commit b9ea0bae260f6aae546db224daa6ac1bd9d94b91 upstream.

Certain ACPI-enumerated devices represented as platform devices in
Linux, like fans, require special low-level power management handling
implemented by their drivers that is not in agreement with the ACPI
PM domain behavior.  That leads to problems with managing ACPI fans
during system-wide suspend and resume.

For this reason, make acpi_dev_pm_attach() skip the affected devices
by adding a list of device IDs to avoid to it and putting the IDs of
the affected devices into that list.

Fixes: e5cc8ef3 (ACPI / PM: Provide ACPI PM callback routines for subsystems)
Reported-by: NZhang Rui <rui.zhang@intel.com>
Tested-by: NTodd Brandt <todd.e.brandt@linux.intel.com>
Cc: 3.10+ <stable@vger.kernel.org> # 3.10+
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit 9a51c6b1f9e0239a9435db036b212498a2a3b75c ]

Both acpi_pci_need_resume() and acpi_dev_needs_resume() check if the
current ACPI wakeup configuration of the device matches what is
expected as far as system wakeup from sleep states is concerned, as
reflected by the device_may_wakeup() return value for the device.

However, they only should do that if wakeup.flags.valid is set for
the device's ACPI companion, because otherwise the wakeup.prepare_count
value for it is meaningless.

Add the missing wakeup.flags.valid checks to these functions.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NSasha Levin <sashal@kernel.org>

The callers of dev_pm_domain_attach() currently checks the returned error
code for -EPROBE_DEFER and needs to ignore other error codes. This is an
unnecessary limitation, which also leads to a rather strange behaviour in
the error path.

Address this limitation, by changing the return codes from
acpi_dev_pm_attach() and genpd_dev_pm_attach(). More precisely, let them
return 0, when no PM domain is needed for the device and then return 1, in
case the device was successfully attached to its PM domain. In this way,
dev_pm_domain_attach(), gets a better understanding of what happens in the
attach attempts and also allowing its caller to better act on real errors
codes.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Instead of checking if an existing PM domain pointer has been assigned in
genpd_dev_pm_attach() and acpi_dev_pm_attach(), move the check to the
common path in dev_pm_domain_attach(), thus potentially avoid one
unnecessary check.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

acpi_dev_pm_get_state() is used to determine the range of allowable
device power states when going into S3 suspend. This is implemented
by executing the _S3D and _S3W ACPI methods.

Linux follows the ACPI spec behaviour in that when _S3D is implemented
and _S3W is not, Linux will not go into a power state deeper than the one
returned by _S3D for a wakeup-enabled device.

However, this same logic is being applied to the case when neither
_S3D nor _S3W are present, and the result is that this function
decides that the device must stay in D0 (fully on) state.

This is breaking USB wakeups on Asus V222GA and Acer XC-830. _S3D and
_S3W are not present, so the USB controller is left in the D0 running
state during S3, and hence it is unable to generate a PME# wake event.

The ACPI spec is unclear on which power states are permissable for
wakeup-enabled devices when both _S3D and _S3W are missing.
However, USB wakeups work fine on these platforms under Windows, where
device manager shows that they are using D3 device state for the USB
controller in S3.

I assume that the "max = min" clamping done by the code here is
specifically written for the _S3D but no _S3W case. By making the
code true to those conditions, avoiding them on these platforms,
the controller will be put into D3 state and USB wakeups start working.

Additionally I feel that this change makes the code more directly
mirror the wording of the ACPI spec and it's associated lack of clarity.

Thanks to Mathias Nyman for pointing us in the right direction.
Signed-off-by: NDaniel Drake <drake@endlessm.com>
Link: http://lkml.kernel.org/r/CAB4CAwf_k-WsF3zL4epm9TKAOu0h=Bv1XhXV_gY3bziOo_NPKA@mail.gmail.com

https://phabricator.endlessm.com/T21410Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Middle-layer code doing suspend-time optimizations for devices with
the DPM_FLAG_SMART_SUSPEND flag set (currently, the PCI bus type and
the ACPI PM domain) needs to make the core skip ->thaw_early and
->thaw callbacks for those devices in some cases and it sets the
power.direct_complete flag for them for this purpose.

