Add support driver for Intel Rapid Start Technology

Intel Rapid Start Technology is a firmware-based suspend-to-disk
implementation. Once placed in S3, the device will wake once either a
timeout elapses or the battery reaches a critical level. It will then resume
to the firmware and copy the contents of RAM to a specialised partition, and
then power off the machine. If the user turns the machine back on the
firmware will copy the contents of the partition back to RAM and then resume
from S3 as normal.

This driver provides an interface for configuring the wakeup events and
timeout. It still requires firmware support and an appropriate suspend
partition.

Signed-off-by: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
index 37645b9..36057f4 100644
--- a/drivers/platform/x86/Kconfig
+++ b/drivers/platform/x86/Kconfig
@@ -782,6 +782,18 @@
 	  graphics as well as the backlight. Currently only backlight
 	  control is supported by the driver.
 
+config INTEL_RST
+        tristate "Intel Rapid Start Technology Driver"
+	depends on ACPI
+	---help---
+	  This driver provides support for modifying paramaters on systems
+	  equipped with Intel's Rapid Start Technology. When put in an ACPI
+	  sleep state, these devices will wake after either a configured
+	  timeout or when the system battery reaches a critical state,
+	  automatically copying memory contents to disk. On resume, the
+	  firmware will copy the memory contents back to RAM and resume the OS
+	  as usual.
+
 config PVPANIC
 	tristate "pvpanic device support"
 	depends on ACPI