @@ static int usb_resume_interface(struct usb_device *udev, 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 * @udev: the usb_device to suspend @@ -1229,27 +1159,12 @@ static inline int autosuspend_check(struct usb_device *udev, int reschedule) * 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. */ @@ -1258,20 +1173,11 @@ static int usb_suspend_both(struct usb_device *udev, pm_message_t msg) 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) { for (; i < udev->actconfig->desc.bNumInterfaces; i++) { @@ -1286,35 +1192,21 @@ static int usb_suspend_both(struct usb_device *udev, pm_message_t msg) /* 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: @@ -1331,23 +1223,12 @@ static int usb_suspend_both(struct usb_device *udev, pm_message_t msg) * 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. */ @@ -1356,48 +1237,18 @@ static int usb_resume_both(struct usb_device *udev, pm_message_t msg) 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]; @@ -1413,104 +1264,46 @@ static int usb_resume_both(struct usb_device *udev, pm_message_t msg) 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; - - udev = to_usb_device(dev); + struct usb_device *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; } @@ -1560,54 +1353,6 @@ int usb_disable_autosuspend(struct usb_device *udev) } 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 @@ -1616,12 +1361,9 @@ void usb_autoresume_work(struct work_struct *work) * @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. * @@ -1631,9 +1373,11 @@ void usb_autosuspend_device(struct usb_device *udev) { 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); } /** @@ -1643,9 +1387,9 @@ void usb_autosuspend_device(struct usb_device *udev) * 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. * @@ -1653,9 +1397,12 @@ void usb_autosuspend_device(struct usb_device *udev) */ 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); } /** @@ -1664,9 +1411,9 @@ void usb_try_autosuspend_device(struct usb_device *udev) * * 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. @@ -1680,42 +1427,14 @@ int usb_autoresume_device(struct usb_device *udev) { 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; } @@ -1729,34 +1448,25 @@ static int usb_autopm_do_interface(struct usb_interface *intf, * 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); @@ -1764,11 +1474,11 @@ 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. @@ -1778,28 +1488,58 @@ EXPORT_SYMBOL_GPL(usb_autopm_put_interface); 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 * @intf: the usb_interface whose counter should be incremented * @@ -1811,25 +1551,8 @@ EXPORT_SYMBOL_GPL(usb_autopm_put_interface_async); * 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. */ @@ -1837,9 +1560,16 @@ int usb_autopm_get_interface(struct usb_interface *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)); + 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); @@ -1849,41 +1579,201 @@ 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); -#else +/** + * 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; -void usb_autosuspend_work(struct work_struct *work) -{} + /* 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_autoresume_work(struct work_struct *work) -{} +#define usb_bus_pm_ops (*(struct dev_pm_ops *) NULL) #endif /* CONFIG_USB_SUSPEND */ @@ -1891,4 +1781,5 @@ struct bus_type usb_bus_type = { .name = "usb", .match = usb_device_match, .uevent = usb_uevent, + .pm = &usb_bus_pm_ops, }; diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c index fc4290b..b07ba05 100644 --- a/drivers/usb/core/hcd.c +++ b/drivers/usb/core/hcd.c @@ -39,6 +39,7 @@ #include <linux/platform_device.h> #include <linux/workqueue.h> #include <linux/mutex.h> +#include <linux/pm_runtime.h> #include <linux/usb.h> @@ -1858,6 +1859,10 @@ int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg) 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) { @@ -1884,12 +1889,12 @@ void usb_hcd_resume_root_hub (struct usb_hcd *hcd) 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 */ /*-------------------------------------------------------------------------*/ @@ -2034,7 +2039,7 @@ struct usb_hcd *usb_create_hcd (const struct hc_driver *driver, 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); @@ -2234,7 +2239,7 @@ void usb_remove_hcd(struct usb_hcd *hcd) 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 diff --git a/drivers/usb/core/hcd.h b/drivers/usb/core/hcd.h index 70a7e49..8953ded 100644 --- a/drivers/usb/core/hcd.h +++ b/drivers/usb/core/hcd.h @@ -80,7 +80,7 @@ struct usb_hcd { 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 @@ -464,16 +464,20 @@ extern int usb_find_interface_driver(struct usb_device *dev, #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 diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index 746f26f..0e0a190 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -22,6 +22,7 @@ #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> @@ -71,7 +72,6 @@ struct usb_hub { unsigned mA_per_port; /* current for each child */ - unsigned init_done:1; unsigned limited_power:1; unsigned quiescing:1; unsigned disconnected:1; @@ -820,7 +820,6 @@ static void hub_activate(struct usb_hub *hub, enum hub_activation_type type) } init3: hub->quiescing = 0; - hub->init_done = 1; status = usb_submit_urb(hub->urb, GFP_NOIO); if (status < 0) @@ -861,11 +860,6 @@ static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type) 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; @@ -1405,10 +1399,8 @@ static