However, it turns out that setting power.direct_complete outside of
the PM core is a bad idea as it triggers an excess invocation of
pm_runtime_enable() in device_resume().

For this reason, provide a helper to clear power.is_late_suspended
and power.is_suspended to be invoked by the middle-layer code in
question instead of setting power.direct_complete and make that code
call the new helper.

Fixes: c4b65157 (PCI / PM: Take SMART_SUSPEND driver flag into account)
Fixes: 05087360 (ACPI / PM: Take SMART_SUSPEND driver flag into account)
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: NUlf Hansson <ulf.hansson@linaro.org>
Acked-by: NBjorn Helgaas <bhelgaas@google.com>

Add support for DPM_FLAG_LEAVE_SUSPENDED to the ACPI PM domain by
making it (a) set the power.may_skip_resume status bit for devices
that, from its perspective, may be left in suspend after system
wakeup from sleep and (b) return early from acpi_subsys_resume_noirq()
for devices whose remaining resume callbacks during the transition
under way are going to be skipped by the PM core.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

acpi_remove_pm_notifier() ends up calling flush_workqueue() while
holding acpi_pm_notifier_lock, and that same lock is taken by
by the work via acpi_pm_notify_handler(). This can deadlock.

To fix the problem let's split the single lock into two: one to
protect the dev->wakeup between the work vs. add/remove, and
another one to handle notifier installation vs. removal.

After commit a1d14934 "workqueue/lockdep: 'Fix' flush_work()
annotation" I was able to kill the machine (Intel Braswell)
very easily with 'powertop --auto-tune', runtime suspending i915,
and trying to wake it up via the USB keyboard. The cases when
it didn't die are presumably explained by lockdep getting disabled
by something else (cpu hotplug locking issues usually).

Fortunately I still got a lockdep report over netconsole
(trickling in very slowly), even though the machine was
otherwise practically dead:

