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path: root/drivers/base/power/main.c
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2010-12-24PM: Use pm_wakeup_pending() in __device_suspend()Rafael J. Wysocki
Before starting to suspend a device in __device_suspend() check if there's a request to abort the power transition and return -EBUSY in that case. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-12-24PM / Wakeup: Replace pm_check_wakeup_events() with pm_wakeup_pending()Rafael J. Wysocki
To avoid confusion with the meaning and return value of pm_check_wakeup_events() replace it with pm_wakeup_pending() that will work the other way around (ie. return true when system-wide power transition should be aborted). Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-12-24PM: Prevent dpm_prepare() from returning errors unnecessarilyRafael J. Wysocki
Currently dpm_prepare() returns error code if it finds that a device being suspended has a pending runtime resume request. However, it should not do that if the checking for wakeup events is not enabled. On the other hand, if the checking for wakeup events is enabled, it can return error when a wakeup event is detected, regardless of its source. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-12-22Merge branch 'master' into for-nextJiri Kosina
Conflicts: MAINTAINERS arch/arm/mach-omap2/pm24xx.c drivers/scsi/bfa/bfa_fcpim.c Needed to update to apply fixes for which the old branch was too outdated.
2010-11-11PM: Allow devices to be removed during late suspend and early resumeRafael J. Wysocki
Holding dpm_list_mtx across late suspend and early resume of devices is problematic for the PCMCIA subsystem and doesn't allow device objects to be removed by late suspend and early resume driver callbacks. This appears to be overly restrictive, as drivers are generally allowed to remove device objects in other phases of suspend and resume. Therefore rework dpm_{suspend|resume}_noirq() so that they don't have to hold dpm_list_mtx all the time. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-11-01tree-wide: fix comment/printk typosUwe Kleine-König
"gadget", "through", "command", "maintain", "maintain", "controller", "address", "between", "initiali[zs]e", "instead", "function", "select", "already", "equal", "access", "management", "hierarchy", "registration", "interest", "relative", "memory", "offset", "already", Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-10-17PM: Fix potential issue with failing asynchronous suspendRafael J. Wysocki
There is a potential issue with the asynchronous suspend code that a device driver suspending asynchronously may not notice that it should back off. There are two failing scenarions, (1) when the driver is waiting for a driver suspending synchronously to complete and that second driver returns error code, in which case async_error won't be set and the waiting driver will continue suspending and (2) after the driver has called device_pm_wait_for_dev() and the waited for driver returns error code, in which case the caller of device_pm_wait_for_dev() will not know that there was an error and will continue suspending. To fix this issue make __device_suspend() set async_error, so async_suspend() doesn't need to set it any more, and make device_pm_wait_for_dev() return async_error, so that its callers can check whether or not they should continue suspending. No more changes are necessary, since device_pm_wait_for_dev() is not used by any drivers' suspend routines. Reported-by: Colin Cross <ccross@android.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-10-17PM / Wakeup: Introduce wakeup source objects and event statistics (v3)Rafael J. Wysocki
Introduce struct wakeup_source for representing system wakeup sources within the kernel and for collecting statistics related to them. Make the recently introduced helper functions pm_wakeup_event(), pm_stay_awake() and pm_relax() use struct wakeup_source objects internally, so that wakeup statistics associated with wakeup devices can be collected and reported in a consistent way (the definition of pm_relax() is changed, which is harmless, because this function is not called directly by anyone yet). Introduce new wakeup-related sysfs device attributes in /sys/devices/.../power for reporting the device wakeup statistics. Change the global wakeup events counters event_count and events_in_progress into atomic variables, so that it is not necessary to acquire a global spinlock in pm_wakeup_event(), pm_stay_awake() and pm_relax(), which should allow us to avoid lock contention in these functions on SMP systems with many wakeup devices. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-10-17PM: Fix signed/unsigned warning in dpm_show_time()Kevin Cernekee
