PM: earlysuspend: Removing dependence on console.

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>
diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig
index 625d653..a70f6c8 100644
--- a/kernel/power/Kconfig
+++ b/kernel/power/Kconfig
@@ -61,6 +61,7 @@
 
 choice
 	prompt "User-space screen access"
+	default FB_EARLYSUSPEND if !FRAMEBUFFER_CONSOLE
 	default CONSOLE_EARLYSUSPEND
 	depends on HAS_EARLYSUSPEND
 
@@ -74,6 +75,14 @@
 		  Register early suspend handler to perform a console switch to
 		  when user-space should stop drawing to the screen and a switch
 		  back when it should resume.
+
+	config FB_EARLYSUSPEND
+		bool "Sysfs interface"
+		depends on HAS_EARLYSUSPEND
+		---help---
+		  Register early suspend handler that notifies and waits for
+		  user-space through sysfs when user-space should stop drawing
+		  to the screen and notifies user-space when it should resume.
 endchoice
 
 config HIBERNATE_CALLBACKS