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2012-04-29PM / Freezer / Docs: Update documentation about freezing of tasksMarcos Paulo de Souza1-18/+19
The file Documentation/power/freezing-of-tasks.txt was still referencing the TIF_FREEZE flag, that was removed by the commit d88e4cb67197d007fb778d62fe17360e970d5bfa(freezer: remove now unused TIF_FREEZE). This patch removes all the references of TIF_FREEZE that were left behind. Signed-off-by: Marcos Paulo de Souza <marcos.souza.org@gmail.com> Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-02-09PM / Freezer / Docs: Document the beauty of freeze/thaw semanticsSrivatsa S. Bhat1-0/+21
The way the different freeze/thaw functions encapsulate each other are quite lovely from a design point of view. And as a side-effect, the way in which they are invoked (cleaning up on failure for example) differs significantly from how usual functions are dealt with. This is because of the underlying semantics that govern the freezing and thawing of various tasks. This subtle aspect that differentiates these functions from the rest, is worth documenting. Many thanks to Tejun Heo for providing enlightenment on this topic. Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-01-29PM / Sleep: Introduce "late suspend" and "early resume" of devicesRafael J. Wysocki1-32/+61
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>
2012-01-19PM / Documentation: Fix minor issue in freezing_of_tasks.txtViresh Kumar1-4/+4
In a paragraph, "kernel thread" is mistakenly written as "kernel". Fix this by adding thread after word "kernel". Changes are shown in multiple lines, as they are realigned to 80 col width. Signed-off-by: Viresh Kumar <viresh.kumar@st.com> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-01-19PM / Documentation: Fix spelling mistake in basic-pm-debugging.txtViresh Kumar1-1/+1
Signed-off-by: Viresh Kumar <viresh.kumar@st.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-01-11Merge git://git.infradead.org/battery-2.6Linus Torvalds1-0/+163
* git://git.infradead.org/battery-2.6: (68 commits) power_supply: Mark da9052 driver as broken power_supply: Drop usage of nowarn variant of sysfs_create_link() s3c_adc_battery: Average over more than one adc sample power_supply: Add DA9052 battery driver isp1704_charger: Fix missing check jz4740-battery: Fix signedness bug power_supply: Assume mains power by default sbs-battery: Fix devicetree match table ARM: rx51: Add bq27200 i2c board info sbs-battery: Change power supply name devicetree-bindings: Propagate bq20z75->sbs rename to dt bindings devicetree-bindings: Add vendor entry for Smart Battery Systems sbs-battery: Rename internals to new name bq20z75: Rename to sbs-battery wm97xx_battery: Use DEFINE_MUTEX() for work_lock max8997_charger: Remove duplicate module.h lp8727_charger: Some minor fixes for the header lp8727_charger: Add header file power_supply: Convert drivers/power/* to use module_platform_driver() power_supply: Add "unknown" in power supply type ...
2012-01-10Merge branch 'for-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator: (40 commits) regulator: set constraints.apply_uV to 0 in of_get_fixed_voltage_config regulator: max8925: fix enabled/disabled judgement mistake regulator: add regulator_bulk_force_disable function regulator: pass regulator_register of_node in fixed voltage driver regulator: add regulator_force_disable() definition for !CONFIG_REGULATOR regulator: Enable supply regulator if child rail is enabled. regulator: mc13892: Convert to devm_kzalloc() regulator: mc13783: Convert to devm_kzalloc() regulator: Fix checking return value of create_regulator regulator: Fix the error handling if create_regulator fails regulator: Export regulator_is_supported_voltage() regulator: mc13892: add device tree probe support regulator: mc13892: remove the unnecessary prefix from regulator name regulator: Convert wm831x regulator drivers to devm_kzalloc() regulator: da9052: Staticize non-exported symbols regulator: Replace kzalloc with devm_kzalloc and if-else with a switch-case for da9052-regulator regulator: Update da9052-regulator for DT changes regulator: DA9052/53 Regulator support regulator: pass device_node to of_get_regulator_init_data() regulator: If a single voltage is set with device tree then set apply_uV ...
