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2011-05-18PM: Introduce generic prepare and complete callbacks for subsystemsRafael J. Wysocki1-0/+39
Introduce generic .prepare() and .complete() power management callbacks, currently missing, that can be used by subsystems and power domains and export them. Provide NULL definitions of all the generic system sleep callbacks for CONFIG_PM_SLEEP unset. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-05-18PM: Allow drivers to allocate memory from .prepare() callbacks safelyRafael J. Wysocki1-6/+12
If device drivers allocate substantial amounts of memory (above 1 MB) in their hibernate .freeze() callbacks (or in their legacy suspend callbcks during hibernation), the subsequent creation of hibernate image may fail due to the lack of memory. This is the case, because the drivers' .freeze() callbacks are executed after the hibernate memory preallocation has been carried out and the preallocated amount of memory may be too small to cover the new driver allocations. Unfortunately, the drivers' .prepare() callbacks also are executed after the hibernate memory preallocation has completed, so they are not suitable for allocating additional memory either. Thus the only way a driver can safely allocate memory during hibernation is to use a hibernate/suspend notifier. However, the notifiers are called before the freezing of user space and the drivers wanting to use them for allocating additional memory may not know how much memory needs to be allocated at that point. To let device drivers overcome this difficulty rework the hibernation sequence so that the memory preallocation is carried out after the drivers' .prepare() callbacks have been executed, so that the .prepare() callbacks can be used for allocating additional memory to be used by the drivers' .freeze() callbacks. Update documentation to match the new behavior of the code. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-05-18PM: Remove CONFIG_PM_VERBOSERafael J. Wysocki1-2/+1
Now that we have CONFIG_DYNAMIC_DEBUG there is no need for yet another flag causing dev_dbg() and pr_debug() statements in the core PM code to produce output. Moreover, CONFIG_PM_VERBOSE causes so much output to be generated that it's not really useful and almost no one sets it. References: https://bugzilla.kernel.org/show_bug.cgi?id=23182 Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-05-18Merge branch 'power-domains' into for-linusRafael J. Wysocki5-169/+494
* power-domains: PM: Fix build issue in clock_ops.c for CONFIG_PM_RUNTIME unset PM: Revert "driver core: platform_bus: allow runtime override of dev_pm_ops" OMAP1 / PM: Use generic clock manipulation routines for runtime PM PM / Runtime: Generic clock manipulation rountines for runtime PM (v6) PM / Runtime: Add subsystem data field to struct dev_pm_info OMAP2+ / PM: move runtime PM implementation to use device power domains PM / Platform: Use generic runtime PM callbacks directly shmobile: Use power domains for platform runtime PM PM: Export platform bus type's default PM callbacks PM: Make power domain callbacks take precedence over subsystem ones
2011-05-18Merge branch 'syscore' into for-linusRafael J. Wysocki3-209/+2
* syscore: PM: Remove sysdev suspend, resume and shutdown operations PM / PowerPC: Use struct syscore_ops instead of sysdevs for PM PM / UNICORE32: Use struct syscore_ops instead of sysdevs for PM PM / AVR32: Use struct syscore_ops instead of sysdevs for PM PM / Blackfin: Use struct syscore_ops instead of sysdevs for PM ARM / Samsung: Use struct syscore_ops for "core" power management ARM / PXA: Use struct syscore_ops for "core" power management ARM / SA1100: Use struct syscore_ops for "core" power management ARM / Integrator: Use struct syscore_ops for core PM ARM / OMAP: Use struct syscore_ops for "core" power management ARM: Use struct syscore_ops instead of sysdevs for PM in common code
2011-05-18PM / Wakeup: Remove useless synchronize_rcu() callEric Dumazet1-1/+0
wakeup_source_add() adds an item into wakeup_sources list. There is no need to call synchronize_rcu() at this point. Its only needed in wakeup_source_remove() Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-05-18PM / Wakeup: Fix build warning related to the "wakeup" sysfs fileRafael J. Wysocki1-2/+2
The "wakeup" device sysfs file is only created if CONFIG_PM_SLEEP is set, so put it under CONFIG_PM_SLEEP and make a build warning related to it go away. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-05-18PM: Print a warning if firmware is requested when tasks are frozenRafael J. Wysocki1-0/+5
