Commit Graph

75 Commits

Author SHA1 Message Date
Rafael J. Wysocki
b64959e615 PM: Permit registration of parentless devices during system suspend
The registration of a new parentless device during system suspend
will not lead to any complications affecting the PM core (the device
will be effectively seen after the subsequent resume has completed),
so remove the code used for detection of such events.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-12-24 15:02:44 +01:00
Rafael J. Wysocki
b8c76f6aed PM: Replace the device power.status field with a bit field
The device power.status field is too complicated for its purpose
(storing the information about whether or not the device is in the
"active" state from the PM core's point of view), so replace it with
a bit field and modify all of its users accordingly.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-12-24 15:02:44 +01:00
Rafael J. Wysocki
5b219a51fd PM: Remove redundant checks from core device resume routines
Since a separate list of devices is used to link devices that have
completed each stage of suspend (or resume), it is not necessary to
check dev->power.status in the core device resume routines any more.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-12-24 15:02:43 +01:00
Rafael J. Wysocki
8a43a9ab7b PM: Use a different list of devices for each stage of device suspend
Instead of keeping all devices in the same list during system suspend
and resume, regardless of what suspend-resume callbacks have been
executed for them already, use separate lists of devices that have
had their ->prepare(), ->suspend() and ->suspend_noirq() callbacks
executed.  This will allow us to simplify the core device suspend and
resume routines.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-12-24 15:02:43 +01:00
Rafael J. Wysocki
2cbb3ce1ad PM: Avoid compiler warning in pm_noirq_op()
The compiler complains that calltime may be uninitialized in
pm_noirq_op(), so add extra initialization for that variable to
avoid the warning.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-12-24 15:02:42 +01:00
Rafael J. Wysocki
d83f905e12 PM: Use pm_wakeup_pending() in __device_suspend()
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>
2010-12-24 15:02:42 +01:00
Rafael J. Wysocki
a2867e08c8 PM / Wakeup: Replace pm_check_wakeup_events() with pm_wakeup_pending()
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>
2010-12-24 15:02:42 +01:00
Rafael J. Wysocki
1e75227ef0 PM: Prevent dpm_prepare() from returning errors unnecessarily
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>
2010-12-24 15:02:41 +01:00
Rafael J. Wysocki
d08a5ace18 PM: Allow devices to be removed during late suspend and early resume
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>
2010-11-11 01:50:53 +01:00
Rafael J. Wysocki
098dff738a PM: Fix potential issue with failing asynchronous suspend
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>
2010-10-17 01:57:43 +02:00
Rafael J. Wysocki
074037ec79 PM / Wakeup: Introduce wakeup source objects and event statistics (v3)
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>
2010-10-17 01:57:43 +02:00
Kevin Cernekee
0702d9ee0f PM: Fix signed/unsigned warning in dpm_show_time()
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>
2010-10-17 01:57:43 +02:00
Colin Cross
152e1d5920 PM: Prevent waiting forever on asynchronous resume after failing suspend
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>
2010-09-09 00:49:43 +02:00
Rafael J. Wysocki
c125e96f04 PM: Make it possible to avoid races between wakeup and system sleep
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>
2010-07-19 01:58:48 +02:00
Dominik Brodowski
e7176a37d4 power: support _noirq actions on device types and classes
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>
2010-03-24 11:00:02 +01:00
Greg Kroah-Hartman
8e9394ce24 Driver core: create lock/unlock functions for struct device
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>
2010-03-07 17:04:52 -08:00
Rafael J. Wysocki
f8824cee40 PM: Allow device drivers to use dpm_wait()
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>
2010-02-26 20:39:11 +01:00
Rafael J. Wysocki
97df8c1299 PM: Start asynchronous resume threads upfront
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>
2010-02-26 20:39:11 +01:00
Rafael J. Wysocki
0e06b4a891 PM: Add a switch for disabling/enabling asynchronous suspend/resume
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>
2010-02-26 20:39:10 +01:00
Rafael J. Wysocki
5af84b8270 PM: Asynchronous suspend and resume of devices
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>
2010-02-26 20:39:09 +01:00
Rafael J. Wysocki
8cc6b39ff3 PM: Add parent information to timing messages
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>
