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Edit File: mmtimer.h
/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ /* * Intel Multimedia Timer device interface * * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive * for more details. * * Copyright (c) 2001-2004 Silicon Graphics, Inc. All rights reserved. * * This file should define an interface compatible with the IA-PC Multimedia * Timers Draft Specification (rev. 0.97) from Intel. Note that some * hardware may not be able to safely export its registers to userspace, * so the ioctl interface should support all necessary functionality. * * 11/01/01 - jbarnes - initial revision * 9/10/04 - Christoph Lameter - remove interrupt support * 9/17/04 - jbarnes - remove test program, move some #defines to the driver */ #ifndef _LINUX_MMTIMER_H #define _LINUX_MMTIMER_H /* * Breakdown of the ioctl's available. An 'optional' next to the command * indicates that supporting this command is optional, while 'required' * commands must be implemented if conformance is desired. * * MMTIMER_GETOFFSET - optional * Should return the offset (relative to the start of the page where the * registers are mapped) for the counter in question. * * MMTIMER_GETRES - required * The resolution of the clock in femto (10^-15) seconds * * MMTIMER_GETFREQ - required * Frequency of the clock in Hz * * MMTIMER_GETBITS - required * Number of bits in the clock's counter * * MMTIMER_MMAPAVAIL - required * Returns nonzero if the registers can be mmap'd into userspace, 0 otherwise * * MMTIMER_GETCOUNTER - required * Gets the current value in the counter */ #define MMTIMER_IOCTL_BASE 'm' #define MMTIMER_GETOFFSET _IO(MMTIMER_IOCTL_BASE, 0) #define MMTIMER_GETRES _IOR(MMTIMER_IOCTL_BASE, 1, unsigned long) #define MMTIMER_GETFREQ _IOR(MMTIMER_IOCTL_BASE, 2, unsigned long) #define MMTIMER_GETBITS _IO(MMTIMER_IOCTL_BASE, 4) #define MMTIMER_MMAPAVAIL _IO(MMTIMER_IOCTL_BASE, 6) #define MMTIMER_GETCOUNTER _IOR(MMTIMER_IOCTL_BASE, 9, unsigned long) #endif /* _LINUX_MMTIMER_H */