[  112.179806] ======================================================
[  114.670858] WARNING: possible circular locking dependency detected
[  117.155663] 4.13.0-rc6-bsw-bisect-00169-ga1d14934 #119 Not tainted
[  119.658101] ------------------------------------------------------
[  121.310242] xhci_hcd 0000:00:14.0: xHCI host not responding to stop endpoint command.
[  121.313294] xhci_hcd 0000:00:14.0: xHCI host controller not responding, assume dead
[  121.313346] xhci_hcd 0000:00:14.0: HC died; cleaning up
[  121.313485] usb 1-6: USB disconnect, device number 3
[  121.313501] usb 1-6.2: USB disconnect, device number 4
[  134.747383] kworker/0:2/47 is trying to acquire lock:
[  137.220790]  (acpi_pm_notifier_lock){+.+.}, at: [<ffffffff813cafdf>] acpi_pm_notify_handler+0x2f/0x80
[  139.721524]
[  139.721524] but task is already holding lock:
[  144.672922]  ((&dpc->work)){+.+.}, at: [<ffffffff8109ce90>] process_one_work+0x160/0x720
[  147.184450]
[  147.184450] which lock already depends on the new lock.
[  147.184450]
[  154.604711]
[  154.604711] the existing dependency chain (in reverse order) is:
[  159.447888]
[  159.447888] -> #2 ((&dpc->work)){+.+.}:
[  164.183486]        __lock_acquire+0x1255/0x13f0
[  166.504313]        lock_acquire+0xb5/0x210
[  168.778973]        process_one_work+0x1b9/0x720
[  171.030316]        worker_thread+0x4c/0x440
[  173.257184]        kthread+0x154/0x190
[  175.456143]        ret_from_fork+0x27/0x40
[  177.624348]
[  177.624348] -> #1 ("kacpi_notify"){+.+.}:
[  181.850351]        __lock_acquire+0x1255/0x13f0
[  183.941695]        lock_acquire+0xb5/0x210
[  186.046115]        flush_workqueue+0xdd/0x510
[  190.408153]        acpi_os_wait_events_complete+0x31/0x40
[  192.625303]        acpi_remove_notify_handler+0x133/0x188
[  194.820829]        acpi_remove_pm_notifier+0x56/0x90
[  196.989068]        acpi_dev_pm_detach+0x5f/0xa0
[  199.145866]        dev_pm_domain_detach+0x27/0x30
[  201.285614]        i2c_device_probe+0x100/0x210
[  203.411118]        driver_probe_device+0x23e/0x310
[  205.522425]        __driver_attach+0xa3/0xb0
[  207.634268]        bus_for_each_dev+0x69/0xa0
[  209.714797]        driver_attach+0x1e/0x20
[  211.778258]        bus_add_driver+0x1bc/0x230
[  213.837162]        driver_register+0x60/0xe0
[  215.868162]        i2c_register_driver+0x42/0x70
[  217.869551]        0xffffffffa0172017
[  219.863009]        do_one_initcall+0x45/0x170
[  221.843863]        do_init_module+0x5f/0x204
[  223.817915]        load_module+0x225b/0x29b0
[  225.757234]        SyS_finit_module+0xc6/0xd0
[  227.661851]        do_syscall_64+0x5c/0x120
[  229.536819]        return_from_SYSCALL_64+0x0/0x7a
[  231.392444]
[  231.392444] -> #0 (acpi_pm_notifier_lock){+.+.}:
[  235.124914]        check_prev_add+0x44e/0x8a0
[  237.024795]        __lock_acquire+0x1255/0x13f0
[  238.937351]        lock_acquire+0xb5/0x210
[  240.840799]        __mutex_lock+0x75/0x940
[  242.709517]        mutex_lock_nested+0x1c/0x20
[  244.551478]        acpi_pm_notify_handler+0x2f/0x80
[  246.382052]        acpi_ev_notify_dispatch+0x44/0x5c
[  248.194412]        acpi_os_execute_deferred+0x14/0x30
[  250.003925]        process_one_work+0x1ec/0x720
[  251.803191]        worker_thread+0x4c/0x440
[  253.605307]        kthread+0x154/0x190
[  255.387498]        ret_from_fork+0x27/0x40
[  257.153175]
[  257.153175] other info that might help us debug this:
[  257.153175]
[  262.324392] Chain exists of:
[  262.324392]   acpi_pm_notifier_lock --> "kacpi_notify" --> (&dpc->work)
[  262.324392]
[  267.391997]  Possible unsafe locking scenario:
[  267.391997]
[  270.758262]        CPU0                    CPU1
[  272.431713]        ----                    ----
[  274.060756]   lock((&dpc->work));
[  275.646532]                                lock("kacpi_notify");
[  277.260772]                                lock((&dpc->work));
[  278.839146]   lock(acpi_pm_notifier_lock);
[  280.391902]
[  280.391902]  *** DEADLOCK ***
[  280.391902]
[  284.986385] 2 locks held by kworker/0:2/47:
[  286.524895]  #0:  ("kacpi_notify"){+.+.}, at: [<ffffffff8109ce90>] process_one_work+0x160/0x720
[  288.112927]  #1:  ((&dpc->work)){+.+.}, at: [<ffffffff8109ce90>] process_one_work+0x160/0x720
[  289.727725]

Fixes: c072530f (ACPI / PM: Revork the handling of ACPI device wakeup notifications)
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Cc: 3.17+ <stable@vger.kernel.org> # 3.17+
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Make the ACPI PM domain take DPM_FLAG_SMART_SUSPEND into account in
its system suspend callbacks.

[Note that the pm_runtime_suspended() check in acpi_dev_needs_resume()
is an optimization, because if is not passed, all of the subsequent
checks may be skipped and some of them are much more overhead in
general.]

Also use the observation that if the device is in runtime suspend
at the beginning of the "late" phase of a system-wide suspend-like
transition, its state cannot change going forward (runtime PM is
disabled for it at that time) until the transition is over and the
subsequent system-wide PM callbacks should be skipped for it (as
they generally assume the device to not be suspended), so add
checks for that in acpi_subsys_suspend_late/noirq() and
acpi_subsys_freeze_late/noirq().

Moreover, if acpi_subsys_resume_noirq() is called during the
subsequent system-wide resume transition and if the device was left
in runtime suspend previously, its runtime PM status needs to be
changed to "active" as it is going to be put into the full-power
state going forward, so add a check for that too in there.

In turn, if acpi_subsys_thaw_noirq() runs after the device has been
left in runtime suspend, the subsequent "thaw" callbacks need
to be skipped for it (as they may not work correctly with a
suspended device), so set the power.direct_complete flag for the
device then to make the PM core skip those callbacks.

