Merge tag 'pm+acpi-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI and power management updates from Rafael Wysocki:
 "The majority of this material spent some time in linux-next, some of
  it even several weeks.  There are a few relatively fresh commits in
  it, but they are mostly fixes and simple cleanups.

  ACPI took the lead this time, both in terms of the number of commits
  and the number of modified lines of code, cpufreq follows and there
  are a few changes in the PM core and in cpuidle too.

  A new feature that already got some LWN.net's attention is the device
  PM QoS extension allowing latency tolerance requirements to be
  propagated from leaf devices to their ancestors with hardware
  interfaces for specifying latency tolerance.  That should help systems
  with hardware-driven power management to avoid going too far with it
  in cases when there are latency tolerance constraints.

  There also are some significant changes in the ACPI core related to
  the way in which hotplug notifications are handled.  They affect PCI
  hotplug (ACPIPHP) and the ACPI dock station code too.  The bottom line
  is that all those notification now go through the root notify handler
  and are propagated to the interested subsystems by means of callbacks
  instead of having to install a notify handler for each device object
  that we can potentially get hotplug notifications for.

  In addition to that ACPICA will now advertise "Windows 2013"
  compatibility for _OSI, because some systems out there don't work
  correctly if that is not done (some of them don't even boot).

  On the system suspend side of things, all of the device suspend and
  resume callbacks, except for ->prepare() and ->complete(), are now
  going to be executed asynchronously as that turns out to speed up
  system suspend and resume on some platforms quite significantly and we
  have a few more optimizations in that area.

  Apart from that, there are some new device IDs and fixes and cleanups
  all over.  In particular, the system suspend and resume handling by
  cpufreq should be improved and the cpuidle menu governor should be a
  bit more robust now.

  Specifics:

   - Device PM QoS support for latency tolerance constraints on systems
     with hardware interfaces allowing such constraints to be specified.
     That is necessary to prevent hardware-driven power management from
     becoming overly aggressive on some systems and to prevent power
     management features leading to excessive latencies from being used
     in some cases.

   - Consolidation of the handling of ACPI hotplug notifications for
     device objects.  This causes all device hotplug notifications to go
     through the root notify handler (that was executed for all of them
     anyway before) that propagates them to individual subsystems, if
     necessary, by executing callbacks provided by those subsystems
     (those callbacks are associated with struct acpi_device objects
     during device enumeration).  As a result, the code in question
     becomes both smaller in size and more straightforward and all of
     those changes should not affect users.

   - ACPICA update, including fixes related to the handling of _PRT in
     cases when it is broken and the addition of "Windows 2013" to the
     list of supported "features" for _OSI (which is necessary to
     support systems that work incorrectly or don't even boot without
     it).  Changes from Bob Moore and Lv Zheng.

   - Consolidation of ACPI _OST handling from Jiang Liu.

   - ACPI battery and AC fixes allowing unusual system configurations to
     be handled by that code from Alexander Mezin.

   - New device IDs for the ACPI LPSS driver from Chiau Ee Chew.

   - ACPI fan and thermal optimizations related to system suspend and
     resume from Aaron Lu.

   - Cleanups related to ACPI video from Jean Delvare.

   - Assorted ACPI fixes and cleanups from Al Stone, Hanjun Guo, Lan
     Tianyu, Paul Bolle, Tomasz Nowicki.

   - Intel RAPL (Running Average Power Limits) driver cleanups from
     Jacob Pan.

   - intel_pstate fixes and cleanups from Dirk Brandewie.

   - cpufreq fixes related to system suspend/resume handling from Viresh
     Kumar.

   - cpufreq core fixes and cleanups from Viresh Kumar, Stratos
     Karafotis, Saravana Kannan, Rashika Kheria, Joe Perches.

   - cpufreq drivers updates from Viresh Kumar, Zhuoyu Zhang, Rob
     Herring.

   - cpuidle fixes related to the menu governor from Tuukka Tikkanen.

   - cpuidle fix related to coupled CPUs handling from Paul Burton.

   - Asynchronous execution of all device suspend and resume callbacks,
     except for ->prepare and ->complete, during system suspend and
     resume from Chuansheng Liu.

   - Delayed resuming of runtime-suspended devices during system suspend
     for the PCI bus type and ACPI PM domain.

   - New set of PM helper routines to allow device runtime PM callbacks
     to be used during system suspend and resume more easily from Ulf
     Hansson.

   - Assorted fixes and cleanups in the PM core from Geert Uytterhoeven,
     Prabhakar Lad, Philipp Zabel, Rashika Kheria, Sebastian Capella.

