drivers/gpio/gpio-da9055.c

   1 /*
   2  * GPIO Driver for Dialog DA9055 PMICs.
   3  *
   4  * Copyright(c) 2012 Dialog Semiconductor Ltd.
   5  *
   6  * Author: David Dajun Chen <dchen@diasemi.com>
   7  *
   8  *  This program is free software; you can redistribute  it and/or modify it
   9  *  under  the terms of  the GNU General  Public License as published by the
  10  *  Free Software Foundation;  either version 2 of the  License, or (at your
  11  *  option) any later version.
  12  *
  13  */
  14 #include <linux/module.h>
  15 #include <linux/platform_device.h>
  16 #include <linux/gpio.h>
  17
  18 #include <linux/mfd/da9055/core.h>
  19 #include <linux/mfd/da9055/reg.h>
  20 #include <linux/mfd/da9055/pdata.h>
  21
  22 #define DA9055_VDD_IO                   0x0
  23 #define DA9055_PUSH_PULL                0x3
  24 #define DA9055_ACT_LOW                  0x0
  25 #define DA9055_GPI                      0x1
  26 #define DA9055_PORT_MASK                0x3
  27 #define DA9055_PORT_SHIFT(offset)       (4 * (offset % 2))
  28
  29 #define DA9055_INPUT                    DA9055_GPI
  30 #define DA9055_OUTPUT                   DA9055_PUSH_PULL
  31 #define DA9055_IRQ_GPI0                 3
  32
  33 struct da9055_gpio {
  34         struct da9055 *da9055;
  35         struct gpio_chip gp;
  36 };
  37
  38 static inline struct da9055_gpio *to_da9055_gpio(struct gpio_chip *chip)
  39 {
  40         return container_of(chip, struct da9055_gpio, gp);
  41 }
  42
  43 static int da9055_gpio_get(struct gpio_chip *gc, unsigned offset)
  44 {
  45         struct da9055_gpio *gpio = to_da9055_gpio(gc);
  46         int gpio_direction = 0;
  47         int ret;
  48
  49         /* Get GPIO direction */
  50         ret = da9055_reg_read(gpio->da9055, (offset >> 1) + DA9055_REG_GPIO0_1);
  51         if (ret < 0)
  52                 return ret;
  53
  54         gpio_direction = ret & (DA9055_PORT_MASK) << DA9055_PORT_SHIFT(offset);
  55         gpio_direction >>= DA9055_PORT_SHIFT(offset);
  56         switch (gpio_direction) {
  57         case DA9055_INPUT:
  58                 ret = da9055_reg_read(gpio->da9055, DA9055_REG_STATUS_B);
  59                 if (ret < 0)
  60                         return ret;
  61                 break;
  62         case DA9055_OUTPUT:
  63                 ret = da9055_reg_read(gpio->da9055, DA9055_REG_GPIO_MODE0_2);
  64                 if (ret < 0)
  65                         return ret;
  66         }
  67
  68         return ret & (1 << offset);
  69
  70 }
  71
  72 static void da9055_gpio_set(struct gpio_chip *gc, unsigned offset, int value)
  73 {
  74         struct da9055_gpio *gpio = to_da9055_gpio(gc);
  75
  76         da9055_reg_update(gpio->da9055,
  77                         DA9055_REG_GPIO_MODE0_2,
  78                         1 << offset,
  79                         value << offset);
  80 }
  81
  82 static int da9055_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
  83 {
  84         struct da9055_gpio *gpio = to_da9055_gpio(gc);
  85         unsigned char reg_byte;
  86
  87         reg_byte = (DA9055_ACT_LOW | DA9055_GPI)
  88                                 << DA9055_PORT_SHIFT(offset);
  89
  90         return da9055_reg_update(gpio->da9055, (offset >> 1) +
  91                                 DA9055_REG_GPIO0_1,
  92                                 DA9055_PORT_MASK <<
  93                                 DA9055_PORT_SHIFT(offset),
  94                                 reg_byte);
  95 }
  96
