i8253: Consolidate all kernel definitions of i8253_lock

Move them to drivers/clocksource/i8253.c and remove the
implementations in arch/

[ tglx: Avoid the extra file in lib - folded arch patches in. The
  export will become conditional in a later step ]

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Link: http://lkml.kernel.org/r/20110601180610.221426078@duck.linux-mips.net
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

arch/arm/mach-footbridge/isa-timer.c

@@ -19,8 +19,6 @@
 
 #include "common.h"
 
-DEFINE_RAW_SPINLOCK(i8253_lock);
-
 static void pit_set_mode(enum clock_event_mode mode,
 	struct clock_event_device *evt)
 {

arch/mips/kernel/i8253.c

@@ -16,9 +16,6 @@
 #include <asm/io.h>
 #include <asm/time.h>
 
-DEFINE_RAW_SPINLOCK(i8253_lock);
-EXPORT_SYMBOL(i8253_lock);
-
 /*
  * Initialize the PIT timer.
  *

arch/x86/Kconfig

@@ -70,6 +70,7 @@ config X86
 	select IRQ_FORCED_THREADING
 	select USE_GENERIC_SMP_HELPERS if SMP
 	select HAVE_BPF_JIT if (X86_64 && NET)
+	select I8253_LOCK
 
 config INSTRUCTION_DECODER
 	def_bool (KPROBES || PERF_EVENTS)

arch/x86/kernel/i8253.c

@@ -16,9 +16,6 @@
 #include <asm/hpet.h>
 #include <asm/smp.h>
 
-DEFINE_RAW_SPINLOCK(i8253_lock);
-EXPORT_SYMBOL(i8253_lock);
-
 /*
  * HPET replaces the PIT, when enabled. So we need to know, which of
  * the two timers is used

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

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

drivers/clocksource/i8253.c

@@ -6,9 +6,19 @@
 #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
@@ -86,3 +96,4 @@ int __init clocksource_i8253_init(void)
 {
 	return clocksource_register_hz(&i8253_cs, PIT_TICK_RATE);
 }
+#endif

init/Kconfig

@@ -1002,6 +1002,7 @@ config ELF_CORE
 config PCSPKR_PLATFORM
 	bool "Enable PC-Speaker support" if EXPERT
 	depends on ALPHA || X86 || MIPS || PPC_PREP || PPC_CHRP || PPC_PSERIES
+	select I8253_LOCK
 	default y
 	help
           This option allows to disable the internal PC-Speaker