target/linux/brcm63xx/files/arch/mips/bcm63xx/gpio.c

   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 Florian Fainelli <florian@openwrt.org>
   8  */
   9
  10 #include <linux/kernel.h>
  11 #include <linux/module.h>
  12 #include <linux/spinlock.h>
  13 #include <linux/platform_device.h>
  14 #include <linux/gpio.h>
  15
  16 #include <bcm63xx_cpu.h>
  17 #include <bcm63xx_gpio.h>
  18 #include <bcm63xx_io.h>
  19 #include <bcm63xx_regs.h>
  20
  21 static void bcm63xx_gpio_set(struct gpio_chip *chip,
  22                                 unsigned gpio, int val)
  23 {
  24         u32 reg;
  25         u32 mask;
  26         u32 tmp;
  27         unsigned long flags;
  28
  29         if (gpio >= chip->ngpio)
  30                 BUG();
  31
  32         if (gpio < 32) {
  33                 reg = GPIO_DATA_LO_REG;
  34                 mask = 1 << gpio;
  35         } else {
  36                 reg = GPIO_DATA_HI_REG;
  37                 mask = 1 << (gpio - 32);
  38         }
  39
  40         local_irq_save(flags);
  41         tmp = bcm_gpio_readl(reg);
  42         if (val)
  43                 tmp |= mask;
  44         else
  45                 tmp &= ~mask;
  46         bcm_gpio_writel(tmp, reg);
  47         local_irq_restore(flags);
  48 }
  49
  50 static int bcm63xx_gpio_get(struct gpio_chip *chip, unsigned gpio)
  51 {
  52         u32 reg;
  53         u32 mask;
  54
  55         if (gpio >= chip->ngpio)
  56                 BUG();
  57
  58         if (gpio < 32) {
  59                 reg = GPIO_DATA_LO_REG;
  60                 mask = 1 << gpio;
  61         } else {
  62                 reg = GPIO_DATA_HI_REG;
  63                 mask = 1 << (gpio - 32);
  64         }
  65
  66         return !!(bcm_gpio_readl(reg) & mask);
  67 }
  68
  69 static int bcm63xx_gpio_set_direction(struct gpio_chip *chip,
  70                                         unsigned gpio, int dir)
  71 {
  72         u32 reg;
  73         u32 mask;
  74         u32 tmp;
  75         unsigned long flags;
  76
  77         if (gpio >= chip->ngpio)
  78                 BUG();
  79
  80         if (gpio < 32) {
  81                 reg = GPIO_CTL_LO_REG;
  82                 mask = 1 << gpio;
  83         } else {
  84                 reg = GPIO_CTL_HI_REG;
  85                 mask = 1 << (gpio - 32);
  86         }
  87
  88         local_irq_save(flags);
  89         tmp = bcm_gpio_readl(reg);
  90         if (dir == GPIO_DIR_IN)
  91                 tmp &= ~mask;
  92         else
  93                 tmp |= mask;
  94         bcm_gpio_writel(tmp, reg);
  95         local_irq_restore(flags);
  96
  97         return 0;
  98 }
  99
 100 static int bcm63xx_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
 101 {
 102         return bcm63xx_gpio_set_direction(chip, gpio, GPIO_DIR_IN);
 103 }
 104
 105 static int bcm63xx_gpio_direction_output(struct gpio_chip *chip,
 106                                         unsigned gpio, int value)
 107 {
 108         bcm63xx_gpio_set(chip, gpio, value);
 109         return bcm63xx_gpio_set_direction(chip, gpio, GPIO_DIR_OUT);
 110 }
 111
 112
 113 static struct gpio_chip bcm63xx_gpio_chip = {
 114         .label                  = "bcm63xx-gpio",
 115         .direction_input        = bcm63xx_gpio_direction_input,
 116         .direction_output       = bcm63xx_gpio_direction_output,
 117         .get                    = bcm63xx_gpio_get,
 118         .set                    = bcm63xx_gpio_set,
 119         .base                   = 0,
 120 };
 121
 122 int __init bcm63xx_gpio_init(void)
 123 {
 124         bcm63xx_gpio_chip.ngpio = bcm63xx_gpio_count();
 125         printk(KERN_INFO "registering %d GPIOs\n", bcm63xx_gpio_chip.ngpio);
 126         return gpiochip_add(&bcm63xx_gpio_chip);
 127 }