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2013-12-08Revert "cpufreq: suspend governors on system suspend/hibernate"Rafael J. Wysocki1-3/+0
Commit 5a87182aa21d (cpufreq: suspend governors on system suspend/hibernate) causes hibernation problems to happen on Bjørn Mork's and Paul Bolle's systems, so revert it. Fixes: 5a87182aa21d (cpufreq: suspend governors on system suspend/hibernate) Reported-by: Bjørn Mork <bjorn@mork.no> Reported-by: Paul Bolle <pebolle@tiscali.nl> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-12-06Merge branches 'pm-cpuidle' and 'pm-cpufreq'Rafael J. Wysocki1-0/+3
* pm-cpuidle: cpuidle: Check for dev before deregistering it. intel_idle: Fixed C6 state on Avoton/Rangeley processors * pm-cpufreq: cpufreq: fix garbage kobjects on errors during suspend/resume cpufreq: suspend governors on system suspend/hibernate
2013-11-28cpufreq: suspend governors on system suspend/hibernateViresh Kumar1-0/+3
This patch adds cpufreq suspend/resume calls to dpm_{suspend|resume}_noirq() for handling suspend/resume of cpufreq governors. Lan Tianyu (Intel) & Jinhyuk Choi (Broadcom) found anr issue where tunables configuration for clusters/sockets with non-boot CPUs was getting lost after suspend/resume, as we were notifying governors with CPUFREQ_GOV_POLICY_EXIT on removal of the last cpu for that policy and so deallocating memory for tunables. This is fixed by this patch as we don't allow any operation on governors after device suspend and before device resume now. Reported-and-tested-by: Lan Tianyu <tianyu.lan@intel.com> Reported-by: Jinhyuk Choi <jinchoi@broadcom.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> [rjw: Changelog, minor cleanups] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-11-20Merge tag 'pm+acpi-2-3.13-rc1' of ↵Linus Torvalds1-0/+3
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull more ACPI and power management updates from Rafael Wysocki: - ACPI-based device hotplug fixes for issues introduced recently and a fix for an older error code path bug in the ACPI PCI host bridge driver - Fix for recently broken OMAP cpufreq build from Viresh Kumar - Fix for a recent hibernation regression related to s2disk - Fix for a locking-related regression in the ACPI EC driver from Puneet Kumar - System suspend error code path fix related to runtime PM and runtime PM documentation update from Ulf Hansson - cpufreq's conservative governor fix from Xiaoguang Chen - New processor IDs for intel_idle and turbostat and removal of an obsolete Kconfig option from Len Brown - New device IDs for the ACPI LPSS (Low-Power Subsystem) driver and ACPI-based PCI hotplug (ACPIPHP) cleanup from Mika Westerberg - Removal of several ACPI video DMI blacklist entries that are not necessary any more from Aaron Lu - Rework of the ACPI companion representation in struct device and code cleanup related to that change from Rafael J Wysocki, Lan Tianyu and Jarkko Nikula - Fixes for assigning names to ACPI-enumerated I2C and SPI devices from Jarkko Nikula * tag 'pm+acpi-2-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (24 commits) PCI / hotplug / ACPI: Drop unused acpiphp_debug declaration ACPI / scan: Set flags.match_driver in acpi_bus_scan_fixed() ACPI / PCI root: Clear driver_data before failing enumeration ACPI / hotplug: Fix PCI host bridge hot removal ACPI / hotplug: Fix acpi_bus_get_device() return value check cpufreq: governor: Remove fossil comment in the cpufreq_governor_dbs() ACPI / video: clean up DMI table for initial black screen problem ACPI / EC: Ensure lock is acquired before accessing ec struct members PM / Hibernate: Do not crash kernel in free_basic_memory_bitmaps() ACPI / AC: Remove struct acpi_device pointer from struct acpi_ac spi: Use stable dev_name for ACPI enumerated SPI slaves i2c: Use stable dev_name for ACPI enumerated I2C slaves ACPI: Provide acpi_dev_name accessor for struct acpi_device device name ACPI / bind: Use (put|get)_device() on ACPI device objects too ACPI: Eliminate the DEVICE_ACPI_HANDLE() macro ACPI / driver core: Store an ACPI device pointer in struct acpi_dev_node cpufreq: OMAP: Fix compilation error 'r & ret undeclared' PM / Runtime: Fix error path for prepare PM / Runtime: Update documentation around probe|remove|suspend cpufreq: conservative: set requested_freq to policy max when it is over policy max ...
