Transitioned power state logged at the end of setting ACPI power.
However, D3cold won't be in the message because state can only be
D3hot at most.
Use target_state to corretly report when power state is D3cold.
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tiger Lake's new unique ACPI device IDs for DPTF and fan drivers are not
valid as the IDs are missing 'C'. Fix the IDs by updating them.
After the update, the new IDs should now look like
INT1047 --> INTC1047
INT1040 --> INTC1040
INT1043 --> INTC1043
INT1044 --> INTC1044
Fixes: 55cfe6a5c5 ("ACPI: DPTF: Add Tiger Lake ACPI device IDs")
Fixes: c248dfe7e0 ("ACPI: fan: Add Tiger Lake ACPI device ID")
Suggested-by: Srinivas Pandruvada <srinivas.pandruvada@intel.com>
Signed-off-by: Gayatri Kammela <gayatri.kammela@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tiger Lake has a new unique ACPI device ID for the ACPI fan that
needs to be added to the fan driver and to the blacklist in
acpi_dev_pm_attach() to support it.
Signed-off-by: Gayatri Kammela <gayatri.kammela@intel.com>
[ rjw: Subject & changelog, fold in another patch ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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: e5cc8ef312 (ACPI / PM: Provide ACPI PM callback routines for subsystems)
Reported-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Todd Brandt <todd.e.brandt@linux.intel.com>
Cc: 3.10+ <stable@vger.kernel.org> # 3.10+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* pm-opp:
PM / OPP: Correct Documentation about library location
opp: of: Support multiple suspend OPPs defined in DT
dt-bindings: opp: Support multiple opp-suspend properties
opp: core: add regulators enable and disable
opp: Don't decrement uninitialized list_kref
* pm-qos:
PM: QoS: Get rid of unused flags
* acpi-pm:
ACPI: PM: Print debug messages on device power state changes
* pm-domains:
PM / Domains: Verify PM domain type in dev_pm_genpd_set_performance_state()
PM / Domains: Simplify genpd_lookup_dev()
PM / Domains: Align in-parameter names for some genpd functions
* pm-tools:
pm-graph: make setVal unbuffered again for python2 and python3
cpupower: update German translation
tools/power/cpupower: fix 64bit detection when cross-compiling
cpupower: Add missing newline at end of file
pm-graph v5.5
Add an ID and a device pointer to 'struct wakeup_source'. Use them to to
expose wakeup sources statistics in sysfs under
/sys/class/wakeup/wakeup<ID>/*.
Co-developed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Co-developed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Tri Vo <trong@android.com>
Tested-by: Kalesh Singh <kaleshsingh@google.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Add an acpi_handle_debug() statement to acpi_device_set_power() to
allow ACPI device power state changes to be tracked.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Commit f850a48a07 ("ACPI: PM: Allow transitions to D0 to occur in
special cases") overlooked the fact that acpi_power_transition() may
change the power.state value for the target device and if that
happens, it may confuse acpi_device_set_power() and cause it to
omit the _PS0 evaluation which on some systems is necessary to
change power states of devices from low-power to D0.
Fix that by saving the current value of power.state for the
target device before passing it to acpi_power_transition() and
using the saved value in a subsequent check.
