2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
6 * Machine specific IO port address definition for generic.
7 * Written by Osamu Tomita <tomita@cinet.co.jp>
9 #ifndef __LINUX_I8253_H
10 #define __LINUX_I8253_H
12 #include <linux/param.h>
13 #include <linux/spinlock.h>
14 #include <linux/timex.h>
16 /* i8253A PIT registers */
21 #define PIT_LATCH ((PIT_TICK_RATE + HZ/2) / HZ)
23 extern raw_spinlock_t i8253_lock;
24 extern struct clock_event_device i8253_clockevent;
25 extern void clockevent_i8253_init(bool oneshot);
27 extern void setup_pit_timer(void);
29 #endif /* __LINUX_I8253_H */