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-rw-r--r--Documentation/power/devices.txt67
-rw-r--r--Documentation/power/runtime_pm.txt5
-rw-r--r--drivers/base/power/clock_ops.c4
-rw-r--r--drivers/base/power/main.c28
-rw-r--r--drivers/pci/pci-driver.c4
-rw-r--r--drivers/usb/core/driver.c6
-rw-r--r--include/linux/device.h4
-rw-r--r--include/linux/pm.h3
-rw-r--r--kernel/power/user.c4
9 files changed, 50 insertions, 75 deletions
diff --git a/Documentation/power/devices.txt b/Documentation/power/devices.txt
index 88880839ece4..64565aac6e40 100644
--- a/Documentation/power/devices.txt
+++ b/Documentation/power/devices.txt
@@ -520,59 +520,20 @@ Support for power domains is provided through the pwr_domain field of struct
520device. This field is a pointer to an object of type struct dev_power_domain, 520device. This field is a pointer to an object of type struct dev_power_domain,
521defined in include/linux/pm.h, providing a set of power management callbacks 521defined in include/linux/pm.h, providing a set of power management callbacks
522analogous to the subsystem-level and device driver callbacks that are executed 522analogous to the subsystem-level and device driver callbacks that are executed
523for the given device during all power transitions, in addition to the respective 523for the given device during all power transitions, instead of the respective
524subsystem-level callbacks. Specifically, the power domain "suspend" callbacks 524subsystem-level callbacks. Specifically, if a device's pm_domain pointer is
525(i.e. ->runtime_suspend(), ->suspend(), ->freeze(), ->poweroff(), etc.) are 525not NULL, the ->suspend() callback from the object pointed to by it will be
526executed after the analogous subsystem-level callbacks, while the power domain 526executed instead of its subsystem's (e.g. bus type's) ->suspend() callback and
527"resume" callbacks (i.e. ->runtime_resume(), ->resume(), ->thaw(), ->restore, 527anlogously for all of the remaining callbacks. In other words, power management
528etc.) are executed before the analogous subsystem-level callbacks. Error codes 528domain callbacks, if defined for the given device, always take precedence over
529returned by the "suspend" and "resume" power domain callbacks are ignored. 529the callbacks provided by the device's subsystem (e.g. bus type).
530 530
531Power domain ->runtime_idle() callback is executed before the subsystem-level 531The support for device power management domains is only relevant to platforms
532->runtime_idle() callback and the result returned by it is not ignored. Namely, 532needing to use the same device driver power management callbacks in many
533if it returns error code, the subsystem-level ->runtime_idle() callback will not 533different power domain configurations and wanting to avoid incorporating the
534be called and the helper function rpm_idle() executing it will return error 534support for power domains into subsystem-level callbacks, for example by
535code. This mechanism is intended to help platforms where saving device state 535modifying the platform bus type. Other platforms need not implement it or take
536is a time consuming operation and should only be carried out if all devices 536it into account in any way.
537in the power domain are idle, before turning off the shared power resource(s).
538Namely, the power domain ->runtime_idle() callback may return error code until
539the pm_runtime_idle() helper (or its asychronous version) has been called for
540all devices in the power domain (it is recommended that the returned error code
541be -EBUSY in those cases), preventing the subsystem-level ->runtime_idle()
542callback from being run prematurely.
543
544The support for device power domains is only relevant to platforms needing to
545use the same subsystem-level (e.g. platform bus type) and device driver power
546management callbacks in many different power domain configurations and wanting
547to avoid incorporating the support for power domains into the subsystem-level
548callbacks. The other platforms need not implement it or take it into account
549in any way.
550
551
552System Devices
553--------------
554System devices (sysdevs) follow a slightly different API, which can be found in
555
556 include/linux/sysdev.h
557 drivers/base/sys.c
558
559System devices will be suspended with interrupts disabled, and after all other
560devices have been suspended. On resume, they will be resumed before any other
561devices, and also with interrupts disabled. These things occur in special
562"sysdev_driver" phases, which affect only system devices.
563
564Thus, after the suspend_noirq (or freeze_noirq or poweroff_noirq) phase, when
565the non-boot CPUs are all offline and IRQs are disabled on the remaining online
566CPU, then a sysdev_driver.suspend phase is carried out, and the system enters a
567sleep state (or a system image is created). During resume (or after the image
568has been created or loaded) a sysdev_driver.resume phase is carried out, IRQs
569are enabled on the only online CPU, the non-boot CPUs are enabled, and the
570resume_noirq (or thaw_noirq or restore_noirq) phase begins.