2013-11-19Merge branch 'pm-runtime'Rafael J. Wysocki1-0/+3
* pm-runtime: PM / Runtime: Fix error path for prepare PM / Runtime: Update documentation around probe|remove|suspend
2013-11-15tree-wide: use reinit_completion instead of INIT_COMPLETIONWolfram Sang1-2/+2
Use this new function to make code more comprehensible, since we are reinitialzing the completion, not initializing. [akpm@linux-foundation.org: linux-next resyncs] Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Acked-by: Linus Walleij <linus.walleij@linaro.org> (personally at LCE13) Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-14PM / Runtime: Fix error path for prepareUlf Hansson1-0/+3
If a device prepare callback for some reason would fail, the PM core prevented the device from going inactive forever. In this case, to reverse the pm_runtime_get_noresume() we invokes the asyncronous pm_runtime_put(), thus restoring the usage count. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-18PM / Sleep: Detect device suspend/resume lockup and log eventBenoit Goby1-0/+73
Rather than hard-lock the kernel, dump the suspend/resume thread stack and panic() to capture a message in pstore when a driver takes too long to suspend/resume. Default suspend/resume watchdog timeout is set to 12 seconds to be longer than the usbhid 10 second timeout, but could be changed at compile time. Exclude from the watchdog the time spent waiting for children that are resumed asynchronously and time every device, whether or not they resumed synchronously. This patch is targeted for mobile devices where a suspend/resume lockup could cause a system reboot. Information about failing device can be retrieved in subsequent boot session by mounting pstore and inspecting the log. Laptops with EFI-enabled pstore could also benefit from this feature. The hardware watchdog timer is likely suspended during this time and couldn't be relied upon. The soft-lockup detector would eventually tell that tasks are not scheduled, but would provide little context as to why. The patch hence uses system timer and assumes it is still active while the devices are suspended/resumed. This feature can be enabled/disabled during kernel configuration. This change is based on earlier work by San Mehat. Signed-off-by: Benoit Goby <benoit@android.com> Signed-off-by: Zoran Markovic <zoran.markovic@linaro.org> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-27PM / Sleep: new trace event to print device suspend and resume timesShuah Khan1-34/+43
A new trace event is added to PM events to print the time it takes to suspend and resume a device. It generates trace messages that include device, driver, parent information in addition to the type of PM ops invoked as well as the PM event and error status from the PM ops. Example trace below: bash-2239 [000] .... 290.883035: device_pm_report_time: backlight acpi_video0 parent=0000:00:02.0 state=freeze ops=class nsecs=332 err=0 bash-2239 [000] .... 290.883041: device_pm_report_time: rfkill rf kill3 parent=phy0 state=freeze ops=legacy class nsecs=216 err=0 bash-2239 [001] .... 290.973892: device_pm_report_time: ieee80211 phy0 parent=0000:01:00.0 state=freeze ops=legacy class nsecs=90846477 err=0 bash-2239 [001] .... 293.660129: device_pm_report_time: ieee80211 phy0 parent=0000:01:00.0 state=restore ops=legacy class nsecs=101295162 err=0 bash-2239 [001] .... 293.660147: device_pm_report_time: rfkill rfkill3 parent=phy0 state=restore ops=legacy class nsecs=1804 err=0 bash-2239 [001] .... 293.660157: device_pm_report_time: backlight acpi_video0 parent=0000:00:02.0 state=restore ops=class nsecs=757 err=0 Signed-off-by: Shuah Khan <shuah.kh@samsung.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-12PM / Runtime: Asyncronous idle|suspend devices at system resumeUlf Hansson1-1/+1
Use the asyncronous runtime PM API when returning the runtime reference for the device after the system resume is completed. By using the asyncronous runtime PM API we don't have to wait for each an every device to become idle|suspended. Instead we can move on and handle the next device in queue. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-03-04PM / QoS: Remove device PM QoS sysfs attributes at the right placeRafael J. Wysocki1-2/+0
