ACPI / battery: Fix parsing _BIX return value

The _BIX method returns extended battery info as a package.
According the ACPI spec (ACPI 5, Section 10.2.2.2), the first member
of that package should be "Revision".  However, the current ACPI
battery driver treats the first member as "Power Unit" which should
be the second member.  This causes the result of _BIX return data
parsing to be incorrect.

Fix this by adding a new member called 'revision' to struct
acpi_battery and adding the offsetof() information on it to
extended_info_offsets[] as the first row.

[rjw: Changelog]
Reported-and-tested-by: Jan Hoffmann <jan.christian.hoffmann@gmail.com>
References: http://bugzilla.kernel.org/show_bug.cgi?id=60519
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Cc: 2.6.34+ <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
freezer: set PF_SUSPEND_TASK flag on tasks that call freeze_processes

Calling freeze_processes sets a global flag that will cause any
process that calls try_to_freeze to enter the refrigerator.  It
skips sending a signal to the current task, but if the current
task ever hits try_to_freeze, all threads will be frozen and the
system will deadlock.

Set a new flag, PF_SUSPEND_TASK, on the task that calls
freeze_processes.  The flag notifies the freezer that the thread
is involved in suspend and should not be frozen.  Also add a
WARN_ON in thaw_processes if the caller does not have the
PF_SUSPEND_TASK flag set to catch if a different task calls
thaw_processes than the one that called freeze_processes, leaving
a task with PF_SUSPEND_TASK permanently set on it.

Threads that spawn off a task with PF_SUSPEND_TASK set (which
swsusp does) will also have PF_SUSPEND_TASK set, preventing them
from freezing while they are helping with suspend, but they need
to be dead by the time suspend is triggered, otherwise they may
run when userspace is expected to be frozen.  Add a WARN_ON in
thaw_processes if more than one thread has the PF_SUSPEND_TASK
flag set.

Reported-and-tested-by: Michael Leun <lkml20130126@newton.leun.net>
Signed-off-by: Colin Cross <ccross@android.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Merge branch 'fixes-next' into pm-cpufreq-next
cpufreq: Fix misplaced call to cpufreq_update_policy()

The call to cpufreq_update_policy() is placed in the CPU hotplug callback
of cpufreq_stats, which has a higher priority than the CPU hotplug callback
of cpufreq-core. As a result, during CPU_ONLINE/CPU_ONLINE_FROZEN, we end up
calling cpufreq_update_policy() *before* calling cpufreq_add_dev() !
And for uninitialized CPUs, it just returns silently, not doing anything.

To add to that, cpufreq_stats is not even the right place to call
cpufreq_update_policy() to begin with. The cpufreq core ought to handle
this in its own callback, from an elegance/relevance perspective.

So move the invocation of cpufreq_update_policy() to cpufreq_cpu_callback,
and place it *after* cpufreq_add_dev().

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq: Add helper to perform alloc/free of policy structure

Separate out the allocation of the cpufreq policy structure (along with
its error handling) to a helper function. This makes the code easier to
read and also helps with some upcoming code reorganization.

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq: Extract non-interface related stuff from cpufreq_add_dev_interface

cpufreq_add_dev_interface() includes the work of exposing the interface
to the device, as well as a lot of unrelated stuff. Move the latter to
cpufreq_add_dev(), where it is more appropriate.

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq: Extract the handover of policy cpu to a helper function

During cpu offline, when the policy->cpu is going down, some other CPU
present in the policy->cpus mask is nominated as the new policy->cpu.
Extract this functionality from __cpufreq_remove_dev() and implement
it in a helper function. This helps in upcoming code reorganization.

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq: Introduce a flag ('frozen') to separate full vs temporary init/teardown

During suspend/resume we would like to do a light-weight init/teardown of
CPUs in the cpufreq subsystem and preserve certain things such as sysfs files
etc across suspend/resume transitions. Add a flag called 'frozen' to help
distinguish the full init/teardown sequence from the light-weight one.

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq: Preserve policy structure across suspend/resume

To perform light-weight cpu-init and teardown in the cpufreq subsystem
during suspend/resume, we need to separate out the 2 main functionalities
of the cpufreq CPU hotplug callbacks, as outlined below:

1. Init/tear-down of core cpufreq and CPU-specific components, which are
   critical to the correct functioning of the cpufreq subsystem.

2. Init/tear-down of cpufreq sysfs files during suspend/resume.

The first part requires accurate updates to the policy structure such as
its ->cpus and ->related_cpus masks, whereas the second part requires that
the policy->kobj structure is not released or re-initialized during
suspend/resume.

