drivers/gpio/gpio-clps711x.c

   1 /*
   2  *  CLPS711X GPIO driver
   3  *
   4  *  Copyright (C) 2012 Alexander Shiyan <shc_work@mail.ru>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  */
  11
  12 #include <linux/io.h>
  13 #include <linux/slab.h>
  14 #include <linux/gpio.h>
  15 #include <linux/module.h>
  16 #include <linux/spinlock.h>
  17 #include <linux/platform_device.h>
  18
  19 #include <mach/hardware.h>
  20
  21 #define CLPS711X_GPIO_PORTS     5
  22 #define CLPS711X_GPIO_NAME      "gpio-clps711x"
  23
  24 struct clps711x_gpio {
  25         struct gpio_chip        chip[CLPS711X_GPIO_PORTS];
  26         spinlock_t              lock;
  27 };
  28
  29 static void __iomem *clps711x_ports[] = {
  30         CLPS711X_VIRT_BASE + PADR,
  31         CLPS711X_VIRT_BASE + PBDR,
  32         CLPS711X_VIRT_BASE + PCDR,
  33         CLPS711X_VIRT_BASE + PDDR,
  34         CLPS711X_VIRT_BASE + PEDR,
  35 };
  36
  37 static void __iomem *clps711x_pdirs[] = {
  38         CLPS711X_VIRT_BASE + PADDR,
  39         CLPS711X_VIRT_BASE + PBDDR,
  40         CLPS711X_VIRT_BASE + PCDDR,
  41         CLPS711X_VIRT_BASE + PDDDR,
  42         CLPS711X_VIRT_BASE + PEDDR,
  43 };
  44
  45 #define clps711x_port(x)        clps711x_ports[x->base / 8]
  46 #define clps711x_pdir(x)        clps711x_pdirs[x->base / 8]
  47
  48 static int gpio_clps711x_get(struct gpio_chip *chip, unsigned offset)
  49 {
  50         return !!(readb(clps711x_port(chip)) & (1 << offset));
  51 }
  52
  53 static void gpio_clps711x_set(struct gpio_chip *chip, unsigned offset,
  54                               int value)
  55 {
  56         int tmp;
  57         unsigned long flags;
  58         struct clps711x_gpio *gpio = dev_get_drvdata(chip->dev);
  59
  60         spin_lock_irqsave(&gpio->lock, flags);
  61         tmp = readb(clps711x_port(chip)) & ~(1 << offset);
  62         if (value)
  63                 tmp |= 1 << offset;
  64         writeb(tmp, clps711x_port(chip));
  65         spin_unlock_irqrestore(&gpio->lock, flags);
  66 }
  67
  68 static int gpio_clps711x_dir_in(struct gpio_chip *chip, unsigned offset)
  69 {
  70         int tmp;
  71         unsigned long flags;
  72         struct clps711x_gpio *gpio = dev_get_drvdata(chip->dev);
  73
  74         spin_lock_irqsave(&gpio->lock, flags);
  75         tmp = readb(clps711x_pdir(chip)) & ~(1 << offset);
  76         writeb(tmp, clps711x_pdir(chip));
  77         spin_unlock_irqrestore(&gpio->lock, flags);
  78
  79         return 0;
  80 }
  81
  82 static int gpio_clps711x_dir_out(struct gpio_chip *chip, unsigned offset,
  83                                  int value)
  84 {
  85         int tmp;
  86         unsigned long flags;
  87         struct clps711x_gpio *gpio = dev_get_drvdata(chip->dev);
  88
  89         spin_lock_irqsave(&gpio->lock, flags);
  90         tmp = readb(clps711x_pdir(chip)) | (1 << offset);
  91         writeb(tmp, clps711x_pdir(chip));
  92         tmp = readb(clps711x_port(chip)) & ~(1 << offset);
  93         if (value)
  94                 tmp |= 1 << offset;
  95         writeb(tmp, clps711x_port(chip));
  96         spin_unlock_irqrestore(&gpio->lock, flags);
  97
  98         return 0;
  99 }
 100
 101 static int gpio_clps711x_dir_in_inv(struct gpio_chip *chip, unsigned offset)
 102 {
 103         int tmp;
 104         unsigned long flags;
 105         struct clps711x_gpio *gpio = dev_get_drvdata(chip->dev);
 106
 107         spin_lock_irqsave(&gpio->lock, flags);