Device PM QoS sysfs attributes, if present during device removal, are removed from within device_pm_remove(), which is too late, since dpm_sysfs_remove() has already removed the whole attribute group they belonged to. However, moving the removal of those attributes to dpm_sysfs_remove() alone is not sufficient, because in theory they still can be re-added right after being removed by it (the device's driver is still bound to it at that point). For this reason, move the entire desctruction of device PM QoS constraints to dpm_sysfs_remove() and make it prevent any new constraints from being added after it has run. Also, move the initialization of the power.qos field in struct device to device_pm_init_common() and drop the no longer needed dev_pm_qos_constraints_init(). Reported-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-01-06PM: Move disabling/enabling runtime PM to late suspend/early resumeRafael J. Wysocki1-5/+4
Currently, the PM core disables runtime PM for all devices right after executing subsystem/driver .suspend() callbacks for them and re-enables it right before executing subsystem/driver .resume() callbacks for them. This may lead to problems when there are two devices such that the .suspend() callback executed for one of them depends on runtime PM working for the other. In that case, if runtime PM has already been disabled for the second device, the first one's .suspend() won't work correctly (and analogously for resume). To make those issues go away, make the PM core disable runtime PM for devices right before executing subsystem/driver .suspend_late() callbacks for them and enable runtime PM for them right after executing subsystem/driver .resume_early() callbacks for them. This way the potential conflitcs between .suspend_late()/.resume_early() and their runtime PM counterparts are still prevented from happening, but the subtle ordering issues related to disabling/enabling runtime PM for devices during system suspend/resume are much easier to avoid. Reported-and-tested-by: Jan-Matthias Braun <jan_braun@gmx.net> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Kevin Hilman <khilman@deeprootsystems.com> Cc: 3.4+ <stable@vger.kernel.org>
2012-10-02Merge tag 'pm-for-3.7-rc1' of ↵Linus Torvalds1-17/+49
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael J Wysocki: - Improved system suspend/resume and runtime PM handling for the SH TMU, CMT and MTU2 clock event devices (also used by ARM/shmobile). - Generic PM domains framework extensions related to cpuidle support and domain objects lookup using names. - ARM/shmobile power management updates including improved support for the SH7372's A4S power domain containing the CPU core. - cpufreq changes related to AMD CPUs support from Matthew Garrett, Andre Przywara and Borislav Petkov. - cpu0 cpufreq driver from Shawn Guo. - cpufreq governor fixes related to the relaxing of limit from Michal Pecio. - OMAP cpufreq updates from Axel Lin and Richard Zhao. - cpuidle ladder governor fixes related to the disabling of states from Carsten Emde and me. - Runtime PM core updates related to the interactions with the system suspend core from Alan Stern and Kevin Hilman. - Wakeup sources modification allowing more helper functions to be called from interrupt context from John Stultz and additional diagnostic code from Todd Poynor. - System suspend error code path fix from Feng Hong. Fixed up conflicts in cpufreq/powernow-k8 that stemmed from the workqueue fixes conflicting fairly badly with the removal of support for hardware P-state chips. The changes were independent but somewhat intertwined. * tag 'pm-for-3.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (76 commits) Revert "PM QoS: Use spinlock in the per-device PM QoS constraints code" PM / Runtime: let rpm_resume() succeed if RPM_ACTIVE, even when disabled, v2 cpuidle: rename function name "__cpuidle_register_driver", v2 cpufreq: OMAP: Check IS_ERR() instead of NULL for omap_device_get_by_hwmod_name cpuidle: remove some empty lines PM: Prevent runtime suspend during system resume PM QoS: Use spinlock in the per-device PM QoS constraints code PM / Sleep: use resume event when call dpm_resume_early cpuidle / ACPI : move cpuidle_device field out of the acpi_processor_power structure ACPI / processor: remove pointless variable initialization ACPI / processor: remove unused function parameter cpufreq: OMAP: remove loops_per_jiffy recalculate for smp sections: fix section conflicts in drivers/cpufreq cpufreq: conservative: update frequency when limits are relaxed cpufreq / ondemand: update frequency when limits are relaxed properly __init-annotate pm_sysrq_init() cpufreq: Add a generic cpufreq-cpu0 driver PM / OPP: Initialize OPP table from device tree ARM: add cpufreq transiton notifier to adjust loops_per_jiffy for smp cpufreq: Remove support for hardware P-state chips from powernow-k8 ...