Seen on MIPS32, gcc 4.4.3, 2.6.36-rc4: drivers/base/power/main.c: In function 'dpm_show_time': drivers/base/power/main.c:415: warning: comparison of distinct pointer types lacks a cast do_div() takes unsigned parameters: uint32_t do_div(uint64_t *n, uint32_t base); Using an unsigned variable for usecs64 should not cause any problems, because calltime >= starttime . Signed-off-by: Kevin Cernekee <cernekee@gmail.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-09-09PM: Prevent waiting forever on asynchronous resume after failing suspendColin Cross
During suspend, the power.completion is expected to be set when a device has not yet started suspending. Set it on init to fix a corner case where a device is resumed when its parent has never suspended. Consider three drivers, A, B, and C. The parent of A is C, and C has async_suspend set. On boot, C->power.completion is initialized to 0. During the first suspend: suspend_devices_and_enter(...) dpm_resume(...) device_suspend(A) device_suspend(B) returns error, aborts suspend dpm_resume_end(...) dpm_resume(...) device_resume(A) dpm_wait(A->parent == C) wait_for_completion(C->power.completion) The wait_for_completion will never complete, because complete_all(C->power.completion) will only be called from device_suspend(C) or device_resume(C), neither of which is called if suspend is aborted before C. After a successful suspend->resume cycle, where B doesn't abort suspend, C->power.completion is left in the completed state by the call to device_resume(C), and the same call path will work if B aborts suspend. Signed-off-by: Colin Cross <ccross@android.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-07-19PM: Make it possible to avoid races between wakeup and system sleepRafael J. Wysocki
One of the arguments during the suspend blockers discussion was that the mainline kernel didn't contain any mechanisms making it possible to avoid races between wakeup and system suspend. Generally, there are two problems in that area. First, if a wakeup event occurs exactly when /sys/power/state is being written to, it may be delivered to user space right before the freezer kicks in, so the user space consumer of the event may not be able to process it before the system is suspended. Second, if a wakeup event occurs after user space has been frozen, it is not generally guaranteed that the ongoing transition of the system into a sleep state will be aborted. To address these issues introduce a new global sysfs attribute, /sys/power/wakeup_count, associated with a running counter of wakeup events and three helper functions, pm_stay_awake(), pm_relax(), and pm_wakeup_event(), that may be used by kernel subsystems to control the behavior of this attribute and to request the PM core to abort system transitions into a sleep state already in progress. The /sys/power/wakeup_count file may be read from or written to by user space. Reads will always succeed (unless interrupted by a signal) and return the current value of the wakeup events counter. Writes, however, will only succeed if the written number is equal to the current value of the wakeup events counter. If a write is successful, it will cause the kernel to save the current value of the wakeup events counter and to abort the subsequent system transition into a sleep state if any wakeup events are reported after the write has returned. [The assumption is that before writing to /sys/power/state user space will first read from /sys/power/wakeup_count. Next, user space consumers of wakeup events will have a chance to acknowledge or veto the upcoming system transition to a sleep state. Finally, if the transition is allowed to proceed, /sys/power/wakeup_count will be written to and if that succeeds, /sys/power/state will be written to as well. Still, if any wakeup events are reported to the PM core by kernel subsystems after that point, the transition will be aborted.] Additionally, put a wakeup events counter into struct dev_pm_info and make these per-device wakeup event counters available via sysfs, so that it's possible to check the activity of various wakeup event sources within the kernel. To illustrate how subsystems can use pm_wakeup_event(), make the low-level PCI runtime PM wakeup-handling code use it. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Acked-by: markgross <markgross@thegnar.org> Reviewed-by: Alan Stern <stern@rowland.harvard.edu>
2010-03-24power: support _noirq actions on device types and classesDominik Brodowski
The new-style dev_pm_ops provide callbacks for both IRQs enabled and disabled. However, the _noirq variants were only called for buses registered with a device, not for classes and types. In order to properly use dev_pm_ops in class pcmcia_socket_class, support _noirq actions also on classes and types. Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-03-07Driver core: create lock/unlock functions for struct deviceGreg Kroah-Hartman