   - devfreq fix from Saravana Kannan"

* tag 'pm+acpi-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (162 commits)
  PM / devfreq: Rewrite devfreq_update_status() to fix multiple bugs
  PM / sleep: Correct whitespace errors in <linux/pm.h>
  intel_pstate: Set core to min P state during core offline
  cpufreq: Add stop CPU callback to cpufreq_driver interface
  cpufreq: Remove unnecessary braces
  cpufreq: Fix checkpatch errors and warnings
  cpufreq: powerpc: add cpufreq transition latency for FSL e500mc SoCs
  MAINTAINERS: Reorder maintainer addresses for PM and ACPI
  PM / Runtime: Update runtime_idle() documentation for return value meaning
  video / output: Drop display output class support
  fujitsu-laptop: Drop unneeded include
  acer-wmi: Stop selecting VIDEO_OUTPUT_CONTROL
  ACPI / gpu / drm: Stop selecting VIDEO_OUTPUT_CONTROL
  ACPI / video: fix ACPI_VIDEO dependencies
  cpufreq: remove unused notifier: CPUFREQ_{SUSPENDCHANGE|RESUMECHANGE}
  cpufreq: Do not allow ->setpolicy drivers to provide ->target
  cpufreq: arm_big_little: set 'physical_cluster' for each CPU
  cpufreq: arm_big_little: make vexpress driver depend on bL core driver
  ACPI / button: Add ACPI Button event via netlink routine
  ACPI: Remove duplicate definitions of PREFIX
  ...

7 files changed, 105 insertions, 31 deletions

diff --git a/Documentation/ABI/testing/sysfs-devices-power b/Documentation/ABI/testing/sysfs-devices-power
index efe449bdf811..7dbf96b724ed 100644
--- a/Documentation/ABI/testing/sysfs-devices-power
+++ b/Documentation/ABI/testing/sysfs-devices-power
@@ -187,7 +187,7 @@ Description:
 		Not all drivers support this attribute.  If it isn't supported,
 		attempts to read or write it will yield I/O errors.
 
-What:		/sys/devices/.../power/pm_qos_latency_us
+What:		/sys/devices/.../power/pm_qos_resume_latency_us
 Date:		March 2012
 Contact:	Rafael J. Wysocki <rjw@rjwysocki.net>
 Description:
@@ -205,6 +205,31 @@ Description:
 		This attribute has no effect on system-wide suspend/resume and
 		hibernation.
 
+What:		/sys/devices/.../power/pm_qos_latency_tolerance_us
+Date:		January 2014
+Contact:	Rafael J. Wysocki <rjw@rjwysocki.net>
+Description:
+		The /sys/devices/.../power/pm_qos_latency_tolerance_us attribute
+		contains the PM QoS active state latency tolerance limit for the
+		given device in microseconds.  That is the maximum memory access
+		latency the device can suffer without any visible adverse
+		effects on user space functionality.  If that value is the
+		string "any", the latency does not matter to user space at all,
+		but hardware should not be allowed to set the latency tolerance
+		for the device automatically.
+
+		Reading "auto" from this file means that the maximum memory
+		access latency for the device may be determined automatically
+		by the hardware as needed.  Writing "auto" to it allows the
+		hardware to be switched to this mode if there are no other
+		latency tolerance requirements from the kernel side.
+
+		This attribute is only present if the feature controlled by it
+		is supported by the hardware.
+
+		This attribute has no effect on runtime suspend and resume of
+		devices and on system-wide suspend/resume and hibernation.
+
 What:		/sys/devices/.../power/pm_qos_no_power_off
 Date:		September 2012
 Contact:	Rafael J. Wysocki <rjw@rjwysocki.net>
diff --git a/Documentation/ABI/testing/sysfs-power b/Documentation/ABI/testing/sysfs-power
index 205a73878441..64c9276e9421 100644
--- a/Documentation/ABI/testing/sysfs-power
+++ b/Documentation/ABI/testing/sysfs-power
@@ -12,8 +12,9 @@ Contact:	Rafael J. Wysocki <rjw@rjwysocki.net>
 Description:
 		The /sys/power/state file controls the system power state.
 		Reading from this file returns what states are supported,
-		which is hard-coded to 'standby' (Power-On Suspend), 'mem'
-		(Suspend-to-RAM), and 'disk' (Suspend-to-Disk).
+		which is hard-coded to 'freeze' (Low-Power Idle), 'standby'
+		(Power-On Suspend), 'mem' (Suspend-to-RAM), and 'disk'
+		(Suspend-to-Disk).
 
