LXR linux/arch/arm/plat-iop/gpio.c

   1/*
   2 * arch/arm/plat-iop/gpio.c
   3 * GPIO handling for Intel IOP3xx processors.
   4 *
   5 * Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
   6 *
   7 * This program is free software; you can redistribute it and/or modify
   8 * it under the terms of the GNU General Public License as published by
   9 * the Free Software Foundation; either version 2 of the License, or (at
  10 * your option) any later version.
  11 */
  12
  13#include <linux/device.h>
  14#include <linux/init.h>
  15#include <linux/types.h>
  16#include <linux/errno.h>
  17#include <linux/gpio.h>
  18#include <asm/hardware/iop3xx.h>
  19
  20void gpio_line_config(int line, int direction)
  21{
  22        unsigned long flags;
  23
  24        local_irq_save(flags);
  25        if (direction == GPIO_IN) {
  26                *IOP3XX_GPOE |= 1 << line;
  27        } else if (direction == GPIO_OUT) {
  28                *IOP3XX_GPOE &= ~(1 << line);
  29        }
  30        local_irq_restore(flags);
  31}
  32EXPORT_SYMBOL(gpio_line_config);
  33
  34int gpio_line_get(int line)
  35{
  36        return !!(*IOP3XX_GPID & (1 << line));
  37}
  38EXPORT_SYMBOL(gpio_line_get);
  39
  40void gpio_line_set(int line, int value)
  41{
  42        unsigned long flags;
  43
  44        local_irq_save(flags);
  45        if (value == GPIO_LOW) {
  46                *IOP3XX_GPOD &= ~(1 << line);
  47        } else if (value == GPIO_HIGH) {
  48                *IOP3XX_GPOD |= 1 << line;
  49        }
  50        local_irq_restore(flags);
  51}
  52EXPORT_SYMBOL(gpio_line_set);
  53
  54static int iop3xx_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
  55{
  56        gpio_line_config(gpio, GPIO_IN);
  57        return 0;
  58}
  59
  60static int iop3xx_gpio_direction_output(struct gpio_chip *chip, unsigned gpio, int level)
  61{
  62        gpio_line_set(gpio, level);
  63        gpio_line_config(gpio, GPIO_OUT);
  64        return 0;
  65}
  66
  67static int iop3xx_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
  68{
  69        return gpio_line_get(gpio);
  70}
  71
  72static void iop3xx_gpio_set_value(struct gpio_chip *chip, unsigned gpio, int value)
  73{
  74        gpio_line_set(gpio, value);
  75}
  76
  77static struct gpio_chip iop3xx_chip = {
  78        .label                  = "iop3xx",
  79        .direction_input        = iop3xx_gpio_direction_input,
  80        .get                    = iop3xx_gpio_get_value,
  81        .direction_output       = iop3xx_gpio_direction_output,
  82        .set                    = iop3xx_gpio_set_value,
  83        .base                   = 0,
  84        .ngpio                  = IOP3XX_N_GPIOS,
  85};
  86
  87static int __init iop3xx_gpio_setup(void)
  88{
  89        return gpiochip_add(&iop3xx_chip);
  90}
  91arch_initcall(iop3xx_gpio_setup);
  92