Some drivers erroneously use request_firmware() from their ->resume() (or ->thaw(), or ->restore()) callbacks, which is not going to work unless the firmware has been built in. This causes system resume to stall until the firmware-loading timeout expires, which makes users think that the resume has failed and reboot their machines unnecessarily. For this reason, make _request_firmware() print a warning and return immediately with error code if it has been called when tasks are frozen and it's impossible to start any new usermode helpers. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Reviewed-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
2011-05-18PM / Runtime: Rework runtime PM handling during driver removalRafael J. Wysocki1-3/+3
The driver core tries to prevent race conditions between runtime PM and driver removal from happening by incrementing the runtime PM usage counter of the device and executing pm_runtime_barrier() before running the bus notifier and the ->remove() callbacks provided by the device's subsystem or driver. This guarantees that, if a future runtime suspend of the device has been scheduled or a runtime resume or idle request has been queued up right before the driver removal, it will be canceled or waited for to complete and no other asynchronous runtime suspend or idle requests for the device will be put into the PM workqueue until the ->remove() callback returns. However, it doesn't prevent resume requests from being queued up after pm_runtime_barrier() has been called and it doesn't prevent pm_runtime_resume() from executing the device subsystem's runtime resume callback. Morever, it prevents the device's subsystem or driver from putting the device into the suspended state by calling pm_runtime_suspend() from its ->remove() routine. This turns out to be a major inconvenience for some subsystems and drivers that want to leave the devices they handle in the suspended state. To really prevent runtime PM callbacks from racing with the bus notifier callback in __device_release_driver(), which is necessary, because the notifier is used by some subsystems to carry out operations affecting the runtime PM functionality, use pm_runtime_get_sync() instead of the combination of pm_runtime_get_noresume() and pm_runtime_barrier(). This will resume the device if it's in the suspended state and will prevent it from being suspended again until pm_runtime_put_*() is called. To allow subsystems and drivers to put devices into the suspended state by calling pm_runtime_suspend() from their ->remove() routines, execute pm_runtime_put_sync() after running the bus notifier in __device_release_driver(). This will require subsystems and drivers to make their ->remove() callbacks avoid races with runtime PM directly, but it will allow of more flexibility in the handling of devices during the removal of their drivers. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-05-16PM: Fix build issue in clock_ops.c for CONFIG_PM_RUNTIME unsetRafael J. Wysocki1-0/+1
Fix a build issue in drivers/base/power/clock_ops.c occuring when CONFIG_PM_RUNTIME is not set. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-05-16PM: Revert "driver core: platform_bus: allow runtime override of dev_pm_ops"Kevin Hilman1-35/+0
The platform_bus_set_pm_ops() operation is deprecated in favor of the new device power domain infrastructre implemented in commit 7538e3db6e015e890825fbd9f8659952896ddd5b (PM: add support for device power domains) Signed-off-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-05-13drivers/base/memory.c: fix warning due to "memory hotplug: Speed up ↵Andrew Morton1-1/+1
add/remove when blocks are larger than PAGES_PER_SECTION" drivers/base/memory.c: In function 'memory_block_change_state': drivers/base/memory.c:281: warning: unused variable 'i' less beer, more testing Cc: Anton Blanchard <anton@samba.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-05-12memory hotplug: Speed up add/remove when blocks are larger than ↵Anton Blanchard1-16/+8
PAGES_PER_SECTION On ppc64 the minimum memory section for hotplug is 16MB but most recent machines have a memory block size of 256MB. This means memory_block_change_state does 16 separate calls to memory_section_action. This also means we call the notifiers 16 times and the hook in the ehea network driver is quite costly. To offline one 256MB region takes: # time echo offline > /sys/devices/system/memory/memory32/state 7.9s This patch removes the loop and calls online_pages or remove_memory once for the entire region and in doing so makes the logic simpler since we don't have to back out if things fail part way through. The same test to offline one region now takes: # time echo online > /sys/devices/system/memory/memory32/state 0.67s Over 11 times faster. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-05-11PM: Remove sysdev suspend, resume and shutdown operationsRafael J. Wysocki3-209/+2