571
572Code to actually enter and exit the system-wide low power state sometimes
573involves hardware details that are only known to the boot firmware, and
574may leave a CPU running software (from SRAM or flash memory) that monitors
575the system and manages its wakeup sequence.
576 537
577 538
578Device Low Power (suspend) States 539Device Low Power (suspend) States
diff --git a/Documentation/power/runtime_pm.txt b/Documentation/power/runtime_pm.txt
index 654097b130b4..22accb3eb40e 100644
--- a/Documentation/power/runtime_pm.txt
+++ b/Documentation/power/runtime_pm.txt
@@ -566,11 +566,6 @@ to do this is:
566 pm_runtime_set_active(dev); 566 pm_runtime_set_active(dev);
567 pm_runtime_enable(dev); 567 pm_runtime_enable(dev);
568 568
569The PM core always increments the run-time usage counter before calling the
570->prepare() callback and decrements it after calling the ->complete() callback.
571Hence disabling run-time PM temporarily like this will not cause any run-time
572suspend callbacks to be lost.
573
5747. Generic subsystem callbacks 5697. Generic subsystem callbacks
575 570
576Subsystems may wish to conserve code space by using the set of generic power 571Subsystems may wish to conserve code space by using the set of generic power
diff --git a/drivers/base/power/clock_ops.c b/drivers/base/power/clock_ops.c
index eaa8a854af03..ad367c4139b1 100644
--- a/drivers/base/power/clock_ops.c
+++ b/drivers/base/power/clock_ops.c
@@ -387,7 +387,7 @@ static int pm_runtime_clk_notify(struct notifier_block *nb,
387 clknb = container_of(nb, struct pm_clk_notifier_block, nb); 387 clknb = container_of(nb, struct pm_clk_notifier_block, nb);
388 388
389 switch (action) { 389 switch (action) {
390 case BUS_NOTIFY_ADD_DEVICE: 390 case BUS_NOTIFY_BIND_DRIVER:
391 if (clknb->con_ids[0]) { 391 if (clknb->con_ids[0]) {
392 for (con_id = clknb->con_ids; *con_id; con_id++) 392 for (con_id = clknb->con_ids; *con_id; con_id++)
393 enable_clock(dev, *con_id); 393 enable_clock(dev, *con_id);
@@ -395,7 +395,7 @@ static int pm_runtime_clk_notify(struct notifier_block *nb,
395 enable_clock(dev, NULL); 395 enable_clock(dev, NULL);
396 } 396 }
397 break; 397 break;
398 case BUS_NOTIFY_DEL_DEVICE: 398 case BUS_NOTIFY_UNBOUND_DRIVER:
399 if (clknb->con_ids[0]) { 399 if (clknb->con_ids[0]) {
400 for (con_id = clknb->con_ids; *con_id; con_id++) 400 for (con_id = clknb->con_ids; *con_id; con_id++)
401 disable_clock(dev, *con_id); 401 disable_clock(dev, *con_id);
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
index aa6320207745..06f09bf89cb2 100644
--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -57,7 +57,8 @@ static int async_error;
57 */ 57 */
58void device_pm_init(struct device *dev) 58void device_pm_init(struct device *dev)
59{ 59{
60 dev->power.in_suspend = false; 60 dev->power.is_prepared = false;
61 dev->power.is_suspended = false;
61 init_completion(&dev->power.completion); 62 init_completion(&dev->power.completion);
62 complete_all(&dev->power.completion); 63 complete_all(&dev->power.completion);
63 dev->power.wakeup = NULL; 64 dev->power.wakeup = NULL;
@@ -91,7 +92,7 @@ void device_pm_add(struct device *dev)
91 pr_debug("PM: Adding info for %s:%s\n", 92 pr_debug("PM: Adding info for %s:%s\n",
92 dev->bus ? dev->bus->name : "No Bus", dev_name(dev)); 93 dev->bus ? dev->bus->name : "No Bus", dev_name(dev));
93 mutex_lock(&dpm_list_mtx); 94 mutex_lock(&dpm_list_mtx);
94 if (dev->parent && dev->parent->power.in_suspend) 95 if (dev->parent && dev->parent->power.is_prepared)
95 dev_warn(dev, "parent %s should not be sleeping\n", 96 dev_warn(dev, "parent %s should not be sleeping\n",
96 dev_name(dev->parent)); 97 dev_name(dev->parent));
97 list_add_tail(&dev->power.entry, &dpm_list); 98 list_add_tail(&dev->power.entry, &dpm_list);
@@ -511,7 +512,14 @@ static int device_resume(struct device *dev, pm_message_t state, bool async)
511 dpm_wait(dev->parent, async); 512 dpm_wait(dev->parent, async);
512 device_lock(dev); 513 device_lock(dev);
513 514
514 dev->power.in_suspend = false; 515 /*
516 * This is a fib. But we'll allow new children to be added below
517 * a resumed device, even if the device hasn't been completed yet.