void recursively_mark_NOTATTACHED(struct usb_device *udev) 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; } @@ -1532,31 +1524,6 @@ static void update_address(struct usb_device *udev, int devnum) 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 @@ -1625,8 +1592,6 @@ void usb_disconnect(struct usb_device **pdev) *pdev = NULL; spin_unlock_irq(&device_state_lock); - usb_stop_pm(udev); - put_device(&udev->dev); } @@ -1803,9 +1768,6 @@ int usb_new_device(struct usb_device *udev) 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 @@ -1814,6 +1776,10 @@ int usb_new_device(struct usb_device *udev) 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 */ if (err < 0) @@ -1844,7 +1810,8 @@ int usb_new_device(struct usb_device *udev) 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; } @@ -2408,8 +2375,11 @@ int usb_remote_wakeup(struct usb_device *udev) 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; } @@ -2446,11 +2416,6 @@ int usb_port_resume(struct usb_device *udev, pm_message_t msg) return status; } -int usb_remote_wakeup(struct usb_device *udev) -{ - return 0; -} - #endif static int hub_suspend(struct usb_interface *intf, pm_message_t msg) @@ -3268,7 +3233,7 @@ static void hub_events(void) * 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) { @@ -3428,7 +3393,7 @@ static void hub_events(void) * kick_khubd() and allow autosuspend. */ usb_autopm_put_interface(intf); - loop2: + loop_disconnected: usb_unlock_device(hdev); kref_put(&hub->kref, hub_release); diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c index df73574..73de41b 100644 --- a/drivers/usb/core/message.c +++ b/drivers/usb/core/message.c @@ -1843,7 +1843,6 @@ free_interfaces: 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); diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c index 0daff0d..32966cc 100644 --- a/drivers/usb/core/usb.c +++ b/drivers/usb/core/usb.c @@ -49,9 +49,6 @@ const char *usbcore_name = "usbcore"; 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 */ @@ -264,23 +261,6 @@ static int usb_dev_uevent(struct device *dev, struct kobj_uevent_env *env) #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 @@ -296,7 +276,7 @@ static int usb_dev_prepare(struct device *dev) 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) @@ -342,9 +322,7 @@ static const struct dev_pm_ops usb_device_pm_ops = { #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 */ @@ -472,9 +450,6 @@ struct usb_device *usb_alloc_dev(struct usb_device *parent, 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; @@ -1117,9 +1092,6 @@ static int __init usb_init(void) if (retval) goto out; - retval = ksuspend_usb_init(); - if (retval) - goto out; retval = bus_register(&usb_bus_type); if (retval) goto bus_register_failed; @@ -1159,7 +1131,7 @@ major_init_failed: bus_notifier_failed: bus_unregister(&usb_bus_type); bus_register_failed: - ksuspend_usb_cleanup(); + usb_debugfs_cleanup(); out: return retval; } @@ -1181,7 +1153,6 @@ static void __exit usb_exit(void) usb_hub_cleanup(); bus_unregister_notifier(&usb_bus_type, &usb_bus_nb); bus_unregister(&usb_bus_type); - ksuspend_usb_cleanup(); usb_debugfs_cleanup(); } diff --git a/drivers/usb/core/usb.h b/drivers/usb/core/usb.h index 2b74a7f..cd88220 100644 --- a/drivers/usb/core/usb.h +++ b/drivers/usb/core/usb.h @@ -55,25 +55,8 @@ extern void usb_major_cleanup(void); 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 @@ -87,14 +70,6 @@ static inline int usb_port_resume(struct usb_device *udev, pm_message_t msg) 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 @@ -102,6 +77,7 @@ static inline void usb_pm_unlock(struct usb_device *udev) {} 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 @@ -112,9 +88,13 @@ static inline int usb_autoresume_device(struct usb_device *udev) 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; @@ -144,23 +124,6 @@ static inline int is_usb_device_driver(struct device_driver *drv) 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; -} - /* for labeling diagnostics */ extern const char *usbcore_name; diff --git a/drivers/usb/misc/usbtest.c b/drivers/usb/misc/usbtest.c index 3dab0c0..707a87d 100644 --- a/drivers/usb/misc/usbtest.c +++ b/drivers/usb/misc/usbtest.c @@ -1580,10 +1580,6 @@ usbtest_ioctl (struct usb_interface *intf, unsigned int code, void *buf) 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 diff --git a/include/linux/usb.h b/include/linux/usb.h index e6419ac..ad50fc8 100644 --- a/include/linux/usb.h +++ b/include/linux/usb.h @@ -122,7 +122,6 @@ enum usb_interface_condition { * 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 @@ -135,8 +134,7 @@ enum usb_interface_condition { * @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 @@ -184,7 +182,6 @@ struct usb_interface { 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 */ @@ -401,7 +398,6 @@ struct usb_tt; * @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; @@ -421,20 +417,15 @@ struct usb_tt; * @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 @@ -475,7 +466,6 @@ struct usb_device { u8 level; unsigned can_submit:1; - unsigned discon_suspended:1; unsigned persist_enabled:1; unsigned have_langid:1; unsigned authorized:1; @@ -499,17 +489,12 @@ struct usb_device { 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; @@ -517,7 +502,6 @@ struct usb_device { 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; @@ -549,17 +533,8 @@ extern int usb_autopm_get_interface(struct usb_interface *intf); 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) { |