Since suspend, resume and shutdown operations in struct sysdev_class and struct sysdev_driver are not used any more, remove them. Also drop sysdev_suspend(), sysdev_resume() and sysdev_shutdown() used for executing those operations and modify all of their users accordingly. This reduces kernel code size quite a bit and reduces its complexity. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-04-30PM / Runtime: Generic clock manipulation rountines for runtime PM (v6)Rafael J. Wysocki2-0/+431
Many different platforms and subsystems may want to disable device clocks during suspend and enable them during resume which is going to be done in a very similar way in all those cases. For this reason, provide generic routines for the manipulation of device clocks during suspend and resume. Convert the ARM shmobile platform to using the new routines. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-04-29PM / Platform: Use generic runtime PM callbacks directlyRafael J. Wysocki1-28/+3
Once shmobile platforms have been converted to using power domains for overriding the platform bus type's PM callbacks, it isn't necessary to use the __weakly defined wrappers around the generinc runtime PM callbacks in the platform bus type any more. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-04-29PM: Export platform bus type's default PM callbacksRafael J. Wysocki1-54/+18
Export the default PM callbacks defined for the platform bus type so that they can be used by power domains for suspending and resuming platform devices in the future. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-04-29PM: Make power domain callbacks take precedence over subsystem onesRafael J. Wysocki2-52/+41
Change the PM core's behavior related to power domains in such a way that, if a power domain is defined for a given device, its callbacks will be executed instead of and not in addition to the device subsystem's PM callbacks. The idea behind the initial implementation of power domains handling by the PM core was that power domain callbacks would be executed in addition to subsystem callbacks, so that it would be possible to extend the subsystem callbacks by using power domains. It turns out, however, that this wouldn't be really convenient in some important situations. For example, there are systems in which power can only be removed from entire power domains. On those systems it is not desirable to execute device drivers' PM callbacks until it is known that power is going to be removed from the devices in question, which means that they should be executed by power domain callbacks rather then by subsystem (e.g. bus type) PM callbacks, because subsystems generally have no information about what devices belong to which power domain. Thus, for instance, if the bus type in question is the platform bus type, its PM callbacks generally should not be called in addition to power domain callbacks, because they run device drivers' callbacks unconditionally if defined. While in principle the default subsystem PM callbacks, or a subset of them, may be replaced with different functions, it doesn't seem correct to do so, because that would change the subsystem's behavior with respect to all devices in the system, regardless of whether or not they belong to any power domains. Thus, the only remaining option is to make power domain callbacks take precedence over subsystem callbacks. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Kevin Hilman <khilman@ti.com>
2011-04-26PM / Wakeup: Fix initialization of wakeup-related device sysfs filesRafael J. Wysocki2-1/+2
It turns out that some PCI devices are only found to be wakeup-capable during registration, in which case, when device_set_wakeup_capable() is called, device_is_registered() already returns 'true' for the given device, but dpm_sysfs_add() hasn't been called for it yet. This leads to situations in which the device's power.can_wakeup flag is not set as requested because of failing wakeup_sysfs_add() and its wakeup-related sysfs files are not created, although they should be present. This is a post-2.6.38 regression introduced by commit cb8f51bdadb7969139c2e39c2defd4cde98c1 (PM: Do not create wakeup sysfs files for devices that cannot wake up). To work around this problem initialize the device's power.entry field to an empty list head and make device_set_wakeup_capable() check if it is still empty before attempting to add the devices wakeup-related sysfs files with wakeup_sysfs_add(). Namely, if power.entry is still empty at this point, device_pm_add() hasn't been called yet for the device and its wakeup-related files will be created later, so device_set_wakeup_capable() doesn't have to create them. Reported-and-tested-by: Tino Keitel <tino.keitel@tikei.de> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-04-26Merge branch 'master' into for-nextJiri Kosina6-16/+27
Fast-forwarded to current state of Linus' tree as there are patches to be applied for files that didn't exist on the old branch.