518 */
519 dev->power.is_prepared = false;
520
521 if (!dev->power.is_suspended)
522 goto Unlock;
515 523
516 if (dev->pwr_domain) { 524 if (dev->pwr_domain) {
517 pm_dev_dbg(dev, state, "power domain "); 525 pm_dev_dbg(dev, state, "power domain ");
@@ -548,6 +556,9 @@ static int device_resume(struct device *dev, pm_message_t state, bool async)
548 } 556 }
549 557
550 End: 558 End:
559 dev->power.is_suspended = false;
560
561 Unlock:
551 device_unlock(dev); 562 device_unlock(dev);
552 complete_all(&dev->power.completion); 563 complete_all(&dev->power.completion);
553 564
@@ -670,7 +681,7 @@ void dpm_complete(pm_message_t state)
670 struct device *dev = to_device(dpm_prepared_list.prev); 681 struct device *dev = to_device(dpm_prepared_list.prev);
671 682
672 get_device(dev); 683 get_device(dev);
673 dev->power.in_suspend = false; 684 dev->power.is_prepared = false;
674 list_move(&dev->power.entry, &list); 685 list_move(&dev->power.entry, &list);
675 mutex_unlock(&dpm_list_mtx); 686 mutex_unlock(&dpm_list_mtx);
676 687
@@ -835,11 +846,11 @@ static int __device_suspend(struct device *dev, pm_message_t state, bool async)
835 device_lock(dev); 846 device_lock(dev);
836 847
837 if (async_error) 848 if (async_error)
838 goto End; 849 goto Unlock;
839 850
840 if (pm_wakeup_pending()) { 851 if (pm_wakeup_pending()) {
841 async_error = -EBUSY; 852 async_error = -EBUSY;
842 goto End; 853 goto Unlock;
843 } 854 }
844 855
845 if (dev->pwr_domain) { 856 if (dev->pwr_domain) {
@@ -877,6 +888,9 @@ static int __device_suspend(struct device *dev, pm_message_t state, bool async)
877 } 888 }
878 889
879 End: 890 End:
891 dev->power.is_suspended = !error;
892
893 Unlock:
880 device_unlock(dev); 894 device_unlock(dev);
881 complete_all(&dev->power.completion); 895 complete_all(&dev->power.completion);
882 896
@@ -1042,7 +1056,7 @@ int dpm_prepare(pm_message_t state)
1042 put_device(dev); 1056 put_device(dev);
1043 break; 1057 break;
1044 } 1058 }
1045 dev->power.in_suspend = true; 1059 dev->power.is_prepared = true;
1046 if (!list_empty(&dev->power.entry)) 1060 if (!list_empty(&dev->power.entry))
1047 list_move_tail(&dev->power.entry, &dpm_prepared_list); 1061 list_move_tail(&dev->power.entry, &dpm_prepared_list);
1048 put_device(dev); 1062 put_device(dev);
diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
index 135df164a4c1..46767c53917a 100644
--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c
@@ -624,7 +624,7 @@ static int pci_pm_prepare(struct device *dev)
624 * system from the sleep state, we'll have to prevent it from signaling 624 * system from the sleep state, we'll have to prevent it from signaling
625 * wake-up. 625 * wake-up.
626 */ 626 */
627 pm_runtime_resume(dev); 627 pm_runtime_get_sync(dev);
628 628
629 if (drv && drv->pm && drv->pm->prepare) 629 if (drv && drv->pm && drv->pm->prepare)
630 error = drv->pm->prepare(dev); 630 error = drv->pm->prepare(dev);
@@ -638,6 +638,8 @@ static void pci_pm_complete(struct device *dev)
638 638
639 if (drv && drv->pm && drv->pm->complete) 639 if (drv && drv->pm && drv->pm->complete)
640 drv->pm->complete(dev); 640 drv->pm->complete(dev);
641
642 pm_runtime_put_sync(dev);
641} 643}
642 644
643#else /* !CONFIG_PM_SLEEP */ 645#else /* !CONFIG_PM_SLEEP */
diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
index e35a17687c05..aa3cc465a601 100644
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -375,7 +375,7 @@ static int usb_unbind_interface(struct device *dev)
375 * Just re-enable it without affecting the endpoint toggles. 375 * Just re-enable it without affecting the endpoint toggles.
