From a380f2edef65b2447a043251bb3c00a9d2153a8b Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Mon, 25 Sep 2017 14:56:44 +0200 Subject: PM / core: Drop legacy class suspend/resume operations There are no classes using the legacy suspend/resume operations in the tree any more, so drop these operations and update the code referring to them accordingly. Signed-off-by: Rafael J. Wysocki Acked-by: Greg Kroah-Hartman --- include/linux/device.h | 5 ----- 1 file changed, 5 deletions(-) (limited to 'include') diff --git a/include/linux/device.h b/include/linux/device.h index 1d2607923a24..c1527f887050 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -372,9 +372,6 @@ int subsys_virtual_register(struct bus_type *subsys, * @devnode: Callback to provide the devtmpfs. * @class_release: Called to release this class. * @dev_release: Called to release the device. - * @suspend: Used to put the device to sleep mode, usually to a low power - * state. - * @resume: Used to bring the device from the sleep mode. * @shutdown_pre: Called at shut-down time before driver shutdown. * @ns_type: Callbacks so sysfs can detemine namespaces. * @namespace: Namespace of the device belongs to this class. @@ -402,8 +399,6 @@ struct class { void (*class_release)(struct class *class); void (*dev_release)(struct device *dev); - int (*suspend)(struct device *dev, pm_message_t state); - int (*resume)(struct device *dev); int (*shutdown_pre)(struct device *dev); const struct kobj_ns_type_operations *ns_type; -- cgit v1.2.3 From 08810a4119aaebf6318f209ec5dd9828e969cba4 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 25 Oct 2017 14:12:29 +0200 Subject: PM / core: Add NEVER_SKIP and SMART_PREPARE driver flags The motivation for this change is to provide a way to work around a problem with the direct-complete mechanism used for avoiding system suspend/resume handling for devices in runtime suspend. The problem is that some middle layer code (the PCI bus type and the ACPI PM domain in particular) returns positive values from its system suspend ->prepare callbacks regardless of whether the driver's ->prepare returns a positive value or 0, which effectively prevents drivers from being able to control the direct-complete feature. Some drivers need that control, however, and the PCI bus type has grown its own flag to deal with this issue, but since it is not limited to PCI, it is better to address it by adding driver flags at the core level. To that end, add a driver_flags field to struct dev_pm_info for flags that can be set by device drivers at the probe time to inform the PM core and/or bus types, PM domains and so on on the capabilities and/or preferences of device drivers. Also add two static inline helpers for setting that field and testing it against a given set of flags and make the driver core clear it automatically on driver remove and probe failures. Define and document two PM driver flags related to the direct- complete feature: NEVER_SKIP and SMART_PREPARE that can be used, respectively, to indicate to the PM core that the direct-complete mechanism should never be used for the device and to inform the middle layer code (bus types, PM domains etc) that it can only request the PM core to use the direct-complete mechanism for the device (by returning a positive value from its ->prepare callback) if it also has been requested by the driver. While at it, make the core check pm_runtime_suspended() when setting power.direct_complete so that it doesn't need to be checked by ->prepare callbacks. Signed-off-by: Rafael J. Wysocki Acked-by: Greg Kroah-Hartman Acked-by: Bjorn Helgaas Reviewed-by: Ulf Hansson --- Documentation/driver-api/pm/devices.rst | 14 ++++++++++++++ Documentation/power/pci.txt | 19 +++++++++++++++++++ drivers/acpi/device_pm.c | 13 +++++++++---- drivers/base/dd.c | 2 ++ drivers/base/power/main.c | 4 +++- drivers/pci/pci-driver.c | 5 ++++- include/linux/device.h | 10 ++++++++++ include/linux/pm.h | 20 ++++++++++++++++++++ 8 files changed, 81 insertions(+), 6 deletions(-) (limited to 'include') diff --git