Fixes: f850a48a07 ("ACPI: PM: Allow transitions to D0 to occur in special cases")
Reported-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Reported-by: Mario Limonciello <mario.limonciello@dell.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Tested-by: Mario Limonciello <mario.limonciello@dell.com>
* pm-sleep:
PM: sleep: Drop dev_pm_skip_next_resume_phases()
ACPI: PM: Drop unused function and function header
ACPI: PM: Introduce "poweroff" callbacks for ACPI PM domain and LPSS
ACPI: PM: Simplify and fix PM domain hibernation callbacks
PCI: PM: Simplify bus-level hibernation callbacks
PM: ACPI/PCI: Resume all devices during hibernation
kernel: power: swap: use kzalloc() instead of kmalloc() followed by memset()
PM: sleep: Update struct wakeup_source documentation
drivers: base: power: remove wakeup_sources_stats_dentry variable
PM: suspend: Rename pm_suspend_via_s2idle()
PM: sleep: Show how long dpm_suspend_start() and dpm_suspend_end() take
PM: hibernate: powerpc: Expose pfn_is_nosave() prototype
* acpi-pm:
ACPI: PM: Make acpi_sleep_state_supported() non-static
ACPI: PM: Allow transitions to D0 to occur in special cases
ACPI: PM: Avoid evaluating _PS3 on transitions from D3hot to D3cold
ACPI / sleep: Switch to use acpi_dev_get_first_match_dev()
ACPI / LPIT: Correct LPIT end address for lpit_process()
* pm-pci:
ACPI: PM: Unexport acpi_device_get_power()
PCI: PM/ACPI: Refresh all stale power state data in pci_pm_complete()
PCI / ACPI: Add _PR0 dependent devices
ACPI / PM: Introduce concept of a _PR0 dependent device
PCI / ACPI: Use cached ACPI device state to get PCI device power state
PCI: Do not poll for PME if the device is in D3cold
PCI: Add missing link delays required by the PCIe spec
PCI: PM: Replace pci_dev_keep_suspended() with two functions
PCI: PM: Avoid resuming devices in D3hot during system suspend
Using acpi_device_get_power() outside of ACPI device initialization
and ACPI sysfs is problematic due to the way in which power resources
are handled by it, so unexport it and add a paragraph explaining the
pitfalls to its kerneldoc comment.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
In general, it is not correct to call pm_generic_suspend(),
pm_generic_suspend_late() and pm_generic_suspend_noirq() during the
hibernation's "poweroff" transition, because device drivers may
provide special callbacks to be invoked then and the wrappers in
question cause system suspend callbacks to be run. Unfortunately,
that happens in the ACPI PM domain and ACPI LPSS.
To address this potential issue, introduce "poweroff" callbacks
for the ACPI PM and LPSS that will use pm_generic_poweroff(),
pm_generic_poweroff_late() and pm_generic_poweroff_noirq() as
appropriate.
Fixes: 05087360fd (ACPI / PM: Take SMART_SUSPEND driver flag into account)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
First, after a previous change causing all runtime-suspended devices
in the ACPI PM domain (and ACPI LPSS devices) to be resumed before
creating a snapshot image of memory during hibernation, it is not
necessary to worry about the case in which them might be left in
runtime-suspend any more, so get rid of the code related to that from
ACPI PM domain and ACPI LPSS hibernation callbacks.
Second, it is not correct to use pm_generic_resume_early() and
acpi_subsys_resume_noirq() in hibernation "restore" callbacks (which
currently happens in the ACPI PM domain and ACPI LPSS), so introduce
proper _restore_late and _restore_noirq callbacks for the ACPI PM
domain and ACPI LPSS.
Fixes: 05087360fd (ACPI / PM: Take SMART_SUSPEND driver flag into account)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Both the PCI bus type and the ACPI PM domain avoid resuming
runtime-suspended devices with DPM_FLAG_SMART_SUSPEND set during
hibernation (before creating the snapshot image of system memory),
but that turns out to be a mistake. It leads to functional issues
and adds complexity that's hard to justify.
For this reason, resume all runtime-suspended PCI devices and all
devices in the ACPI PM domains before creating a snapshot image of
system memory during hibernation.
Fixes: 05087360fd (ACPI / PM: Take SMART_SUSPEND driver flag into account)
Fixes: c4b65157ae (PCI / PM: Take SMART_SUSPEND driver flag into account)
Link: https://lore.kernel.org/linux-acpi/917d4399-2e22-67b1-9d54-808561f9083f@uwyo.edu/T/#maf065fe6e4974f2a9d79f332ab99dfaba635f64c
Reported-by: Robert R. Howell <RHowell@uwyo.edu>
Tested-by: Robert R. Howell <RHowell@uwyo.edu>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
If a device with ACPI PM is left in D0 during a system-wide
transition to the S3 (suspend-to-RAM) or S4 (hibernation) sleep
state, the actual state of the device need not be D0 during resume
from it, although its power.state value will still reflect D0 (that
is, the power state from before the system-wide transition).