To handle both these requirements, we need to allow updates to the policy
structure throughout suspend/resume, but prevent the structure from getting
freed up. Also, we must have a mechanism by which the cpu-up callbacks can
restore the policy structure, without allocating things afresh. (That also
helps avoid memory leaks).

To achieve this, we use 2 schemes:
a. Use a fallback per-cpu storage area for preserving the policy structures
   during suspend, so that they can be restored during resume appropriately.

b. Use the 'frozen' flag to determine when to free or allocate the policy
   structure vs when to restore the policy from the saved fallback storage.
   Thus we can successfully preserve the structure across suspend/resume.

Effectively, this helps us complete the separation of the 'light-weight'
and the 'full' init/tear-down sequences in the cpufreq subsystem, so that
this can be made use of in the suspend/resume scenario.

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq: Perform light-weight init/teardown during suspend/resume

Now that we have the infrastructure to perform a light-weight init/tear-down,
use that in the cpufreq CPU hotplug notifier when invoked from the
suspend/resume path.

This also ensures that the file permissions of the cpufreq sysfs files are
preserved across suspend/resume, something which commit a66b2e (cpufreq:
Preserve sysfs files across suspend/resume) originally intended to do, but
had to be reverted due to other problems.

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI / PM: Only set power states of devices that are power manageable

Make acpi_device_set_power() check if the given device is power
manageable before checking if the given power state is valid for that
device.  Otherwise it will print that "Device does not support" that
power state into the kernel log, which may not make sense for some
power states (D0 and D3cold are supported by all devices by
definition).

Tested-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI / PM: Make messages in acpi_device_set_power() print device names

Modify acpi_device_set_power() so that diagnostic messages printed by
it to the kernel log always contain the name of the device concerned
to make it possible to identify the device that triggered the message
if need be.

Also replace printk(KERN_WARNING ) with dev_warn() everywhere in that
function.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com>
ACPI / PM: Use ACPI_STATE_D3_COLD instead of ACPI_STATE_D3 everywhere

There are several places in the tree where ACPI_STATE_D3 is used
instead of ACPI_STATE_D3_COLD which should be used instead for
clarity.  Modify them all to use ACPI_STATE_D3_COLD as appropriate.

[The definition of ACPI_STATE_D3 itself cannot go away at this point
 as it is part of ACPICA.]

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com>
ACPI: Move acpi_bus_get_device() from bus.c to scan.c

Move acpi_bus_get_device() from bus.c to scan.c which allows
acpi_bus_data_handler() to become static and clean up the latter.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI: blacklist win8 OSI for ASUS Zenbok Prime UX31A

Since v3.7 the ACPI backlight driver doesn't work at all on this
machine, because presumably the backlight AML code in the ACPI
tables contains a code path that triggers when the OS identifies
itself as compatible with Windows 8 (which the kernel started to
do in 3.7).  That code path is never used by Windows and on this
particular machine it turns out to be unusable at all.

Work around this problem by blacklisting the win8 OSI, so we are back
to v3.6 behavior (that is, we don't tell the BIOS that we are
compatible with Windows 8).

Since v3.7, users have been forced to work around the initial
regression by modifying the boot arguments [1].

[1] https://wiki.archlinux.org/index.php/ASUS_Zenbook_Prime_UX31A

[rjw: Changelog]
Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Merge branch 'fixes-next' into linux-next

* fixes-next:
  freezer: set PF_SUSPEND_TASK flag on tasks that call freeze_processes
  ACPI / battery: Fix parsing _BIX return value
Merge branch 'pm-cpufreq-next' into linux-next

* pm-cpufreq-next:
  cpufreq: Perform light-weight init/teardown during suspend/resume
  cpufreq: Preserve policy structure across suspend/resume
  cpufreq: Introduce a flag ('frozen') to separate full vs temporary init/teardown
  cpufreq: Extract the handover of policy cpu to a helper function
  cpufreq: Extract non-interface related stuff from cpufreq_add_dev_interface
  cpufreq: Add helper to perform alloc/free of policy structure
  cpufreq: Fix misplaced call to cpufreq_update_policy()
Merge branch 'acpi-pm-next' into linux-next

* acpi-pm-next:
  ACPI / PM: Use ACPI_STATE_D3_COLD instead of ACPI_STATE_D3 everywhere
  ACPI / PM: Make messages in acpi_device_set_power() print device names
  ACPI / PM: Only set power states of devices that are power manageable
Merge branch 'acpi-assorted-next' into linux-next

* acpi-assorted-next:
  ACPI: blacklist win8 OSI for ASUS Zenbok Prime UX31A
  ACPI: Move acpi_bus_get_device() from bus.c to scan.c