In the future, we are going to be changing the lock type for struct device (once we get the lockdep infrastructure properly worked out) To make that changeover easier, and to possibly burry the lock in a different part of struct device, let's create some functions to lock and unlock a device so that no out-of-core code needs to be changed in the future. This patch creates the device_lock/unlock/trylock() functions, and converts all in-tree users to them. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Jean Delvare <khali@linux-fr.org> Cc: Dave Young <hidave.darkstar@gmail.com> Cc: Ming Lei <tom.leiming@gmail.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Phil Carmody <ext-phil.2.carmody@nokia.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Rafael J. Wysocki <rjw@sisk.pl> Cc: Pavel Machek <pavel@ucw.cz> Cc: Len Brown <len.brown@intel.com> Cc: Magnus Damm <damm@igel.co.jp> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: Randy Dunlap <randy.dunlap@oracle.com> Cc: Stefan Richter <stefanr@s5r6.in-berlin.de> Cc: David Brownell <dbrownell@users.sourceforge.net> Cc: Vegard Nossum <vegard.nossum@gmail.com> Cc: Jesse Barnes <jbarnes@virtuousgeek.org> Cc: Alex Chiang <achiang@hp.com> Cc: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andrew Patterson <andrew.patterson@hp.com> Cc: Yu Zhao <yu.zhao@intel.com> Cc: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Samuel Ortiz <sameo@linux.intel.com> Cc: Wolfram Sang <w.sang@pengutronix.de> Cc: CHENG Renquan <rqcheng@smu.edu.sg> Cc: Oliver Neukum <oliver@neukum.org> Cc: Frans Pop <elendil@planet.nl> Cc: David Vrabel <david.vrabel@csr.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-02-26PM: Allow device drivers to use dpm_wait()Rafael J. Wysocki
There are some dependencies between devices (in particular, between EHCI USB controllers and their OHCI/UHCI siblings) which are not reflected by the structure of the device tree. With synchronous suspend and resume these dependencies are taken into accout automatically, because the devices in question are always registered in the right order, but to meet these constraints with asynchronous suspend and resume the drivers of these devices will need to use dpm_wait() in their suspend/resume routines, so introduce a helper function allowing them to do that. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-02-26PM: Start asynchronous resume threads upfrontRafael J. Wysocki
It has been shown by testing that total device resume time can be reduced significantly (by as much as 50% or more) if the async threads executing some devices' resume routines are all started before the main resume thread starts to handle the "synchronous" devices. This is a consequence of the fact that the slowest devices tend to be located at the end of dpm_list, so their resume routines are started very late. Consequently, they have to wait for all the preceding "synchronous" devices before their resume routines can be started by the main resume thread, even if they are "asynchronous". By starting their async threads upfront we effectively move those devices towards the beginning of dpm_list, without breaking their ordering with respect to their parents and children. As a result, their resume routines are started much earlier and we are able to save much more device resume time this way. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-02-26PM: Add a switch for disabling/enabling asynchronous suspend/resumeRafael J. Wysocki
Add sysfs attribute /sys/power/pm_async allowing the user space to disable/enable asynchronous suspend/resume of devices. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-02-26PM: Asynchronous suspend and resume of devicesRafael J. Wysocki
Theoretically, the total time of system sleep transitions (suspend to RAM, hibernation) can be reduced by running suspend and resume callbacks of device drivers in parallel with each other. However, there are dependencies between devices such that we're not allowed to suspend the parent of a device before suspending the device itself. Analogously, we're not allowed to resume a device before resuming its parent. The most straightforward way to take these dependencies into accout is to start the async threads used for suspending and resuming devices at the core level, so that async_schedule() is called for each suspend and resume callback supposed to be executed asynchronously. For this purpose, introduce a new device flag, power.async_suspend, used to mark the devices whose suspend and resume callbacks are to be executed asynchronously (ie. in parallel with the main suspend/resume thread and possibly in parallel with each other) and helper function device_enable_async_suspend() allowing one to set power.async_suspend for given device (power.async_suspend is unset by default for all devices). For each device with the power.async_suspend flag set the PM core will use async_schedule() to execute its suspend and resume callbacks. The async threads started for different devices as a result of calling async_schedule() are synchronized with each other and with the main suspend/resume thread with the help of completions, in the following way: (1) There is a completion, power.completion, for each device object. (2) Each device's