release/src-rt-6.x.4708/linux/linux-2.6.36/arch/arm/mach-s3c2410/gpio.c

   1 /* linux/arch/arm/mach-s3c2410/gpio.c
   2  *
   3  * Copyright (c) 2004-2006 Simtec Electronics
   4  *      Ben Dooks <ben@simtec.co.uk>
   5  *
   6  * S3C2410 GPIO support
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21  */
  22
  23 #include <linux/kernel.h>
  24 #include <linux/init.h>
  25 #include <linux/module.h>
  26 #include <linux/interrupt.h>
  27 #include <linux/ioport.h>
  28 #include <linux/io.h>
  29
  30 #include <mach/hardware.h>
  31 #include <mach/gpio-fns.h>
  32 #include <asm/irq.h>
  33
  34 #include <mach/regs-gpio.h>
  35
  36 int s3c2410_gpio_irqfilter(unsigned int pin, unsigned int on,
  37                            unsigned int config)
  38 {
  39         void __iomem *reg = S3C24XX_EINFLT0;
  40         unsigned long flags;
  41         unsigned long val;
  42
  43         if (pin < S3C2410_GPG(8) || pin > S3C2410_GPG(15))
  44                 return -EINVAL;
  45
  46         config &= 0xff;
  47
  48         pin -= S3C2410_GPG(8);
  49         reg += pin & ~3;
  50
  51         local_irq_save(flags);
  52
  53         /* update filter width and clock source */
  54
  55         val = __raw_readl(reg);
  56         val &= ~(0xff << ((pin & 3) * 8));
  57         val |= config << ((pin & 3) * 8);
  58         __raw_writel(val, reg);
  59
  60         /* update filter enable */
  61
  62         val = __raw_readl(S3C24XX_EXTINT2);
  63         val &= ~(1 << ((pin * 4) + 3));
  64         val |= on << ((pin * 4) + 3);
  65         __raw_writel(val, S3C24XX_EXTINT2);
  66
  67         local_irq_restore(flags);
  68
  69         return 0;
  70 }
  71
  72 EXPORT_SYMBOL(s3c2410_gpio_irqfilter);