ideapad: add Lenovo IdeaPad Z570 support (part 2)

The patch adds support for Lenovo IdeaPad Z570 laptop. It makes all special
keys working, adds possibility to control fan like Windows does, controls
Touchpad Disabled LED, toggles touchpad state via keyboard controller and
corrects touchpad behavior on resume from suspend. It is new, modified
version of patch. Now it does not depend on psmouse and does not need patching
of input subsystem.

Signed-off-by: Maxim Mikityanskiy <maxtram95@gmail.com>

This is part 2 for touchpad toggle

Signed-off-by: Ike Panhc <ike.pan@canonical.com>
Signed-off-by: Matthew Garrett <mjg@redhat.com>
diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
index 637074d..c86bae8 100644
--- a/drivers/platform/x86/Kconfig
+++ b/drivers/platform/x86/Kconfig
@@ -289,6 +289,7 @@
 	tristate "Lenovo IdeaPad Laptop Extras"
 	depends on ACPI
 	depends on RFKILL && INPUT
+	depends on SERIO_I8042
 	select INPUT_SPARSEKMAP
 	help
 	  This is a driver for the rfkill switches on Lenovo IdeaPad netbooks.