 		Writing to this file one of these strings causes the system to
 		transition into that state. Please see the file
diff --git a/Documentation/cpu-freq/core.txt b/Documentation/cpu-freq/core.txt
index ce0666e51036..0060d76b445f 100644
--- a/Documentation/cpu-freq/core.txt
+++ b/Documentation/cpu-freq/core.txt
@@ -92,7 +92,3 @@ values:
 cpu	- number of the affected CPU
 old	- old frequency
 new	- new frequency
-
-If the cpufreq core detects the frequency has changed while the system
-was suspended, these notifiers are called with CPUFREQ_RESUMECHANGE as
-second argument.
diff --git a/Documentation/cpu-freq/cpu-drivers.txt b/Documentation/cpu-freq/cpu-drivers.txt
index 8b1a4451422e..48da5fdcb9f1 100644
--- a/Documentation/cpu-freq/cpu-drivers.txt
+++ b/Documentation/cpu-freq/cpu-drivers.txt
@@ -61,7 +61,13 @@ target_index		-	See below on the differences.
 
 And optionally
 
-cpufreq_driver.exit -		A pointer to a per-CPU cleanup function.
+cpufreq_driver.exit -		A pointer to a per-CPU cleanup
+				function called during CPU_POST_DEAD
+				phase of cpu hotplug process.
+
+cpufreq_driver.stop_cpu -	A pointer to a per-CPU stop function
+				called during CPU_DOWN_PREPARE phase of
+				cpu hotplug process.
 
 cpufreq_driver.resume -		A pointer to a per-CPU resume function
 				which is called with interrupts disabled
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 67755ea834a7..121d5fcbd94a 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -231,6 +231,14 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 
 	acpi_no_auto_ssdt	[HW,ACPI] Disable automatic loading of SSDT
 
+	acpica_no_return_repair [HW, ACPI]
+			Disable AML predefined validation mechanism
+			This mechanism can repair the evaluation result to make
+			the return objects more ACPI specification compliant.
+			This option is useful for developers to identify the
+			root cause of an AML interpreter issue when the issue
+			has something to do with the repair mechanism.
+
 	acpi_os_name=	[HW,ACPI] Tell ACPI BIOS the name of the OS
 			Format: To spoof as Windows 98: ="Microsoft Windows"
 
diff --git a/Documentation/power/pm_qos_interface.txt b/Documentation/power/pm_qos_interface.txt
index 483632087788..a5da5c7e7128 100644
--- a/Documentation/power/pm_qos_interface.txt
+++ b/Documentation/power/pm_qos_interface.txt
@@ -88,17 +88,19 @@ node.
 
 2. PM QoS per-device latency and flags framework
 
-For each device, there are two lists of PM QoS requests. One is maintained
-along with the aggregated target of latency value and the other is for PM QoS
-flags. Values are updated in response to changes of the request list.
+For each device, there are three lists of PM QoS requests. Two of them are
+maintained along with the aggregated targets of resume latency and active
+state latency tolerance (in microseconds) and the third one is for PM QoS flags.
+Values are updated in response to changes of the request list.
 
-Target latency value is simply the minimum of the request values held in the
-parameter list elements.  The PM QoS flags aggregate value is a gather (bitwise
-OR) of all list elements' values. Two device PM QoS flags are defined currently:
-PM_QOS_FLAG_NO_POWER_OFF and PM_QOS_FLAG_REMOTE_WAKEUP.
+The target values of resume latency and active state latency tolerance are
+simply the minimum of the request values held in the parameter list elements.
+The PM QoS flags aggregate value is a gather (bitwise OR) of all list elements'
+values.  Two device PM QoS flags are defined currently: PM_QOS_FLAG_NO_POWER_OFF
+and PM_QOS_FLAG_REMOTE_WAKEUP.
 
-Note: the aggregated target value is implemented as an atomic variable so that
-reading the aggregated value does not require any locking mechanism.
+Note: The aggregated target values are implemented in such a way that reading
+the aggregated value does not require any locking mechanism.
 
 
 From kernel mode the use of this interface is the following:
@@ -132,19 +134,21 @@ The meaning of the return values is as follows:
 	PM_QOS_FLAGS_UNDEFINED: The device's PM QoS structure has not been
 			initialized or the list of requests is empty.
 
