LXR linux/arch/arm/mach-ns9xxx/gpio.c

   1/*
   2 * arch/arm/mach-ns9xxx/gpio.c
   3 *
   4 * Copyright (C) 2006,2007 by Digi International Inc.
   5 * All rights reserved.
   6 *
   7 * This program is free software; you can redistribute it and/or modify it
   8 * under the terms of the GNU General Public License version 2 as published by
   9 * the Free Software Foundation.
  10 */
  11#include <linux/kernel.h>
  12#include <linux/compiler.h>
  13#include <linux/init.h>
  14#include <linux/spinlock.h>
  15#include <linux/module.h>
  16#include <linux/bitops.h>
  17
  18#include <mach/gpio.h>
  19#include <mach/processor.h>
  20#include <mach/processor-ns9360.h>
  21#include <asm/bug.h>
  22#include <asm/types.h>
  23
  24#include "gpio-ns9360.h"
  25
  26#if defined(CONFIG_PROCESSOR_NS9360)
  27#define GPIO_MAX 72
  28#elif defined(CONFIG_PROCESSOR_NS9750)
  29#define GPIO_MAX 49
  30#endif
  31
  32/* protects BBU_GCONFx and BBU_GCTRLx */
  33static spinlock_t gpio_lock = __SPIN_LOCK_UNLOCKED(gpio_lock);
  34
  35/* only access gpiores with atomic ops */
  36static DECLARE_BITMAP(gpiores, GPIO_MAX + 1);
  37
  38static inline int ns9xxx_valid_gpio(unsigned gpio)
  39{
  40#if defined(CONFIG_PROCESSOR_NS9360)
  41        if (processor_is_ns9360())
  42                return gpio <= 72;
  43        else
  44#endif
  45#if defined(CONFIG_PROCESSOR_NS9750)
  46        if (processor_is_ns9750())
  47                return gpio <= 49;
  48        else
  49#endif
  50        {
  51                BUG();
  52                return 0;
  53        }
  54}
  55
  56int gpio_request(unsigned gpio, const char *label)
  57{
  58        if (likely(ns9xxx_valid_gpio(gpio)))
  59                return test_and_set_bit(gpio, gpiores) ? -EBUSY : 0;
  60        else
  61                return -EINVAL;
  62}
  63EXPORT_SYMBOL(gpio_request);
  64
  65void gpio_free(unsigned gpio)
  66{
  67        might_sleep();
  68        clear_bit(gpio, gpiores);
  69        return;
  70}
  71EXPORT_SYMBOL(gpio_free);
  72
  73int gpio_direction_input(unsigned gpio)
  74{
  75        if (likely(ns9xxx_valid_gpio(gpio))) {
  76                int ret = -EINVAL;
  77                unsigned long flags;
  78
  79                spin_lock_irqsave(&gpio_lock, flags);
  80#if defined(CONFIG_PROCESSOR_NS9360)
  81                if (processor_is_ns9360())
  82                        ret = __ns9360_gpio_configure(gpio, 0, 0, 3);
  83                else
  84#endif
  85                        BUG();
  86
  87                spin_unlock_irqrestore(&gpio_lock, flags);
  88
  89                return ret;
  90
  91        } else
  92                return -EINVAL;
  93}
  94EXPORT_SYMBOL(gpio_direction_input);
  95
  96int gpio_direction_output(unsigned gpio, int value)
  97{
  98        if (likely(ns9xxx_valid_gpio(gpio))) {
  99                int ret = -EINVAL;
 100                unsigned long flags;
 101
 102                gpio_set_value(gpio, value);
 103
 104                spin_lock_irqsave(&gpio_lock, flags);
 105#if defined(CONFIG_PROCESSOR_NS9360)
 106                if (processor_is_ns9360())
 107                        ret = __ns9360_gpio_configure(gpio, 1, 0, 3);
 108                else
 109#endif
 110                        BUG();
 111
 112                spin_unlock_irqrestore(&gpio_lock, flags);
 113
 114                return ret;
 115        } else
 116                return -EINVAL;
 117}
 118EXPORT_SYMBOL(gpio_direction_output);
 119
 120int gpio_get_value(unsigned gpio)
 121{
 122#if defined(CONFIG_PROCESSOR_NS9360)
 123        if (processor_is_ns9360())
 124                return ns9360_gpio_get_value(gpio);
 125        else
 126#endif
 127        {
 128                BUG();
 129                return -EINVAL;
 130        }
 131}
 132EXPORT_SYMBOL(gpio_get_value);
 133
 134void gpio_set_value(unsigned gpio, int value)
 135{
 136        unsigned long flags;
 137        spin_lock_irqsave(&gpio_lock, flags);
 138#if defined(CONFIG_PROCESSOR_NS9360)
 139        if (processor_is_ns9360())
 140                ns9360_gpio_set_value(gpio, value);
 141        else
 142#endif
 143                BUG();
 144
 145        spin_unlock_irqrestore(&gpio_lock, flags);
 146}
 147EXPORT_SYMBOL(gpio_set_value);
 148