On top of the above, make the analogous changes in the acpi_lpss
driver that uses the ACPI PM domain callbacks.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The motivation for this change is to provide a way to work around
a problem with the direct-complete mechanism used for avoiding
system suspend/resume handling for devices in runtime suspend.

The problem is that some middle layer code (the PCI bus type and
the ACPI PM domain in particular) returns positive values from its
system suspend ->prepare callbacks regardless of whether the driver's
->prepare returns a positive value or 0, which effectively prevents
drivers from being able to control the direct-complete feature.
Some drivers need that control, however, and the PCI bus type has
grown its own flag to deal with this issue, but since it is not
limited to PCI, it is better to address it by adding driver flags at
the core level.

To that end, add a driver_flags field to struct dev_pm_info for flags
that can be set by device drivers at the probe time to inform the PM
core and/or bus types, PM domains and so on on the capabilities and/or
preferences of device drivers.  Also add two static inline helpers
for setting that field and testing it against a given set of flags
and make the driver core clear it automatically on driver remove
and probe failures.

Define and document two PM driver flags related to the direct-
complete feature: NEVER_SKIP and SMART_PREPARE that can be used,
respectively, to indicate to the PM core that the direct-complete
mechanism should never be used for the device and to inform the
middle layer code (bus types, PM domains etc) that it can only
request the PM core to use the direct-complete mechanism for
the device (by returning a positive value from its ->prepare
callback) if it also has been requested by the driver.

While at it, make the core check pm_runtime_suspended() when
setting power.direct_complete so that it doesn't need to be
checked by ->prepare callbacks.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NUlf Hansson <ulf.hansson@linaro.org>

On top of a previous change getting rid of the PM QoS flag
PM_QOS_FLAG_REMOTE_WAKEUP, combine two ACPI device suspend routines,
acpi_dev_runtime_suspend() and acpi_dev_suspend_late(), into one,
acpi_dev_suspend(), to eliminate some code duplication.

It also avoids enabling wakeup for devices handled by the ACPI
LPSS middle layer on driver removal.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: NUlf Hansson <ulf.hansson@linaro.org>

The PM QoS flag PM_QOS_FLAG_REMOTE_WAKEUP is not used consistently
and the vast majority of code simply assumes that remote wakeup
should be enabled for devices in runtime suspend if they can
generate wakeup signals, so drop it.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: NUlf Hansson <ulf.hansson@linaro.org>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>

Move the code dealing with validation of whether runtime resuming the
device is needed during system suspend.

In this way it becomes more clear for what circumstances ACPI is prevented
from trying the direct_complete path.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Commit 58a1fbbb (PM / PCI / ACPI: Kick devices that might have
been reset by firmware), made PCI's and ACPI's ->complete() callbacks
to be assigned to a new API called pm_complete_with_resume_check(),
which was introduced in the same change.

Later it turned out that using pm_complete_with_resume_check() wasn't
good enough for PCI, as it needed additional PCI specific checks,
before deciding whether runtime resuming the device is needed when
running the ->complete() callback.

This leaves ACPI as the only user of pm_complete_with_resume_check().
Therefore let's restore ACPI's acpi_subsys_complete(), which was
dropped in commit 58a1fbbb (PM / PCI / ACPI: Kick devices that
might have been reset by firmware).

This enables us to remove the pm_complete_with_resume_check() API in
a following change, but it also enables ACPI to add more ACPI
specific checks in acpi_subsys_complete() if that turns out to be
necessary.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Notice that acpi_dev_runtime_resume() and acpi_dev_resume_early() are
actually literally identical after some more-or-less recent changes,
so rename acpi_dev_runtime_resume() to acpi_dev_resume(), use it
everywhere instead of acpi_dev_resume_early() and drop the latter.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: NUlf Hansson <ulf.hansson@linaro.org>

Add statements to trace invocations of the ACPI PM notify handler
and the work functions called by it.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The acpi_pci_propagate_wakeup() routine is there to handle cases in
which PCI bridges (or PCIe ports) are expected to signal wakeup
for devices below them, but currently it doesn't do that correctly.