In that case, the acpi_device_set_power() call made to ensure that
the power state of the device will be D0 going forward has no effect,
because the new state (D0) is equal to the one reflected by the
device's power.state value. That does not affect power resources,
which are taken care of by acpi_resume_power_resources() called from
acpi_pm_finish() during resume from system-wide sleep states, but it
still may be necessary to invoke _PS0 for the device on top of that
in order to finalize its transition to D0.
For this reason, modify acpi_device_set_power() to allow transitions
to D0 to occur even if D0 is the current power state of the device
according to its power.state value.
That will not affect power resources, which are assumed to be in
the right configuration already (as reflected by the current values
of their reference counters), but it may cause _PS0 to be evaluated
for the device. However, evaluating _PS0 for a device already in D0
may lead to confusion in general, so invoke _PSC (if present) to
check the device's current power state upfront and only evaluate
_PS0 for it if _PSC has returned a power state different from D0.
[If _PSC is not present or the evaluation of it fails, the power
state of the device is assumed to be D0 at this point.]
Fixes: 20dacb71ad (ACPI / PM: Rework device power management to follow ACPI 6)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
If the power state of a device with ACPI PM is changed from D3hot to
D3cold, it merely is a matter of dropping references to additional
power resources (specifically, those in the list returned by _PR3),
and the _PS3 method should not be invoked for the device then (as
it has already been evaluated during the previous transition to
D3hot).
Fixes: 20dacb71ad (ACPI / PM: Rework device power management to follow ACPI 6)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
- Modify the PCI bus type's PM code to avoid putting devices left
by their drivers in D0 on purpose during suspend to idle into
low-power states as doing that may confuse the system resume
callbacks of the drivers in question (Rafael Wysocki).
- Avoid checking ACPI wakeup configuration during system-wide
suspend for suspended devices that do not use ACPI-based wakeup
to allow them to stay in suspend more often (Rafael Wysocki).
- The last phase of hibernation is analogous to system-wide suspend
also because on platforms with ACPI it passes control to the
platform firmware to complete the transision, so make it indicate
that by calling pm_set_suspend_via_firmware() to allow the drivers
that care about this to do the right thing (Rafael Wysocki).
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Merge tag 'pm-5.2-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fixes from Rafael Wysocki:
"These fix three issues in the system-wide suspend and hibernation area
related to PCI device PM handling by suspend-to-idle, device wakeup
optimizations and arbitrary differences between suspend and
hiberantion.
Specifics:
- Modify the PCI bus type's PM code to avoid putting devices left by
their drivers in D0 on purpose during suspend to idle into
low-power states as doing that may confuse the system resume
callbacks of the drivers in question (Rafael Wysocki).
- Avoid checking ACPI wakeup configuration during system-wide suspend
for suspended devices that do not use ACPI-based wakeup to allow
them to stay in suspend more often (Rafael Wysocki).
- The last phase of hibernation is analogous to system-wide suspend
also because on platforms with ACPI it passes control to the
platform firmware to complete the transision, so make it indicate
that by calling pm_set_suspend_via_firmware() to allow the drivers
that care about this to do the right thing (Rafael Wysocki)"
* tag 'pm-5.2-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PCI: PM: Avoid possible suspend-to-idle issue
ACPI: PM: Call pm_set_suspend_via_firmware() during hibernation
ACPI/PCI: PM: Add missing wakeup.flags.valid checks
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation this program is
distributed in the hope that it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 655 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070034.575739538@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
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Merge tag 'printk-for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk
Pull printk updates from Petr Mladek:
- Allow state reset of printk_once() calls.
- Prevent crashes when dereferencing invalid pointers in vsprintf().
Only the first byte is checked for simplicity.
- Make vsprintf warnings consistent and inlined.
- Treewide conversion of obsolete %pf, %pF to %ps, %pF printf
modifiers.