-int dev_pm_qos_add_ancestor_request(dev, handle, value)
+int dev_pm_qos_add_ancestor_request(dev, handle, type, value)
 Add a PM QoS request for the first direct ancestor of the given device whose
-power.ignore_children flag is unset.
+power.ignore_children flag is unset (for DEV_PM_QOS_RESUME_LATENCY requests)
+or whose power.set_latency_tolerance callback pointer is not NULL (for
+DEV_PM_QOS_LATENCY_TOLERANCE requests).
 
 int dev_pm_qos_expose_latency_limit(device, value)
-Add a request to the device's PM QoS list of latency constraints and create
-a sysfs attribute pm_qos_resume_latency_us under the device's power directory
-allowing user space to manipulate that request.
+Add a request to the device's PM QoS list of resume latency constraints and
+create a sysfs attribute pm_qos_resume_latency_us under the device's power
+directory allowing user space to manipulate that request.
 
 void dev_pm_qos_hide_latency_limit(device)
 Drop the request added by dev_pm_qos_expose_latency_limit() from the device's
-PM QoS list of latency constraints and remove sysfs attribute pm_qos_resume_latency_us
-from the device's power directory.
+PM QoS list of resume latency constraints and remove sysfs attribute
+pm_qos_resume_latency_us from the device's power directory.
 
 int dev_pm_qos_expose_flags(device, value)
 Add a request to the device's PM QoS list of flags and create sysfs attributes
@@ -163,7 +167,7 @@ a per-device notification tree and a global notification tree.
 int dev_pm_qos_add_notifier(device, notifier):
 Adds a notification callback function for the device.
 The callback is called when the aggregated value of the device constraints list
-is changed.
+is changed (for resume latency device PM QoS only).
 
 int dev_pm_qos_remove_notifier(device, notifier):
 Removes the notification callback function for the device.
@@ -171,14 +175,48 @@ Removes the notification callback function for the device.
 int dev_pm_qos_add_global_notifier(notifier):
 Adds a notification callback function in the global notification tree of the
 framework.
-The callback is called when the aggregated value for any device is changed.
+The callback is called when the aggregated value for any device is changed
+(for resume latency device PM QoS only).
 
 int dev_pm_qos_remove_global_notifier(notifier):
 Removes the notification callback function from the global notification tree
 of the framework.
 
 
-From user mode:
-No API for user space access to the per-device latency constraints is provided
-yet - still under discussion.
-
+Active state latency tolerance
+
+This device PM QoS type is used to support systems in which hardware may switch
+to energy-saving operation modes on the fly.  In those systems, if the operation
+mode chosen by the hardware attempts to save energy in an overly aggressive way,
+it may cause excess latencies to be visible to software, causing it to miss
+certain protocol requirements or target frame or sample rates etc.
+
+If there is a latency tolerance control mechanism for a given device available
+to software, the .set_latency_tolerance callback in that device's dev_pm_info
+structure should be populated.  The routine pointed to by it is should implement
+whatever is necessary to transfer the effective requirement value to the
+hardware.
+
+Whenever the effective latency tolerance changes for the device, its
+.set_latency_tolerance() callback will be executed and the effective value will
+be passed to it.  If that value is negative, which means that the list of
+latency tolerance requirements for the device is empty, the callback is expected
+to switch the underlying hardware latency tolerance control mechanism to an
+autonomous mode if available.  If that value is PM_QOS_LATENCY_ANY, in turn, and
+the hardware supports a special "no requirement" setting, the callback is
+expected to use it.  That allows software to prevent the hardware from
+automatically updating the device's latency tolerance in response to its power
+state changes (e.g. during transitions from D3cold to D0), which generally may
+be done in the autonomous latency tolerance control mode.
+
+If .set_latency_tolerance() is present for the device, sysfs attribute
+pm_qos_latency_tolerance_us will be present in the devivce's power directory.
+Then, user space can use that attribute to specify its latency tolerance
+requirement for the device, if any.  Writing "any" to it means "no requirement,
+but do not let the hardware control latency tolerance" and writing "auto" to it
+allows the hardware to be switched to the autonomous mode if there are no other
+requirements from the kernel side in the device's list.
+
+Kernel code can use the functions described above along with the
+DEV_PM_QOS_LATENCY_TOLERANCE device PM QoS type to add, remove and update
+latency tolerance requirements for devices.
diff --git a/Documentation/trace/events-power.txt b/Documentation/trace/events-power.txt
index 3bd33b8dc7c4..21d514ced212 100644
--- a/Documentation/trace/events-power.txt
+++ b/Documentation/trace/events-power.txt
@@ -92,5 +92,5 @@ dev_pm_qos_remove_request          "device=%s type=%s new_value=%d"
 
 The first parameter gives the device name which tries to add/update/remove
 QoS requests.
-The second parameter gives the request type (e.g. "DEV_PM_QOS_LATENCY").
+The second parameter gives the request type (e.g. "DEV_PM_QOS_RESUME_LATENCY").
 The third parameter is value to be added/updated/removed.