2012-01-04Merge branch 'power-supply-scope' of ↵Anton Vorontsov9-29/+435
git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen
2012-01-04power_supply: Charger-Manager: Add properties for power-supply-classDonggeun Kim1-0/+14
Charger Manager provides power-supply-class aggregating information from multiple chargers and a fuel-gauge. Signed-off-by: Donggeun Kim <dg77.kim@samsung.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
2012-01-04power_supply: Add initial Charger-Manager driverDonggeun Kim1-0/+149
Because battery health monitoring should be done even when suspended, it needs to wake up and suspend periodically. Thus, userspace battery monitoring may incur too much overhead; every device and task is woken up periodically. Charger Manager uses suspend-again to provide in-suspend monitoring. This patch allows to monitor battery health in-suspend state. Signed-off-by: Donggeun Kim <dg77.kim@samsung.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
2011-12-21PM: Run the driver callback directly if the subsystem one is not thereRafael J. Wysocki2-78/+89
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>
2011-12-21Merge branch 'master' into pm-sleepRafael J. Wysocki2-58/+93
* master: (848 commits) SELinux: Fix RCU deref check warning in sel_netport_insert() binary_sysctl(): fix memory leak mm/vmalloc.c: remove static declaration of va from __get_vm_area_node ipmi_watchdog: restore settings when BMC reset oom: fix integer overflow of points in oom_badness memcg: keep root group unchanged if creation fails nilfs2: potential integer overflow in nilfs_ioctl_clean_segments() nilfs2: unbreak compat ioctl cpusets: stall when updating mems_allowed for mempolicy or disjoint nodemask evm: prevent racing during tfm allocation evm: key must be set once during initialization mmc: vub300: fix type of firmware_rom_wait_states module parameter Revert "mmc: enable runtime PM by default" mmc: sdhci: remove "state" argument from sdhci_suspend_host x86, dumpstack: Fix code bytes breakage due to missing KERN_CONT IB/qib: Correct sense on freectxts increment and decrement RDMA/cma: Verify private data length cgroups: fix a css_set not found bug in cgroup_attach_proc oprofile: Fix uninitialized memory access when writing to writing to oprofilefs Revert "xen/pv-on-hvm kexec: add xs_reset_watches to shutdown watches from old kernel" ... Conflicts: kernel/cgroup_freezer.c
2011-12-08PM / Sleep: Recommend [un]lock_system_sleep() over using pm_mutex directlySrivatsa S. Bhat1-0/+25
Update the documentation to explain the perils of directly using mutex_[un]lock(&pm_mutex) and recommend the usage of the safe APIs [un]lock_system_sleep() instead. Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-12-05regulator: Fix regulator_register() API signature in DocumentationRajendra Nayak1-1/+1
The commit 2c043bcbf287 ("regulator: pass additional of_node to regulator_register()") added an additional parameter to the regulator_register() API. Update the Documentation accordingly to reflect the change in the function signature. Reported-by: Thomas Abraham <thomas.abraham@linaro.org> Signed-off-by: Rajendra Nayak <rnayak@ti.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-28PM / Sleep: Update documentation related to system wakeupRafael J. Wysocki1-22/+38
The system wakeup section of Documentation/power/devices.txt is outdated, so make it agree with the current code. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-11-28PM / Runtime: Make documentation follow the new behavior of irq_safeRafael J. Wysocki1-5/+6
The runtime PM core code behavior related to the power.irq_safe device flag has changed recently and the documentation should be modified to reflect it. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-11-28PM / Sleep: Correct inaccurate information in devices.txtRafael J. Wysocki1-4/+3
The documentation file Documentation/power/devices.txt contains some information that isn't correct any more due to code modifications made after that file had been created (or updated last time). Fix this. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-11-28PM / Domains: Document how PM domains are used by the PM coreRafael J. Wysocki2-26/+45
The current power management documentation in Documentation/power/ either doesn't cover PM domains at all, or gives inaccurate information about them, so update the relevant files in there to follow the code. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-11-21freezer: unexport refrigerator() and update try_to_freeze() slightlyTejun Heo1-6/+6
There is no reason to export two functions for entering the refrigerator. Calling refrigerator() instead of try_to_freeze() doesn't save anything noticeable or removes any race condition. * Rename refrigerator() to __refrigerator() and make it return bool indicating whether it scheduled out for freezing. * Update try_to_freeze() to return bool and relay the return value of __refrigerator() if freezing(). * Convert all refrigerator() users to try_to_freeze(). * Update documentation accordingly. * While at it, add might_sleep() to try_to_freeze(). Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Samuel Ortiz <samuel@sortiz.org> Cc: Chris Mason <chris.mason@oracle.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Jan Kara <jack@suse.cz> Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp> Cc: Christoph Hellwig <hch@infradead.org>
