i8253: Consolidate definitions of PIT_LATCH

x86 defines PIT_LATCH as LATCH which in <linux/timex.h> is defined as
((CLOCK_TICK_RATE + HZ/2) / HZ) and <asm/timex.h> again defines
CLOCK_TICK_RATE as PIT_TICK_RATE.

MIPS defines PIT_LATCH as LATCH which in <linux/timex.h> is defined as
((CLOCK_TICK_RATE + HZ/2) / HZ) and <asm/timex.h> again defines
CLOCK_TICK_RATE as 1193182.

ARM defines PITCH_LATCH as ((PIT_TICK_RATE + HZ / 2) / HZ) - and that's
the sanest thing and equivalent to above definitions so use that as the
new definition in <linux/i8253.h>.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-mips@linux-mips.org
Link: http://lkml.kernel.org/r/20110601180610.832810002@duck.linux-mips.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 4 insertions, 0 deletions

diff --git a/include/linux/i8253.h b/include/linux/i8253.h
index 13048d335368..1ec6323a1507 100644
--- a/include/linux/i8253.h
+++ b/include/linux/i8253.h
@@ -9,7 +9,9 @@
 #ifndef __LINUX_I8253_H
 #define __LINUX_I8253_H
 
+#include <linux/param.h>
 #include <linux/spinlock.h>
+#include <linux/timex.h>
 #include <asm/i8253.h>
 
 /* i8253A PIT registers */
@@ -17,6 +19,8 @@
 #define PIT_CH0         0x40
 #define PIT_CH2         0x42
 
+#define PIT_LATCH       ((PIT_TICK_RATE + HZ/2) / HZ)
+
 #define inb_pit         inb_p
 #define outb_pit        outb_p