1/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ 2/* 3 * Intel Multimedia Timer device interface 4 * 5 * This file is subject to the terms and conditions of the GNU General Public 6 * License. See the file "COPYING" in the main directory of this archive 7 * for more details. 8 * 9 * Copyright (c) 2001-2004 Silicon Graphics, Inc. All rights reserved. 10 * 11 * This file should define an interface compatible with the IA-PC Multimedia 12 * Timers Draft Specification (rev. 0.97) from Intel. Note that some 13 * hardware may not be able to safely export its registers to userspace, 14 * so the ioctl interface should support all necessary functionality. 15 * 16 * 11/01/01 - jbarnes - initial revision 17 * 9/10/04 - Christoph Lameter - remove interrupt support 18 * 9/17/04 - jbarnes - remove test program, move some #defines to the driver 19 */ 20 21#ifndef _LINUX_MMTIMER_H 22#define _LINUX_MMTIMER_H 23 24/* 25 * Breakdown of the ioctl's available. An 'optional' next to the command 26 * indicates that supporting this command is optional, while 'required' 27 * commands must be implemented if conformance is desired. 28 * 29 * MMTIMER_GETOFFSET - optional 30 * Should return the offset (relative to the start of the page where the 31 * registers are mapped) for the counter in question. 32 * 33 * MMTIMER_GETRES - required 34 * The resolution of the clock in femto (10^-15) seconds 35 * 36 * MMTIMER_GETFREQ - required 37 * Frequency of the clock in Hz 38 * 39 * MMTIMER_GETBITS - required 40 * Number of bits in the clock's counter 41 * 42 * MMTIMER_MMAPAVAIL - required 43 * Returns nonzero if the registers can be mmap'd into userspace, 0 otherwise 44 * 45 * MMTIMER_GETCOUNTER - required 46 * Gets the current value in the counter 47 */ 48#define MMTIMER_IOCTL_BASE 'm' 49 50#define MMTIMER_GETOFFSET _IO(MMTIMER_IOCTL_BASE, 0) 51#define MMTIMER_GETRES _IOR(MMTIMER_IOCTL_BASE, 1, unsigned long) 52#define MMTIMER_GETFREQ _IOR(MMTIMER_IOCTL_BASE, 2, unsigned long) 53#define MMTIMER_GETBITS _IO(MMTIMER_IOCTL_BASE, 4) 54#define MMTIMER_MMAPAVAIL _IO(MMTIMER_IOCTL_BASE, 6) 55#define MMTIMER_GETCOUNTER _IOR(MMTIMER_IOCTL_BASE, 9, unsigned long) 56 57#endif /* _LINUX_MMTIMER_H */ 58