drivers/video/via/via_io.h

   1 /*
   2  * Copyright 1998-2008 VIA Technologies, Inc. All Rights Reserved.
   3  * Copyright 2001-2008 S3 Graphics, Inc. All Rights Reserved.
   4  * Copyright 2010 Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public
   8  * License as published by the Free Software Foundation;
   9  * either version 2, or (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTIES OR REPRESENTATIONS; without even
  13  * the implied warranty of MERCHANTABILITY or FITNESS FOR
  14  * A PARTICULAR PURPOSE.See the GNU General Public License
  15  * for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc.,
  20  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  21  */
  22 /*
  23  * basic io functions
  24  */
  25
  26 #ifndef __VIA_IO_H__
  27 #define __VIA_IO_H__
  28
  29 #include <linux/types.h>
  30 #include <linux/io.h>
  31
  32 /*
  33  * Indexed port operations.  Note that these are all multi-op
  34  * functions; every invocation will be racy if you're not holding
  35  * reg_lock.
  36  */
  37 static inline u8 via_read_reg(u16 port, u8 index)
  38 {
  39         outb(index, port);
  40         return inb(port + 1);
  41 }
  42
  43 static inline void via_write_reg(u16 port, u8 index, u8 data)
  44 {
  45         outb(index, port);
  46         outb(data, port + 1);
  47 }
  48
  49 static inline void via_write_reg_mask(u16 port, u8 index, u8 data, u8 mask)
  50 {
  51         u8 old;
  52
  53         outb(index, port);
  54         old = inb(port + 1);
  55         outb((data & mask) | (old & ~mask), port + 1);
  56 }
  57
  58 #endif /* __VIA_IO_H__ */