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* 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) 1995, 96, 99, 2001 Ralf Baechle
#ifndef _ASM_IOCTL_H
#define _ASM_IOCTL_H
* The original linux ioctl numbering scheme was just a general
* "anything goes" setup, where more or less random numbers were
* assigned. Sorry, I was clueless when I started out on this.
* On the alpha, we'll try to clean it up a bit, using a more sane
* ioctl numbering, and also trying to be compatible with OSF/1 in
* the process. I'd like to clean it up for the i386 as well, but
* it's so painful recognizing both the new and the old numbers..
* The same applies for for the MIPS ABI; in fact even the macros
* from Linux/Alpha fit almost perfectly.
#define _IOC_NRBITS 8
#define _IOC_TYPEBITS 8
#define _IOC_SIZEBITS 13
#define _IOC_DIRBITS 3
#define _IOC_NRMASK ((1 << _IOC_NRBITS)-1)
#define _IOC_TYPEMASK ((1 << _IOC_TYPEBITS)-1)
#define _IOC_SIZEMASK ((1 << _IOC_SIZEBITS)-1)
#define _IOC_DIRMASK ((1 << _IOC_DIRBITS)-1)
#define _IOC_NRSHIFT 0
* Direction bits _IOC_NONE could be 0, but OSF/1 gives it a bit.
* And this turns out useful to catch old ioctl numbers in header
* files for us.
#define _IOC_NONE 1U
#define _IOC_READ 2U
#define _IOC_WRITE 4U
* The following are included for compatibility
#define _IOC_VOID 0x20000000
#define _IOC_OUT 0x40000000
#define _IOC_IN 0x80000000
#define _IOC(dir, type, nr, size) \
(((dir) << _IOC_DIRSHIFT) | \
((type) << _IOC_TYPESHIFT) | \
((nr) << _IOC_NRSHIFT) | \
((size) << _IOC_SIZESHIFT))
/* provoke compile error for invalid uses of size argument */
extern unsigned int __invalid_size_argument_for_IOC;
#define _IOC_TYPECHECK(t) \
((sizeof(t) == sizeof(t[1]) && \
sizeof(t) < (1 << _IOC_SIZEBITS)) ? \
sizeof(t) : __invalid_size_argument_for_IOC)
/* used to create numbers */
#define _IO(type, nr) _IOC(_IOC_NONE, (type), (nr), 0)
#define _IOR(type, nr, size) _IOC(_IOC_READ, (type), (nr), (_IOC_TYPECHECK(size)))
#define _IOW(type, nr, size) _IOC(_IOC_WRITE, (type), (nr), (_IOC_TYPECHECK(size)))
#define _IOWR(type, nr, size) _IOC(_IOC_READ|_IOC_WRITE, (type), (nr), (_IOC_TYPECHECK(size)))
#define _IOR_BAD(type, nr, size) _IOC(_IOC_READ, (type), (nr), sizeof(size))
#define _IOW_BAD(type, nr, size) _IOC(_IOC_WRITE, (type), (nr), sizeof(size))
#define _IOWR_BAD(type, nr, size) _IOC(_IOC_READ|_IOC_WRITE, (type), (nr), sizeof(size))
/* used to decode them.. */
#define _IOC_DIR(nr) (((nr) >> _IOC_DIRSHIFT) & _IOC_DIRMASK)
#define _IOC_TYPE(nr) (((nr) >> _IOC_TYPESHIFT) & _IOC_TYPEMASK)
#define _IOC_NR(nr) (((nr) >> _IOC_NRSHIFT) & _IOC_NRMASK)
#define _IOC_SIZE(nr) (((nr) >> _IOC_SIZESHIFT) & _IOC_SIZEMASK)
/* ...and for the drivers/sound files... */
#endif /* _ASM_IOCTL_H */