x86, olpc: Add XO-1 RTC driver

Add a driver to configure the XO-1 RTC via CS5536 MSRs, to be used as a
system wakeup source via olpc-xo1-pm.

Device detection is based on finding the relevant device tree node.

Signed-off-by: Daniel Drake <dsd@laptop.org>
Link: http://lkml.kernel.org/r/1309019658-1712-11-git-send-email-dsd@laptop.org
Acked-by: Andres Salomon <dilinger@queued.net>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: devicetree-discuss@lists.ozlabs.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
diff --git a/arch/x86/platform/olpc/Makefile b/arch/x86/platform/olpc/Makefile
index 1ec5ade..8922b9b 100644
--- a/arch/x86/platform/olpc/Makefile
+++ b/arch/x86/platform/olpc/Makefile
@@ -1,3 +1,4 @@
 obj-$(CONFIG_OLPC)		+= olpc.o olpc_ofw.o olpc_dt.o
 obj-$(CONFIG_OLPC_XO1_PM)		+= olpc-xo1-pm.o xo1-wakeup.o
+obj-$(CONFIG_OLPC_XO1_RTC)	+= olpc-xo1-rtc.o
 obj-$(CONFIG_OLPC_XO1_SCI)	+= olpc-xo1-sci.o