a/Documentation/driver-api/pm/devices.rst b/Documentation/driver-api/pm/devices.rst index 4a18ef9997c0..8add5b302a89 100644 --- a/Documentation/driver-api/pm/devices.rst +++ b/Documentation/driver-api/pm/devices.rst @@ -354,6 +354,20 @@ the phases are: ``prepare``, ``suspend``, ``suspend_late``, ``suspend_noirq``. is because all such devices are initially set to runtime-suspended with runtime PM disabled. + This feature also can be controlled by device drivers by using the + ``DPM_FLAG_NEVER_SKIP`` and ``DPM_FLAG_SMART_PREPARE`` driver power + management flags. [Typically, they are set at the time the driver is + probed against the device in question by passing them to the + :c:func:`dev_pm_set_driver_flags` helper function.] If the first of + these flags is set, the PM core will not apply the direct-complete + procedure described above to the given device and, consequenty, to any + of its ancestors. The second flag, when set, informs the middle layer + code (bus types, device types, PM domains, classes) that it should take + the return value of the ``->prepare`` callback provided by the driver + into account and it may only return a positive value from its own + ``->prepare`` callback if the driver's one also has returned a positive + value. + 2. The ``->suspend`` methods should quiesce the device to stop it from performing I/O. They also may save the device registers and put it into the appropriate low-power state, depending on the bus type the device is diff --git a/Documentation/power/pci.txt b/Documentation/power/pci.txt index a1b7f7158930..ab4e7d0540c1 100644 --- a/Documentation/power/pci.txt +++ b/Documentation/power/pci.txt @@ -961,6 +961,25 @@ dev_pm_ops to indicate that one suspend routine is to be pointed to by the .suspend(), .freeze(), and .poweroff() members and one resume routine is to be pointed to by the .resume(), .thaw(), and .restore() members. +3.1.19. Driver Flags for Power Management + +The PM core allows device drivers to set flags that influence the handling of +power management for the devices by the core itself and by middle layer code +including the PCI bus type. The flags should be set once at the driver probe +time with the help of the dev_pm_set_driver_flags() function and they should not +be updated directly afterwards. + +The DPM_FLAG_NEVER_SKIP flag prevents the PM core from using the direct-complete +mechanism allowing device suspend/resume callbacks to be skipped if the device +is in runtime suspend when the system suspend starts. That also affects all of +the ancestors of the device, so this flag should only be used if absolutely +necessary. + +The DPM_FLAG_SMART_PREPARE flag instructs the PCI bus type to only return a +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. + 3.2. Device Runtime Power Management ------------------------------------ In addition to providing device power management callbacks PCI device drivers diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c index 17e8eb93a76c..b4dcc6144e6b 100644 --- a/drivers/acpi/device_pm.c +++ b/drivers/acpi/device_pm.c @@ -959,11 +959,16 @@ static bool acpi_dev_needs_resume(struct device *dev, struct acpi_device *adev) int acpi_subsys_prepare(struct device *dev) { struct acpi_device *adev = ACPI_COMPANION(dev); - int ret; - ret = pm_generic_prepare(dev); - if (ret < 0) - return ret; + if (dev->driver && dev->driver->pm && dev->driver->pm->prepare) { + int ret = dev->driver->pm->prepare(dev); + + if (ret < 0) + return ret; + + if (!ret && dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_PREPARE)) + return 0; + } if (!adev || !pm_runtime_suspended(dev)) return 0; diff --git a/drivers/base/dd.c b/drivers/base/dd.c index ad44b40fe284..45575e134696 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -464,6 +464,7 @@ pinctrl_bind_failed: if (dev->pm_domain && dev->pm_domain->dismiss) dev->pm_domain->dismiss(dev); pm_runtime_reinit(dev); + dev_pm_set_driver_flags(dev, 0); switch (ret) { case -EPROBE_DEFER: @@ -869,6 +870,7 @@ static void __device_release_driver(struct device *dev, struct device *parent) if (dev->pm_domain && dev->pm_domain->dismiss) dev->pm_domain->dismiss(dev); pm_runtime_reinit(dev); + dev_pm_set_driver_flags(dev, 0); klist_remove(&dev->p->knode_driver); device_pm_check_callbacks(dev); diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index 9bbbbb13a9db..c0135cd95ada 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -1700,7 +1700,9 @@ unlock: * applies to suspend transitions, however. */ spin_lock_irq(&dev->power.lock); - dev->power.direct_complete = ret > 0 && state.event == PM_EVENT_SUSPEND; + dev->power.direct_complete = state.event == PM_EVENT_SUSPEND && + pm_runtime_suspended(dev) && ret > 0 && + !dev_pm_test_driver_flags(dev, DPM_FLAG_NEVER_SKIP); spin_unlock_irq(&dev->power.lock); return 0; } diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c index 11bd267fc137..68a32703b30a 100644 --- a/drivers/pci/pci-driver.c +++ b/drivers/pci/pci-driver.c @@ -689,8 +689,11 @@ static int pci_pm_prepare(struct device *dev) if (drv && drv->pm && drv->pm->prepare) { int error = drv->pm->prepare(dev); - if (error) + if (error < 0) return error; + + if (!error && dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_PREPARE)) + return 0; } return pci_dev_keep_suspended(to_pci_dev(dev)); } diff --git a/include/linux/device.h b/include/linux/device.h index c32e6f974d4a..fb9451599aca 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -1070,6 +1070,16 @@ static inline void dev_pm_syscore_device(struct device *dev, bool val) #endif } +static inline void dev_pm_set_driver_flags(struct device *dev, u32 flags) +{ + dev->power.driver_flags = flags; +} + +static inline bool dev_pm_test_driver_flags(struct device *dev, u32 flags) +{ + return !!(dev->power.driver_flags & flags); +} + static inline void device_lock(struct device *dev) { mutex_lock(&dev->mutex); diff --git a/include/linux/pm.h b/include/linux/pm.h index a0ceeccf2846..f10bad831bfa 100644 --- a/include/linux/pm.h +++ b/include/linux/pm.h @@ -550,6 +550,25 @@ struct pm_subsys_data { #endif }; +/* + * Driver flags to control system suspend/resume behavior. + * + * These flags can be set by device drivers at the probe time. They need not be + * cleared by the drivers as the driver core will take care of that. + * + * NEVER_SKIP: Do not skip system suspend/resume callbacks for the device. + * SMART_PREPARE: Check the return value of the driver's ->prepare callback. + * + * Setting SMART_PREPARE instructs bus types and PM domains which may want + * system suspend/resume callbacks to be skipped for the device to return 0 from + * their ->prepare callbacks if the driver's ->prepare callback returns 0 (in + * other words, the system suspend/resume callbacks can only be skipped for the + * device if its driver doesn't object against that). This flag has no effect + * if NEVER_SKIP is set. + */ +#define DPM_FLAG_NEVER_SKIP BIT(0) +#define DPM_FLAG_SMART_PREPARE BIT(1) + struct dev_pm_info { pm_message_t power_state; unsigned int can_wakeup:1; @@ -561,6 +580,7 @@ struct dev_pm_info { bool is_late_suspended:1; bool early_init:1; /* Owned by the PM core */ bool direct_complete:1; /* Owned by the PM core */ + u32 driver_flags; spinlock_t lock; #ifdef CONFIG_PM_SLEEP struct list_head entry; -- cgit v1.2.3 From c2eac4d3a115e2f511844e7bcf73f4e877fbf5da Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 25 Oct 2017 14:16:46 +0200 Subject: PCI / PM: Use the NEVER_SKIP driver flag Replace the PCI-specific flag PCI_DEV_FLAGS_NEEDS_RESUME with the PM core's DPM_FLAG_NEVER_SKIP one everywhere and drop it. Signed-off-by: Rafael J. Wysocki Acked-by: Greg Kroah-Hartman Acked-by: Bjorn Helgaas Reviewed-by: Ulf Hansson --- drivers/gpu/drm/i915/i915_drv.c | 2 +- drivers/misc/mei/pci-me.c | 2 +- drivers/misc/mei/pci-txe.c | 2 +- drivers/pci/pci.c | 3 +-- include/linux/pci.h | 7 +------ 5 files changed, 5 insertions(+), 11 deletions(-) (limited to 'include') diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c index 9f45cfeae775..f124de3a0668 100644 --- a/drivers/gpu/drm/i915/i915_drv.c +++ b/drivers/gpu/drm/i915/i915_drv.c @@ -1304,7 +1304,7 @@ int i915_driver_load(struct pci_dev *pdev, const struct pci_device_id *ent) * becaue the HDA driver may require us to enable the audio power * domain during system suspend. */ - pdev->dev_flags |= PCI_DEV_FLAGS_NEEDS_RESUME; + dev_pm_set_driver_flags(&pdev->dev, DPM_FLAG_NEVER_SKIP); ret = i915_driver_init_early(dev_priv, ent); if (ret < 0) diff --git a/drivers/misc/mei/pci-me.c b/drivers/misc/mei/pci-me.c index 4ff40d319676..f17e4b435fa9 100644 --- a/drivers/misc/mei/pci-me.c +++ b/drivers/misc/mei/pci-me.c @@ -223,7 +223,7 @@ static int mei_me_probe(struct pci_dev *pdev, const struct pci_device_id *ent) * MEI requires to resume from runtime suspend mode * in order to perform link reset flow upon system suspend. */ - pdev->dev_flags |= PCI_DEV_FLAGS_NEEDS_RESUME; + dev_pm_set_driver_flags(&pdev->dev, DPM_FLAG_NEVER_SKIP); /* * For not wake-able HW runtime pm framework diff --git a/drivers/misc/mei/pci-txe.c b/drivers/misc/mei/pci-txe.c index e38a5f144373..f911a08e3579 100644 --- a/drivers/misc/mei/pci-txe.c +++ b/drivers/misc/mei/pci-txe.c @@ -141,7 +141,7 @@ static int mei_txe_probe(struct pci_dev *pdev, const struct pci_device_id *ent) * MEI requires to resume from runtime suspend mode * in order to perform link reset flow upon system suspend. */ - pdev->dev_flags |= PCI_DEV_FLAGS_NEEDS_RESUME; + dev_pm_set_driver_flags(&pdev->dev, DPM_FLAG_NEVER_SKIP); /* * For not wake-able HW runtime pm framework diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 6078dfc11b11..374f5686e2bc 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -2166,8 +2166,7 @@ bool pci_dev_keep_suspended(struct pci_dev *pci_dev) if (!pm_runtime_suspended(dev) || pci_target_state(pci_dev, wakeup) != pci_dev->current_state - || platform_pci_need_resume(pci_dev) - || (pci_dev->dev_flags & PCI_DEV_FLAGS_NEEDS_RESUME)) + || platform_pci_need_resume(pci_dev)) return false; /* diff --git a/include/linux/pci.h b/include/linux/pci.h index f4f8ee5a7362..4b65fa4fb94e 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -205,13 +205,8 @@ enum pci_dev_flags { PCI_DEV_FLAGS_BRIDGE_XLATE_ROOT = (__force pci_dev_flags_t) (1 << 9), /* Do not use FLR even if device advertises PCI_AF_CAP */ PCI_DEV_FLAGS_NO_FLR_RESET = (__force pci_dev_flags_t) (1 << 10), - /* - * Resume before calling the driver's system suspend hooks, disabling - * the direct_complete optimization. - */ - PCI_DEV_FLAGS_NEEDS_RESUME = (__force pci_dev_flags_t) (1 << 11), /* Don't use Relaxed Ordering for TLPs directed at this device */ - PCI_DEV_FLAGS_NO_RELAXED_ORDERING = (__force pci_dev_flags_t) (1 << 12), + PCI_DEV_FLAGS_NO_RELAXED_ORDERING = (__force pci_dev_flags_t) (1 << 11), }; enum pci_irq_reroute_variant { -- cgit v1.2.3 From 0eab11c9ae3b3cc5dd76f20b81d0247647a6e96f Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 26 Oct 2017 12:12:08 +0200 Subject: PM / core: Add SMART_SUSPEND driver flag Define and document a SMART_SUSPEND flag to instruct bus types and PM domains that the system suspend callbacks provided by the driver can cope with runtime-suspended devices, so from the driver's perspective it should be safe to leave devices in runtime suspend during system suspend. Setting that flag may also cause middle-layer code (bus types, PM domains etc.) to skip invocations of the ->suspend_late and ->suspend_noirq callbacks provided by the driver if the device is in runtime suspend at the beginning of the "late" phase of the system-wide suspend transition, in which case the driver's system-wide resume callbacks may be invoked back-to-back with its ->runtime_suspend callback, so the driver has to be able to cope with that too. Signed-off-by: Rafael J. Wysocki Acked-by: Greg Kroah-Hartman Reviewed-by: Ulf Hansson --- Documentation/driver-api/pm/devices.rst | 20 ++++++++++++++++++++ drivers/base/power/main.c | 3 +++ include/linux/pm.h | 8 ++++++++ 3 files changed, 31 insertions(+) (limited to 'include') diff --git a/Documentation/driver-api/pm/devices.rst b/Documentation/driver-api/pm/devices.rst index 8add5b302a89..574dadd06dec 100644 --- a/Documentation/driver-api/pm/devices.rst +++ b/Documentation/driver-api/pm/devices.rst @@ -766,6 +766,26 @@ the state of devices (possibly except for resuming them from runtime suspend) from their ``->prepare`` and ``->suspend`` callbacks (or equivalent) *before* invoking device drivers' ``->suspend`` callbacks (or equivalent). +Some bus types and PM domains have a policy to resume all devices from runtime +suspend upfront in their ``->suspend`` callbacks, but that may not be really +necessary if the driver of the device can cope with runtime-suspended devices. +The driver can indicate that by setting ``DPM_FLAG_SMART_SUSPEND`` in +:c:member:`power.driver_flags` at the probe time, by passing it to the +:c:func:`dev_pm_set_driver_flags` helper. That also may cause middle-layer code +(bus types, PM domains etc.) to skip the ``->suspend_late`` and +``->suspend_noirq`` callbacks provided by the driver if the device remains in +runtime suspend at the beginning of the ``suspend_late`` phase of system-wide +suspend (or in the ``poweroff_late`` phase of hibernation), when runtime PM +has been disabled for it, under the assumption that its state should not change +after that point until the system-wide transition is over. If that happens, the +driver's system-wide resume callbacks, if present, may still be invoked during +the subsequent system-wide resume transition and the device's runtime power +management status may be set to "active" before enabling runtime PM for it, +so the driver must be prepared to cope with the invocation of its system-wide +resume callbacks back-to-back with its ``->runtime_suspend`` one (without the +intervening ``->runtime_resume`` and so on) and the final state of the device +must reflect the "active" status for runtime PM in that case. + During system-wide resume from a sleep state it's easiest to put devices into the full-power state, as explained in :file:`Documentation/power/runtime_pm.txt`. Refer to that document for more information regarding this particular issue as diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index c0135cd95ada..8d9024017645 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -1652,6 +1652,9 @@ static int device_prepare(struct device *dev, pm_message_t state) if (dev->power.syscore) return 0; + WARN_ON(dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) && + !pm_runtime_enabled(dev)); + /* * If a device's parent goes into runtime suspend at the wrong time, * it won't be possible to resume the device. To prevent this we diff --git a/include/linux/pm.h b/include/linux/pm.h index f10bad831bfa..43b5418e05bb 100644 --- a/include/linux/pm.h +++ b/include/linux/pm.h @@ -558,6 +558,7 @@ struct pm_subsys_data { * * NEVER_SKIP: Do not skip system suspend/resume callbacks for the device. * SMART_PREPARE: Check the return value of the driver's ->prepare callback. + * SMART_SUSPEND: No need to resume the device from runtime suspend. * * Setting SMART_PREPARE instructs bus types and PM domains which may want * system suspend/resume callbacks to be skipped for the device to return 0 from @@ -565,9 +566,16 @@ struct pm_subsys_data { * other words, the system suspend/resume callbacks can only be skipped for the * device if its driver doesn't object against that). This flag has no effect * if NEVER_SKIP is set. + * + * Setting SMART_SUSPEND instructs bus types and PM domains which may want to + * runtime resume the device upfront during system suspend that doing so is not + * necessary from the driver's perspective. It also may cause them to skip + * invocations of the ->suspend_late and ->suspend_noirq callbacks provided by + * the driver if they decide to leave the device in runtime suspend. */ #define DPM_FLAG_NEVER_SKIP BIT(0) #define DPM_FLAG_SMART_PREPARE BIT(1) +#define DPM_FLAG_SMART_SUSPEND BIT(2) struct dev_pm_info { pm_message_t power_state; -- cgit v1.2.3 From c4b65157aeefad29b2351a00a010e8c40ce7fd0e Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 26 Oct 2017 12:12:22 +0200 Subject: PCI / PM: Take SMART_SUSPEND driver flag into account Make the PCI bus type