vidix/sysdep/pci_mach386.c

   1 /*
   2    This file is based on:
   3    $XFree86: xc/programs/Xserver/hw/xfree86/etc/scanpci.c,v 3.34.2.17 1998/11/10 11:55:40 dawes Exp $
   4    Modified for readability by Nick Kurshev
   5 */
   6 /*
   7  * Copyright 1995 by Robin Cutshaw <robin@XFree86.Org>
   8  *
   9  * Permission to use, copy, modify, distribute, and sell this software and its
  10  * documentation for any purpose is hereby granted without fee, provided that
  11  * the above copyright notice appear in all copies and that both that
  12  * copyright notice and this permission notice appear in supporting
  13  * documentation, and that the names of the above listed copyright holder(s)
  14  * not be used in advertising or publicity pertaining to distribution of
  15  * the software without specific, written prior permission.  The above listed
  16  * copyright holder(s) make(s) no representations about the suitability of this
  17  * software for any purpose.  It is provided "as is" without express or
  18  * implied warranty.
  19  *
  20  * THE ABOVE LISTED COPYRIGHT HOLDER(S) DISCLAIM(S) ALL WARRANTIES WITH REGARD
  21  * TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
  22  * AND FITNESS, IN NO EVENT SHALL THE ABOVE LISTED COPYRIGHT HOLDER(S) BE
  23  * LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY
  24  * DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
  25  * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
  26  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  27  */
  28
  29 #include <errno.h>
  30
  31 static int io_fd;
  32
  33 static __inline__ int enable_os_io(void)
  34 {
  35     io_fd = -1 ;
  36     if ((io_fd = open("/dev/iopl", O_RDWR, 0)) < 0) {
  37         perror("/dev/iopl");
  38         return errno;
  39     }
  40     return 0;
  41 }
  42
  43 static __inline__ int disable_os_io(void)
  44 {
  45     close(io_fd);
  46     return 0;
  47 }