 108         tmp = readb(clps711x_pdir(chip)) | (1 << offset);
 109         writeb(tmp, clps711x_pdir(chip));
 110         spin_unlock_irqrestore(&gpio->lock, flags);
 111
 112         return 0;
 113 }
 114
 115 static int gpio_clps711x_dir_out_inv(struct gpio_chip *chip, unsigned offset,
 116                                      int value)
 117 {
 118         int tmp;
 119         unsigned long flags;
 120         struct clps711x_gpio *gpio = dev_get_drvdata(chip->dev);
 121
 122         spin_lock_irqsave(&gpio->lock, flags);
 123         tmp = readb(clps711x_pdir(chip)) & ~(1 << offset);
 124         writeb(tmp, clps711x_pdir(chip));
 125         tmp = readb(clps711x_port(chip)) & ~(1 << offset);
 126         if (value)
 127                 tmp |= 1 << offset;
 128         writeb(tmp, clps711x_port(chip));
 129         spin_unlock_irqrestore(&gpio->lock, flags);
 130
 131         return 0;
 132 }
 133
 134 static struct {
 135         char    *name;
 136         int     nr;
 137         int     inv_dir;
 138 } clps711x_gpio_ports[] __initconst = {
 139         { "PORTA", 8, 0, },
 140         { "PORTB", 8, 0, },
 141         { "PORTC", 8, 0, },
 142         { "PORTD", 8, 1, },
 143         { "PORTE", 3, 0, },
 144 };
 145
 146 static int __init gpio_clps711x_init(void)
 147 {
 148         int i;
 149         struct platform_device *pdev;
 150         struct clps711x_gpio *gpio;
 151
 152         pdev = platform_device_alloc(CLPS711X_GPIO_NAME, 0);
 153         if (!pdev) {
 154                 pr_err("Cannot create platform device: %s\n",
 155                        CLPS711X_GPIO_NAME);
 156                 return -ENOMEM;
 157         }
 158
 159         platform_device_add(pdev);
 160
 161         gpio = devm_kzalloc(&pdev->dev, sizeof(struct clps711x_gpio),
 162                             GFP_KERNEL);
 163         if (!gpio) {
 164                 dev_err(&pdev->dev, "GPIO allocating memory error\n");
 165                 platform_device_unregister(pdev);
 166                 return -ENOMEM;
 167         }
 168
 169         platform_set_drvdata(pdev, gpio);
 170
 171         spin_lock_init(&gpio->lock);
 172
 173         for (i = 0; i < CLPS711X_GPIO_PORTS; i++) {
 174                 gpio->chip[i].owner             = THIS_MODULE;
 175                 gpio->chip[i].dev               = &pdev->dev;
 176                 gpio->chip[i].label             = clps711x_gpio_ports[i].name;
 177                 gpio->chip[i].base              = i * 8;
 178                 gpio->chip[i].ngpio             = clps711x_gpio_ports[i].nr;
 179                 gpio->chip[i].get               = gpio_clps711x_get;
 180                 gpio->chip[i].set               = gpio_clps711x_set;
 181                 if (!clps711x_gpio_ports[i].inv_dir) {
 182                         gpio->chip[i].direction_input = gpio_clps711x_dir_in;
 183                         gpio->chip[i].direction_output = gpio_clps711x_dir_out;
 184                 } else {
 185                         gpio->chip[i].direction_input = gpio_clps711x_dir_in_inv;
 186                         gpio->chip[i].direction_output = gpio_clps711x_dir_out_inv;
 187                 }
 188                 WARN_ON(gpiochip_add(&gpio->chip[i]));
 189         }
 190
 191         dev_info(&pdev->dev, "GPIO driver initialized\n");
 192
 193         return 0;
 194 }
 195 arch_initcall(gpio_clps711x_init);
 196
 197 MODULE_LICENSE("GPL v2");
 198 MODULE_AUTHOR("Alexander Shiyan <shc_work@mail.ru>");
 199 MODULE_DESCRIPTION("CLPS711X GPIO driver");