1/*
2 * Intel Multimedia Timer device interface
3 *
4 * This file is subject to the terms and conditions of the GNU General Public
5 * License.  See the file "COPYING" in the main directory of this archive
6 * for more details.
7 *
8 * Copyright (c) 2001-2004 Silicon Graphics, Inc.  All rights reserved.
9 *
10 * This file should define an interface compatible with the IA-PC Multimedia
11 * Timers Draft Specification (rev. 0.97) from Intel.  Note that some
12 * hardware may not be able to safely export its registers to userspace,
13 * so the ioctl interface should support all necessary functionality.
14 *
15 * 11/01/01 - jbarnes - initial revision
16 * 9/10/04 - Christoph Lameter - remove interrupt support
17 * 9/17/04 - jbarnes - remove test program, move some #defines to the driver
18 */
19
20#ifndef _LINUX_MMTIMER_H
21#define _LINUX_MMTIMER_H
22
23/*
24 * Breakdown of the ioctl's available.  An 'optional' next to the command
25 * indicates that supporting this command is optional, while 'required'
26 * commands must be implemented if conformance is desired.
27 *
28 * MMTIMER_GETOFFSET - optional
29 *   Should return the offset (relative to the start of the page where the
30 *   registers are mapped) for the counter in question.
31 *
32 * MMTIMER_GETRES - required
33 *   The resolution of the clock in femto (10^-15) seconds
34 *
35 * MMTIMER_GETFREQ - required
36 *   Frequency of the clock in Hz
37 *
38 * MMTIMER_GETBITS - required
39 *   Number of bits in the clock's counter
40 *
41 * MMTIMER_MMAPAVAIL - required
42 *   Returns nonzero if the registers can be mmap'd into userspace, 0 otherwise
43 *
44 * MMTIMER_GETCOUNTER - required
45 *   Gets the current value in the counter
46 */
47#define MMTIMER_IOCTL_BASE 'm'
48
49#define MMTIMER_GETOFFSET _IO(MMTIMER_IOCTL_BASE, 0)
50#define MMTIMER_GETRES _IOR(MMTIMER_IOCTL_BASE, 1, unsigned long)
51#define MMTIMER_GETFREQ _IOR(MMTIMER_IOCTL_BASE, 2, unsigned long)
52#define MMTIMER_GETBITS _IO(MMTIMER_IOCTL_BASE, 4)
53#define MMTIMER_MMAPAVAIL _IO(MMTIMER_IOCTL_BASE, 6)
54#define MMTIMER_GETCOUNTER _IOR(MMTIMER_IOCTL_BASE, 9, unsigned long)
55
56#endif /* _LINUX_MMTIMER_H */
57