2012-09-24Merge branch 'pm-sleep'Rafael J. Wysocki1-12/+19
* pm-sleep: PM: Prevent runtime suspend during system resume PM / Sleep: use resume event when call dpm_resume_early Conflicts: drivers/base/power/main.c (trivial)
2012-09-19PM: Prevent runtime suspend during system resumeAlan Stern1-11/+18
This patch (as1591) moves the pm_runtime_get_noresume() and pm_runtime_put_sync() calls from __device_suspend() and device_resume() to device_prepare() and device_complete() in the PM core. The reason for doing this is to make sure that parent devices remain at full power (i.e., don't go into runtime suspend) while their children are being resumed from a system sleep. The PCI core already contained equivalent code to serve the same purpose. The patch removes the duplicated code, since it is no longer needed. One of the comments from the PCI core gets moved into the PM core, and a second comment is added to explain whe the _get_noresume and _put_sync calls are present. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-09-19PM / Sleep: use resume event when call dpm_resume_earlyFeng Hong1-1/+1
When dpm_suspend_noirq fail, state is PMSG_SUSPEND, should change to PMSG_RESUME when dpm_resume_early is called Signed-off-by: Feng Hong <hongfeng@marvell.com> Signed-off-by: Raul Xiong <xjian@marvell.com> Signed-off-by: Neil Zhang <zhangwm@marvell.com> Cc: stable@vger.kernel.org Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-09-04PM / Domains: Move syscore flag from subsys data to struct deviceRafael J. Wysocki1-0/+28
The syscore device PM flag is used to mark the devices (belonging to a PM domain) that should never be turned off, except for the system core (syscore) suspend/hibernation and resume stages. That flag is stored in the device's struct pm_subsys_data object whose address is available from struct device. However, in some situations it may be convenient to set that flag before the device is added to a PM domain, so it is better to move it directly to the "power" member of struct device. Then, it can be checked by the routines in drivers/base/power/runtime.c and drivers/base/power/main.c, which is more straightforward. This also reduces the number of dev_gpd_data() invocations in the generic PM domains framework, so the overhead related to the syscore flag is slightly smaller. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Magnus Damm <damm@opensource.se>
2012-09-04PM: Reorganize device PM initializationRafael J. Wysocki1-5/+2
Make the device power management initialization more straightforward by moving the initialization of common (i.e. used by both runtime PM and system suspend) fields to a separate routine. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-08-17PM / Sleep: introduce dpm_for_each_devMing Lei1-0/+22
dpm_list and its pm lock provide a good way to iterate all devices in system. Except this way, there is no other easy way to iterate devices in system. firmware loader need to cache firmware images for devices before system sleep, so introduce the function to meet its demand. Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-19Merge branch 'pm-sleep'Rafael J. Wysocki1-1/+9
* pm-sleep: PM / Sleep: call early resume handlers when suspend_noirq fails
2012-07-19PM / Sleep: call early resume handlers when suspend_noirq failsColin Cross1-1/+9
Commit cf579dfb82550e34de7ccf3ef090d8b834ccd3a9 (PM / Sleep: Introduce "late suspend" and "early resume" of devices) introduced a bug where suspend_late handlers would be called, but if dpm_suspend_noirq returned an error the early_resume handlers would never be called. All devices would end up on the dpm_late_early_list, and would never be resumed again. Fix it by calling dpm_resume_early when dpm_suspend_noirq returns an error. Signed-off-by: Colin Cross <ccross@android.com> Cc: stable@vger.kernel.org Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-07-19Merge branch 'pm-sleep'Rafael J. Wysocki1-6/+6
* pm-sleep: PM / Sleep: Require CAP_BLOCK_SUSPEND to use wake_lock/wake_unlock PM / Sleep: Add missing static storage class specifiers in main.c PM / Sleep: Fix build warning in sysfs.c for CONFIG_PM_SLEEP unset PM / Hibernate: Print hibernation/thaw progress indicator one line at a time. PM / Sleep: Separate printing suspend times from initcall_debug PM / Sleep: add knob for printing device resume times ftrace: Disable function tracing during suspend/resume and hibernation, again PM / Hibernate: Enable suspend to both for in-kernel hibernation.