2011-04-26drivers:base:fix the coding format of memory.cWanlong Gao1-1/+2
Fix the line longer than 80 of memory_uevent function . Signed-off-by: Wanlong Gao <wanlong.gao@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-04-23driver core: let dev_set_drvdata return int instead of void as it can failUwe Kleine-König1-4/+3
Before commit b402843 (Driver core: move dev_get/set_drvdata to drivers/base/dd.c) calling dev_set_drvdata with dev=NULL was an unchecked error. After some discussion about what to return in this case removing the check (and so producing a null pointer exception) seems fine. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-04-23driver core/platform_device_add_resources: free resource before overwritingUwe Kleine-König1-0/+1
Reviewed-by: Viresh Kumar <viresh.kumar@st.com> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-04-23driver core/platform_device_add_resources: set resource to NULL if !resUwe Kleine-König1-10/+9
This makes the res = NULL case more consistant to the res != NULL case as now both overwrite pdev->resource. Reviewed-by: Viresh Kumar <viresh.kumar@st.com> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-04-23driver core/platform_device_add_data: free platform data before overwritingUwe Kleine-König1-0/+1
Reviewed-by: Viresh Kumar <viresh.kumar@st.com> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-04-23driver core/platform_device_add_data: set platform_data to NULL if !dataUwe Kleine-König1-9/+8
This makes the data = NULL case more consistent to the data != NULL case. The functional change is that now platform_device_add_data(somepdev, NULL, somesize) sets pdev->dev.platform_data to NULL instead of not touching it. Reviewed-by: Viresh Kumar <viresh.kumar@st.com> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-04-23drivers/base/core.c: Fixed brace coding style issue.Karthigan Srinivasan1-2/+1
Fixed brace coding style issue. Signed-off-by: Karthigan Srinivasan <karthigan.srinivasan@hp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-04-23driver-core: fix race between device_register and driver_registerSebastian Ott1-0/+5
When a device is registered to a bus it will be a) added to the list of devices of the bus and b) bind to a driver (if one matches). As a result of a driver being registered at this bus between a) and b) this device could already be bound to a driver. This leads to a warning and incorrect refcounting. To fix this add a check to device_attach to identify an already bound device. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-04-20drivers: make device_type constStephen Hemminger1-2/+2
The device_type structure does not contain data that changes during usage and should be const. This allows devices to declare the struct const. I have patches to change all the subsystems, but need the infra structure change first. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-04-20PM: Add missing syscore_suspend() and syscore_resume() callsRafael J. Wysocki1-0/+2
Device suspend/resume infrastructure is used not only by the suspend and hibernate code in kernel/power, but also by APM, Xen and the kexec jump feature. However, commit 40dc166cb5dddbd36aa4ad11c03915ea (PM / Core: Introduce struct syscore_ops for core subsystems PM) failed to add syscore_suspend() and syscore_resume() calls to that code, which generally leads to breakage when the features in question are used. To fix this problem, add the missing syscore_suspend() and syscore_resume() calls to arch/x86/kernel/apm_32.c, kernel/kexec.c and drivers/xen/manage.c. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Acked-by: Ian Campbell <ian.campbell@citrix.com>
2011-04-13Merge branch 'for-linus' of ↵Linus Torvalds2-7/+7
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6: fix XEN_SAVE_RESTORE Kconfig dependencies PM / Hibernate: Introduce CONFIG_HIBERNATE_CALLBACKS