completion is reset before calling async_schedule() for the device or, in the case of devices with the power.async_suspend flags unset, before executing the device's suspend and resume callbacks. (3) During suspend, right before running the bus type, device type and device class suspend callbacks for the device, the PM core waits for the completions of all the device's children to be completed. (4) During resume, right before running the bus type, device type and device class resume callbacks for the device, the PM core waits for the completion of the device's parent to be completed. (5) The PM core completes power.completion for each device right after the bus type, device type and device class suspend (or resume) callbacks executed for the device have returned. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-02-26PM: Add parent information to timing messagesRafael J. Wysocki
Add parent information to the messages printed by the suspend/resume core when initcall_debug is set. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-01-11power: fix kernel-doc notationRandy Dunlap
Warning(drivers/base/power/main.c:453): No description found for parameter 'dev' Warning(drivers/base/power/main.c:453): No description found for parameter 'cb' Warning(drivers/base/power/main.c:719): No description found for parameter 'dev' Warning(drivers/base/power/main.c:719): No description found for parameter 'state' Warning(drivers/base/power/main.c:719): No description found for parameter 'cb' Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-21PM: Use pm_runtime_put_sync in system resumeAlan Stern
This patch (as1317) fixes a bug in the PM core. When a device is resumed following a system sleep, the core decrements the device's runtime PM usage counter but doesn't issue an idle notification if the counter reaches 0. This could prevent an otherwise unused device from being runtime-suspended again after the system sleep. The fix is to call pm_runtime_put_sync() instead of pm_runtime_put_noidle(). Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2009-12-18PM: Measure device suspend and resume timesRafael J. Wysocki
Measure and print the time of suspending and resuming all devices. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2009-12-18PM: Make the initcall_debug style timing for suspend/resume completeRafael J. Wysocki
Commit f2511774863487e61b56a97da07ebf8dd61d7836 (PM: Add initcall_debug style timing for suspend/resume) introduced basic timing instrumentation, needed for a scritps/bootgraph.pl equivalent or humans, but it missed the fact that bus types and device classes which haven't been switched to using struct dev_pm_ops objects yet need special handling. As a result, the suspend/resume timing information is only available for devices whose bus types or device classes use struct dev_pm_ops objects, so the majority of devices is not covered. Fix this by adding basic suspend/resume timing instrumentation for devices whose bus types and device classes still don't use struct dev_pm_ops objects for power management. To reduce code duplication move the timing code to helper functions. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2009-12-15PM: rwsem.h need not be included into main.cRafael J. Wysocki
It is not necessary to include <linux/rwsem.h> into drivers/base/power/main.c, so don't do that. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2009-12-15PM: Remove unnecessary goto from device_resume_noirq()Rafael J. Wysocki
In device_resume_noirq() there is the 'End' label and the associated goto statement that aren't strictly necessary, so rework the code to get rid of them. Also modify device_suspend_noirq() so that it looks completely analogous to device_resume_noirq(). Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2009-12-15PM: Add initcall_debug style timing for suspend/resumeArjan van de Ven
In order to diagnose overall suspend/resume times, we need basic instrumentation to break down the total time into per device timing, similar to initcall_debug. This patch adds the basic timing instrumentation, needed for a scritps/bootgraph.pl equivalent or humans. The bootgraph.pl program is still a work in progress, but is far enough along to know that this patch is sufficient. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2009-11-03PM: Fix warning on suspend errorsRomit Dasgupta
Fixes the point where we need to complete the power transition when device suspend fails, so that we don't print warnings about devices added to the device hierarchy after a failing suspend. [rjw: Modified changelog.] Signed-off-by: Romit Dasgupta <romit@ti.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2009-09-14PM: Reset transition_started at dpm_resume_noirqXiaotian Feng
