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
8 * Copyright (C) 1995, 1996, 2001 by Ralf Baechle
10 #ifndef __ASM_MIPS_IOCTL_H
11 #define __ASM_MIPS_IOCTL_H
14 * The original linux ioctl numbering scheme was just a general
15 * "anything goes" setup, where more or less random numbers were
16 * assigned. Sorry, I was clueless when I started out on this.
18 * On the alpha, we'll try to clean it up a bit, using a more sane
19 * ioctl numbering, and also trying to be compatible with OSF/1 in
20 * the process. I'd like to clean it up for the i386 as well, but
21 * it's so painful recognizing both the new and the old numbers..
23 * The same applies for for the MIPS ABI; in fact even the macros
24 * from Linux/Alpha fit almost perfectly.
28 #define _IOC_TYPEBITS 8
29 #define _IOC_SIZEBITS 13
30 #define _IOC_DIRBITS 3
32 #define _IOC_NRMASK ((1 << _IOC_NRBITS)-1)
33 #define _IOC_TYPEMASK ((1 << _IOC_TYPEBITS)-1)
34 #define _IOC_SIZEMASK ((1 << _IOC_SIZEBITS)-1)
35 #define _IOC_DIRMASK ((1 << _IOC_DIRBITS)-1)
37 #define _IOC_NRSHIFT 0
38 #define _IOC_TYPESHIFT (_IOC_NRSHIFT+_IOC_NRBITS)
39 #define _IOC_SIZESHIFT (_IOC_TYPESHIFT+_IOC_TYPEBITS)
40 #define _IOC_DIRSHIFT (_IOC_SIZESHIFT+_IOC_SIZEBITS)
43 * Direction bits _IOC_NONE could be 0, but OSF/1 gives it a bit.
44 * And this turns out useful to catch old ioctl numbers in header
52 * The following are included for compatibility
54 #define _IOC_VOID 0x20000000
55 #define _IOC_OUT 0x40000000
56 #define _IOC_IN 0x80000000
57 #define _IOC_INOUT (IOC_IN|IOC_OUT)
59 #define _IOC(dir,type,nr,size) \
60 (((dir) << _IOC_DIRSHIFT) | \
61 ((type) << _IOC_TYPESHIFT) | \
62 ((nr) << _IOC_NRSHIFT) | \
63 ((size) << _IOC_SIZESHIFT))
65 /* used to create numbers */
66 #define _IO(type,nr) _IOC(_IOC_NONE,(type),(nr),0)
67 #define _IOR(type,nr,size) _IOC(_IOC_READ,(type),(nr),sizeof(size))
68 #define _IOW(type,nr,size) _IOC(_IOC_WRITE,(type),(nr),sizeof(size))
69 #define _IOWR(type,nr,size) _IOC(_IOC_READ|_IOC_WRITE,(type),(nr),sizeof(size))
71 /* used to decode them.. */
72 #define _IOC_DIR(nr) (((nr) >> _IOC_DIRSHIFT) & _IOC_DIRMASK)
73 #define _IOC_TYPE(nr) (((nr) >> _IOC_TYPESHIFT) & _IOC_TYPEMASK)
74 #define _IOC_NR(nr) (((nr) >> _IOC_NRSHIFT) & _IOC_NRMASK)
75 #define _IOC_SIZE(nr) (((nr) >> _IOC_SIZESHIFT) & _IOC_SIZEMASK)
77 /* ...and for the drivers/sound files... */
79 #define IOC_IN (_IOC_WRITE << _IOC_DIRSHIFT)
80 #define IOC_OUT (_IOC_READ << _IOC_DIRSHIFT)
81 #define IOC_INOUT ((_IOC_WRITE|_IOC_READ) << _IOC_DIRSHIFT)
82 #define IOCSIZE_MASK (_IOC_SIZEMASK << _IOC_SIZESHIFT)
83 #define IOCSIZE_SHIFT (_IOC_SIZESHIFT)
85 #endif /* __ASM_MIPS_IOCTL_H */