take DPM_FLAG_SMART_SUSPEND into account in its system-wide PM callbacks and make sure that all code that should not run in parallel with pci_pm_runtime_resume() is executed in the "late" phases of system suspend, freeze and poweroff transitions. [Note that the pm_runtime_suspended() check in pci_dev_keep_suspended() is an optimization, because if is not passed, all of the subsequent checks may be skipped and some of them are much more overhead in general.] Also use the observation that if the device is in runtime suspend at the beginning of the "late" phase of a system-wide suspend-like transition, its state cannot change going forward (runtime PM is disabled for it at that time) until the transition is over and the subsequent system-wide PM callbacks should be skipped for it (as they generally assume the device to not be suspended), so add checks for that in pci_pm_suspend_late/noirq(), pci_pm_freeze_late/noirq() and pci_pm_poweroff_late/noirq(). Moreover, if pci_pm_resume_noirq() or pci_pm_restore_noirq() is called during the subsequent system-wide resume transition and if the device was left in runtime suspend previously, its runtime PM status needs to be changed to "active" as it is going to be put into the full-power state, so add checks for that too to these functions. In turn, if pci_pm_thaw_noirq() runs after the device has been left in runtime suspend, the subsequent "thaw" callbacks need to be skipped for it (as they may not work correctly with a suspended device), so set the power.direct_complete flag for the device then to make the PM core skip those callbacks. In addition to the above add a core helper for checking if DPM_FLAG_SMART_SUSPEND is set and the device runtime PM status is "suspended" at the same time, which is done quite often in the new code (and will be done elsewhere going forward too). Signed-off-by: Rafael J. Wysocki Acked-by: Greg Kroah-Hartman Acked-by: Bjorn Helgaas --- Documentation/power/pci.txt | 14 ++++++ drivers/base/power/main.c | 6 +++ drivers/pci/pci-driver.c | 103 ++++++++++++++++++++++++++++++++++++-------- include/linux/pm.h | 2 + 4 files changed, 108 insertions(+), 17 deletions(-) (limited to 'include') 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) -- cgit v1.2.3 From 05087360fd7acf2cc9b7bbb243c12765c44c7693 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Fri, 27 Oct 2017 10:10:16 +0200 Subject: ACPI / PM: Take SMART_SUSPEND driver flag into account Make the ACPI PM domain take DPM_FLAG_SMART_SUSPEND into account in its system suspend callbacks. [Note that the pm_runtime_suspended() check in acpi_dev_needs_resume() is an optimization, because if is not passed, all of the subsequent checks may be skipped and some of them are much more overhead in general.] Also use the observation that if the device is in runtime suspend at the beginning of the "late" phase of a system-wide suspend-like transition, its state cannot change going forward (runtime PM is disabled for it at that time) until the transition is over and the subsequent system-wide PM callbacks should be skipped for it (as they generally assume the device to not be suspended), so add checks for that in acpi_subsys_suspend_late/noirq() and acpi_subsys_freeze_late/noirq(). Moreover, if acpi_subsys_resume_noirq() is called during the subsequent system-wide resume transition and if the device was left in runtime suspend previously, its runtime PM status needs to be changed to "active" as it is going to be put into the full-power state going forward, so add a check for that too in there. In turn, if acpi_subsys_thaw_noirq() runs after the device has been left in runtime suspend, the subsequent "thaw" callbacks need to be skipped for it (as they may not work correctly with a suspended device), so set the power.direct_complete flag for the device then to make the PM core skip those callbacks. On top of the above, make the analogous changes in the acpi_lpss driver that uses the ACPI PM domain callbacks. Signed-off-by: Rafael J. Wysocki Acked-by: Greg Kroah-Hartman --- drivers/acpi/acpi_lpss.c | 13 +++++- drivers/acpi/device_pm.c | 113 +++++++++++++++++++++++++++++++++++++++++++---- include/linux/acpi.h | 10 +++++ 3 files changed, 126 insertions(+), 10 deletions(-) (limited to 'include') diff --git a/drivers/acpi/acpi_lpss.c b/drivers/acpi/acpi_lpss.c index 04d32bdb5a95..de7385b824e1 100644 --- a/drivers/acpi/acpi_lpss.c +++ b/drivers/acpi/acpi_lpss.c @@ -849,8 +849,12 @@ static int acpi_lpss_resume(struct device *dev) #ifdef CONFIG_PM_SLEEP static int acpi_lpss_suspend_late(struct device *dev) { - int ret = pm_generic_suspend_late(dev); + int ret; + + if (dev_pm_smart_suspend_and_suspended(dev)) + return 0; + ret = pm_generic_suspend_late(dev); return ret ? ret : acpi_lpss_suspend(dev, device_may_wakeup(dev)); } @@ -889,10 +893,17 @@ static struct dev_pm_domain acpi_lpss_pm_domain = { .complete = acpi_subsys_complete, .suspend = acpi_subsys_suspend, .suspend_late = acpi_lpss_suspend_late, + .suspend_noirq = acpi_subsys_suspend_noirq, + .resume_noirq = acpi_subsys_resume_noirq, .resume_early = acpi_lpss_resume_early, .freeze = acpi_subsys_freeze, + .freeze_late = acpi_subsys_freeze_late, + .freeze_noirq = acpi_subsys_freeze_noirq, + .thaw_noirq = acpi_subsys_thaw_noirq, .poweroff = acpi_subsys_suspend, .poweroff_late = acpi_lpss_suspend_late, + .poweroff_noirq = acpi_subsys_suspend_noirq, + .restore_noirq = acpi_subsys_resume_noirq, .restore_early = acpi_lpss_resume_early, #endif .runtime_suspend = acpi_lpss_runtime_suspend, diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c index b4dcc6144e6b..3d6ec51d2bbc 100644 --- a/drivers/acpi/device_pm.c +++ b/drivers/acpi/device_pm.c @@ -936,7 +936,8 @@ static bool acpi_dev_needs_resume(struct device *dev, struct acpi_device *adev) u32 sys_target = acpi_target_system_state(); int ret, state; - if (device_may_wakeup(dev) != !!adev->wakeup.prepare_count) + if (!pm_runtime_suspended(dev) || !adev || + device_may_wakeup(dev) != !!adev->wakeup.prepare_count) return true; if (sys_target == ACPI_STATE_S0) @@ -970,9 +971,6 @@ int acpi_subsys_prepare(struct device *dev) return 0; } - if (!adev || !pm_runtime_suspended(dev)) - return 0; - return !acpi_dev_needs_resume(dev, adev); } EXPORT_SYMBOL_GPL(acpi_subsys_prepare); @@ -998,12 +996,17 @@ EXPORT_SYMBOL_GPL(acpi_subsys_complete); * acpi_subsys_suspend - Run the device driver's suspend callback. * @dev: Device to handle. * - * Follow PCI and resume devices suspended at run time before running their - * system suspend callbacks. + * Follow PCI and resume devices from runtime suspend before running their + * system suspend callbacks, unless the driver can cope with runtime-suspended + * devices during system suspend and there are no ACPI-specific reasons for + * resuming them. */ int acpi_subsys_suspend(struct device *dev) { - pm_runtime_resume(dev); + if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) || + acpi_dev_needs_resume(dev, ACPI_COMPANION(dev))) + pm_runtime_resume(dev); + return pm_generic_suspend(dev); } EXPORT_SYMBOL_GPL(acpi_subsys_suspend); @@ -1017,11 +1020,47 @@ EXPORT_SYMBOL_GPL(acpi_subsys_suspend); */ int acpi_subsys_suspend_late(struct device *dev) { - int ret = pm_generic_suspend_late(dev); + int ret; + + if (dev_pm_smart_suspend_and_suspended(dev)) + return 0; + + ret = pm_generic_suspend_late(dev); return ret ? ret : acpi_dev_suspend(dev, device_may_wakeup(dev)); } EXPORT_SYMBOL_GPL(acpi_subsys_suspend_late); +/** + * acpi_subsys_suspend_noirq - Run the device driver's "noirq" suspend callback. + * @dev: Device to suspend. + */ +int acpi_subsys_suspend_noirq(struct device *dev) +{ + if (dev_pm_smart_suspend_and_suspended(dev)) + return 0; + + return pm_generic_suspend_noirq(dev); +} +EXPORT_SYMBOL_GPL(acpi_subsys_suspend_noirq); + +/** + * acpi_subsys_resume_noirq - Run the device driver's "noirq" resume callback. + * @dev: Device to handle. + */ +int acpi_subsys_resume_noirq(struct device *dev) +{ + /* + * 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 will be put into D0 going forward. + */ + if (dev_pm_smart_suspend_and_suspended(dev)) + pm_runtime_set_active(dev); + + return