The wakeup.prepared flag is used for marking devices that have the
wake-up power already enabled, so that the wake-up power is not
enabled twice in a row for the same device. This assumes, however,
that device wake-up power will only be enabled once, while the device
is being prepared for a system-wide sleep transition, and the second
attempt is made by acpi_enable_wakeup_device_prep().
With the upcoming PCI wake-up rework this assumption will not hold
any more for PCI bridges and the root bridge whose wake-up power
may be enabled as a result of wake-up enable propagation from other
devices (eg. add-on devices that are not associated with any GPEs).
Thus, there may be many attempts to enable wake-up power on a PCI
bridge or the root bridge during a system power state transition
and it's better to replace wakeup.prepared with a reference counter.
Reviewed-by: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Convert acpi_device_lock to a mutex to avoid
a potential race upon access to /proc/acpi/wakeup
Delete the lock entirely in wakeup.c
since it is not necessary (and can not sleep)
Found-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
This patch makes acpi_init() call acpi_wakeup_device_init() directly.
Previously, acpi_wakeup_device_init() was a late_initcall (sequence 7).
acpi_wakeup_device_init() depends on acpi_wakeup_device_list, which
is populated when ACPI devices are enumerated by acpi_init() ->
acpi_scan_init(). Using late_initcall is certainly enough to make
sure acpi_wakeup_device_list is populated, but it is more than
necessary. We can just as easily call acpi_wakeup_device_init()
directly from acpi_init(), which avoids the initcall magic.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
CC: Li Shaohua <shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
A number of things that shouldn't be exposed outside the ACPI core
were declared in include/acpi/acpi_drivers.h, where anybody can
see them. This patch moves those declarations to a new "internal.h"
inside drivers/acpi.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Rafael J. Wysocki