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/*
* Linux I/O port management.
* Copyright (C) 1995 Shantanu Goel.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/ioport.h>
#define NPORTS 65536
#define BITS_PER_WORD 32
#define NWORDS (NPORTS / BITS_PER_WORD)
/*
* This bitmap keeps track of all allocated ports.
* A bit is set if the port has been allocated.
*/
static unsigned port_bitmap[NWORDS];
void snarf_region(unsigned, unsigned);
/*
* Check if a region is available for use.
*/
int
check_region(unsigned port, unsigned size)
{
unsigned i;
for (i = port; i < port + size; i++)
if (port_bitmap[i/BITS_PER_WORD] & (1 << (i%BITS_PER_WORD)))
return (1);
return (0);
}
/*
* Allocate a region.
*/
void
request_region(unsigned port, unsigned size, const char *name)
{
unsigned i;
for (i = port; i < port + size; i++)
port_bitmap[i / BITS_PER_WORD] |= 1 << (i % BITS_PER_WORD);
}
/*
* For compatibility with older kernels.
*/
void
snarf_region(unsigned port, unsigned size)
{
request_region(port, size, 0);
}
/*
* Deallocate a region.
*/
void
release_region(unsigned port, unsigned size)
{
unsigned i;
for (i = port; i < port + size; i++)
port_bitmap[i / BITS_PER_WORD] &= ~(1 << (i % BITS_PER_WORD));
}
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