user/sven/linux.git/include/linux/pm.h, branch v4.11.4

PM / core / docs: Convert sleep states API document to reST

2017-02-06T18:25:55Z

Move the document describing the system sleep state transitions API for devices to Documentation/driver-api/pm/, convert it to reST and update it to use current terminology. Also remove the remaining reference to the old version of it from pm.h. The new document still contains references to some documents in the .txt format that will be converted later. Signed-off-by: Rafael J. Wysocki Signed-off-by: Jonathan Corbet

PM / core: Update kerneldoc comments in pm.h

2017-02-06T18:11:19Z

Refresh the struct dev_pm_ops kerneldoc comment, so that it looks better and is more readable after processing by Sphinx, and drop the kerneldoc marker from a few other comments ("PM_EVENT_ messages" and a couple of enum types declarations) which are not proper kerneldoc and generally confuse Sphinx. Also change the comment describing struct dev_pm_domain into a kerneldoc one. Signed-off-by: Rafael J. Wysocki Signed-off-by: Jonathan Corbet

Merge tag 'driver-core-4.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2016-12-13T19:42:18Z

Pull driver core updates from Greg KH: "Here's the new driver core patches for 4.10-rc1. Big thing here is the nice addition of "functional dependencies" to the driver core. The idea has been talked about for a very long time, great job to Rafael for stepping up and implementing it. It's been tested for longer than the 4.9-rc1 date, we held off on merging it earlier in order to feel more comfortable about it. Other than that, it's just a handful of small other patches, some good cleanups to the mess that is the firmware class code, and we have a test driver for the deferred probe logic. All of these have been in linux-next for a while with no reported issues" * tag 'driver-core-4.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (30 commits) firmware: Correct handling of fw_state_wait() return value driver core: Silence device links sphinx warning firmware: remove warning at documentation generation time drivers: base: dma-mapping: Fix typo in dmam_alloc_non_coherent comments driver core: test_async: fix up typo found by 0-day firmware: move fw_state_is_done() into UHM section firmware: do not use fw_lock for fw_state protection firmware: drop bit ops in favor of simple state machine firmware: refactor loading status firmware: fix usermode helper fallback loading driver core: firmware_class: convert to use class_groups driver core: devcoredump: convert to use class_groups driver core: class: add class_groups support kernfs: Declare two local data structures static driver-core: fix platform_no_drv_owner.cocci warnings drivers/base/memory.c: Remove unused 'first_page' variable driver core: add CLASS_ATTR_WO() drivers: base: cacheinfo: support DT overrides for cache properties drivers: base: cacheinfo: add pr_fmt logging drivers: base: cacheinfo: fix boot error message when acpi is enabled ...

PM / runtime: Optimize the use of device links

2016-10-31T17:42:51Z

If the device has no links to suppliers that should be used for runtime PM (links with DEVICE_LINK_PM_RUNTIME set), there is no reason to walk the list of suppliers for that device during runtime suspend and resume. Add a simple mechanism to detect that case and possibly avoid the extra unnecessary overhead. Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

