linux/arch/mips/bcm63xx/gpio.c
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   1/*
   2 * This file is subject to the terms and conditions of the GNU General Public
   3 * License.  See the file "COPYING" in the main directory of this archive
   4 * for more details.
   5 *
   6 * Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr>
   7 * Copyright (C) 2008-2011 Florian Fainelli <florian@openwrt.org>
   8 */
   9
  10#include <linux/kernel.h>
  11#include <linux/init.h>
  12#include <linux/spinlock.h>
  13#include <linux/platform_device.h>
  14#include <linux/gpio/driver.h>
  15
  16#include <bcm63xx_cpu.h>
  17#include <bcm63xx_gpio.h>
  18#include <bcm63xx_io.h>
  19#include <bcm63xx_regs.h>
  20
  21static u32 gpio_out_low_reg;
  22
  23static void bcm63xx_gpio_out_low_reg_init(void)
  24{
  25        switch (bcm63xx_get_cpu_id()) {
  26        case BCM6345_CPU_ID:
  27                gpio_out_low_reg = GPIO_DATA_LO_REG_6345;
  28                break;
  29        default:
  30                gpio_out_low_reg = GPIO_DATA_LO_REG;
  31                break;
  32        }
  33}
  34
  35static DEFINE_SPINLOCK(bcm63xx_gpio_lock);
  36static u32 gpio_out_low, gpio_out_high;
  37
  38static void bcm63xx_gpio_set(struct gpio_chip *chip,
  39                             unsigned gpio, int val)
  40{
  41        u32 reg;
  42        u32 mask;
  43        u32 *v;
  44        unsigned long flags;
  45
  46        BUG_ON(gpio >= chip->ngpio);
  47
  48        if (gpio < 32) {
  49                reg = gpio_out_low_reg;
  50                mask = 1 << gpio;
  51                v = &gpio_out_low;
  52        } else {
  53                reg = GPIO_DATA_HI_REG;
  54                mask = 1 << (gpio - 32);
  55                v = &gpio_out_high;
  56        }
  57
  58        spin_lock_irqsave(&bcm63xx_gpio_lock, flags);
  59        if (val)
  60                *v |= mask;
  61        else
  62                *v &= ~mask;
  63        bcm_gpio_writel(*v, reg);
  64        spin_unlock_irqrestore(&bcm63xx_gpio_lock, flags);
  65}
  66
  67static int bcm63xx_gpio_get(struct gpio_chip *chip, unsigned gpio)
  68{
  69        u32 reg;
  70        u32 mask;
  71
  72        BUG_ON(gpio >= chip->ngpio);
  73
  74        if (gpio < 32) {
  75                reg = gpio_out_low_reg;
  76                mask = 1 << gpio;
  77        } else {
  78                reg = GPIO_DATA_HI_REG;
  79                mask = 1 << (gpio - 32);
  80        }
  81
  82        return !!(bcm_gpio_readl(reg) & mask);
  83}
  84
  85static int bcm63xx_gpio_set_direction(struct gpio_chip *chip,
  86                                      unsigned gpio, int dir)
  87{
  88        u32 reg;
  89        u32 mask;
  90        u32 tmp;
  91        unsigned long flags;
  92
  93        BUG_ON(gpio >= chip->ngpio);
  94
  95        if (gpio < 32) {
  96                reg = GPIO_CTL_LO_REG;
  97                mask = 1 << gpio;
  98        } else {
  99                reg = GPIO_CTL_HI_REG;
 100                mask = 1 << (gpio - 32);
 101        }
 102
 103        spin_lock_irqsave(&bcm63xx_gpio_lock, flags);
 104        tmp = bcm_gpio_readl(reg);
 105        if (dir == BCM63XX_GPIO_DIR_IN)
 106                tmp &= ~mask;
 107        else
 108                tmp |= mask;
 109        bcm_gpio_writel(tmp, reg);
 110        spin_unlock_irqrestore(&bcm63xx_gpio_lock, flags);
 111
 112        return 0;
 113}
 114
 115static int bcm63xx_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
 116{
 117        return bcm63xx_gpio_set_direction(chip, gpio, BCM63XX_GPIO_DIR_IN);
 118}
 119
 120static int bcm63xx_gpio_direction_output(struct gpio_chip *chip,
 121                                         unsigned gpio, int value)
 122{
 123        bcm63xx_gpio_set(chip, gpio, value);
 124        return bcm63xx_gpio_set_direction(chip, gpio, BCM63XX_GPIO_DIR_OUT);
 125}
 126
 127
 128static struct gpio_chip bcm63xx_gpio_chip = {
 129        .label                  = "bcm63xx-gpio",
 130        .direction_input        = bcm63xx_gpio_direction_input,
 131        .direction_output       = bcm63xx_gpio_direction_output,
 132        .get                    = bcm63xx_gpio_get,
 133        .set                    = bcm63xx_gpio_set,
 134        .base                   = 0,
 135};
 136
 137int __init bcm63xx_gpio_init(void)
 138{
 139        bcm63xx_gpio_out_low_reg_init();
 140
 141        gpio_out_low = bcm_gpio_readl(gpio_out_low_reg);
 142        if (!BCMCPU_IS_6345())
 143                gpio_out_high = bcm_gpio_readl(GPIO_DATA_HI_REG);
 144        bcm63xx_gpio_chip.ngpio = bcm63xx_gpio_count();
 145        pr_info("registering %d GPIOs\n", bcm63xx_gpio_chip.ngpio);
 146
 147        return gpiochip_add_data(&bcm63xx_gpio_chip, NULL);
 148}
 149