3 files changed, 19 insertions, 2 deletions

diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index 96c921910469..330343bcb67e 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -1,5 +1,11 @@
 config CLKSRC_I8253
         bool
 
+config I8253_LOCK
+        bool
+
+config CLKBLD_I8253
+        def_bool y if CLKSRC_I8253 || I8253_LOCK
+
 config CLKSRC_MMIO
         bool
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index b995942a5060..7922a0cfc99f 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -6,5 +6,5 @@ obj-$(CONFIG_CS5535_CLOCK_EVENT_SRC)	+= cs5535-clockevt.o
 obj-$(CONFIG_SH_TIMER_CMT)      += sh_cmt.o
 obj-$(CONFIG_SH_TIMER_MTU2)     += sh_mtu2.o
 obj-$(CONFIG_SH_TIMER_TMU)      += sh_tmu.o
-obj-$(CONFIG_CLKSRC_I8253)      += i8253.o
+obj-$(CONFIG_CLKBLD_I8253)      += i8253.o
 obj-$(CONFIG_CLKSRC_MMIO)       += mmio.o
diff --git a/drivers/clocksource/i8253.c b/drivers/clocksource/i8253.c
index 33735ebd2dcc..e594f52eb88e 100644
--- a/drivers/clocksource/i8253.c
+++ b/drivers/clocksource/i8253.c
@@ -6,10 +6,20 @@
 #include <linux/io.h>
 #include <linux/spinlock.h>
 #include <linux/timex.h>
-
+#include <linux/module.h>
 #include <linux/i8253.h>
 
 /*
+ * Protects access to I/O ports
+ *
+ * 0040-0043 : timer0, i8253 / i8254
+ * 0061-0061 : NMI Control Register which contains two speaker control bits.
+ */
+DEFINE_RAW_SPINLOCK(i8253_lock);
+EXPORT_SYMBOL(i8253_lock);
+
+#ifdef CONFIG_CLKSRC_I8253
+/*
  * Since the PIT overflows every tick, its not very useful
  * to just read by itself. So use jiffies to emulate a free
  * running counter:
@@ -86,3 +96,4 @@ int __init clocksource_i8253_init(void)
 {
         return clocksource_register_hz(&i8253_cs, PIT_TICK_RATE);
 }
+#endif