2012-07-18PM / Sleep: Add missing static storage class specifiers in main.cSachin Kamat1-4/+4
Fix the following sparse warnings: drivers/base/power/main.c:48:1: warning: symbol 'dpm_prepared_list' was not declared. Should it be static? drivers/base/power/main.c:49:1: warning: symbol 'dpm_suspended_list' was not declared. Should it be static? drivers/base/power/main.c:50:1: warning: symbol 'dpm_late_early_list' was not declared. Should it be static? drivers/base/power/main.c:51:1: warning: symbol 'dpm_noirq_list' was not declared. Should it be static? Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-07-10PM / cpuidle: System resume hang fix with cpuidlePreeti U Murthy1-1/+3
On certain bios, resume hangs if cpus are allowed to enter idle states during suspend [1]. This was fixed in apci idle driver [2].But intel_idle driver does not have this fix. Thus instead of replicating the fix in both the idle drivers, or in more platform specific idle drivers if needed, the more general cpuidle infrastructure could handle this. A suspend callback in cpuidle_driver could handle this fix. But a cpuidle_driver provides only basic functionalities like platform idle state detection capability and mechanisms to support entry and exit into CPU idle states. All other cpuidle functions are found in the cpuidle generic infrastructure for good reason that all cpuidle drivers, irrepective of their platforms will support these functions. One option therefore would be to register a suspend callback in cpuidle which handles this fix. This could be called through a PM_SUSPEND_PREPARE notifier. But this is too generic a notfier for a driver to handle. Also, ideally the job of cpuidle is not to handle side effects of suspend. It should expose the interfaces which "handle cpuidle 'during' suspend" or any other operation, which the subsystems call during that respective operation. The fix demands that during suspend, no cpus should be allowed to enter deep C-states. The interface cpuidle_uninstall_idle_handler() in cpuidle ensures that. Not just that it also kicks all the cpus which are already in idle out of their idle states which was being done during cpu hotplug through a CPU_DYING_FROZEN callbacks. Now the question arises about when during suspend should cpuidle_uninstall_idle_handler() be called. Since we are dealing with drivers it seems best to call this function during dpm_suspend(). Delaying the call till dpm_suspend_noirq() does no harm, as long as it is before cpu_hotplug_begin() to avoid race conditions with cpu hotpulg operations. In dpm_suspend_noirq(), it would be wise to place this call before suspend_device_irqs() to avoid ugly interactions with the same. Ananlogously, during resume. References: [1] https://bugs.launchpad.net/ubuntu/+source/linux/+bug/674075. [2] http://marc.info/?l=linux-pm&m=133958534231884&w=2 Reported-and-tested-by: Dave Hansen <dave@linux.vnet.ibm.com> Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com> Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-07-01PM / Sleep: Separate printing suspend times from initcall_debugRafael J. Wysocki1-2/+2
Change the behavior of the newly introduced /sys/power/pm_print_times attribute so that its initial value depends on initcall_debug, but setting it to 0 will cause device suspend/resume times not to be printed, even if initcall_debug has been set. This way, the people who use initcall_debug for reasons other than PM debugging will be able to switch the suspend/resume times printing off, if need be. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-01PM / Sleep: add knob for printing device resume timesSameer Nanda1-2/+2
Added a new knob called /sys/power/pm_print_times. Setting it to 1 enables printing of time taken by devices to suspend and resume. Setting it to 0 disables this printing (unless overridden by initcall_debug kernel command line option). Signed-off-by: Sameer Nanda <snanda@chromium.org> Acked-by: Greg KH <gregkh@linuxfoundation.org> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-06-24PM / Sleep: Prevent waiting forever on asynchronous suspend after abortMandeep Singh Baines1-2/+4
__device_suspend() must always send a completion. Otherwise, parent devices will wait forever. Commit 1e2ef05b, "PM: Limit race conditions between runtime PM and system sleep (v2)", introduced a regression by short-circuiting the complete_all() for certain error cases. This patch fixes the bug by always signalling a completion. Addresses http://crosbug.com/31972 Tested by injecting an abort. Signed-off-by: Mandeep Singh Baines <msb@chromium.org> Cc: stable@vger.kernel.org Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-05-01PM / Sleep: Look for wakeup events in later stages of device suspendRafael J. Wysocki1-0/+10
Currently, the device suspend code in drivers/base/power/main.c only checks if there have been any wakeup events, and therefore the ongoing system transition to a sleep state should be aborted, during the first (i.e. "suspend") device suspend phase. However, wakeup events may be reported later as well, so it's reasonable to look for them in the in the subsequent (i.e. "late suspend" and "suspend noirq") phases. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-01-29PM / Sleep: Introduce "late suspend" and "early resume" of devicesRafael J. Wysocki1-22/+225