driver core: Functional dependencies tracking support

2016-10-31T17:36:20Z

Currently, there is a problem with taking functional dependencies between devices into account. What I mean by a "functional dependency" is when the driver of device B needs device A to be functional and (generally) its driver to be present in order to work properly. This has certain consequences for power management (suspend/resume and runtime PM ordering) and shutdown ordering of these devices. In general, it also implies that the driver of A needs to be working for B to be probed successfully and it cannot be unbound from the device before the B's driver. Support for representing those functional dependencies between devices is added here to allow the driver core to track them and act on them in certain cases where applicable. The argument for doing that in the driver core is that there are quite a few distinct use cases involving device dependencies, they are relatively hard to get right in a driver (if one wants to address all of them properly) and it only gets worse if multiplied by the number of drivers potentially needing to do it. Morever, at least one case (asynchronous system suspend/resume) cannot be handled in a single driver at all, because it requires the driver of A to wait for B to suspend (during system suspend) and the driver of B to wait for A to resume (during system resume). For this reason, represent dependencies between devices as "links", with the help of struct device_link objects each containing pointers to the "linked" devices, a list node for each of them, status information, flags, and an RCU head for synchronization. Also add two new list heads, representing the lists of links to the devices that depend on the given one (consumers) and to the devices depended on by it (suppliers), and a "driver presence status" field (needed for figuring out initial states of device links) to struct device. The entire data structure consisting of all of the lists of link objects for all devices is protected by a mutex (for link object addition/removal and for list walks during device driver probing and removal) and by SRCU (for list walking in other case that will be introduced by subsequent change sets). If CONFIG_SRCU is not selected, however, an rwsem is used for protecting the entire data structure. In addition, each link object has an internal status field whose value reflects whether or not drivers are bound to the devices pointed to by the link or probing/removal of their drivers is in progress etc. That field is only modified under the device links mutex, but it may be read outside of it in some cases (introduced by subsequent change sets), so modifications of it are annotated with WRITE_ONCE(). New links are added by calling device_link_add() which takes three arguments: pointers to the devices in question and flags. In particular, if DL_FLAG_STATELESS is set in the flags, the link status is not to be taken into account for this link and the driver core will not manage it. In turn, if DL_FLAG_AUTOREMOVE is set in the flags, the driver core will remove the link automatically when the consumer device driver unbinds from it. One of the actions carried out by device_link_add() is to reorder the lists used for device shutdown and system suspend/resume to put the consumer device along with all of its children and all of its consumers (and so on, recursively) to the ends of those lists in order to ensure the right ordering between all of the supplier and consumer devices. For this reason, it is not possible to create a link between two devices if the would-be supplier device already depends on the would-be consumer device as either a direct descendant of it or a consumer of one of its direct descendants or one of its consumers and so on. There are two types of link objects, persistent and non-persistent. The persistent ones stay around until one of the target devices is deleted, while the non-persistent ones are removed automatically when the consumer driver unbinds from its device (ie. they are assumed to be valid only as long as the consumer device has a driver bound to it). Persistent links are created by default and non-persistent links are created when the DL_FLAG_AUTOREMOVE flag is passed to device_link_add(). Both persistent and non-persistent device links can be deleted with an explicit call to device_link_del(). Links created without the DL_FLAG_STATELESS flag set are managed by the driver core using a simple state machine. There are 5 states each link can be in: DORMANT (unused), AVAILABLE (the supplier driver is present and functional), CONSUMER_PROBE (the consumer driver is probing), ACTIVE (both supplier and consumer drivers are present and functional), and SUPPLIER_UNBIND (the supplier driver is unbinding). The driver core updates the link state automatically depending on what happens to the linked devices and for each link state specific actions are taken in addition to that. For example, if the supplier driver unbinds from its device, the driver core will also unbind the drivers of all of its consumers automatically under the assumption that they cannot function properly without the supplier. Analogously, the driver core will only allow the consumer driver to bind to its device if the supplier driver is present and functional (ie. the link is in the AVAILABLE state). If that's not the case, it will rely on the existing deferred probing mechanism to wait for the supplier driver to become available. Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

docs: fix locations of several documents that got moved

2016-10-24T10:12:35Z

The previous patch renamed several files that are cross-referenced along the Kernel documentation. Adjust the links to point to the right places. Signed-off-by: Mauro Carvalho Chehab

PM / Runtime: Move ignore_children flag under CONFIG_PM

2016-04-21T23:32:37Z

The ignore_children flag is used only when CONFIG_PM is set, so let's move it into that section within the struct dev_pm_info. Move also the corresponding pm_suspend_ignore_children() API out of device.h into pm_runtime.h, to be consistent with similar APIs. Unfortunate this causes the Toshiba PCI SD mmc host driver to fail to compile as it needs pm_runtime.h, so let's fix this here as well. Signed-off-by: Ulf Hansson Acked-by: Pavel Machek Signed-off-by: Rafael J. Wysocki

PM / sleep: Go direct_complete if driver has no callbacks

2016-01-08T00:12:06Z

If a suitable prepare callback cannot be found for a given device and its driver has no PM callbacks at all, assume that it can go direct to complete when the system goes to sleep. The reason for this is that there's lots of devices in a system that do no PM at all and there's no reason for them to prevent their ancestors to do direct_complete if they can support it. Signed-off-by: Tomeu Vizoso Reviewed-by: Ulf Hansson Signed-off-by: Rafael J. Wysocki

PM / PCI / ACPI: Kick devices that might have been reset by firmware

2015-10-14T00:17:34Z

There is a concern that if the platform firmware was involved in the system resume that's being completed, some devices might have been reset by it and if those devices had the power.direct_complete flag set during the preceding suspend transition, they may stay in a reset-power-on state indefinitely (until they are runtime-resumed and then suspended again). That may not be a big deal from the individual device's perspective, but if the system is an SoC, it may be prevented from entering deep SoC-wide low-power states on idle because of that. The devices that are most likely to be affected by this issue are PCI devices and ACPI-enumerated devices using the general ACPI PM domain, so to prevent it from happening for those devices, force a runtime resume for them if they have their power.direct_complete flags set and the platform firmware was involved in the resume transition currently in progress. Signed-off-by: Rafael J. Wysocki

Merge branch 'pm-wakeirq'

2015-06-18T23:18:14Z

* pm-wakeirq: PM / wakeirq: Fix typo in prototype for dev_pm_set_dedicated_wake_irq PM / Wakeirq: Add automated device wake IRQ handling