  97 static int da9055_gpio_direction_output(struct gpio_chip *gc,
  98                                         unsigned offset, int value)
  99 {
 100         struct da9055_gpio *gpio = to_da9055_gpio(gc);
 101         unsigned char reg_byte;
 102         int ret;
 103
 104         reg_byte = (DA9055_VDD_IO | DA9055_PUSH_PULL)
 105                                         << DA9055_PORT_SHIFT(offset);
 106
 107         ret = da9055_reg_update(gpio->da9055, (offset >> 1) +
 108                                 DA9055_REG_GPIO0_1,
 109                                 DA9055_PORT_MASK <<
 110                                 DA9055_PORT_SHIFT(offset),
 111                                 reg_byte);
 112         if (ret < 0)
 113                 return ret;
 114
 115         da9055_gpio_set(gc, offset, value);
 116
 117         return 0;
 118 }
 119
 120 static int da9055_gpio_to_irq(struct gpio_chip *gc, u32 offset)
 121 {
 122         struct da9055_gpio *gpio = to_da9055_gpio(gc);
 123         struct da9055 *da9055 = gpio->da9055;
 124
 125         return regmap_irq_get_virq(da9055->irq_data,
 126                                   DA9055_IRQ_GPI0 + offset);
 127 }
 128
 129 static struct gpio_chip reference_gp = {
 130         .label = "da9055-gpio",
 131         .owner = THIS_MODULE,
 132         .get = da9055_gpio_get,
 133         .set = da9055_gpio_set,
 134         .direction_input = da9055_gpio_direction_input,
 135         .direction_output = da9055_gpio_direction_output,
 136         .to_irq = da9055_gpio_to_irq,
 137         .can_sleep = true,
 138         .ngpio = 3,
 139         .base = -1,
 140 };
 141
 142 static int da9055_gpio_probe(struct platform_device *pdev)
 143 {
 144         struct da9055_gpio *gpio;
 145         struct da9055_pdata *pdata;
 146         int ret;
 147
 148         gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
 149         if (gpio == NULL)
 150                 return -ENOMEM;
 151
 152         gpio->da9055 = dev_get_drvdata(pdev->dev.parent);
 153         pdata = dev_get_platdata(gpio->da9055->dev);
 154
 155         gpio->gp = reference_gp;
 156         if (pdata && pdata->gpio_base)
 157                 gpio->gp.base = pdata->gpio_base;
 158
 159         ret = gpiochip_add(&gpio->gp);
 160         if (ret < 0) {
 161                 dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
 162                 goto err_mem;
 163         }
 164
 165         platform_set_drvdata(pdev, gpio);
 166
 167         return 0;
 168
 169 err_mem:
 170         return ret;
 171 }
 172
 173 static int da9055_gpio_remove(struct platform_device *pdev)
 174 {
 175         struct da9055_gpio *gpio = platform_get_drvdata(pdev);
 176
 177         gpiochip_remove(&gpio->gp);
 178         return 0;
 179 }
 180
 181 static struct platform_driver da9055_gpio_driver = {
 182         .probe = da9055_gpio_probe,
 183         .remove = da9055_gpio_remove,
 184         .driver = {
 185                 .name   = "da9055-gpio",
 186                 .owner  = THIS_MODULE,
 187         },
 188 };
 189
 190 static int __init da9055_gpio_init(void)
 191 {
 192         return platform_driver_register(&da9055_gpio_driver);
 193 }
 194 subsys_initcall(da9055_gpio_init);
 195
 196 static void __exit da9055_gpio_exit(void)
 197 {
 198         platform_driver_unregister(&da9055_gpio_driver);
 199 }
 200 module_exit(da9055_gpio_exit);
 201
 202 MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
 203 MODULE_DESCRIPTION("DA9055 GPIO Device Driver");
 204 MODULE_LICENSE("GPL");
 205 MODULE_ALIAS("platform:da9055-gpio");