drivers/gpio/bcm6345_gpio.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2017 Álvaro Fernández Rojas <noltari@gmail.com>
   4  *
   5  * Derived from linux/arch/mips/bcm63xx/gpio.c:
   6  *      Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr>
   7  *      Copyright (C) 2008-2011 Florian Fainelli <florian@openwrt.org>
   8  */
   9
  10 #include <common.h>
  11 #include <dm.h>
  12 #include <errno.h>
  13 #include <asm/gpio.h>
  14 #include <asm/io.h>
  15 #include <linux/bitops.h>
  16
  17 struct bcm6345_gpio_priv {
  18         void __iomem *reg_dirout;
  19         void __iomem *reg_data;
  20 };
  21
  22 static int bcm6345_gpio_get_value(struct udevice *dev, unsigned offset)
  23 {
  24         struct bcm6345_gpio_priv *priv = dev_get_priv(dev);
  25
  26         return !!(readl(priv->reg_data) & BIT(offset));
  27 }
  28
  29 static int bcm6345_gpio_set_value(struct udevice *dev, unsigned offset,
  30                                   int value)
  31 {
  32         struct bcm6345_gpio_priv *priv = dev_get_priv(dev);
  33
  34         if (value)
  35                 setbits_32(priv->reg_data, BIT(offset));
  36         else
  37                 clrbits_32(priv->reg_data, BIT(offset));
  38
  39         return 0;
  40 }
  41
  42 static int bcm6345_gpio_set_direction(void __iomem *dirout, unsigned offset,
  43                                       bool input)
  44 {
  45         if (input)
  46                 clrbits_32(dirout, BIT(offset));
  47         else
  48                 setbits_32(dirout, BIT(offset));
  49
  50         return 0;
  51 }
  52
  53 static int bcm6345_gpio_direction_input(struct udevice *dev, unsigned offset)
  54 {
  55         struct bcm6345_gpio_priv *priv = dev_get_priv(dev);
  56
  57         return bcm6345_gpio_set_direction(priv->reg_dirout, offset, 1);
  58 }
  59
  60 static int bcm6345_gpio_direction_output(struct udevice *dev, unsigned offset,
  61                                          int value)
  62 {
  63         struct bcm6345_gpio_priv *priv = dev_get_priv(dev);
  64
  65         bcm6345_gpio_set_value(dev, offset, value);
  66
  67         return bcm6345_gpio_set_direction(priv->reg_dirout, offset, 0);
  68 }
  69
  70 static int bcm6345_gpio_get_function(struct udevice *dev, unsigned offset)
  71 {
  72         struct bcm6345_gpio_priv *priv = dev_get_priv(dev);
  73
  74         if (readl(priv->reg_dirout) & BIT(offset))
  75                 return GPIOF_OUTPUT;
  76         else
  77                 return GPIOF_INPUT;
  78 }
  79
  80 static const struct dm_gpio_ops bcm6345_gpio_ops = {
  81         .direction_input = bcm6345_gpio_direction_input,
  82         .direction_output = bcm6345_gpio_direction_output,
  83         .get_value = bcm6345_gpio_get_value,
  84         .set_value = bcm6345_gpio_set_value,
  85         .get_function = bcm6345_gpio_get_function,
  86 };
  87
  88 static int bcm6345_gpio_probe(struct udevice *dev)
  89 {
  90         struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
  91         struct bcm6345_gpio_priv *priv = dev_get_priv(dev);
  92
  93         priv->reg_dirout = dev_remap_addr_index(dev, 0);
  94         if (!priv->reg_dirout)
  95                 return -EINVAL;
  96
  97         priv->reg_data = dev_remap_addr_index(dev, 1);
  98         if (!priv->reg_data)
  99                 return -EINVAL;
 100
 101         uc_priv->gpio_count = dev_read_u32_default(dev, "ngpios", 32);
 102         uc_priv->bank_name = dev->name;
 103
 104         return 0;
 105 }
 106
 107 static const struct udevice_id bcm6345_gpio_ids[] = {
 108         { .compatible = "brcm,bcm6345-gpio" },
 109         { /* sentinel */ }
 110 };
 111
 112 U_BOOT_DRIVER(bcm6345_gpio) = {
 113         .name = "bcm6345-gpio",
 114         .id = UCLASS_GPIO,
 115         .of_match = bcm6345_gpio_ids,
 116         .ops = &bcm6345_gpio_ops,
 117         .priv_auto      = sizeof(struct bcm6345_gpio_priv),
 118         .probe = bcm6345_gpio_probe,
 119 };