The current device suspend/resume phases during system-wide power transitions appear to be insufficient for some platforms that want to use the same callback routines for saving device states and related operations during runtime suspend/resume as well as during system suspend/resume. In principle, they could point their .suspend_noirq() and .resume_noirq() to the same callback routines as their .runtime_suspend() and .runtime_resume(), respectively, but at least some of them require device interrupts to be enabled while the code in those routines is running. It also makes sense to have device suspend-resume callbacks that will be executed with runtime PM disabled and with device interrupts enabled in case someone needs to run some special code in that context during system-wide power transitions. Apart from this, .suspend_noirq() and .resume_noirq() were introduced as a workaround for drivers using shared interrupts and failing to prevent their interrupt handlers from accessing suspended hardware. It appears to be better not to use them for other porposes, or we may have to deal with some serious confusion (which seems to be happening already). For the above reasons, introduce new device suspend/resume phases, "late suspend" and "early resume" (and analogously for hibernation) whose callback will be executed with runtime PM disabled and with device interrupts enabled and whose callback pointers generally may point to runtime suspend/resume routines. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Reviewed-by: Kevin Hilman <khilman@ti.com>
2011-12-21PM: Run the driver callback directly if the subsystem one is not thereRafael J. Wysocki1-37/+72
Make the PM core execute driver PM callbacks directly if the corresponding subsystem callbacks are not present. There are three reasons for doing that. First, it reflects the behavior of drivers/base/dd.c:really_probe() that runs the driver's .probe() callback directly if the bus type's one is not defined, so this change will remove one arbitrary difference between the PM core and the remaining parts of the driver core. Second, it will allow some subsystems, whose PM callbacks don't do anything except for executing driver callbacks, to be simplified quite a bit by removing those "forward-only" callbacks. Finally, it will allow us to remove one level of indirection in the system suspend and resume code paths where it is not necessary, which is going to lead to less debug noise with initcall_debug passed in the kernel command line (messages won't be printed for driverless devices whose subsystems don't provide PM callbacks among other things). Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-12-21PM / Sleep: Make pm_op() and pm_noirq_op() return callback pointersRafael J. Wysocki1-102/+95
Make the pm_op() and pm_noirq_op() functions return pointers to appropriate callbacks instead of executing those callbacks and returning their results. This change is required for a subsequent modification that will execute the corresponding driver callback if the subsystem callback returned by either pm_op(), or pm_noirq_op() is NULL. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-12-06PM / Sleep: Unify diagnostic messages from device suspend/resumeRafael J. Wysocki1-93/+35
Make pm_op() and pm_noirq_op() use the same helper function for running callbacks, which will cause them to use the same format of diagnostic messages. This also reduces the complexity and size of the code quite a bit. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-23PM / Sleep: Simplify device_suspend_noirq()Rafael J. Wysocki1-10/+2
Remove a few if () and return statements in device_suspend_noirq() that aren't really necessary. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
2011-11-23PM / Sleep: Remove unnecessary label and jumps to it form PM core codeRafael J. Wysocki1-7/+0
The "End" label in device_prepare() in drivers/base/power/main.c is not necessary and the jumps to it have no real effect, so remove them all. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
2011-11-17PM Sleep: Do not extend wakeup paths to devices with ignore_children setRafael J. Wysocki1-1/+2
Commit 4ca46ff3e0d8c234cb40ebb6457653b59584426c (PM / Sleep: Mark devices involved in wakeup signaling during suspend) introduced the power.wakeup_path field in struct dev_pm_info to mark devices whose children are enabled to wake up the system from sleep states, so that power domains containing the parents that provide their children with wakeup power and/or relay their wakeup signals are not turned off. Unfortunately, that introduced a PM regression on SH7372 whose power consumption in the system "memory sleep" state increased as a result of it, because it prevented the power domain containing the I2C controller from being turned off when some children of that controller were enabled to wake up the system, although the controller was not necessary for them to signal wakeup. To fix this issue use the observation that devices whose power.ignore_children flag is set for runtime PM should be treated analogously during system suspend. Namely, they shouldn't be included in wakeup paths going through their children. Since the SH7372 I2C controller's power.ignore_children flag is set, doing so will restore the previous behavior of that SOC. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-10-31drivers/base: Add export.h for EXPORT_SYMBOL/THIS_MODULE as required.Paul Gortmaker1-0/+1
Most of these files were implicitly getting EXPORT_SYMBOL via device.h which was including module.h, but that path will be broken soon. [ with input from Stephen Rothwell <sfr@canb.auug.org.au> ] Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-22Merge branch 'pm-domains' into pm-for-linusRafael J. Wysocki1-1/+7
* pm-domains: ARM: mach-shmobile: sh7372 A4R support (v4) ARM: mach-shmobile: sh7372 A3SP support (v4) PM / Sleep: Mark devices involved in wakeup signaling during suspend
