ACPI / power: Release resource_lock after acpi_power_get_state() return error

In acpi_resume_power_resources() resource_lock should be released
when acpi_power_get_state() fails and before passing to next power
resource on the list.

Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI: remove /proc/acpi/event from ACPI_BUTTON help

Commit 1696d9d (ACPI: Remove the old /proc/acpi/event interface)
left /proc/acpi/event in the ACPI_BUTTON help in Kconfig, so
remove it from there.

[rjw: Changelog]
Signed-off-by: Krzysztof Mazur <krzysiek@podlesie.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq / intel_pstate: Fix max_perf_pct on resume

If the system is suspended while max_perf_pct is less than 100 percent
or no_turbo set policy->{min,max} will be set incorrectly with scaled
values which turn the scaled values into hard limits.

References: https://bugzilla.kernel.org/show_bug.cgi?id=61241
Reported-by: Patrick Bartels <petzicus@googlemail.com>
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Cc: 3.9+ <stable@vger.kernel.org> # 3.9+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
intel_pstate: Fix type mismatch warning

The expression in line 398 of intel_pstate.c causes the following
warning to be emitted:

drivers/cpufreq/intel_pstate.c:398:3: warning: left shift count >= width of type

which happens because unsigned long is 32-bit on some architectures.

Fix that by using a helper u64 variable and simplify the code
slightly.

Tested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI / power: Drop automaitc resume of power resource dependent devices

The mechanism causing devices depending on a given power resource
(that is, devices that can be in D0 only if that power resource is
on) to be resumed automatically when the power resource is turned
on (and their "inferred" power state becomes D0 as a result) is
inherently racy and in fact unnecessary.

It is racy, because if the power resource is turned on and then
immediately off, the device resume triggered by the first transition
to "on" may still happen, causing the power resource to be turned
on again.  That again will trigger the "resume of dependent devices"
mechanism, but if the devices in question are not in use, they will
be suspended in the meantime causing the power resource to be turned
off.  However, the "resume of dependent devices" will next resume
them again and so on.  In some cases (USB port PM in particular) that
leads to an endless busy loop of flipping the resource on and off
continuously.

It is needless, because whoever turns a power resource on will most
likely turn it off at some point and the devices that go into "D0"
as a result of turning it on will then go back into D3cold
(generally, the state they were in before).

Moreover, turning on all power resources a device needs to go into
D0 is not sufficient for a full transition into D0 in general.
Namely, _PS0 may need to be executed in addition to that in some
cases.  This means that the whole rationale of the "resume of
dependent devices" mechanism was incorrect to begin with and it's
best to remove it entirely.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq: s3c64xx: Rename index to driver_data

The index field of cpufreq_frequency_table has been renamed to
driver_data by commit 5070158 (cpufreq: rename index as driver_data
in cpufreq_frequency_table).

This patch updates the s3c64xx driver to match.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Cc: 3.11+ <stable@vger.kernel.org> # 3.11+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ATA / ACPI: remove power dependent device handling

Previously, we wanted SCSI devices corrsponding to ATA devices to
be runtime resumed when the power resource for those ATA device was
turned on by some other device, so we added the SCSI device to the
dependent device list of the ATA device's ACPI node.  However, this
code has no effect after commit 41863fc (ACPI / power: Drop automaitc
resume of power resource dependent devices) and the mechanism it was
supposed to implement is regarded as a bad idea now, so drop it.

[rjw: Changelog]
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI / PM: Drop two functions that are not used any more

Two functions defined in device_pm.c, acpi_dev_pm_add_dependent()
and acpi_dev_pm_remove_dependent(), have no callers and may be
dropped, so drop them.

Moreover, they are the only functions adding entries to and removing
entries from the power_dependent list in struct acpi_device, so drop
that list too.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Merge branch 'pm-fixes'

* pm-fixes:
  cpufreq: s3c64xx: Rename index to driver_data
  intel_pstate: Fix type mismatch warning
  cpufreq / intel_pstate: Fix max_perf_pct on resume
Merge branch 'acpi-fixes'

* acpi-fixes:
  ACPI / PM: Drop two functions that are not used any more
  ATA / ACPI: remove power dependent device handling
  ACPI / power: Drop automaitc resume of power resource dependent devices
  ACPI: remove /proc/acpi/event from ACPI_BUTTON help
  ACPI / power: Release resource_lock after acpi_power_get_state() return error
Merge tag 'pm+acpi-3.12-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI and power management fixes from Rafael Wysocki:

 - intel_pstate fix for misbehavior after system resume if sysfs
   attributes are set in a specific way before the corresponding suspend
   from Dirk Brandewie.

 - A recent intel_pstate fix has no effect if unsigned long is 32-bit,
   so fix it up to cover that case as well.

 - The s3c64xx cpufreq driver was not updated when the index field of
   struct cpufreq_frequency_table was replaced with driver_data, so
   update it now.  From Charles Keepax.

 - The Kconfig help text for ACPI_BUTTON still refers to
   /proc/acpi/event that has been dropped recently, so modify it to
   remove that reference.  From Krzysztof Mazur.

 - A Lan Tianyu's change adds a missing mutex unlock to an error code
   path in acpi_resume_power_resources().

 - Some code related to ACPI power resources, whose very purpose is
   questionable to put it lightly, turns out to cause problems to happen
   during testing on real systems, so remove it completely (we may
   revisit that in the future if there's a compelling enough reason).
   From Rafael J Wysocki and Aaron Lu.

* tag 'pm+acpi-3.12-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI / PM: Drop two functions that are not used any more
  ATA / ACPI: remove power dependent device handling
  cpufreq: s3c64xx: Rename index to driver_data
  ACPI / power: Drop automaitc resume of power resource dependent devices
  intel_pstate: Fix type mismatch warning
  cpufreq / intel_pstate: Fix max_perf_pct on resume
  ACPI: remove /proc/acpi/event from ACPI_BUTTON help
  ACPI / power: Release resource_lock after acpi_power_get_state() return error