2011-04-12mfd: Fetch cell pointer from platform_device->mfd_cellSamuel Ortiz1-0/+1
In order for MFD drivers to fetch their cell pointer but also their platform data one, an mfd cell pointer is added to the platform_device structure. That allows all MFD sub devices drivers to be MFD agnostic, unless they really need to access their MFD cell data. Most of them don't, especially the ones for IPs used by both MFD and non MFD SoCs. Cc: Grant Likely <grant.likely@secretlab.ca> Acked-by: Greg KH <gregkh@suse.de> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2011-04-12PM / Hibernate: Introduce CONFIG_HIBERNATE_CALLBACKSRafael J. Wysocki2-7/+7
Xen save/restore is going to use hibernate device callbacks for quiescing devices and putting them back to normal operations and it would need to select CONFIG_HIBERNATION for this purpose. However, that also would cause the hibernate interfaces for user space to be enabled, which might confuse user space, because the Xen kernels don't support hibernation. Moreover, it would be wasteful, as it would make the Xen kernels include a substantial amount of code that they would never use. To address this issue introduce new power management Kconfig option CONFIG_HIBERNATE_CALLBACKS, such that it will only select the code that is necessary for the hibernate device callbacks to work and make CONFIG_HIBERNATION select it. Then, Xen save/restore will be able to select CONFIG_HIBERNATE_CALLBACKS without dragging the entire hibernate code along with it. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Tested-by: Shriram Rajagopalan <rshriram@cs.ubc.ca>
2011-04-10sysfs-memory: fix uninitialized variable warning and clean-up code.Nikanth Karthikesan1-5/+4
sysfs-memory: Fix uninitialized variable warning and clean-up code. Signed-off-by: Nikanth Karthikesan <knikanth@suse.de> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-03-31Fix common misspellingsLucas De Marchi2-8/+8
Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-24Introduce ARCH_NO_SYSDEV_OPS config option (v2)Rafael J. Wysocki2-1/+9
Introduce Kconfig option allowing architectures where sysdev operations used during system suspend, resume and shutdown have been completely replaced with struct sycore_ops operations to avoid building sysdev code that will never be used. Make callbacks in struct sys_device and struct sysdev_driver depend on ARCH_NO_SYSDEV_OPS to allows us to verify if all of the references have been actually removed from the code the given architecture depends on. Make x86 select ARCH_NO_SYSDEV_OPS. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-03-17Merge branch 'driver-core-next' of ↵Linus Torvalds5-83/+232
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6 * 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6: (50 commits) printk: do not mangle valid userspace syslog prefixes efivars: Add Documentation efivars: Expose efivars functionality to external drivers. efivars: Parameterize operations. efivars: Split out variable registration efivars: parameterize efivars efivars: Make efivars bin_attributes dynamic efivars: move efivars globals into struct efivars drivers:misc: ti-st: fix debugging code kref: Fix typo in kref documentation UIO: add PRUSS UIO driver support Fix spelling mistakes in Documentation/zh_CN/SubmittingPatches firmware: Fix unaligned memory accesses in dmi-sysfs firmware: Add documentation for /sys/firmware/dmi firmware: Expose DMI type 15 System Event Log firmware: Break out system_event_log in dmi-sysfs firmware: Basic dmi-sysfs support firmware: Add DMI entry types to the headers Driver core: convert platform_{get,set}_drvdata to static inline functions Translate linux-2.6/Documentation/magic-number.txt into Chinese ...
