cpuidle: Combine cpuidle_enabled() with cpuidle_select()

Since both cpuidle_enabled() and cpuidle_select() are only called by
cpuidle_idle_call(), it is not really useful to keep them separate
and combining them will help to avoid complicating cpuidle_idle_call()
even further if governors are changed to return error codes sometimes.

This code modification shouldn't lead to any functional changes.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpuidle / menu: Return (-1) if there are no suitable states

If there is a PM QoS latency limit and all of the sufficiently shallow
C-states are disabled, the cpuidle menu governor returns 0 which on
some systems is CPUIDLE_DRIVER_STATE_START and shouldn't be returned
if that C-state has been disabled.

Fix the issue by modifying the menu governor to return (-1) in such
situations.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpuidle / menu: move repeated correction factor check to init

In menu_select function we check for correction factor every time.
If it is zero we are initializing to unity. Hence move it to init function
and initialise by unity, hence avoid repeated comparisons.

Signed-off-by: Chander Kashyap <chander.kashyap@linaro.org>
Reviewed-by: Tuukka Tikkanen <tuukka.tikkanen@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI: Revert "ACPI: Remove CONFIG_ACPI_PROCFS_POWER and cm_sbsc.c"

The commit 1e2d9cd and 7d7ee95 remove ACPI Proc Battery
directory and breaks some old userspace tools. This patch
is to revert 7d7ee95.

Fixes: 7d7ee958867a (ACPI: Remove CONFIG_ACPI_PROCFS_POWER and cm_sbsc.c)
Cc: 3.13+ <stable@vger.kernel.org> # 3.13+
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI: Revert "ACPI / Battery: Remove battery's proc directory"

The commit 1e2d9cd and 7d7ee95 remove ACPI Proc Battery
directory and breaks some old userspace tools. This patch
is to revert commit 1e2d9cd.

Fixes: 1e2d9cdfb449 (ACPI / Battery: Remove battery's proc directory)
Cc: 3.13+ <stable@vger.kernel.org> # 3.13+
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI / video: Add use_native_backlight quirks for more systems

ThinkPad T430: extend the T430s entry to also cover the T430 (note we also
have another entry for T430's with a different DMI_PRODUCT_VERSION).

ThinkPad T430
Reported-and-tested-by: edm <fuffi.il.fuffo@gmail.com>
References: https://bugzilla.kernel.org/show_bug.cgi?id=51231

Thinkpad T530
Reported-and-tested-by: Balint Szigeti <balint.szgt@gmail.com>
References: https://bugzilla.redhat.com/show_bug.cgi?id=1089545

Acer Aspire 5742G
Reported-and-tested-by: AnAkkk <anakin.cs@gmail.com>
References: https://bugzilla.kernel.org/show_bug.cgi?id=35622

Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Merge branches 'acpi-video' and 'acpi-proc'

* acpi-video:
  ACPI / video: Add use_native_backlight quirks for more systems

* acpi-proc:
  ACPI: Revert "ACPI / Battery: Remove battery's proc directory"
  ACPI: Revert "ACPI: Remove CONFIG_ACPI_PROCFS_POWER and cm_sbsc.c"
Merge branch 'pm-cpuidle' into linux-next

* pm-cpuidle:
  cpuidle / menu: move repeated correction factor check to init
  cpuidle / menu: Return (-1) if there are no suitable states
  cpuidle: Combine cpuidle_enabled() with cpuidle_select()