Commit 9630bdd (ACPI: Use GPE reference counting to support shared
GPEs) introduced a suspend regression where boxes resume immediately
after being suspended due to the lid or sleep button wakeup status
not being cleared properly.  This happens if the GPEs corresponding
to those devices are not enabled all the time, which apparently is
expected by some BIOSes.

To fix this problem, enable button and lid GPEs unconditionally
during initialization and keep them enabled all the time, regardless
of whether or not the ACPI button driver is used.

References: https://bugzilla.kernel.org/show_bug.cgi?id=27372
Reported-and-tested-by: Ferenc Wágner <wferi@niif.hu>
Cc: stable@kernel.org
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

Some function and variable names are renamed to be consistent with
ACPICA code base.

acpi_raw_enable_gpe -> acpi_ev_add_gpe_reference
acpi_raw_disable_gpe -> acpi_ev_remove_gpe_reference
acpi_gpe_can_wake -> acpi_setup_gpe_for_wake
acpi_gpe_wakeup -> acpi_set_gpe_wake_mask
acpi_update_gpes -> acpi_update_all_gpes
acpi_all_gpes_initialized -> acpi_gbl_all_gpes_initialized
acpi_handler_info -> acpi_gpe_handler_info
...

Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

There are ACPI devices (buttons and the laptop lid) that can wake up
the system from sleep states and have no "physical" companion
devices.  The ACPI subsystem uses two flags, wakeup.state.enabled and
wakeup.flags.always_enabled, for handling those devices, but they
are not accessible through the standard device wakeup infrastructure.
User space can only control them via the /proc/acpi/wakeup interface
that is not really convenient (e.g. the way in which devices are
enabled to wake up the system is not portable between different
systems, because it requires one to know the devices' "names" used in
the system's ACPI tables).

To address this problem, use standard device wakeup flags instead of
the special ACPI flags for handling those devices.  In particular,
use device_set_wakeup_capable() to mark the ACPI wakeup devices
during initialization and use device_set_wakeup_enable() to allow
or disallow them to wake up the system from sleep states.  Rework
the /proc/acpi/wakeup interface to take these changes into account.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>

ACPICA uses reference counters to avoid disabling GPEs too early in
case they have been enabled for many times.  This is done separately
for runtime and for wakeup, but the wakeup GPE reference counter is
not really necessary, because GPEs are only enabled to wake up the
system at the hardware level by acpi_enter_sleep_state().  Thus it
only is necessary to set the corresponding bits in the wakeup enable
masks of these GPEs' registers right before the system enters a sleep
state.  Moreover, the GPE wakeup enable bits can only be set when the
target sleep state of the system is known and they need to be cleared
immediately after wakeup regardless of how many wakeup devices are
associated with a given GPE.

On the basis of the above observations, introduce function
acpi_gpe_wakeup() to be used for setting or clearing the enable bit
corresponding to a given GPE in its enable register's enable_for_wake
mask.  Modify the ACPI suspend and wakeup code the use
acpi_gpe_wakeup() instead of acpi_{enable|disable}_gpe() to set
and clear GPE enable bits in their registers' enable_for_wake masks
during system transitions to a sleep state and back to the working
state, respectively.  [This will allow us to drop the third
argument of acpi_{enable|disable}_gpe() and simplify the GPE
handling code.]

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

To simplify the enabling of wakeup devices during system suspend and
hibernation, merge acpi_enable_wakeup_device_prep() with
acpi_disable_wakeup_device() and remove unnecessary (and no longer
valid) comments from the latter.  Rename acpi_enable_wakeup_device()
to acpi_enable_wakeup_devices() and acpi_disable_wakeup_device()
to acpi_disable_wakeup_devices(), because these functions usually
operate on multiple device objects.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>

After commit 9630bdd9b15d2f489c646d8bc04b60e53eb5ec78
(ACPI: Use GPE reference counting to support shared GPEs) the wakeup
enable mask bits of GPEs are set as soon as the GPEs are enabled to
wake up the system.  Unfortunately, this leads to a regression
reported by Michal Hocko, where a system is woken up from ACPI S5 by
a device that is not supposed to do that, because the wakeup enable
mask bit of this device's GPE is always set when
acpi_enter_sleep_state() calls acpi_hw_enable_all_wakeup_gpes(),
although it should only be set if the device is supposed to wake up
the system from the target state.

To work around this issue, rework the ACPI power management code so
that GPEs are not enabled to wake up the system upfront, but only
during a system state transition when the target state of the system
is known.  [Of course, this means that the reference counting of
"wakeup" GPEs doesn't really make sense and it is sufficient to
set/unset the wakeup mask bits for them during system sleep
transitions.  This will allow us to simplify the GPE handling code
quite a bit, but that change is too intrusive for 2.6.35.]

Fixes https://bugzilla.kernel.org/show_bug.cgi?id=15951

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Reported-and-tested-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Len Brown <len.brown@intel.com>

Use the run_wake flag to mark all devices for which run-time wake-up
events may be generated by the platform.  Introduce a new wake-up
flag, always_enabled, for marking devices that should be permanently
enabled to generate run-time events.  Also, introduce a reference
counter for run-wake devices and a function that will initialize all
of the run-time wake-up fields for given device.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Len Brown <len.brown@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

ACPI GPEs may map to multiple devices.  The current GPE interface
only provides a mechanism for enabling and disabling GPEs, making
it difficult to change the state of GPEs at runtime without extensive
cooperation between devices.

Add an API to allow devices to indicate whether or not they want
their device's GPE to be enabled for both runtime and wakeup events.

Remove the old GPE type handling entirely, which gets rid of various
quirks, like the implicit disabling with GPE type setting. This
requires a small amount of rework in order to ensure that non-wake
GPEs are enabled by default to preserve existing behaviour.

Based on patches from Matthew Garrett <mjg@redhat.com>.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>