pm_generic_resume_noirq(dev); +} +EXPORT_SYMBOL_GPL(acpi_subsys_resume_noirq); + /** * acpi_subsys_resume_early - Resume device using ACPI. * @dev: Device to Resume. @@ -1049,11 +1088,60 @@ int acpi_subsys_freeze(struct device *dev) * runtime-suspended devices should not be touched during freeze/thaw * transitions. */ - pm_runtime_resume(dev); + if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND)) + pm_runtime_resume(dev); + return pm_generic_freeze(dev); } EXPORT_SYMBOL_GPL(acpi_subsys_freeze); +/** + * acpi_subsys_freeze_late - Run the device driver's "late" freeze callback. + * @dev: Device to handle. + */ +int acpi_subsys_freeze_late(struct device *dev) +{ + + if (dev_pm_smart_suspend_and_suspended(dev)) + return 0; + + return pm_generic_freeze_late(dev); +} +EXPORT_SYMBOL_GPL(acpi_subsys_freeze_late); + +/** + * acpi_subsys_freeze_noirq - Run the device driver's "noirq" freeze callback. + * @dev: Device to handle. + */ +int acpi_subsys_freeze_noirq(struct device *dev) +{ + + if (dev_pm_smart_suspend_and_suspended(dev)) + return 0; + + return pm_generic_freeze_noirq(dev); +} +EXPORT_SYMBOL_GPL(acpi_subsys_freeze_noirq); + +/** + * acpi_subsys_thaw_noirq - Run the device driver's "noirq" thaw callback. + * @dev: Device to handle. + */ +int acpi_subsys_thaw_noirq(struct device *dev) +{ + /* + * If the device is in runtime suspend, the "thaw" code may not work + * correctly with it, so skip the driver callback 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; + } + + return pm_generic_thaw_noirq(dev); +} +EXPORT_SYMBOL_GPL(acpi_subsys_thaw_noirq); #endif /* CONFIG_PM_SLEEP */ static struct dev_pm_domain acpi_general_pm_domain = { @@ -1065,10 +1153,17 @@ static struct dev_pm_domain acpi_general_pm_domain = { .complete = acpi_subsys_complete, .suspend = acpi_subsys_suspend, .suspend_late = acpi_subsys_suspend_late, + .suspend_noirq = acpi_subsys_suspend_noirq, + .resume_noirq = acpi_subsys_resume_noirq, .resume_early = acpi_subsys_resume_early, .freeze = acpi_subsys_freeze, + .freeze_late = acpi_subsys_freeze_late, + .freeze_noirq = acpi_subsys_freeze_noirq, + .thaw_noirq = acpi_subsys_thaw_noirq, .poweroff = acpi_subsys_suspend, .poweroff_late = acpi_subsys_suspend_late, + .poweroff_noirq = acpi_subsys_suspend_noirq, + .restore_noirq = acpi_subsys_resume_noirq, .restore_early = acpi_subsys_resume_early, #endif }, diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 0ada2a948b44..dc1ebfeeb5ec 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -885,17 +885,27 @@ int acpi_dev_suspend_late(struct device *dev); int acpi_subsys_prepare(struct device *dev); void acpi_subsys_complete(struct device *dev); int acpi_subsys_suspend_late(struct device *dev); +int acpi_subsys_suspend_noirq(struct device *dev); +int acpi_subsys_resume_noirq(struct device *dev); int acpi_subsys_resume_early(struct device *dev); int acpi_subsys_suspend(struct device *dev); int acpi_subsys_freeze(struct device *dev); +int acpi_subsys_freeze_late(struct device *dev); +int acpi_subsys_freeze_noirq(struct device *dev); +int acpi_subsys_thaw_noirq(struct device *dev); #else static inline int acpi_dev_resume_early(struct device *dev) { return 0; } static inline int acpi_subsys_prepare(struct device *dev) { return 0; } static inline void acpi_subsys_complete(struct device *dev) {} static inline int acpi_subsys_suspend_late(struct device *dev) { return 0; } +static inline int acpi_subsys_suspend_noirq(struct device *dev) { return 0; } +static inline int acpi_subsys_resume_noirq(struct device *dev) { return 0; } static inline int acpi_subsys_resume_early(struct device *dev) { return 0; } static inline int acpi_subsys_suspend(struct device *dev) { return 0; } static inline int acpi_subsys_freeze(struct device *dev) { return 0; } +static inline int acpi_subsys_freeze_late(struct device *dev) { return 0; } +static inline int acpi_subsys_freeze_noirq(struct device *dev) { return 0; } +static inline int acpi_subsys_thaw_noirq(struct device *dev) { return 0; } #endif #ifdef CONFIG_ACPI -- cgit v1.2.3