drivers/gpio/spear_gpio.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2012 Stefan Roese <sr@denx.de>
   4  */
   5
   6 /*
   7  * Driver for SPEAr600 GPIO controller
   8  */
   9
  10 #include <common.h>
  11 #include <asm/arch/hardware.h>
  12 #include <asm/gpio.h>
  13 #include <asm/io.h>
  14 #include <errno.h>
  15
  16 static int gpio_direction(unsigned gpio,
  17                           enum gpio_direction direction)
  18 {
  19         struct gpio_regs *regs = (struct gpio_regs *)CONFIG_GPIO_BASE;
  20         u32 val;
  21
  22         val = readl(&regs->gpiodir);
  23
  24         if (direction == GPIO_DIRECTION_OUT)
  25                 val |= 1 << gpio;
  26         else
  27                 val &= ~(1 << gpio);
  28
  29         writel(val, &regs->gpiodir);
  30
  31         return 0;
  32 }
  33
  34 int gpio_set_value(unsigned gpio, int value)
  35 {
  36         struct gpio_regs *regs = (struct gpio_regs *)CONFIG_GPIO_BASE;
  37
  38         if (value)
  39                 writel(1 << gpio, &regs->gpiodata[DATA_REG_ADDR(gpio)]);
  40         else
  41                 writel(0, &regs->gpiodata[DATA_REG_ADDR(gpio)]);
  42
  43         return 0;
  44 }
  45
  46 int gpio_get_value(unsigned gpio)
  47 {
  48         struct gpio_regs *regs = (struct gpio_regs *)CONFIG_GPIO_BASE;
  49         u32 val;
  50
  51         val = readl(&regs->gpiodata[DATA_REG_ADDR(gpio)]);
  52
  53         return !!val;
  54 }
  55
  56 int gpio_request(unsigned gpio, const char *label)
  57 {
  58         if (gpio >= SPEAR_GPIO_COUNT)
  59                 return -EINVAL;
  60
  61         return 0;
  62 }
  63
  64 int gpio_free(unsigned gpio)
  65 {
  66         return 0;
  67 }
  68
  69 void gpio_toggle_value(unsigned gpio)
  70 {
  71         gpio_set_value(gpio, !gpio_get_value(gpio));
  72 }
  73
  74 int gpio_direction_input(unsigned gpio)
  75 {
  76         return gpio_direction(gpio, GPIO_DIRECTION_IN);
  77 }
  78
  79 int gpio_direction_output(unsigned gpio, int value)
  80 {
  81         int ret = gpio_direction(gpio, GPIO_DIRECTION_OUT);
  82
  83         if (ret < 0)
  84                 return ret;
  85
  86         gpio_set_value(gpio, value);
  87         return 0;
  88 }