Change-Id: Ic944e3b3d3bc53eddc6fd0963565fd072cac373c
Signed-off-by: Erik Gilling <konkers@android.com>

Signed-off-by: Mike Chan <mike@android.com>

Rather than signaling a full update of the display from userspace via a
console switch, this patch introduces 2 files int /sys/power,
wait_for_fb_sleep and wait_for_fb_wake.  Reading these files will block
until the requested state has been entered.  When a read from
wait_for_fb_sleep returns userspace should stop drawing.  When
wait_for_fb_wake returns, it should do a full update.  If either are called
when the fb driver is already in the requested state, they will return
immediately.

Signed-off-by: Rebecca Schultz <rschultz@google.com>
Signed-off-by: Arve Hjønnevåg <arve@android.com>

Signed-off-by: Arve Hjønnevåg <arve@android.com>

Avoids a problem where the device sometimes hangs for 20 seconds
before the screen is turned on.

This adds /sys/power/wake_lock and /sys/power/wake_unlock.
Writing a string to wake_lock creates a wake lock the
first time is sees a string and locks it. Optionally, the
string can be followed by a timeout.
To unlock the wake lock, write the same string to wake_unlock.

If EARLYSUSPEND is enabled then writes to /sys/power/state no longer
blocks, and the kernel will try to enter the requested state every
time no wakelocks are held. Write "on" to resume normal operation.

PM: wakelock: Replace expire work with a timer

The expire work function did not work in the normal case.

Signed-off-by: Arve Hjønnevåg <arve@android.com>

Move the sysdev_suspend/resume from the callee to the callers, with
no real change in semantics, so that we can rework the disabling of
interrupts during suspend/hibernation.

This is based on an earlier patch from Linus.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>