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

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