diff --git a/Documentation/power/pci.txt b/Documentation/power/pci.txt index ab4e7d0540c1..304162ea377e 100644 --- a/Documentation/power/pci.txt +++ b/Documentation/power/pci.txt @@ -980,6 +980,20 @@ positive value from pci_pm_prepare() if the ->prepare callback provided by the driver of the device returns a positive value. That allows the driver to opt out from using the direct-complete mechanism dynamically. +The DPM_FLAG_SMART_SUSPEND flag tells the PCI bus type that from the driver's +perspective the device can be safely left in runtime suspend during system +suspend. That causes pci_pm_suspend(), pci_pm_freeze() and pci_pm_poweroff() +to skip resuming the device from runtime suspend unless there are PCI-specific +reasons for doing that. Also, it causes pci_pm_suspend_late/noirq(), +pci_pm_freeze_late/noirq() and pci_pm_poweroff_late/noirq() to return early +if the device remains in runtime suspend in the beginning of the "late" phase +of the system-wide transition under way. Moreover, if the device is in +runtime suspend in pci_pm_resume_noirq() or pci_pm_restore_noirq(), its runtime +power management status will be changed to "active" (as it is going to be put +into D0 going forward), but if it is in runtime suspend in pci_pm_thaw_noirq(), +the function will set the power.direct_complete flag for it (to make the PM core +skip the subsequent "thaw" callbacks for it) and return. + 3.2. Device Runtime Power Management ------------------------------------ In addition to providing device power management callbacks PCI device drivers diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index 8d9024017645..6c6f1c74c24c 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -1861,3 +1861,9 @@ void device_pm_check_callbacks(struct device *dev) !dev->driver->suspend && !dev->driver->resume)); spin_unlock_irq(&dev->power.lock); } + +bool dev_pm_smart_suspend_and_suspended(struct device *dev) +{ + return dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) && + pm_runtime_status_suspended(dev); +} diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c index c1aeeb10539e..d19bd54d337e 100644 --- a/drivers/pci/pci-driver.c +++ b/drivers/pci/pci-driver.c @@ -734,18 +734,25 @@ static int pci_pm_suspend(struct device *dev) if (!pm) { pci_pm_default_suspend(pci_dev); - goto Fixup; + return 0; } /* - * PCI devices suspended at run time need to be resumed at this point, - * because in general it is necessary to reconfigure them for system - * suspend. Namely, if the device is supposed to wake up the system - * from the sleep state, we may need to reconfigure it for this purpose. - * In turn, if the device is not supposed to wake up the system from the - * sleep state, we'll have to prevent it from signaling wake-up. + * PCI devices suspended at run time may need to be resumed at this + * point, because in general it may be necessary to reconfigure them for + * system suspend. Namely, if the device is expected to wake up the + * system from the sleep state, it may have to be reconfigured for this + * purpose, or if the device is not expected to wake up the system from + * the sleep state, it should be prevented from signaling wakeup events + * going forward. + * + * Also if the driver of the device does not indicate that its system + * suspend callbacks can cope with runtime-suspended devices, it is + * better to resume the device from runtime suspend here. */ - pm_runtime_resume(dev); + if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) || + !pci_dev_keep_suspended(pci_dev)) + pm_runtime_resume(dev); pci_dev->state_saved = false; if (pm->suspend) { @@ -765,17 +772,27 @@ static int pci_pm_suspend(struct device *dev) } } - Fixup: - pci_fixup_device(pci_fixup_suspend, pci_dev); - return 0; } +static int pci_pm_suspend_late(struct device *dev) +{ + if (dev_pm_smart_suspend_and_suspended(dev)) + return 0; + + pci_fixup_device(pci_fixup_suspend, to_pci_dev(dev)); + + return pm_generic_suspend_late(dev); +} + static int pci_pm_suspend_noirq(struct device *dev) { struct pci_dev *pci_dev = to_pci_dev(dev); const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + if (dev_pm_smart_suspend_and_suspended(dev)) + return 0; + if (pci_has_legacy_pm_support(pci_dev)) return pci_legacy_suspend_late(dev, PMSG_SUSPEND); @@ -834,6 +851,14 @@ static int pci_pm_resume_noirq(struct device *dev) struct device_driver *drv = dev->driver; int error = 0; + /* + * Devices with DPM_FLAG_SMART_SUSPEND may be left in runtime suspend + * during system suspend, so update their runtime PM status to "active" + * as they are going to be put