2011-10-22PM / Sleep: Mark devices involved in wakeup signaling during suspendRafael J. Wysocki1-1/+7
The generic PM domains code in drivers/base/power/domain.c has to avoid powering off domains that provide power to wakeup devices during system suspend. Currently, however, this only works for wakeup devices directly belonging to the given domain and not for their children (or the children of their children and so on). Thus, if there's a wakeup device whose parent belongs to a power domain handled by the generic PM domains code, the domain will be powered off during system suspend preventing the device from signaling wakeup. To address this problem introduce a device flag, power.wakeup_path, that will be set during system suspend for all wakeup devices, their parents, the parents of their parents and so on. This way, all wakeup paths in the device hierarchy will be marked and the generic PM domains code will only need to avoid powering off domains containing devices whose power.wakeup_path is set. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-10-16PM / Suspend: Add statistics debugfs file for suspend to RAMShuoX Liu1-5/+26
Record S3 failure time about each reason and the latest two failed devices' names in S3 progress. We can check it through 'suspend_stats' entry in debugfs. The motivation of the patch: We are enabling power features on Medfield. Comparing with PC/notebook, a mobile enters/exits suspend-2-ram (we call it s3 on Medfield) far more frequently. If it can't enter suspend-2-ram in time, the power might be used up soon. We often find sometimes, a device suspend fails. Then, system retries s3 over and over again. As display is off, testers and developers don't know what happens. Some testers and developers complain they don't know if system tries suspend-2-ram, and what device fails to suspend. They need such info for a quick check. The patch adds suspend_stats under debugfs for users to check suspend to RAM statistics quickly. If not using this patch, we have other methods to get info about what device fails. One is to turn on CONFIG_PM_DEBUG, but users would get too much info and testers need recompile the system. In addition, dynamic debug is another good tool to dump debug info. But it still doesn't match our utilization scenario closely. 1) user need write a user space parser to process the syslog output; 2) Our testing scenario is we leave the mobile for at least hours. Then, check its status. No serial console available during the testing. One is because console would be suspended, and the other is serial console connecting with spi or HSU devices would consume power. These devices are powered off at suspend-2-ram. Signed-off-by: ShuoX Liu <shuox.liu@intel.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-10-04PM / QoS: Add function dev_pm_qos_read_value() (v3)Rafael J. Wysocki1-3/+3
To read the current PM QoS value for a given device we need to make sure that the device's power.constraints object won't be removed while we're doing that. For this reason, put the operation under dev->power.lock and acquire the lock around the initialization and removal of power.constraints. Moreover, since we're using the value of power.constraints to determine whether or not the object is present, the power.constraints_state field isn't necessary any more and may be removed. However, dev_pm_qos_add_request() needs to check if the device is being removed from the system before allocating a new PM QoS constraints object for it, so make it use the power.power_state field of struct device for this purpose. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-08-25PM QoS: Implement per-device PM QoS constraintsJean Pihet1-0/+3
Implement the per-device PM QoS constraints by creating a device PM QoS API, which calls the PM QoS constraints management core code. The per-device latency constraints data strctures are stored in the device dev_pm_info struct. The device PM code calls the init and destroy of the per-device constraints data struct in order to support the dynamic insertion and removal of the devices in the system. To minimize the data usage by the per-device constraints, the data struct is only allocated at the first call to dev_pm_qos_add_request. The data is later free'd when the device is removed from the system. A global mutex protects the constraints users from the data being allocated and free'd. Signed-off-by: Jean Pihet <j-pihet@ti.com> Reviewed-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-07-06PM: Limit race conditions between runtime PM and system sleep (v2)Rafael J. Wysocki1-12/+23
One of the roles of the PM core is to prevent different PM callbacks executed for the same device object from racing with each other. Unfortunately, after commit e8665002477f0278f84f898145b1f141ba26ee26 (PM: Allow pm_runtime_suspend() to succeed during system suspend) runtime PM callbacks may be executed concurrently with system suspend/resume callbacks for the same device. The main reason for commit e8665002477f0278f84f898145b1f141ba26ee26 was that some subsystems and device drivers wanted to use runtime PM helpers, pm_runtime_suspend() and pm_runtime_put_sync() in particular, for carrying out the suspend of devices in their .suspend() callbacks. However, as it's been determined recently, there are multiple reasons not to do so, inlcuding: * The caller really doesn't control the runtime PM usage counters, because user space can access them through sysfs and effectively block runtime PM. That means using pm_runtime_suspend() or pm_runtime_get_sync() to suspend devices