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 u32 gpio_out_low, gpio_out_high;
  22
  23 static void bcm63xx_gpio_set(struct gpio_chip *chip,
  24                                 unsigned gpio, int val)
  25 {
  26         u32 reg;
  27         u32 mask;
  28         u32 *v;
  29         unsigned long flags;
  30
  31         if (gpio >= chip->ngpio)
  32                 BUG();
  33
  34         if (gpio < 32) {
  35                 reg = GPIO_DATA_LO_REG;
  36                 mask = 1 << gpio;
  37                 v = &gpio_out_low;
  38         } else {
  39                 reg = GPIO_DATA_HI_REG;
  40                 mask = 1 << (gpio - 32);
  41                 v = &gpio_out_high;
  42         }
  43
  44         local_irq_save(flags);
  45         if (val)
  46                 *v |= mask;
  47         else
  48                 *v &= ~mask;
  49         bcm_gpio_writel(*v, reg);
  50         local_irq_restore(flags);
  51 }
  52
  53 static int bcm63xx_gpio_get(struct gpio_chip *chip, unsigned gpio)
  54 {
  55         u32 reg;
  56         u32 mask;
  57
  58         if (gpio >= chip->ngpio)
  59                 BUG();
  60
  61         if (gpio < 32) {
  62                 reg = GPIO_DATA_LO_REG;
  63                 mask = 1 << gpio;
  64         } else {
  65                 reg = GPIO_DATA_HI_REG;
  66                 mask = 1 << (gpio - 32);
  67         }
  68
  69         return !!(bcm_gpio_readl(reg) & mask);
  70 }
  71
  72 static int bcm63xx_gpio_set_direction(struct gpio_chip *chip,
  73                                         unsigned gpio, int dir)
  74 {
  75         u32 reg;
  76         u32 mask;
  77         u32 tmp;
  78         unsigned long flags;
  79
  80         if (gpio >= chip->ngpio)
  81                 BUG();
  82
  83         if (gpio < 32) {
  84                 reg = GPIO_CTL_LO_REG;
  85                 mask = 1 << gpio;
  86         } else {
  87                 reg = GPIO_CTL_HI_REG;
  88                 mask = 1 << (gpio - 32);
  89         }
  90
  91         local_irq_save(flags);
  92         tmp = bcm_gpio_readl(reg);
  93         if (dir == GPIO_DIR_IN)
  94                 tmp &= ~mask;
  95         else
  96                 tmp |= mask;
  97         bcm_gpio_writel(tmp, reg);
  98         local_irq_restore(flags);
  99
 100         return 0;
 101 }
 102
 103 static int bcm63xx_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
 104 {
 105         return bcm63xx_gpio_set_direction(chip, gpio, GPIO_DIR_IN);
 106 }
 107
 108 static int bcm63xx_gpio_direction_output(struct gpio_chip *chip,
 109                                         unsigned gpio, int value)
 110 {
 111         bcm63xx_gpio_set(chip, gpio, value);
 112         return bcm63xx_gpio_set_direction(chip, gpio, GPIO_DIR_OUT);
 113 }
 114
 115
 116 static struct gpio_chip bcm63xx_gpio_chip = {
 117         .label                  = "bcm63xx-gpio",
 118         .direction_input        = bcm63xx_gpio_direction_input,
 119         .direction_output       = bcm63xx_gpio_direction_output,
 120         .get                    = bcm63xx_gpio_get,
 121         .set                    = bcm63xx_gpio_set,
 122         .base                   = 0,
 123 };
 124
 125 int __init bcm63xx_gpio_init(void)
 126 {
 127         bcm63xx_gpio_chip.ngpio = bcm63xx_gpio_count();
 128         printk(KERN_INFO "registering %d GPIOs\n", bcm63xx_gpio_chip.ngpio);
 129         return gpiochip_add(&bcm63xx_gpio_chip);
 130 }