transition_started should be set once the preparation of devices for a PM has started, reset before starting to resume devices. When resuming devices, kernel calls dpm_resume_noirq then dpm_resume_end(dpm_resume). Thus we should reset transition_started at dpm_resume_noirq. This patch fixes ACPI warning when resuming from suspend/hibernate: ACPI: \_SB_.PCI0.IDE1.PRI1.MAS1 - docking ------------[ cut here ]------------ WARNING: at drivers/base/power/main.c:87 device_pm_add+0x8b/0xcc() Hardware name: OptiPlex 760 Device: acpi Parentless device registered during a PM transaction [rjw: Fixed up the changelog.] Signed-off-by: Xiaotian Feng <dfeng@redhat.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2009-09-14PM: Update kerneldoc comments in drivers/base/power/main.cRafael J. Wysocki
The kerneldoc comments in drivers/base/power/main.c are generally outdated and some of them don't describe the functions very accurately. Update them and standardize the format to use spaces instead of tabs. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Randy Dunlap <randy.dunlap@oracle.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Acked-by: Alan Stern <stern@rowland.harvard.edu>
2009-08-23PM: Introduce core framework for run-time PM of I/O devices (rev. 17)Rafael J. Wysocki
Introduce a core framework for run-time power management of I/O devices. Add device run-time PM fields to 'struct dev_pm_info' and device run-time PM callbacks to 'struct dev_pm_ops'. Introduce a run-time PM workqueue and define some device run-time PM helper functions at the core level. Document all these things. Special thanks to Alan Stern for his help with the design and multiple detailed reviews of the pereceding versions of this patch and to Magnus Damm for testing feedback. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Magnus Damm <damm@igel.co.jp>
2009-07-24Driver Core: Make PM operations a const pointerDmitry Torokhov
They are not supposed to be modified by drivers, so make them const. Signed-off-by: Dmitry Torokhov <dtor@mail.ru> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2009-07-08PM: Clear -EAGAIN in dpm_prepareSebastian Ott
When the last device in the dpm list is unregistered directly after its prepare() callback returned with -EAGAIN, the return code is passed to the calling function, resulting in a suspend failure. Prevent this by clearing the return code after -EAGAIN. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2009-06-12PM: Remove device_type suspend()/resume()Magnus Damm
This patch removes the legacy callbacks ->suspend() and ->resume() from struct device_type. These callbacks seem unused, and new code should instead make use of struct dev_pm_ops. Signed-off-by: Magnus Damm <damm@igel.co.jp> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2009-06-12PM: Remove bus_type suspend_late()/resume_early() V2Magnus Damm
Remove the ->suspend_late() and ->resume_early() callbacks from struct bus_type V2. These callbacks are legacy stuff at this point and since there seem to be no in-tree users we may as well remove them. New users should use dev_pm_ops. Signed-off-by: Magnus Damm <damm@igel.co.jp> Acked-by: Pavel Machek <pavel@ucw.cz> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2009-06-12PM core: rename suspend and resume functionsAlan Stern
This patch (as1241) renames a bunch of functions in the PM core. Rather than go through a boring list of name changes, suffice it to say that in the end we have a bunch of pairs of functions: device_resume_noirq dpm_resume_noirq device_resume dpm_resume device_complete dpm_complete device_suspend_noirq dpm_suspend_noirq device_suspend dpm_suspend device_prepare dpm_prepare in which device_X does the X operation on a single device and dpm_X invokes device_X for all devices in the dpm_list. In addition, the old dpm_power_up and device_resume_noirq have been combined into a single function (dpm_resume_noirq). Lastly, dpm_suspend_start and dpm_resume_end are the renamed versions of the former top-level device_suspend and device_resume routines. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Acked-by: Magnus Damm <damm@igel.co.jp> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2009-06-12PM: Rename device_power_down/up()Magnus Damm
Rename the functions performing "_noirq" dev_pm_ops operations from device_power_down() and device_power_up() to device_suspend_noirq() and device_resume_noirq(). The new function names are chosen to show that the functions are responsible for calling the _noirq() versions to finalize the suspend/resume operation. The current function names do not perform power down/up anymore so the names may be misleading. Global function renames: - device_power_down() -> device_suspend_noirq() - device_power_up() -> device_resume_noirq() Static function renames: - suspend_device_noirq() -> __device_suspend_noirq() - resume_device_noirq() -> __device_resume_noirq() Signed-off-by: Magnus Damm <damm@igel.co.jp> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Acked-by: Len Brown <lenb@kernel.org> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2009-05-24PM: Do not hold dpm_list_mtx while disabling/enabling nonboot CPUsRafael J. Wysocki