2011-03-15PM / Core: Introduce struct syscore_ops for core subsystems PMRafael J. Wysocki2-1/+118
Some subsystems need to carry out suspend/resume and shutdown operations with one CPU on-line and interrupts disabled. The only way to register such operations is to define a sysdev class and a sysdev specifically for this purpose which is cumbersome and inefficient. Moreover, the arguments taken by sysdev suspend, resume and shutdown callbacks are practically never necessary. For this reason, introduce a simpler interface allowing subsystems to register operations to be executed very late during system suspend and shutdown and very early during resume in the form of strcut syscore_ops objects. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-03-15PM / OPP: opp_find_freq_exact() documentation fixNishanth Menon1-1/+1
opp_find_freq_exact() documentation has is_available instead of available. This also fixes warning with the kernel-doc: scripts/kernel-doc drivers/base/power/opp.c >/dev/null Warning(drivers/base/power/opp.c:246): No description found for parameter 'available' Warning(drivers/base/power/opp.c:246): Excess function parameter 'is_available' description in 'opp_find_freq_exact' Signed-off-by: Nishanth Menon <nm@ti.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-03-15PM: Make system-wide PM and runtime PM treat subsystems consistentlyRafael J. Wysocki2-95/+73
The code handling system-wide power transitions (eg. suspend-to-RAM) can in theory execute callbacks provided by the device's bus type, device type and class in each phase of the power transition. In turn, the runtime PM core code only calls one of those callbacks at a time, preferring bus type callbacks to device type or class callbacks and device type callbacks to class callbacks. It seems reasonable to make them both behave in the same way in that respect. Moreover, even though a device may belong to two subsystems (eg. bus type and device class) simultaneously, in practice power management callbacks for system-wide power transitions are always provided by only one of them (ie. if the bus type callbacks are defined, the device class ones are not and vice versa). Thus it is possible to modify the code handling system-wide power transitions so that it follows the core runtime PM code (ie. treats the subsystem callbacks as mutually exclusive). On the other hand, the core runtime PM code will choose to execute, for example, a runtime suspend callback provided by the device type even if the bus type's struct dev_pm_ops object exists, but the runtime_suspend pointer in it happens to be NULL. This is confusing, because it may lead to the execution of callbacks from different subsystems during different operations (eg. the bus type suspend callback may be executed during runtime suspend of the device, while the device type callback will be executed during system suspend). Make all of the power management code treat subsystem callbacks in a consistent way, such that: (1) If the device's type is defined (eg. dev->type is not NULL) and its pm pointer is not NULL, the callbacks from dev->type->pm will be used. (2) If dev->type is NULL or dev->type->pm is NULL, but the device's class is defined (eg. dev->class is not NULL) and its pm pointer is not NULL, the callbacks from dev->class->pm will be used. (3) If dev->type is NULL or dev->type->pm is NULL and dev->class is NULL or dev->class->pm is NULL, the callbacks from dev->bus->pm will be used provided that both dev->bus and dev->bus->pm are not NULL. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Kevin Hilman <khilman@ti.com> Reasoning-sounds-sane-to: Grant Likely <grant.likely@secretlab.ca> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-03-15PM: Add support for device power domainsRafael J. Wysocki2-2/+54
The platform bus type is often used to handle Systems-on-a-Chip (SoC) where all devices are represented by objects of type struct platform_device. In those cases the same "platform" device driver may be used with multiple different system configurations, but the actions needed to put the devices it handles into a low-power state and back into the full-power state may depend on the design of the given SoC. The driver, however, cannot possibly include all the information necessary for the power management of its device on all the systems it is used with. Moreover, the device hierarchy in its current form also is not suitable for representing this kind of information. The patch below attempts to address this problem by introducing objects of type struct dev_power_domain that can be used for representing power domains within a SoC. Every struct dev_power_domain object provides a sets of device power management callbacks that can be used to perform what's needed for device power management in addition to the operations carried out by the device's driver and subsystem. Namely, if a struct dev_power_domain object is pointed to by the pwr_domain field in a struct device, the callbacks provided by its ops member will be executed in addition to the corresponding callbacks provided by the device's subsystem and driver during all power transitions. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Tested-and-acked-by: Kevin Hilman <khilman@ti.com>
2011-03-15PM: Allow pm_runtime_suspend() to succeed during system suspendRafael J. Wysocki1-7/+3
