[PATCH] suspend-to-ram: allow video options to be set at runtime

Currently, acpi video options can only be set on kernel command line.  That's
little inflexible; I'd like userland s2ram application that just works, and
modifying kernel command line according to whitelist is not fun.  It is better
to just allow s2ram application to set video options just before suspend
(according to the whitelist).

This implements sysctl to allow setting suspend video options without reboot.

(akpm: Documentation updates for this new sysctl are pending..)

Signed-off-by: Pavel Machek <pavel@suse.cz>
Cc: "Brown, Len" <len.brown@intel.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Documentation/sysctl/kernel.txt

@@ -16,6 +16,7 @@ before actually making adjustments.
 
 Currently, these files might (depending on your configuration)
 show up in /proc/sys/kernel:
+- acpi_video_flags
 - acct
 - core_pattern
 - core_uses_pid
@@ -57,6 +58,15 @@ show up in /proc/sys/kernel:
 
 ==============================================================
 
+acpi_video_flags:
+
+flags
+
+See Doc*/kernel/power/video.txt, it allows mode of video boot to be
+set during run time.
+
+==============================================================
+
 acct:
 
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