linux/arch/mips/ath79/gpio.c
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   1/*
   2 *  Atheros AR71XX/AR724X/AR913X GPIO API support
   3 *
   4 *  Copyright (C) 2008-2010 Gabor Juhos <juhosg@openwrt.org>
   5 *  Copyright (C) 2008 Imre Kaloz <kaloz@openwrt.org>
   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
   9 *  by the Free Software Foundation.
  10 */
  11
  12#include <linux/kernel.h>
  13#include <linux/init.h>
  14#include <linux/module.h>
  15#include <linux/types.h>
  16#include <linux/spinlock.h>
  17#include <linux/io.h>
  18#include <linux/ioport.h>
  19#include <linux/gpio.h>
  20
  21#include <asm/mach-ath79/ar71xx_regs.h>
  22#include <asm/mach-ath79/ath79.h>
  23#include "common.h"
  24
  25static void __iomem *ath79_gpio_base;
  26static unsigned long ath79_gpio_count;
  27static DEFINE_SPINLOCK(ath79_gpio_lock);
  28
  29static void __ath79_gpio_set_value(unsigned gpio, int value)
  30{
  31        void __iomem *base = ath79_gpio_base;
  32
  33        if (value)
  34                __raw_writel(1 << gpio, base + AR71XX_GPIO_REG_SET);
  35        else
  36                __raw_writel(1 << gpio, base + AR71XX_GPIO_REG_CLEAR);
  37}
  38
  39static int __ath79_gpio_get_value(unsigned gpio)
  40{
  41        return (__raw_readl(ath79_gpio_base + AR71XX_GPIO_REG_IN) >> gpio) & 1;
  42}
  43
  44static int ath79_gpio_get_value(struct gpio_chip *chip, unsigned offset)
  45{
  46        return __ath79_gpio_get_value(offset);
  47}
  48
  49static void ath79_gpio_set_value(struct gpio_chip *chip,
  50                                  unsigned offset, int value)
  51{
  52        __ath79_gpio_set_value(offset, value);
  53}
  54
  55static int ath79_gpio_direction_input(struct gpio_chip *chip,
  56                                       unsigned offset)
  57{
  58        void __iomem *base = ath79_gpio_base;
  59        unsigned long flags;
  60
  61        spin_lock_irqsave(&ath79_gpio_lock, flags);
  62
  63        __raw_writel(__raw_readl(base + AR71XX_GPIO_REG_OE) & ~(1 << offset),
  64                     base + AR71XX_GPIO_REG_OE);
  65
  66        spin_unlock_irqrestore(&ath79_gpio_lock, flags);
  67
  68        return 0;
  69}
  70
  71static int ath79_gpio_direction_output(struct gpio_chip *chip,
  72                                        unsigned offset, int value)
  73{
  74        void __iomem *base = ath79_gpio_base;
  75        unsigned long flags;
  76
  77        spin_lock_irqsave(&ath79_gpio_lock, flags);
  78
  79        if (value)
  80                __raw_writel(1 << offset, base + AR71XX_GPIO_REG_SET);
  81        else
  82                __raw_writel(1 << offset, base + AR71XX_GPIO_REG_CLEAR);
  83
  84        __raw_writel(__raw_readl(base + AR71XX_GPIO_REG_OE) | (1 << offset),
  85                     base + AR71XX_GPIO_REG_OE);
  86
  87        spin_unlock_irqrestore(&ath79_gpio_lock, flags);
  88
  89        return 0;
  90}
  91
  92static struct gpio_chip ath79_gpio_chip = {
  93        .label                  = "ath79",
  94        .get                    = ath79_gpio_get_value,
  95        .set                    = ath79_gpio_set_value,
  96        .direction_input        = ath79_gpio_direction_input,
  97        .direction_output       = ath79_gpio_direction_output,
  98        .base                   = 0,
  99};
 100
 101void ath79_gpio_function_enable(u32 mask)
 102{
 103        void __iomem *base = ath79_gpio_base;
 104        unsigned long flags;
 105
 106        spin_lock_irqsave(&ath79_gpio_lock, flags);
 107
 108        __raw_writel(__raw_readl(base + AR71XX_GPIO_REG_FUNC) | mask,
 109                     base + AR71XX_GPIO_REG_FUNC);
 110        /* flush write */
 111        __raw_readl(base + AR71XX_GPIO_REG_FUNC);
 112
 113        spin_unlock_irqrestore(&ath79_gpio_lock, flags);
 114}
 115
 116void ath79_gpio_function_disable(u32 mask)
 117{
 118        void __iomem *base = ath79_gpio_base;
 119        unsigned long flags;
 120
 121        spin_lock_irqsave(&ath79_gpio_lock, flags);
 122
 123        __raw_writel(__raw_readl(base + AR71XX_GPIO_REG_FUNC) & ~mask,
 124                     base + AR71XX_GPIO_REG_FUNC);
 125        /* flush write */
 126        __raw_readl(base + AR71XX_GPIO_REG_FUNC);
 127
 128        spin_unlock_irqrestore(&ath79_gpio_lock, flags);
 129}
 130
 131void ath79_gpio_function_setup(u32 set, u32 clear)
 132{
 133        void __iomem *base = ath79_gpio_base;
 134        unsigned long flags;
 135
 136        spin_lock_irqsave(&ath79_gpio_lock, flags);
 137
 138        __raw_writel((__raw_readl(base + AR71XX_GPIO_REG_FUNC) & ~clear) | set,
 139                     base + AR71XX_GPIO_REG_FUNC);
 140        /* flush write */
 141        __raw_readl(base + AR71XX_GPIO_REG_FUNC);
 142
 143        spin_unlock_irqrestore(&ath79_gpio_lock, flags);
 144}
 145
 146void __init ath79_gpio_init(void)
 147{
 148        int err;
 149
 150        if (soc_is_ar71xx())
 151                ath79_gpio_count = AR71XX_GPIO_COUNT;
 152        else if (soc_is_ar724x())
 153                ath79_gpio_count = AR724X_GPIO_COUNT;
 154        else if (soc_is_ar913x())
 155                ath79_gpio_count = AR913X_GPIO_COUNT;
 156        else
 157                BUG();
 158
 159        ath79_gpio_base = ioremap_nocache(AR71XX_GPIO_BASE, AR71XX_GPIO_SIZE);
 160        ath79_gpio_chip.ngpio = ath79_gpio_count;
 161
 162        err = gpiochip_add(&ath79_gpio_chip);
 163        if (err)
 164                panic("cannot add AR71xx GPIO chip, error=%d", err);
 165}
 166
 167int gpio_get_value(unsigned gpio)
 168{
 169        if (gpio < ath79_gpio_count)
 170                return __ath79_gpio_get_value(gpio);
 171
 172        return __gpio_get_value(gpio);
 173}
 174EXPORT_SYMBOL(gpio_get_value);
 175
 176void gpio_set_value(unsigned gpio, int value)
 177{
 178        if (gpio < ath79_gpio_count)
 179                __ath79_gpio_set_value(gpio, value);
 180        else
 181                __gpio_set_value(gpio, value);
 182}
 183EXPORT_SYMBOL(gpio_set_value);
 184
 185int gpio_to_irq(unsigned gpio)
 186{
 187        /* FIXME */
 188        return -EINVAL;
 189}
 190EXPORT_SYMBOL(gpio_to_irq);
 191
 192int irq_to_gpio(unsigned irq)
 193{
 194        /* FIXME */
 195        return -EINVAL;
 196}
 197EXPORT_SYMBOL(irq_to_gpio);
 198