The problem is that acpi_pci_propagate_wakeup() uses
acpi_pm_set_device_wakeup() for bridges and if that routine is
called for multiple times to disable wakeup for the same device,
it will disable it on the first invocation and the next calls
will have no effect (it works analogously when called to enable
wakeup, but that is not a problem).

Now, say acpi_pci_propagate_wakeup() has been called for two
different devices under the same bridge and it has called
acpi_pm_set_device_wakeup() for that bridge each time.  The
bridge is now enabled to generate wakeup signals.  Next,
suppose that one of the devices below it resumes and
acpi_pci_propagate_wakeup() is called to disable wakeup for that
device.  It will then call acpi_pm_set_device_wakeup() for the bridge
and that will effectively disable remote wakeup for all devices under
it even though some of them may still be suspended and remote wakeup
may be expected to work for them.

To address this (arguably theoretical) issue, allow
wakeup.enable_count under struct acpi_device to grow beyond 1 in
certain situations.  In particular, allow that to happen in
acpi_pci_propagate_wakeup() when wakeup is enabled or disabled
for PCI bridges, so that wakeup is actually disabled for the
bridge when all devices under it resume and not when just one
of them does that.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: NAndy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: NBjorn Helgaas <bhelgaas@google.com>

To prepare for a subsequent change and make the code somewhat easier
to follow, do the following in the ACPI device wakeup handling code:

 * Replace wakeup.flags.enabled under struct acpi_device with
   wakeup.enable_count as that will be necessary going forward.

   For now, wakeup.enable_count is not allowed to grow beyond 1,
   so the current behavior is retained.

 * Split acpi_device_wakeup() into acpi_device_wakeup_enable()
   and acpi_device_wakeup_disable() and modify the callers of
   it accordingly.

 * Introduce a new acpi_wakeup_lock mutex to protect the wakeup
   enabling/disabling code from races in case it is executed
   more than once in parallel for the same device (which may
   happen for bridges theoretically).
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>

The pme_interrupt flag in struct pci_dev is set when PMEs generated
by the device are going to be signaled via root port PME interrupts.

Ironically enough, that information is only used by the code setting
up device wakeup through ACPI which returns as soon as it sees the
pme_interrupt flag set while setting up "remote runtime wakeup".
That is questionable, however, because in theory there may be PCIe
devices using out-of-band PME signaling under root ports handled
by the native PME code or devices requiring wakeup power setup to be
carried out by AML.  For such devices, ACPI wakeup should be invoked
regardless of whether or not native PME signaling is used in general.

For this reason, drop the pme_interrupt flag and rework the code
using it which then allows the ACPI-based device wakeup handling
in PCI to be consolidated to use one code path for both "runtime
remote wakeup" and system wakeup (from sleep states).
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: NBjorn Helgaas <bhelgaas@google.com>

Currently, there are two separate ways of handling device wakeup
settings in the ACPI core, depending on whether this is runtime
wakeup or system wakeup (from sleep states).  However, after the
previous commit eliminating the run_wake ACPI device wakeup flag,
there is no difference between the two any more at the ACPI level,
so they can be combined.

For this reason, introduce acpi_pm_set_device_wakeup() to replace both
acpi_pm_device_run_wake() and acpi_pm_device_sleep_wake() and make it
check the ACPI device object's wakeup.valid flag to determine whether
or not the device can be set up to generate wakeup signals.

Also notice that zpodd_enable/disable_run_wake() only call
device_set_run_wake() because acpi_pm_device_run_wake() called
device_run_wake(), which is not done by acpi_pm_set_device_wakeup(),
so drop the now redundant device_set_run_wake() calls from there.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: NBjorn Helgaas <bhelgaas@google.com>

This will be needed in constifying the fwnode API.

The side effects the function had have been moved to the callers.
Signed-off-by: NSakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The ACPI SCI (System Control Interrupt) is set up as a wakeup IRQ
during suspend-to-idle transitions and, consequently, any events
signaled through it wake up the system from that state.  However,
on some systems some of the events signaled via the ACPI SCI while
suspended to idle should not cause the system to wake up.  In fact,
quite often they should just be discarded.

Arguably, systems should not resume entirely on such events, but in
order to decide which events really should cause the system to resume
and which are spurious, it is necessary to resume up to the point
when ACPI SCIs are actually handled and processed, which is after
executing dpm_resume_noirq() in the system resume path.