into D0 shortly. + */ + if (dev_pm_smart_suspend_and_suspended(dev)) + pm_runtime_set_active(dev); + pci_pm_default_resume_early(pci_dev); if (pci_has_legacy_pm_support(pci_dev)) @@ -876,6 +901,7 @@ static int pci_pm_resume(struct device *dev) #else /* !CONFIG_SUSPEND */ #define pci_pm_suspend NULL +#define pci_pm_suspend_late NULL #define pci_pm_suspend_noirq NULL #define pci_pm_resume NULL #define pci_pm_resume_noirq NULL @@ -910,7 +936,8 @@ static int pci_pm_freeze(struct device *dev) * devices should not be touched during freeze/thaw transitions, * however. */ - pm_runtime_resume(dev); + if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND)) + pm_runtime_resume(dev); pci_dev->state_saved = false; if (pm->freeze) { @@ -925,11 +952,22 @@ static int pci_pm_freeze(struct device *dev) return 0; } +static int pci_pm_freeze_late(struct device *dev) +{ + if (dev_pm_smart_suspend_and_suspended(dev)) + return 0; + + return pm_generic_freeze_late(dev);; +} + static int pci_pm_freeze_noirq(struct device *dev) { struct pci_dev *pci_dev = to_pci_dev(dev); struct device_driver *drv = dev->driver; + if (dev_pm_smart_suspend_and_suspended(dev)) + return 0; + if (pci_has_legacy_pm_support(pci_dev)) return pci_legacy_suspend_late(dev, PMSG_FREEZE); @@ -959,6 +997,16 @@ static int pci_pm_thaw_noirq(struct device *dev) struct device_driver *drv = dev->driver; int error = 0; + /* + * If the device is in runtime suspend, the code below may not work + * correctly with it, so skip that code and make the PM core skip all of + * the subsequent "thaw" callbacks for the device. + */ + if (dev_pm_smart_suspend_and_suspended(dev)) { + dev->power.direct_complete = true; + return 0; + } + if (pcibios_pm_ops.thaw_noirq) { error = pcibios_pm_ops.thaw_noirq(dev); if (error) @@ -1008,11 +1056,13 @@ static int pci_pm_poweroff(struct device *dev) if (!pm) { pci_pm_default_suspend(pci_dev); - goto Fixup; + return 0; } /* The reason to do that is the same as in pci_pm_suspend(). */ - pm_runtime_resume(dev); + if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) || + !pci_dev_keep_suspended(pci_dev)) + pm_runtime_resume(dev); pci_dev->state_saved = false; if (pm->poweroff) { @@ -1024,17 +1074,27 @@ static int pci_pm_poweroff(struct device *dev) return error; } - Fixup: - pci_fixup_device(pci_fixup_suspend, pci_dev); - return 0; } +static int pci_pm_poweroff_late(struct device *dev) +{ + if (dev_pm_smart_suspend_and_suspended(dev)) + return 0; + + pci_fixup_device(pci_fixup_suspend, to_pci_dev(dev)); + + return pm_generic_poweroff_late(dev); +} + static int pci_pm_poweroff_noirq(struct device *dev) { struct pci_dev *pci_dev = to_pci_dev(dev); struct device_driver *drv = dev->driver; + if (dev_pm_smart_suspend_and_suspended(dev)) + return 0; + if (pci_has_legacy_pm_support(to_pci_dev(dev))) return pci_legacy_suspend_late(dev, PMSG_HIBERNATE); @@ -1076,6 +1136,10 @@ static int pci_pm_restore_noirq(struct device *dev) struct device_driver *drv = dev->driver; int error = 0; + /* This is analogous to the pci_pm_resume_noirq() case. */ + if (dev_pm_smart_suspend_and_suspended(dev)) + pm_runtime_set_active(dev); + if (pcibios_pm_ops.restore_noirq) { error = pcibios_pm_ops.restore_noirq(dev); if (error) @@ -1124,10 +1188,12 @@ static int pci_pm_restore(struct device *dev) #else /* !CONFIG_HIBERNATE_CALLBACKS */ #define pci_pm_freeze NULL +#define pci_pm_freeze_late NULL #define pci_pm_freeze_noirq NULL #define pci_pm_thaw NULL #define pci_pm_thaw_noirq NULL #define pci_pm_poweroff NULL +#define pci_pm_poweroff_late NULL #define pci_pm_poweroff_noirq NULL #define pci_pm_restore NULL #define pci_pm_restore_noirq NULL @@ -1243,10 +1309,13 @@ static const struct dev_pm_ops pci_dev_pm_ops = { .prepare = pci_pm_prepare, .complete = pci_pm_complete, .suspend = pci_pm_suspend, + .suspend_late = pci_pm_suspend_late, .resume = pci_pm_resume, .freeze = pci_pm_freeze, + .freeze_late = pci_pm_freeze_late, .thaw = pci_pm_thaw, .poweroff = pci_pm_poweroff, + .poweroff_late = pci_pm_poweroff_late, .restore = pci_pm_restore, .suspend_noirq = pci_pm_suspend_noirq, .resume_noirq = pci_pm_resume_noirq, diff --git a/include/linux/pm.h b/include/linux/pm.h index 43b5418e05bb..65d39115f06d 100644 --- a/include/linux/pm.h +++ b/include/linux/pm.h @@ -765,6 +765,8 @@ extern int pm_generic_poweroff_late(struct device *dev); extern int pm_generic_poweroff(struct device *dev); extern void pm_generic_complete(struct device *dev); +extern bool dev_pm_smart_suspend_and_suspended(struct device *dev); + #else /* !CONFIG_PM_SLEEP */ #define device_pm_lock() do {} while (0)