We shouldn't hold dpm_list_mtx while executing [disable|enable]_nonboot_cpus(), because theoretically this may lead to a deadlock as shown by the following example (provided by Johannes Berg): CPU 3 CPU 2 CPU 1 suspend/hibernate something: rtnl_lock() device_pm_lock() -> mutex_lock(&dpm_list_mtx) mutex_lock(&dpm_list_mtx) linkwatch_work -> rtnl_lock() disable_nonboot_cpus() -> flush CPU 3 workqueue Fortunately, device drivers are supposed to stop any activities that might lead to the registration of new device objects way before disable_nonboot_cpus() is called, so it shouldn't be necessary to hold dpm_list_mtx over the entire late part of device suspend and early part of device resume. Thus, during the late suspend and the early resume of devices acquire dpm_list_mtx only when dpm_list is going to be traversed and release it right after that. This patch is reported to fix the regressions tracked as http://bugzilla.kernel.org/show_bug.cgi?id=13245. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Alan Stern <stern@rowland.harvard.edu> Reported-by: Miles Lane <miles.lane@gmail.com> Tested-by: Ming Lei <tom.leiming@gmail.com>
2009-03-30PM: Rework handling of interrupts during suspend-resumeRafael J. Wysocki
Use the functions introduced in by the previous patch, suspend_device_irqs(), resume_device_irqs() and check_wakeup_irqs(), to rework the handling of interrupts during suspend (hibernation) and resume. Namely, interrupts will only be disabled on the CPU right before suspending sysdevs, while device drivers will be prevented from receiving interrupts, with the help of the new helper function, before their "late" suspend callbacks run (and analogously during resume). In addition, since the device interrups are now disabled before the CPU has turned all interrupts off and the CPU will ACK the interrupts setting the IRQ_PENDING bit for them, check in sysdev_suspend() if any wake-up interrupts are pending and abort suspend if that's the case. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Ingo Molnar <mingo@elte.hu>
2009-03-24Driver core: Fix device_move() vs. dpm list ordering, v2Cornelia Huck
dpm_list currently relies on the fact that child devices will be registered after their parents to get a correct suspend order. Using device_move() however destroys this assumption, as an already registered device may be moved under a newly registered one. This patch adds a new argument to device_move(), allowing callers to specify how dpm_list should be adapted. Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-02-22PM: Split up sysdev_[suspend|resume] from device_power_[down|up]Rafael J. Wysocki
Move the sysdev_suspend/resume from the callee to the callers, with no real change in semantics, so that we can rework the disabling of interrupts during suspend/hibernation. This is based on an earlier patch from Linus. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06driver core: struct device - replace bus_id with dev_name(), dev_set_name()Kay Sievers
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-01-06PM: Simplify the new suspend/hibernation framework for devicesRafael J. Wysocki
PM: Simplify the new suspend/hibernation framework for devices Following the discussion at the Kernel Summit, simplify the new device PM framework by merging 'struct pm_ops' and 'struct pm_ext_ops' and removing pointers to 'struct pm_ext_ops' from 'struct platform_driver' and 'struct pci_driver'. After this change, the suspend/hibernation callbacks will only reside in 'struct device_driver' as well as at the bus type/ device class/device type level. Accordingly, PCI and platform device drivers are now expected to put their suspend/hibernation callbacks into the 'struct device_driver' embedded in 'struct pci_driver' or 'struct platform_driver', respectively. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Pavel Machek <pavel@suse.cz> Cc: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-10-16Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6: (46 commits) UIO: Fix mapping of logical and virtual memory UIO: add automata sercos3 pci card support UIO: Change driver name of uio_pdrv UIO: Add alignment warnings for uio-mem Driver core: add bus_sort_breadthfirst() function NET: convert the phy_device file to use bus_find_device_by_name kobject: Cleanup kobject_rename and !CONFIG_SYSFS kobject: Fix kobject_rename and !CONFIG_SYSFS sysfs: Make dir and name args to sysfs_notify() const platform: add new device registration helper sysfs: use ilookup5() instead of ilookup5_nowait() PNP: create device attributes via default device attributes Driver core: make bus_find_device_by_name() more robust usb: turn dev_warn+WARN_ON combos into dev_WARN debug: use dev_WARN() rather than WARN_ON() in device_pm_add() debug: Introduce a dev_WARN() function sysfs: fix deadlock device model: Do a quickcheck for driver binding before doing an expensive check Driver core: Fix cleanup in device_create_vargs(). Driver core: Clarify device cleanup. ...