For this reasons, add a loop around freeze_enter() in which the
platforms can process events signaled via multiplexed IRQ lines
like the ACPI SCI and add suspend-to-idle hooks that can be
used for this purpose to struct platform_freeze_ops.

In the ACPI case, the ->wake hook is used for checking if the SCI
has triggered while suspended and deferring the interrupt-induced
system wakeup until the events signaled through it are actually
processed sufficiently to decide whether or not the system should
resume.  In turn, the ->sync hook allows all of the relevant event
queues to be flushed so as to prevent events from being missed due
to race conditions.

In addition to that, some ACPI code processing wakeup events needs
to be modified to use the "hard" version of wakeup triggers, so that
it will cause a system resume to happen on device-induced wakeup
events even if the "soft" mechanism to prevent the system from
suspending is not enabled.  However, to preserve the existing
behavior with respect to suspend-to-RAM, this only is done in
the suspend-to-idle case and only if an SCI has occurred while
suspended.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The wakeup.flags.enabled flag in struct acpi_device is not used
consistently, as there is no reason why it should only apply
to the enabling/disabling of the wakeup GPE, so put the invocation
of acpi_enable_wakeup_device_power() under it too.

Moreover, it is not necessary to call
acpi_enable_wakeup_devices() and acpi_disable_wakeup_devices() for
suspend-to-idle, so don't do that.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Change the log level of the "System wakeup enabled/disabled by ACPI"
message in acpi_pm_device_sleep_wake() to "debug" to reduce to log
noise level.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The work functions provided by the users of acpi_add_pm_notifier()
should be run synchronously before re-enabling the wakeup GPE in
case they are used to clear the status and/or disable the wakeup
signaling at the source.  Otherwise, which is the case currently in
the PCI bus type code, the same wakeup event may be signaled for
multiple times while the execution of the work function in response
to it has already been queued up.

Fortunately, acpi_add_pm_notifier() is only used by PCI and by
ACPI device PM code internally, so the change is relatively
straightforward to make.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: NBjorn Helgaas <bhelgaas@google.com>

Revert commit eed4d47e (ACPI / sleep: Ignore spurious SCI wakeups
from suspend-to-idle) as it turned out to be premature and triggered
a number of different issues on various systems.

That includes, but is not limited to, premature suspend-to-RAM aborts
on Dell XPS 13 (9343) reported by Dominik.

The issue the commit in question attempted to address is real and
will need to be taken care of going forward, but evidently more work
is needed for this purpose.
Reported-by: NDominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The ACPI SCI (System Control Interrupt) is set up as a wakeup IRQ
during suspend-to-idle transitions and, consequently, any events
signaled through it wake up the system from that state.  However,
on some systems some of the events signaled via the ACPI SCI while
suspended to idle should not cause the system to wake up.  In fact,
quite often they should just be discarded.

Arguably, systems should not resume entirely on such events, but in
order to decide which events really should cause the system to resume
and which are spurious, it is necessary to resume up to the point
when ACPI SCIs are actually handled and processed, which is after
executing dpm_resume_noirq() in the system resume path.

For this reasons, add a loop around freeze_enter() in which the
platforms can process events signaled via multiplexed IRQ lines
like the ACPI SCI and add suspend-to-idle hooks that can be
used for this purpose to struct platform_freeze_ops.

In the ACPI case, the ->wake hook is used for checking if the SCI
has triggered while suspended and deferring the interrupt-induced
system wakeup until the events signaled through it are actually
processed sufficiently to decide whether or not the system should
resume.  In turn, the ->sync hook allows all of the relevant event
queues to be flushed so as to prevent events from being missed due
to race conditions.

In addition to that, some ACPI code processing wakeup events needs
to be modified to use the "hard" version of wakeup triggers, so that
it will cause a system resume to happen on device-induced wakeup
events even if the "soft" mechanism to prevent the system from
suspending is not enabled (that also helps to catch device-induced
wakeup events occurring during suspend transitions in progress).
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Drivers that needs acpi_device_fix_up_power(), allow them to be built as
modules by exporting this function.

