target/linux/ar71xx/files/arch/mips/ar71xx/gpio.c

   1 /*
   2  *  Atheros AR71xx SoC GPIO API support
   3  *
   4  *  Copyright (C) 2008 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-ar71xx/ar71xx.h>
  22
  23 static DEFINE_SPINLOCK(ar71xx_gpio_lock);
  24
  25 unsigned long ar71xx_gpio_count;
  26 EXPORT_SYMBOL(ar71xx_gpio_count);
  27
  28 void __ar71xx_gpio_set_value(unsigned gpio, int value)
  29 {
  30         unsigned long flags;
  31
  32         spin_lock_irqsave(&ar71xx_gpio_lock, flags);
  33
  34         if (value)
  35                 ar71xx_gpio_wr(GPIO_REG_SET, (1 << gpio));
  36         else
  37                 ar71xx_gpio_wr(GPIO_REG_CLEAR, (1 << gpio));
  38
  39         spin_unlock_irqrestore(&ar71xx_gpio_lock, flags);
  40 }
  41 EXPORT_SYMBOL(__ar71xx_gpio_set_value);
  42
  43 int __ar71xx_gpio_get_value(unsigned gpio)
  44 {
  45         return (ar71xx_gpio_rr(GPIO_REG_IN) & (1 << gpio)) ? 1 : 0;
  46 }
  47 EXPORT_SYMBOL(__ar71xx_gpio_get_value);
  48
  49 static int ar71xx_gpio_get_value(struct gpio_chip *chip, unsigned offset)
  50 {
  51         return __ar71xx_gpio_get_value(offset);
  52 }
  53
  54 static void ar71xx_gpio_set_value(struct gpio_chip *chip,
  55                                   unsigned offset, int value)
  56 {
  57         __ar71xx_gpio_set_value(offset, value);
  58 }
  59
  60 static int ar71xx_gpio_direction_input(struct gpio_chip *chip,
  61                                        unsigned offset)
  62 {
  63         unsigned long flags;
  64
  65         spin_lock_irqsave(&ar71xx_gpio_lock, flags);
  66
  67         ar71xx_gpio_wr(GPIO_REG_OE,
  68                         ar71xx_gpio_rr(GPIO_REG_OE) & ~(1 << offset));
  69
  70         spin_unlock_irqrestore(&ar71xx_gpio_lock, flags);
  71
  72         return 0;
  73 }
  74
  75 static int ar71xx_gpio_direction_output(struct gpio_chip *chip,
  76                                         unsigned offset, int value)
  77 {
  78         unsigned long flags;
  79
  80         spin_lock_irqsave(&ar71xx_gpio_lock, flags);
  81
  82         if (value)
  83                 ar71xx_gpio_wr(GPIO_REG_SET, (1 << offset));
  84         else
  85                 ar71xx_gpio_wr(GPIO_REG_CLEAR, (1 << offset));
  86
  87         ar71xx_gpio_wr(GPIO_REG_OE,
  88                         ar71xx_gpio_rr(GPIO_REG_OE) | (1 << offset));
  89
  90         spin_unlock_irqrestore(&ar71xx_gpio_lock, flags);
  91
  92         return 0;
  93 }
  94
  95 static struct gpio_chip ar71xx_gpio_chip = {
  96         .label                  = "ar71xx",
  97         .get                    = ar71xx_gpio_get_value,
  98         .set                    = ar71xx_gpio_set_value,
  99         .direction_input        = ar71xx_gpio_direction_input,
 100         .direction_output       = ar71xx_gpio_direction_output,
 101         .base                   = 0,
 102         .ngpio                  = AR71XX_GPIO_COUNT,
 103 };
 104
 105 void ar71xx_gpio_function_enable(u32 mask)
 106 {
 107         unsigned long flags;
 108
 109         spin_lock_irqsave(&ar71xx_gpio_lock, flags);
 110
 111         ar71xx_gpio_wr(GPIO_REG_FUNC, ar71xx_gpio_rr(GPIO_REG_FUNC) | mask);
 112
 113         spin_unlock_irqrestore(&ar71xx_gpio_lock, flags);
 114 }
 115
 116 void ar71xx_gpio_function_disable(u32 mask)
 117 {
 118         unsigned long flags;
 119
 120         spin_lock_irqsave(&ar71xx_gpio_lock, flags);
 121
 122         ar71xx_gpio_wr(GPIO_REG_FUNC, ar71xx_gpio_rr(GPIO_REG_FUNC) & ~mask);
 123
 124         spin_unlock_irqrestore(&ar71xx_gpio_lock, flags);
 125 }
 126
 127 void __init ar71xx_gpio_init(void)
 128 {
 129         int err;
 130
 131         if (!request_mem_region(AR71XX_GPIO_BASE, AR71XX_GPIO_SIZE,
 132                                 "AR71xx GPIO controller"))
 133                 panic("cannot allocate AR71xx GPIO registers page");
 134
 135         switch (ar71xx_soc) {
 136         case AR71XX_SOC_AR7130:
 137         case AR71XX_SOC_AR7141:
 138         case AR71XX_SOC_AR7161:
 139                 ar71xx_gpio_chip.ngpio = AR71XX_GPIO_COUNT;
 140                 break;
 141
 142         case AR71XX_SOC_AR9130:
 143         case AR71XX_SOC_AR9132:
 144                 ar71xx_gpio_chip.ngpio = AR91XX_GPIO_COUNT;
 145                 break;
 146
 147         default:
 148                 BUG();
 149         }
 150
 151         err = gpiochip_add(&ar71xx_gpio_chip);
 152         if (err)
 153                 panic("cannot add AR71xx GPIO chip, error=%d", err);
 154 }