2008-10-16vsprintf: use new vsprintf symbolic function pointer formatBjorn Helgaas
Use the '%pF' format to get rid of an "#ifdef DEBUG" and make some printks atomic. This removes the last in-tree uses of print_fn_descriptor_symbol(). I marked print_fn_descriptor_symbol() deprecated and scheduled it for removal next year to give time for out-of-tree modules to be updated. parisc's print_fn_descriptor_symbol() is currently broken there (it needs to dereference the function pointer similar to ia64 and power). This patch shouldn't make anything worse, but it means we need to fix dereference_function_descriptor() instead of print_fn_descriptor_symbol() to get meaningful initcall_debug output. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: Jesse Barnes <jbarnes@virtuousgeek.org> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16debug: use dev_WARN() rather than WARN_ON() in device_pm_add()Arjan van de Ven
device_pm_add() has a WARN_ON that is showing relatively high on kerneloops.org, but unfortunately the WARN_ON is less than useful in that it doesn't print any information about what device is causing the issue. This patch fixes this by turning the WARN_ON() into the newly introduces dev_WARN() which will print information about the device in question. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-08-21PM: Remove WARN_ON from device_pm_addRafael J. Wysocki
PM: Remove WARN_ON from device_pm_add Fix message in device_pm_add() saying that the device will not be added to dpm_list, although in fact the device is going to be added to the list regardless of the ordering violation. Remove the WARN_ON(true) triggered in that situation, because it is hit by USB very often and spams the users' logs. This patch fixes bug #11263 Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-08-21PM: don't skip device PM init when CONFIG_PM_SLEEP isn't set and CONFIG_PM ↵Alan Stern
is set This patch (as1124) fixes a couple of bugs in the PM core. The new dev->power.status field should be initialized regardless of whether CONFIG_PM_SLEEP is enabled, and similarly dpm_sysfs_add() should be called whenever CONFIG_PM is enabled. The patch separates out the call to dpm_sysfs_add() from the call to device_pm_add(). As a result device_pm_add() can no longer return an error, so its return type is changed to void. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Tested-by: Romit Dasgupta <romit@ti.com> Acked-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-06-12Suspend-related patches for 2.6.27Rafael J. Wysocki
ACPI PM: Add possibility to change suspend sequence There are some systems out there that don't work correctly with our current suspend/hibernation code ordering. Provide a workaround for these systems allowing them to pass 'acpi_sleep=old_ordering' in the kernel command line so that it will use the pre-ACPI 2.0 ("old") suspend code ordering. Unfortunately, this requires us to add a platform hook to the resuming of devices for recovering the platform in case one of the device drivers' .suspend() routines returns error code. Namely, ACPI 1.0 specifies that _PTS should be called before suspending devices, but _WAK still should be called before resuming them in order to undo the changes made by _PTS. However, if there is an error during suspending devices, they are automatically resumed without returning control to the PM core, so the _WAK has to be called from within device_resume() in that cases. The patch also reorders and refactors the ACPI suspend/hibernation code to avoid duplication as far as reasonably possible. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Pavel Machek <pavel@suse.cz> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2008-06-10Introduce new top level suspend and hibernation callbacksRafael J. Wysocki
Introduce 'struct pm_ops' and 'struct pm_ext_ops' ('ext' meaning 'extended') representing suspend and hibernation operations for bus types, device classes, device types and device drivers. Modify the PM core to use 'struct pm_ops' and 'struct pm_ext_ops' objects, if defined, instead of the ->suspend(), ->resume(), ->suspend_late(), and ->resume_early() callbacks (the old callbacks will be considered as legacy and gradually phased out). The main purpose of doing this is to separate suspend (aka S2RAM and standby) callbacks from hibernation callbacks in such a way that the new callbacks won't take arguments and the semantics of each of them will be clearly specified. This has been requested for multiple times by many people, including Linus himself, and the reason is that within the current scheme if ->resume() is called, for example, it's difficult to say why it's been called (ie. is it a resume from RAM or from hibernation or a suspend/hibernation failure etc.?). The second purpose is to make the suspend/hibernation callbacks more flexible so that device drivers can handle more than they can within the current scheme. For example, some drivers may need to prevent new children of the device from being registered before their ->suspend() callbacks are executed or they may want to carry out some operations requiring the availability of some other devices, not directly bound via the parent-child relationship, in order to prepare for the execution of ->suspend(), etc. Ultimately, we'd like to stop using the freezing of tasks for suspend and therefore the drivers' suspend/hibernation code will have to take care of the handling of the user space during suspend/hibernation. That, in turn, would be difficult within the current scheme, without the new ->prepare() and ->complete() callbacks. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2008-05-15Clean up 'print_fn_descriptor_symbol()' typesLinus Torvalds
Everybody wants to pass it a function pointer, and in fact, that is what you _must_ pass it for it to make sense (since it knows that ia64 and ppc64 use descriptors for function pointers and fetches the actual address from there). So don't make the argument be a 'unsigned long' and force everybody to add a cast. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-22Relax check on adding children of suspended devicesRafael J. Wysocki
Do not refuse to actually register children of suspended devices, but still warn about attempts to do that. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>