arch/arm/plat-s3c24xx/gpio.c

   1 /* linux/arch/arm/plat-s3c24xx/gpio.c
   2  *
   3  * Copyright (c) 2004-2010 Simtec Electronics
   4  *      Ben Dooks <ben@simtec.co.uk>
   5  *
   6  * S3C24XX 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/gpio.h>
  29 #include <linux/io.h>
  30
  31 #include <mach/hardware.h>
  32 #include <mach/gpio-fns.h>
  33 #include <asm/irq.h>
  34
  35 #include <mach/regs-gpio.h>
  36
  37 #include <plat/gpio-core.h>
  38
  39 /* gpiolib wrappers until these are totally eliminated */
  40
  41 void s3c2410_gpio_pullup(unsigned int pin, unsigned int to)
  42 {
  43         int ret;
  44
  45         WARN_ON(to);    /* should be none of these left */
  46
  47         if (!to) {
  48                 /* if pull is enabled, try first with up, and if that
  49                  * fails, try using down */
  50
  51                 ret = s3c_gpio_setpull(pin, S3C_GPIO_PULL_UP);
  52                 if (ret)
  53                         s3c_gpio_setpull(pin, S3C_GPIO_PULL_DOWN);
  54         } else {
  55                 s3c_gpio_setpull(pin, S3C_GPIO_PULL_NONE);
  56         }
  57 }
  58 EXPORT_SYMBOL(s3c2410_gpio_pullup);
  59
  60 void s3c2410_gpio_setpin(unsigned int pin, unsigned int to)
  61 {
  62         /* do this via gpiolib until all users removed */
  63
  64         gpio_request(pin, "temporary");
  65         gpio_set_value(pin, to);
  66         gpio_free(pin);
  67 }
  68
  69 EXPORT_SYMBOL(s3c2410_gpio_setpin);
  70
  71 unsigned int s3c2410_gpio_getpin(unsigned int pin)
  72 {
  73         struct s3c_gpio_chip *chip = s3c_gpiolib_getchip(pin);
  74         unsigned long offs = pin - chip->chip.base;
  75
  76         return __raw_readl(chip->base + 0x04) & (1<< offs);
  77 }
  78
  79 EXPORT_SYMBOL(s3c2410_gpio_getpin);
  80
  81 unsigned int s3c2410_modify_misccr(unsigned int clear, unsigned int change)
  82 {
  83         unsigned long flags;
  84         unsigned long misccr;
  85
  86         local_irq_save(flags);
  87         misccr = __raw_readl(S3C24XX_MISCCR);
  88         misccr &= ~clear;
  89         misccr ^= change;
  90         __raw_writel(misccr, S3C24XX_MISCCR);
  91         local_irq_restore(flags);
  92
  93         return misccr;
  94 }
  95
  96 EXPORT_SYMBOL(s3c2410_modify_misccr);