376 */ 376 */
377 usb_enable_interface(udev, intf, false); 377 usb_enable_interface(udev, intf, false);
378 } else if (!error && !intf->dev.power.in_suspend) { 378 } else if (!error && !intf->dev.power.is_prepared) {
379 r = usb_set_interface(udev, intf->altsetting[0]. 379 r = usb_set_interface(udev, intf->altsetting[0].
380 desc.bInterfaceNumber, 0); 380 desc.bInterfaceNumber, 0);
381 if (r < 0) 381 if (r < 0)
@@ -960,7 +960,7 @@ void usb_rebind_intf(struct usb_interface *intf)
960 } 960 }
961 961
962 /* Try to rebind the interface */ 962 /* Try to rebind the interface */
963 if (!intf->dev.power.in_suspend) { 963 if (!intf->dev.power.is_prepared) {
964 intf->needs_binding = 0; 964 intf->needs_binding = 0;
965 rc = device_attach(&intf->dev); 965 rc = device_attach(&intf->dev);
966 if (rc < 0) 966 if (rc < 0)
@@ -1107,7 +1107,7 @@ static int usb_resume_interface(struct usb_device *udev,
1107 if (intf->condition == USB_INTERFACE_UNBOUND) { 1107 if (intf->condition == USB_INTERFACE_UNBOUND) {
1108 1108
1109 /* Carry out a deferred switch to altsetting 0 */ 1109 /* Carry out a deferred switch to altsetting 0 */
1110 if (intf->needs_altsetting0 && !intf->dev.power.in_suspend) { 1110 if (intf->needs_altsetting0 && !intf->dev.power.is_prepared) {
1111 usb_set_interface(udev, intf->altsetting[0]. 1111 usb_set_interface(udev, intf->altsetting[0].
1112 desc.bInterfaceNumber, 0); 1112 desc.bInterfaceNumber, 0);
1113 intf->needs_altsetting0 = 0; 1113 intf->needs_altsetting0 = 0;
diff --git a/include/linux/device.h b/include/linux/device.h
index c66111affca9..553fd37b173b 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -654,13 +654,13 @@ static inline int device_is_registered(struct device *dev)
654 654
655static inline void device_enable_async_suspend(struct device *dev) 655static inline void device_enable_async_suspend(struct device *dev)
656{ 656{
657 if (!dev->power.in_suspend) 657 if (!dev->power.is_prepared)
658 dev->power.async_suspend = true; 658 dev->power.async_suspend = true;
659} 659}
660 660
661static inline void device_disable_async_suspend(struct device *dev) 661static inline void device_disable_async_suspend(struct device *dev)
662{ 662{
663 if (!dev->power.in_suspend) 663 if (!dev->power.is_prepared)
664 dev->power.async_suspend = false; 664 dev->power.async_suspend = false;
665} 665}
666 666
diff --git a/include/linux/pm.h b/include/linux/pm.h
index 3160648ccdda..411e4f4be52b 100644
--- a/include/linux/pm.h
+++ b/include/linux/pm.h
@@ -425,7 +425,8 @@ struct dev_pm_info {
425 pm_message_t power_state; 425 pm_message_t power_state;
426 unsigned int can_wakeup:1; 426 unsigned int can_wakeup:1;
427 unsigned int async_suspend:1; 427 unsigned int async_suspend:1;
428 unsigned int in_suspend:1; /* Owned by the PM core */ 428 bool is_prepared:1; /* Owned by the PM core */
429 bool is_suspended:1; /* Ditto */
429 spinlock_t lock; 430 spinlock_t lock;
430#ifdef CONFIG_PM_SLEEP 431#ifdef CONFIG_PM_SLEEP
431 struct list_head entry; 432 struct list_head entry;
diff --git a/kernel/power/user.c b/kernel/power/user.c
index 7d02d33be699..42ddbc6f0de6 100644
--- a/kernel/power/user.c
+++ b/kernel/power/user.c
@@ -113,8 +113,10 @@ static int snapshot_open(struct inode *inode, struct file *filp)
113 if (error) 113 if (error)
114 pm_notifier_call_chain(PM_POST_RESTORE); 114 pm_notifier_call_chain(PM_POST_RESTORE);
115 } 115 }
116 if (error) 116 if (error) {
117 free_basic_memory_bitmaps();
117 atomic_inc(&snapshot_device_available); 118 atomic_inc(&snapshot_device_available);
119 }
118 data->frozen = 0; 120 data->frozen = 0;
119 data->ready = 0; 121 data->ready = 0;
120 data->platform_support = 0; 122 data->platform_support = 0;