during system suspend may or may not work. * If a driver calls pm_runtime_suspend() from its .suspend() callback, it causes the subsystem's .runtime_suspend() callback to be executed, which leads to the call sequence: subsys->suspend(dev) driver->suspend(dev) pm_runtime_suspend(dev) subsys->runtime_suspend(dev) recursive from the subsystem's point of view. For some subsystems that may actually work (e.g. the platform bus type), but for some it will fail in a rather spectacular fashion (e.g. PCI). In each case it means a layering violation. * Both the subsystem and the driver can provide .suspend_noirq() callbacks for system suspend that can do whatever the .runtime_suspend() callbacks do just fine, so it really isn't necessary to call pm_runtime_suspend() during system suspend. * The runtime PM's handling of wakeup devices is usually different from the system suspend's one, so .runtime_suspend() may simply be inappropriate for system suspend. * System suspend is supposed to work even if CONFIG_PM_RUNTIME is unset. * The runtime PM workqueue is frozen before system suspend, so if whatever the driver is going to do during system suspend depends on it, that simply won't work. Still, there is a good reason to allow pm_runtime_resume() to succeed during system suspend and resume (for instance, some subsystems and device drivers may legitimately use it to ensure that their devices are in full-power states before suspending them). Moreover, there is no reason to prevent runtime PM callbacks from being executed in parallel with the system suspend/resume .prepare() and .complete() callbacks and the code removed by commit e8665002477f0278f84f898145b1f141ba26ee26 went too far in this respect. On the other hand, runtime PM callbacks, including .runtime_resume(), must not be executed during system suspend's "late" stage of suspending devices and during system resume's "early" device resume stage. Taking all of the above into consideration, make the PM core acquire a runtime PM reference to every device and resume it if there's a runtime PM resume request pending right before executing the subsystem-level .suspend() callback for it. Make the PM core drop references to all devices right after executing the subsystem-level .resume() callbacks for them. Additionally, make the PM core disable the runtime PM framework for all devices during system suspend, after executing the subsystem-level .suspend() callbacks for them, and enable the runtime PM framework for all devices during system resume, right before executing the subsystem-level .resume() callbacks for them. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Kevin Hilman <khilman@ti.com>
2011-07-02PM / Domains: Rename struct dev_power_domain to struct dev_pm_domainRafael J. Wysocki1-15/+15
The naming convention used by commit 7538e3db6e015e890825fbd9f86599b (PM: Add support for device power domains), which introduced the struct dev_power_domain type for representing device power domains, evidently confuses some developers who tend to think that objects of this type must correspond to "power domains" as defined by hardware, which is not the case. Namely, at the kernel level, a struct dev_power_domain object can represent arbitrary set of devices that are mutually dependent power management-wise and need not belong to one hardware power domain. To avoid that confusion, rename struct dev_power_domain to struct dev_pm_domain and rename the related pointers in struct device and struct pm_clk_notifier_block from pwr_domain to pm_domain. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Kevin Hilman <khilman@ti.com>
2011-06-21PM: Fix async resume following suspend failureAlan Stern1-2/+12
The PM core doesn't handle suspend failures correctly when it comes to asynchronously suspended devices. These devices are moved onto the dpm_suspended_list as soon as the corresponding async thread is started up, and they remain on the list even if they fail to suspend or the sleep transition is cancelled before they get suspended. As a result, when the PM core unwinds the transition, it tries to resume the devices even though they were never suspended. This patch (as1474) fixes the problem by adding a new "is_suspended" flag to dev_pm_info. Devices are resumed only if the flag is set. [rjw: * Moved the dev->power.is_suspended check into device_resume(), because we need to complete dev->power.completion and clear dev->power.is_prepared too for devices whose dev->power.is_suspended flags are unset. * Fixed __device_suspend() to avoid setting dev->power.is_suspended if async_error is different from zero.] Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Cc: stable@kernel.org
2011-06-21PM: Rename dev_pm_info.in_suspend to is_preparedAlan Stern1-5/+9
This patch (as1473) renames the "in_suspend" field in struct dev_pm_info to "is_prepared", in preparation for an upcoming change. The new name is more descriptive of what the field really means. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Cc: stable@kernel.org
2011-05-17PM: 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>
2011-04-29PM: Make power domain callbacks take precedence over subsystem onesRafael J. Wysocki1-33/+31
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. Wysocki1-0/+1
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>
2011-04-11PM / Hibernate: Introduce CONFIG_HIBERNATE_CALLBACKSRafael J. Wysocki1-4/+4
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>
2011-03-15PM: Make system-wide PM and runtime PM treat subsystems consistentlyRafael J. Wysocki1-86/+64
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>