2011-11-21freezer: don't unnecessarily set PF_NOFREEZE explicitlyTejun Heo1-1/+1
Some drivers set PF_NOFREEZE in their kthread functions which is completely unnecessary and racy - some part of freezer code doesn't consider cases where PF_NOFREEZE is set asynchronous to freezer operations. In general, there's no reason to allow setting PF_NOFREEZE explicitly. Remove them and change the documentation to note that setting PF_NOFREEZE directly isn't allowed. -v2: Dropped change to twl4030-irq.c as it no longer uses PF_NOFREEZE. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: "Gustavo F. Padovan" <padovan@profusion.mobi> Acked-by: Samuel Ortiz <sameo@linux.intel.com> Cc: Marcel Holtmann <marcel@holtmann.org> Cc: wwang <wei_wang@realsil.com.cn>
2011-11-04PM / Runtime: Automatically retry failed autosuspendsAlan Stern1-0/+10
Originally, the runtime PM core would send an idle notification whenever a suspend attempt failed. The idle callback routine could then schedule a delayed suspend for some time later. However this behavior was changed by commit f71648d73c1650b8b4aceb3856bebbde6daa3b86 (PM / Runtime: Remove idle notification after failing suspend). No notifications were sent, and there was no clear mechanism to retry failed suspends. This caused problems for the usbhid driver, because it fails autosuspend attempts as long as a key is being held down. Therefore this patch (as1492) adds a mechanism for retrying failed autosuspends. If the callback routine updates the last_busy field so that the next autosuspend expiration time is in the future, the autosuspend will automatically be rescheduled. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Tested-by: Henrik Rydberg <rydberg@euromail.se> Cc: <stable@kernel.org> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-11-04PM / Sleep: Update freezer documentationSrivatsa S. Bhat1-4/+4
This patch: * Substitutes some obsolete references to kernel/power/process.c by kernel/freezer.c. * Mentions kernel/freezer.c as being part of the "freezer" code along with the rest of the files. * Fixes a trivial typo. Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-11-01Merge branch 'for-linus' of git://opensource.wolfsonmicro.com/regulatorLinus Torvalds1-6/+13
* 'for-linus' of git://opensource.wolfsonmicro.com/regulator: (22 commits) regulator: Constify constraints name regulator: Fix possible nullpointer dereference in regulator_enable() regulator: gpio-regulator add dependency on GENERIC_GPIO regulator: Add module.h include to gpio-regulator regulator: Add driver for gpio-controlled regulators regulator: remove duplicate REG_CTRL2 defines in tps65023 regulator: Clarify documentation for regulator-regulator supplies regulator: Fix some bitrot in the machine driver documentation regulator: tps65023: Added support for the similiar TPS65020 chip regulator: tps65023: Setting correct core regulator for tps65021 regulator: tps65023: Set missing bit for update core-voltage regulator: tps65023: Fixes i2c configuration issues regulator: Add debugfs file showing the supply map table regulator: tps6586x: add SMx slew rate setting regulator: tps65023: Fixes i2c configuration issues regulator: tps6507x: Remove num_voltages array regulator: max8952: removed unused mutex. regulator: fix regulator/consumer.h kernel-doc warning regulator: Ensure enough enable time for max8649 regulator: 88pm8607: Fix off-by-one value range checking in the case of no id is matched ...
2011-10-25Merge branch 'pm-for-linus' of ↵Linus Torvalds6-17/+405
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm * 'pm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (63 commits) PM / Clocks: Remove redundant NULL checks before kfree() PM / Documentation: Update docs about suspend and CPU hotplug ACPI / PM: Add Sony VGN-FW21E to nonvs blacklist. ARM: mach-shmobile: sh7372 A4R support (v4) ARM: mach-shmobile: sh7372 A3SP support (v4) PM / Sleep: Mark devices involved in wakeup signaling during suspend PM / Hibernate: Improve performance of LZO/plain hibernation, checksum image PM / Hibernate: Do not initialize static and extern variables to 0 PM / Freezer: Make fake_signal_wake_up() wake TASK_KILLABLE tasks too PM / Hibernate: Add resumedelay kernel param in addition to resumewait MAINTAINERS: Update linux-pm list address PM / ACPI: Blacklist Vaio VGN-FW520F machine known to require acpi_sleep=nonvs PM / ACPI: Blacklist Sony Vaio known to require acpi_sleep=nonvs PM / Hibernate: Add resumewait param to support MMC-like devices as resume file PM / Hibernate: Fix typo in a kerneldoc comment PM / Hibernate: Freeze kernel threads after preallocating memory PM: Update the policy on default wakeup settings PM / VT: Cleanup #if defined uglyness and fix compile error PM / Suspend: Off by one in pm_suspend() PM / Hibernate: Include storage keys in hibernation image on s390 ...
