/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
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#ifndef _ALPHA_IOCTL_H
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#define _ALPHA_IOCTL_H
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/*
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* The original linux ioctl numbering scheme was just a general
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* "anything goes" setup, where more or less random numbers were
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* assigned. Sorry, I was clueless when I started out on this.
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*
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* On the alpha, we'll try to clean it up a bit, using a more sane
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* ioctl numbering, and also trying to be compatible with OSF/1 in
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* the process. I'd like to clean it up for the i386 as well, but
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* it's so painful recognizing both the new and the old numbers..
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*/
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#define _IOC_NRBITS 8
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#define _IOC_TYPEBITS 8
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#define _IOC_SIZEBITS 13
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#define _IOC_DIRBITS 3
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#define _IOC_NRMASK ((1 << _IOC_NRBITS)-1)
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#define _IOC_TYPEMASK ((1 << _IOC_TYPEBITS)-1)
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#define _IOC_SIZEMASK ((1 << _IOC_SIZEBITS)-1)
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#define _IOC_DIRMASK ((1 << _IOC_DIRBITS)-1)
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#define _IOC_NRSHIFT 0
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#define _IOC_TYPESHIFT (_IOC_NRSHIFT+_IOC_NRBITS)
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#define _IOC_SIZESHIFT (_IOC_TYPESHIFT+_IOC_TYPEBITS)
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#define _IOC_DIRSHIFT (_IOC_SIZESHIFT+_IOC_SIZEBITS)
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/*
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* Direction bits _IOC_NONE could be 0, but OSF/1 gives it a bit.
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* And this turns out useful to catch old ioctl numbers in header
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* files for us.
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*/
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#define _IOC_NONE 1U
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#define _IOC_READ 2U
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#define _IOC_WRITE 4U
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#define _IOC(dir,type,nr,size) \
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((unsigned int) \
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(((dir) << _IOC_DIRSHIFT) | \
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((type) << _IOC_TYPESHIFT) | \
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((nr) << _IOC_NRSHIFT) | \
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((size) << _IOC_SIZESHIFT)))
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/* used to create numbers */
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#define _IO(type,nr) _IOC(_IOC_NONE,(type),(nr),0)
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#define _IOR(type,nr,size) _IOC(_IOC_READ,(type),(nr),sizeof(size))
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#define _IOW(type,nr,size) _IOC(_IOC_WRITE,(type),(nr),sizeof(size))
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#define _IOWR(type,nr,size) _IOC(_IOC_READ|_IOC_WRITE,(type),(nr),sizeof(size))
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/* used to decode them.. */
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#define _IOC_DIR(nr) (((nr) >> _IOC_DIRSHIFT) & _IOC_DIRMASK)
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#define _IOC_TYPE(nr) (((nr) >> _IOC_TYPESHIFT) & _IOC_TYPEMASK)
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#define _IOC_NR(nr) (((nr) >> _IOC_NRSHIFT) & _IOC_NRMASK)
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#define _IOC_SIZE(nr) (((nr) >> _IOC_SIZESHIFT) & _IOC_SIZEMASK)
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/* ...and for the drivers/sound files... */
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#define IOC_IN (_IOC_WRITE << _IOC_DIRSHIFT)
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#define IOC_OUT (_IOC_READ << _IOC_DIRSHIFT)
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#define IOC_INOUT ((_IOC_WRITE|_IOC_READ) << _IOC_DIRSHIFT)
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#define IOCSIZE_MASK (_IOC_SIZEMASK << _IOC_SIZESHIFT)
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#define IOCSIZE_SHIFT (_IOC_SIZESHIFT)
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#endif /* _ALPHA_IOCTL_H */
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