Cc: <stable@vger.kernel.org> # 4.5+
Tested-by: NLaszlo Fiat <laszlo.fiat@gmail.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Adds a function that sets the pointer to dev_pm_domain in struct device
and that warns if the device has already finished probing. The reason
why we want to enforce that is because in the general case that can
cause problems and also that we can simplify code quite a bit if we can
always assume that.

This patch also changes all current code that directly sets the
dev.pm_domain pointer.
Signed-off-by: NTomeu Vizoso <tomeu.vizoso@collabora.com>
Reviewed-by: NUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

There is a concern that if the platform firmware was involved in
the system resume that's being completed,  some devices might have
been reset by it and if those devices had the power.direct_complete
flag set during the preceding suspend transition, they may stay
in a reset-power-on state indefinitely (until they are runtime-resumed
and then suspended again).  That may not be a big deal from the
individual device's perspective, but if the system is an SoC, it may
be prevented from entering deep SoC-wide low-power states on idle
because of that.

The devices that are most likely to be affected by this issue are
PCI devices and ACPI-enumerated devices using the general ACPI PM
domain, so to prevent it from happening for those devices, force a
runtime resume for them if they have their power.direct_complete
flags set and the platform firmware was involved in the resume
transition currently in progress.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Commit 20dacb71 ("ACPI / PM: Rework device power management to follow
ACPI 6") changed the device power management to use D3hot if the device
in question does not have _PR3 method even if D3cold was requested by the
caller.

However, if the device has _PR3 device->power.state is also set to D3hot
instead of D3Cold after power resources have been turned off because
device->power.state will be assigned from "state" instead of
"target_state".

Next time the device is transitioned to D0, acpi_power_transition() will
find that the current power state of the device is D3hot instead of D3cold
which causes it to power down all resources required for the current
(wrong) state D3hot.

Below is a simplified ASL example of a real touch panel device which
triggers the problem:

  Scope (TPL1)
  {
      Name (_PR0, Package (1) { \_SB.PCI0.I2C1.PXTC })
      Name (_PR3, Package (1) { \_SB.PCI0.I2C1.PXTC })
      ...
  }

In both D0 and D3hot the same power resource is required. However, when
acpi_power_transition() turns off power resources required for D3hot (as
the device is transitioned to D0) it powers down PXTC which then makes the
device to lose its power.

Fix this by assigning "target_state" to the device power state instead of
"state" that is always D3hot even for devices with valid _PR3.

Fixes: 20dacb71 (ACPI / PM: Rework device power management to follow ACPI 6)
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Some devices, like MFD subdevices, share a single ACPI companion device so
that they are able to access their resources and children. However,
currently all these subdevices are attached to the ACPI power domain and
this might cause that the power methods for the companion device get called
more than once.

In order to solve this we attach the ACPI power domain only to the first
physical device that is bound to the ACPI companion device. In case of MFD
devices, this is the parent MFD device itself.
Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NLee Jones <lee.jones@linaro.org>

There is no need to carry potentially outdated Free Software Foundation
mailing address in file headers since the COPYING file includes it.
Signed-off-by: NJarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Add missing invocation of pm_generic_complete() to
acpi_subsys_complete() to allow ->complete callbacks provided
by the drivers of devices using the ACPI PM domain to be executed
during system resume.

Fixes: f25c0ae2 (ACPI / PM: Avoid resuming devices in ACPI PM domain during system suspend)
Cc: 3.16+ <stable@vger.kernel.org> # 3.16+
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The ACPI 6 specification has made some changes in the device power
management area.  In particular:

 * The D3hot power state is now supposed to be always available
   (instead of D3cold) and D3cold is only regarded as valid if the
   _PR3 object is present for the given device.

 * The required ordering of transitions into power states deeper than
   D0 is now such that for a transition into state Dx the _PSx method
   is supposed to be executed first, if present, and the states of
   the power resources the device depends on are supposed to be
   changed after that.

 * It is now explicitly forbidden to transition devices from
   lower-power (deeper) into higher-power (shallower) power states
   other than D0.

Those changes have been made so the specification reflects the
Windows' device power management code that the vast majority of
systems using ACPI is validated against.

To avoid artificial differences in ACPI device power management
between Windows and Linux, modify the ACPI device power management
code to follow the new specification.  Add comments explaining the
code flow in some unclear places.