2011-10-22PM / Documentation: Update docs about suspend and CPU hotplugSrivatsa S. Bhat2-0/+277
Update the documentation about the interaction between the suspend (S3) call path and the CPU hotplug infrastructure. This patch focusses only on the activities of the freezer, cpu hotplug and the notifications involved. It outlines how regular CPU hotplug differs from the way it is invoked during suspend and also tries to explain the locking involved. In addition to that, it discusses the issue of microcode update during CPU hotplug operations. Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-10-16PM / Hibernate: Freeze kernel threads after preallocating memoryRafael J. Wysocki1-4/+0
There is a problem with the current ordering of hibernate code which leads to deadlocks in some filesystems' memory shrinkers. Namely, some filesystems use freezable kernel threads that are inactive when the hibernate memory preallocation is carried out. Those same filesystems use memory shrinkers that may be triggered by the hibernate memory preallocation. If those memory shrinkers wait for the frozen kernel threads, the hibernate process deadlocks (this happens with XFS, for one example). Apparently, it is not technically viable to redesign the filesystems in question to avoid the situation described above, so the only possible solution of this issue is to defer the freezing of kernel threads until the hibernate memory preallocation is done, which is implemented by this change. Unfortunately, this requires the memory preallocation to be done before the "prepare" stage of device freeze, so after this change the only way drivers can allocate additional memory for their freeze routines in a clean way is to use PM notifiers. Reported-by: Christoph <cr2005@u-club.de> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-10-16PM: Update the policy on default wakeup settingsAlan Stern1-1/+3
This patch (as1485) documents a change to the kernel's default wakeup policy. Devices that forward wakeup requests between buses should be enabled for wakeup by default. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-10-16PM / Suspend: Add statistics debugfs file for suspend to RAMShuoX Liu1-0/+24
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>
2011-10-16Merge branch 'pm-runtime' into pm-for-linusRafael J. Wysocki1-7/+12
* pm-runtime: PM / Runtime: Handle .runtime_suspend() failure correctly PM / Runtime: Fix kerneldoc comment for rpm_suspend() PM / Runtime: Update document about callbacks
2011-10-10PM / Runtime: Update document about callbacksMing Lei1-7/+12
Support for device power domains has been introduced in commit 9659cc0678b954f187290c6e8b247a673c5d37e1 (PM: Make system-wide PM and runtime PM treat subsystems consistently), also power domain callbacks will take precedence over subsystem ones from commit 4d27e9dcff00a6425d779b065ec8892e4f391661(PM: Make power domain callbacks take precedence over subsystem ones). So update part of "Device Runtime PM Callbacks" in Documentation/power/runtime_pm.txt. Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-10-07Merge branch 'pm-qos' into pm-for-linusRafael J. Wysocki1-5/+87
* pm-qos: PM / QoS: Update Documentation for the pm_qos and dev_pm_qos frameworks PM / QoS: Add function dev_pm_qos_read_value() (v3) PM QoS: Add global notification mechanism for device constraints PM QoS: Implement per-device PM QoS constraints PM QoS: Generalize and export constraints management code PM QoS: Reorganize data structs PM QoS: Code reorganization PM QoS: Minor clean-ups PM QoS: Move and rename the implementation files
2011-10-07Merge branch 'pm-runtime' into pm-for-linusRafael J. Wysocki1-0/+2
* pm-runtime: PM / Tracing: build rpm-traces.c only if CONFIG_PM_RUNTIME is set PM / Runtime: Replace dev_dbg() with trace_rpm_*() PM / Runtime: Introduce trace points for tracing rpm_* functions PM / Runtime: Don't run callbacks under lock for power.irq_safe set USB: Add wakeup info to debugging messages PM / Runtime: pm_runtime_idle() can be called in atomic context PM / Runtime: Add macro to test for runtime PM events PM / Runtime: Add might_sleep() to runtime PM functions
2011-10-07regulator: Clarify documentation for regulator-regulator suppliesMark Brown1-2/+9
The mechanism used for connecting regulators together when one regulator supplies another wasn't clear as the names being used weren't really tied together well. Reported-by: Philip Rakity <prakity@marvell.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-10-07regulator: Fix some bitrot in the machine driver documentationMark Brown1-4/+4
