target/linux/ar7/files/arch/mips/ar7/gpio.c

   1 /*
   2  * $Id$
   3  *
   4  * Copyright (C) 2007 OpenWrt.org
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  19  */
  20
  21 #include <linux/init.h>
  22 #include <linux/types.h>
  23 #include <linux/module.h>
  24 #include <linux/delay.h>
  25 #include <linux/platform_device.h>
  26 #include <asm/addrspace.h>
  27 #include <asm/io.h>
  28 #include <asm/ar7/ar7.h>
  29 #include <asm/ar7/gpio.h>
  30
  31 static char *ar7_gpio_list[AR7_GPIO_MAX] = { 0, };
  32
  33 int gpio_request(unsigned gpio, char *label)
  34 {
  35         if (gpio >= AR7_GPIO_MAX)
  36                 return -EINVAL;
  37
  38         if (ar7_gpio_list[gpio])
  39                 return -EBUSY;
  40
  41         if (label) {
  42                 ar7_gpio_list[gpio] = label;
  43         } else {
  44                 ar7_gpio_list[gpio] = "busy";
  45         }
  46
  47         return 0;
  48 }
  49 EXPORT_SYMBOL(gpio_request);
  50
  51 void gpio_free(unsigned gpio)
  52 {
  53         BUG_ON(!ar7_gpio_list[gpio]);
  54         ar7_gpio_list[gpio] = NULL;
  55 }
  56 EXPORT_SYMBOL(gpio_free);