- Some clean up of vsprintf and test_printf code.
* tag 'printk-for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk:
lib/vsprintf: Make function pointer_string static
vsprintf: Limit the length of inlined error messages
vsprintf: Avoid confusion between invalid address and value
vsprintf: Prevent crash when dereferencing invalid pointers
vsprintf: Consolidate handling of unknown pointer specifiers
vsprintf: Factor out %pO handler as kobject_string()
vsprintf: Factor out %pV handler as va_format()
vsprintf: Factor out %p[iI] handler as ip_addr_string()
vsprintf: Do not check address of well-known strings
vsprintf: Consistent %pK handling for kptr_restrict == 0
vsprintf: Shuffle restricted_pointer()
printk: Tie printk_once / printk_deferred_once into .data.once for reset
treewide: Switch printk users from %pf and %pF to %ps and %pS, respectively
lib/test_printf: Switch to bitmap_zalloc()
In sufficiently complicated GPE configurations it is hard to
determine which GPE could be the source of system wakeup from a sleep
state, so make __acpi_device_wakeup_enable() print that information
to the kernel log if debugging is enabled.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Export acpi_device_get_power() for use by modular build drivers.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
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: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael 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: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael 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: Daniel Drake <drake@endlessm.com>
Link: http://lkml.kernel.org/r/CAB4CAwf_k-WsF3zL4epm9TKAOu0h=Bv1XhXV_gY3bziOo_NPKA@mail.gmail.comhttps://phabricator.endlessm.com/T21410
Signed-off-by: Rafael 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: c4b65157ae (PCI / PM: Take SMART_SUSPEND driver flag into account)
Fixes: 05087360fd (ACPI / PM: Take SMART_SUSPEND driver flag into account)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Bjorn 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: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* pm-core:
ACPI / PM: Take SMART_SUSPEND driver flag into account
PCI / PM: Take SMART_SUSPEND driver flag into account
PCI / PM: Drop unnecessary invocations of pcibios_pm_ops callbacks
PM / core: Add SMART_SUSPEND driver flag
PCI / PM: Use the NEVER_SKIP driver flag
PM / core: Add NEVER_SKIP and SMART_PREPARE driver flags
PM / core: Convert timers to use timer_setup()
PM / core: Fix kerneldoc comments of four functions
PM / core: Drop legacy class suspend/resume operations
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 a1d14934ea "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-ga1d14934ea4b #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: c072530f39 (ACPI / PM: Revork the handling of ACPI device wakeup notifications)
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: 3.17+ <stable@vger.kernel.org> # 3.17+
Signed-off-by: Rafael 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: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg 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: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Ulf 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: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf 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: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Mika 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: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Commit 58a1fbbb2e (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 58a1fbbb2e (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: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael 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: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf 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: Rafael 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: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Bjorn 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: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
- Rearrange the core device properties code by moving the code
specific to each supported platform configuration framework
(ACPI, DT and build-in) into a separate file (Sakari Ailus).
- Add helper functions for accessing device properties in a
firmware-agnostic way (Sakari Ailus, Kieran Bingham).
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Merge tag 'devprop-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull device properties framework updates from Rafael Wysocki:
"These mostly rearrange the device properties core code and add a few
helper functions to it as a foundation for future work.
Specifics:
- Rearrange the core device properties code by moving the code
specific to each supported platform configuration framework (ACPI,
DT and build-in) into a separate file (Sakari Ailus).
- Add helper functions for accessing device properties in a
firmware-agnostic way (Sakari Ailus, Kieran Bingham)"
* tag 'devprop-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
device property: Add fwnode_graph_get_port_parent
device property: Add FW type agnostic fwnode_graph_get_remote_node
device property: Introduce fwnode_device_is_available()
device property: Move fwnode graph ops to firmware specific locations
device property: Move FW type specific functionality to FW specific files
ACPI: Constify argument to acpi_device_is_present()
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: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Bjorn 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: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Bjorn 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: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael 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: Rafael 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: Rafael 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: Rafael 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: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