The documentation for the machine driver was rather badly bitrotted, using pointers to struct device rather than dev_name() to hook up the consumers. Update to use dev_name(). Reported-by: Philip Rakity <prakity@marvell.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-10-04PM / QoS: Update Documentation for the pm_qos and dev_pm_qos frameworksJean Pihet1-5/+87
Update the documentation for the recently updated pm_qos API, kernel and user space. Add documentation for the per-device PM QoS (dev_pm_qos) framework API. Signed-off-by: Jean Pihet <j-pihet@ti.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-09-27doc: fix broken referencesPaul Bolle2-2/+3
There are numerous broken references to Documentation files (in other Documentation files, in comments, etc.). These broken references are caused by typo's in the references, and by renames or removals of the Documentation files. Some broken references are simply odd. Fix these broken references, sometimes by dropping the irrelevant text they were part of. Signed-off-by: Paul Bolle <pebolle@tiscali.nl> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-09-21PM / Runtime: pm_runtime_idle() can be called in atomic contextMing Lei1-0/+1
Add to pm_runtime_idle the list of functions that can be called in atomic context if pm_runtime_irq_safe() has been called for the device. Signed-off-by: Ming Lei <tom.leiming@gmail.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-08-25PM / Runtime: Correct documentation of pm_runtime_irq_safe()Rafael J. Wysocki1-2/+1
The description of pm_runtime_irq_safe() has to be updated to follow the code after commit 02b2677 (PM / Runtime: Allow _put_sync() from interrupts-disabled context). Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Kevin Hilman <khilman@ti.com>
2011-08-14PM / Runtime: Add might_sleep() to runtime PM functionsColin Cross1-0/+1
Some of the entry points to pm runtime are not safe to call in atomic context unless pm_runtime_irq_safe() has been called. Inspecting the code, it is not immediately obvious that the functions sleep at all, as they run inside a spin_lock_irqsave, but under some conditions they can drop the lock and turn on irqs. If a driver incorrectly calls the pm_runtime apis, it can cause sleeping and irq processing when it expects to stay in atomic context. Add might_sleep_if to the majority of the __pm_runtime_* entry points to enforce correct usage. Add pm_runtime_put_sync_autosuspend to the list of functions that can be called in atomic context. Signed-off-by: Colin Cross <ccross@android.com> Reviewed-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-08-05PM / Runtime: Allow _put_sync() from interrupts-disabled contextKevin Hilman1-5/+5
Currently the use of pm_runtime_put_sync() is not safe from interrupts-disabled context because rpm_idle() will release the spinlock and enable interrupts for the idle callbacks. This enables interrupts during a time where interrupts were expected to be disabled, and can have strange side effects on drivers that expected interrupts to be disabled. This is not a bug since the documentation clearly states that only _put_sync_suspend() is safe in IRQ-safe mode. However, pm_runtime_put_sync() could be made safe when in IRQ-safe mode by releasing the spinlock but not re-enabling interrupts, which is what this patch aims to do. Problem was found when using some buggy drivers that set pm_runtime_irq_safe() and used _put_sync() in interrupts-disabled context. Reported-by: Colin Cross <ccross@google.com> Tested-by: Nishanth Menon <nm@ti.com> Signed-off-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-07-15Merge branch 'pm-runtime' into for-linusRafael J. Wysocki2-78/+125
* pm-runtime: OMAP: PM: disable idle on suspend for GPIO and UART OMAP: PM: omap_device: add API to disable idle on suspend OMAP: PM: omap_device: add system PM methods for PM domain handling OMAP: PM: omap_device: conditionally use PM domain runtime helpers PM / Runtime: Add new helper function: pm_runtime_status_suspended() PM / Runtime: Consistent utilization of deferred_resume PM / Runtime: Prevent runtime_resume from racing with probe PM / Runtime: Replace "run-time" with "runtime" in documentation PM / Runtime: Improve documentation of enable, disable and barrier PM: Limit race conditions between runtime PM and system sleep (v2) PCI / PM: Detect early wakeup in pci_pm_prepare() PM / Runtime: Return special error code if runtime PM is disabled PM / Runtime: Update documentation of interactions with system sleep
2011-07-15Merge branch 'pm-domains' into for-linusRafael J. Wysocki2-6/+34