The dpm_prepare() function increments the runtime PM reference counters of all devices to prevent pm_runtime_suspend() from executing subsystem-level callbacks. However, this was supposed to guard against a specific race condition that cannot happen, because the power management workqueue is freezable, so pm_runtime_suspend() can only be called synchronously during system suspend and we can rely on subsystems and device drivers to avoid doing that unnecessarily. Make dpm_prepare() drop the runtime PM reference to each device after making sure that runtime resume is not pending for it. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Kevin Hilman <khilman@ti.com>
2011-03-15PM: Remove CONFIG_PM_OPSRafael J. Wysocki1-2/+1
After redefining CONFIG_PM to depend on (CONFIG_PM_SLEEP || CONFIG_PM_RUNTIME) the CONFIG_PM_OPS option is redundant and can be replaced with CONFIG_PM. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-03-15PM: Do not create wakeup sysfs files for devices that cannot wake upRafael J. Wysocki3-38/+90
Currently, wakeup sysfs attributes are created for all devices, regardless of whether or not they are wakeup-capable. This is excessive and complicates wakeup device identification from user space (i.e. to identify wakeup-capable devices user space has to read /sys/devices/.../power/wakeup for all devices and see if they are not empty). Fix this issue by avoiding to create wakeup sysfs files for devices that cannot wake up the system from sleep states (i.e. whose power.can_wakeup flags are unset during registration) and modify device_set_wakeup_capable() so that it adds (or removes) the relevant sysfs attributes if a device's wakeup capability status is changed. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-03-15PM: Use appropriate printk() priority level in trace.cMandeep Singh Baines1-3/+3
printk()s without a priority level default to KERN_WARNING. To reduce noise at KERN_WARNING, this patch sets the priority level appriopriately for unleveled printks()s. This should be useful to folks that look at dmesg warnings closely. Changed these messages to pr_info(). Signed-off-by: Mandeep Singh Baines <msb@chromium.org> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-03-15PM / Wakeup: Don't update events_check_enabled in pm_get_wakeup_count()Rafael J. Wysocki1-5/+2
Since pm_save_wakeup_count() has just been changed to clear events_check_enabled unconditionally before checking if there are any new wakeup events registered since the last read from /sys/power/wakeup_count, the detection of wakeup events during suspend may be disabled, after it's been enabled, by writing a "wrong" value back to /sys/power/wakeup_count. For this reason, it is not necessary to update events_check_enabled in pm_get_wakeup_count() any more. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-03-15PM / Wakeup: Make pm_save_wakeup_count() work as documentedRafael J. Wysocki1-6/+6
According to Documentation/ABI/testing/sysfs-power, the /sys/power/wakeup_count interface should only make the kernel react to wakeup events during suspend if the last write to it has been successful. However, if /sys/power/wakeup_count is written to two times in a row, where the first write is successful and the second is not, the kernel will still react to wakeup events during suspend due to a bug in pm_save_wakeup_count(). Fix the bug by making pm_save_wakeup_count() clear events_check_enabled unconditionally before checking if there are any new wakeup events registered since the previous read from /sys/power/wakeup_count. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-03-15PM / Wakeup: Combine atomic counters to avoid reordering issuesRafael J. Wysocki1-22/+39
The memory barrier in wakeup_source_deactivate() is supposed to prevent the callers of pm_wakeup_pending() and pm_get_wakeup_count() from seeing the new value of events_in_progress (0, in particular) and the old value of event_count at the same time. However, if wakeup_source_deactivate() is executed by CPU0 and, for instance, pm_wakeup_pending() is executed by CPU1, where both processors can reorder operations, the memory barrier in wakeup_source_deactivate() doesn't affect CPU1 which can reorder reads. In that case CPU1 may very well decide to fetch event_count before it's modified and events_in_progress after it's been updated, so pm_wakeup_pending() may fail to detect a wakeup event. This issue can be addressed by using a single atomic variable to store both events_in_progress and event_count, so that they can be updated together in a single atomic operation. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-02-04driver core: Replace the dangerous to_root_device macro with an inline functionFerenc Wagner1-1/+4
The original macro worked only when applied to variables named 'dev'. While this could have been fixed by simply renaming the macro argument, a more type-safe replacement by an inline function is preferred. Signed-off-by: Ferenc Wagner <wferi@niif.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-02-04memory hotplug: sysfs probe routine should add all memory sectionsNathan Fontenot1-3/+10
As a follow-on to the recent patches I submitted that allowed for a sysfs memory block to span multiple memory sections, we should also update the probe routine to online all of the memory sections in a memory block. Without this patch the current code will only add a single memory section. I think the probe routine should add all of the memory sections in the specified memory block so that its behavior is in line with memory hotplug actions through the sysfs interfaces. This patch applies on top of the previous sysfs memory updates to allow a sysfs directory o span multiple memory sections. https://lkml.org/lkml/2011/1/20/245 Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>