This only may affect some real corner cases in which the OS behavior
expected by the firmware is different from the Windows one, but that's
quite unlikely.  The transition ordering change affects transitions
to D1 and D2 which are rarely used (if at all) and into D3hot and
D3cold for devices actually having _PR3, but those are likely to
be validated against Windows anyway.  The other changes may affect
code calling acpi_device_get_power() or acpi_device_update_power()
where ACPI_STATE_D3_HOT may be returned instead of ACPI_STATE_D3_COLD
(that's why the ACPI fan driver needs to be updated too) and since
transitions into ACPI_STATE_D3_HOT may remove power now, it is better
to avoid this one in acpi_pm_device_sleep_state() if the "no power
off" PM QoS flag is set.

The only existing user of acpi_device_can_poweroff() really cares
about the case when _PR3 is present, so the change in that function
should not cause any problems to happen too.

A plus is that PCI_D3hot can be mapped to ACPI_STATE_D3_HOT
now and the compatibility with older systems should be covered
automatically.

In any case, if any real problems result from this, it still will
be better to follow the Windows' behavior (which now is reflected
by the specification too) in general and handle the cases when it
doesn't work via quirks.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

In commit 5de21bb9 ("ACPI / PM: Drop CONFIG_PM_RUNTIME from the
ACPI core"), all occurrences of CONFIG_PM_RUNTIME were replaced with
CONFIG_PM. This created the following structure of #ifdef blocks in
the code:

 [...]
 #ifdef CONFIG_PM
 #ifdef CONFIG_PM
 /* always on / undead */
 #ifdef CONFIG_PM_SLEEP
 [...]
 #endif
 #endif
 [...]
 #endif

This patch removes the inner "#ifdef CONFIG_PM" block as it will
always be enabled when the outer block is enabled. This inconsistency
was found using the undertaker-checkpatch tool.
Signed-off-by: NAndreas Ruprecht <rupran@einserver.de>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

If an ACPI device object whose _STA returns 0 (not present and not
functional) has _PR0 or _PS0, its power_manageable flag will be set
and acpi_bus_init_power() will return 0 for it.  Consequently, if
such a device object is passed to the ACPI device PM functions, they
will attempt to carry out the requested operation on the device,
although they should not do that for devices that are not present.

To fix that problem make acpi_bus_init_power() return an error code
for devices that are not present which will cause power_manageable to
be cleared for them as appropriate in acpi_bus_get_power_flags().
However, the lists of power resources should not be freed for the
device in that case, so modify acpi_bus_get_power_flags() to keep
those lists even if acpi_bus_init_power() returns an error.
Accordingly, when deciding whether or not the lists of power
resources need to be freed, acpi_free_power_resources_lists()
should check the power.flags.power_resources flag instead of
flags.power_manageable, so make that change too.

Furthermore, if acpi_bus_attach() sees that flags.initialized is
unset for the given device, it should reset the power management
settings of the device and re-initialize them from scratch instead
of relying on the previous settings (the device may have appeared
after being not present previously, for example), so make it use
the 'valid' flag of the D0 power state as the initial value of
flags.power_manageable for it and call acpi_bus_init_power() to
discover its current power state.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Cc: 3.10+ <stable@vger.kernel.org> # 3.10+

In some cases acpi_device_wakeup() may be called to ensure wakeup
power to be off for a given device even though that device's wakeup
GPE has not been enabled so far.  It calls acpi_disable_gpe() on a
GPE that's not enabled and this causes ACPICA to return the AE_LIMIT
status code from that call which then is reported as an error by the
ACPICA's debug facilities (if enabled).  This may lead to a fair
amount of confusion, so introduce a new ACPI device wakeup flag
to store the wakeup GPE status and avoid disabling wakeup GPEs
that have not been enabled.
Reported-and-tested-by: NVenkat Raghavulu <venkat.raghavulu@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

After commit b2b49ccb (PM: Kconfig: Set PM_RUNTIME if PM_SLEEP is
selected) PM_RUNTIME is always set if PM is set, so quite a few
depend on CONFIG_PM.

Replace CONFIG_PM_RUNTIME with CONFIG_PM in the ACPI core code.
Reviewed-by: NUlf Hansson <ulf.hansson@linaro.org>
Acked-by: NKevin Hilman <khilman@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Signed-off-by: NHuang Rui <ray.huang@amd.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>