* pm-domains: (33 commits) ARM / shmobile: Return -EBUSY from A4LC power off if A3RV is active PM / Domains: Take .power_off() error code into account ARM / shmobile: Use genpd_queue_power_off_work() ARM / shmobile: Use pm_genpd_poweroff_unused() PM / Domains: Introduce function to power off all unused PM domains PM / Domains: Queue up power off work only if it is not pending PM / Domains: Improve handling of wakeup devices during system suspend PM / Domains: Do not restore all devices on power off error PM / Domains: Allow callbacks to execute all runtime PM helpers PM / Domains: Do not execute device callbacks under locks PM / Domains: Make failing pm_genpd_prepare() clean up properly PM / Domains: Set device state to "active" during system resume ARM: mach-shmobile: sh7372 A3RV requires A4LC PM / Domains: Export pm_genpd_poweron() in header ARM: mach-shmobile: sh7372 late pm domain off ARM: mach-shmobile: Runtime PM late init callback ARM: mach-shmobile: sh7372 D4 support ARM: mach-shmobile: sh7372 A4MP support ARM: mach-shmobile: sh7372: make sure that fsi is peripheral of spu2 ARM: mach-shmobile: sh7372 A3SG support ...
2011-07-15PM / OPP: Introduce function to free cpufreq tableNishanth Menon1-0/+2
cpufreq table allocated by opp_init_cpufreq_table is better freed by OPP layer itself. This allows future modifications to the table handling to be transparent to the users. Signed-off-by: Nishanth Menon <nm@ti.com> Acked-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-07-12PM / Runtime: Add new helper function: pm_runtime_status_suspended()Kevin Hilman1-0/+3
This boolean function simply returns whether or not the runtime status of the device is 'suspended'. Unlike pm_runtime_suspended(), this function returns the runtime status whether or not runtime PM for the device has been disabled or not. Also add entry to Documentation/power/runtime.txt Signed-off-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-07-06PM / Runtime: Replace "run-time" with "runtime" in documentationRafael J. Wysocki1-65/+65
The runtime PM documentation and kerneldoc comments sometimes spell "runtime" with a dash (i.e. "run-time"). Replace all of those instances with "runtime" to make the naming consistent. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-07-06PM / Runtime: Improve documentation of enable, disable and barrierRafael J. Wysocki1-4/+14
The runtime PM documentation in Documentation/power/runtime_pm.txt doesn't say that pm_runtime_enable() and pm_runtime_disable() work by operating on power.disable_depth, which is wrong, because the possibility of nesting disables doesn't follow from the description of these functions. Also, there is no description of pm_runtime_barrier() at all in the document, which is confusing. Improve the documentation by fixing those issues. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-07-06PM: Limit race conditions between runtime PM and system sleep (v2)Rafael J. Wysocki1-0/+21
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 / Runtime: Return special error code if runtime PM is disabledRafael J. Wysocki1-2/+4
Some callers of pm_runtime_get_sync() and other runtime PM helper functions, scsi_autopm_get_host() and scsi_autopm_get_device() in particular, need to distinguish error codes returned when runtime PM is disabled (i.e. power.disable_depth is nonzero for the given device) from error codes returned in other situations. For this reason, make the runtime PM helper functions return -EACCES when power.disable_depth is nonzero and ensure that this error code won't be returned by them in any other circumstances. Modify scsi_autopm_get_host() and scsi_autopm_get_device() to check the error code returned by pm_runtime_get_sync() and ignore -EACCES. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-07-02PM / Runtime: Update documentation of interactions with system sleepRafael J. Wysocki2-11/+22
The documents describing the interactions between runtime PM and system sleep generally refer to the model in which the system sleep state is entered through a global firmware or hardware operation. As a result, some recommendations given in there are not entirely suitable for systems in which this is not the case. Update the documentation to take the existence of those systems into account. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Reviewed-by: Kevin Hilman <khilman@ti.com>
2011-07-02PM: Introduce generic "noirq" callback routines for subsystems (v2)Rafael J. Wysocki1-2/+30
Introduce generic "noirq" power management callback routines for subsystems in addition to the "regular" generic PM callback routines. The new routines will be used, among other things, for implementing system-wide PM transitions support for generic PM domains. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>