2010-02-26 20:39:09 +01:00
Randy Dunlap
0a88422312 power: fix kernel-doc notation
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>
2010-01-11 09:34:06 -08:00
Alan Stern
aa0baaef97 PM: Use pm_runtime_put_sync in system resume
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>
2009-12-21 02:46:11 +01:00
Rafael J. Wysocki
ecf762b258 PM: Measure device suspend and resume times
Measure and print the time of suspending and resuming all devices.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2009-12-18 01:57:47 +01:00
Rafael J. Wysocki
875ab0b74e PM: Make the initcall_debug style timing for suspend/resume complete
Commit f251177486
(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>
2009-12-18 01:57:31 +01:00
Rafael J. Wysocki
d8bed5a4f3 PM: rwsem.h need not be included into main.c
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>
2009-12-15 20:42:06 +01:00
Rafael J. Wysocki
33c3374031 PM: Remove unnecessary goto from device_resume_noirq()
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>
2009-12-15 20:42:06 +01:00
Arjan van de Ven
f251177486 PM: Add initcall_debug style timing for suspend/resume
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>
2009-12-15 20:42:06 +01:00
Romit Dasgupta
e528e87689 PM: Fix warning on suspend errors
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>
2009-11-03 11:03:33 +01:00
Xiaotian Feng
3eb132c986 PM: Reset transition_started at dpm_resume_noirq
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>
2009-09-14 20:27:00 +02:00
Rafael J. Wysocki
20d652d7d1 PM: Update kerneldoc comments in drivers/base/power/main.c
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>
2009-09-14 20:27:00 +02:00
Rafael J. Wysocki
5e928f77a0 PM: Introduce core framework for run-time PM of I/O devices (rev. 17)
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>
2009-08-23 00:04:44 +02:00
Dmitry Torokhov
d9ab77161d Driver Core: Make PM operations a const pointer
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>
2009-07-24 00:17:28 +02:00
Sebastian Ott
886a7a3371 PM: Clear -EAGAIN in dpm_prepare
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>
2009-07-08 13:26:05 +02:00
Magnus Damm
0072578751 PM: Remove device_type suspend()/resume()
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>
2009-06-12 21:32:32 +02:00
Magnus Damm
e240b58c79 PM: Remove bus_type suspend_late()/resume_early() V2
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>
2009-06-12 21:32:31 +02:00
Alan Stern
d161630297 PM core: rename suspend and resume functions
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>
2009-06-12 21:32:31 +02:00
Magnus Damm
e39a71ef80 PM: Rename device_power_down/up()
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>
2009-06-12 21:32:31 +02:00
Rafael J. Wysocki
32bdfac546 PM: Do not hold dpm_list_mtx while disabling/enabling nonboot CPUs
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>
2009-05-24 21:15:07 +02:00
Rafael J. Wysocki
2ed8d2b3a8 PM: Rework handling of interrupts during suspend-resume
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>
2009-03-30 21:46:54 +02:00
Cornelia Huck
ffa6a7054d Driver core: Fix device_move() vs. dpm list ordering, v2
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>
2009-03-24 16:38:26 -07:00
Rafael J. Wysocki
770824bdc4 PM: Split up sysdev_[suspend|resume] from device_power_[down|up]
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>
2009-02-22 10:33:44 -08:00
Kay Sievers
1e0b2cf933 driver core: struct device - replace bus_id with dev_name(), dev_set_name()
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-01-06 10:44:31 -08:00
Rafael J. Wysocki
adf094931f PM: Simplify the new suspend/hibernation framework for devices
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>
2009-01-06 10:44:29 -08:00
Linus Torvalds
c813b4e16e Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6
* 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.
  ...
2008-10-16 12:40:26 -07:00
Bjorn Helgaas
c80cfb0406 vsprintf: use new vsprintf symbolic function pointer format
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>
2008-10-16 11:21:31 -07:00
Arjan van de Ven
728f08934b debug: use dev_WARN() rather than WARN_ON() in device_pm_add()
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>
2008-10-16 09:24:50 -07:00
Rafael J. Wysocki
f5a6d958b5 PM: Remove WARN_ON from device_pm_add
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>
2008-08-21 10:15:37 -07:00
Alan Stern
3b98aeaf3a PM: don't skip device PM init when CONFIG_PM_SLEEP isn't set and CONFIG_PM 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>
2008-08-21 10:15:36 -07:00
Rafael J. Wysocki
d8f3de0d24 Suspend-related patches for 2.6.27
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>
2008-06-12 14:25:09 -07:00