drivers/gpio/gpio-bd9571mwv.c

   1 /*
   2  * ROHM BD9571MWV-M GPIO driver
   3  *
   4  * Copyright (C) 2017 Marek Vasut <marek.vasut+renesas@gmail.com>
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  *
  10  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
  11  * kind, whether expressed or implied; without even the implied warranty
  12  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License version 2 for more details.
  14  *
  15  * Based on the TPS65086 driver
  16  *
  17  * NOTE: Interrupts are not supported yet.
  18  */
  19
  20 #include <linux/gpio/driver.h>
  21 #include <linux/module.h>
  22 #include <linux/platform_device.h>
  23
  24 #include <linux/mfd/bd9571mwv.h>
  25
  26 struct bd9571mwv_gpio {
  27         struct gpio_chip chip;
  28         struct bd9571mwv *bd;
  29 };
  30
  31 static int bd9571mwv_gpio_get_direction(struct gpio_chip *chip,
  32                                        unsigned int offset)
  33 {
  34         struct bd9571mwv_gpio *gpio = gpiochip_get_data(chip);
  35         int ret, val;
  36
  37         ret = regmap_read(gpio->bd->regmap, BD9571MWV_GPIO_DIR, &val);
  38         if (ret < 0)
  39                 return ret;
  40
  41         return val & BIT(offset);
  42 }
  43
  44 static int bd9571mwv_gpio_direction_input(struct gpio_chip *chip,
  45                                          unsigned int offset)
  46 {
  47         struct bd9571mwv_gpio *gpio = gpiochip_get_data(chip);
  48
  49         regmap_update_bits(gpio->bd->regmap, BD9571MWV_GPIO_DIR,
  50                            BIT(offset), 0);
  51
  52         return 0;
  53 }
  54
  55 static int bd9571mwv_gpio_direction_output(struct gpio_chip *chip,
  56                                           unsigned int offset, int value)
  57 {
  58         struct bd9571mwv_gpio *gpio = gpiochip_get_data(chip);
  59
  60         /* Set the initial value */
  61         regmap_update_bits(gpio->bd->regmap, BD9571MWV_GPIO_OUT,
  62                            BIT(offset), value ? BIT(offset) : 0);
  63         regmap_update_bits(gpio->bd->regmap, BD9571MWV_GPIO_DIR,
  64                            BIT(offset), BIT(offset));
  65
  66         return 0;
  67 }
  68
  69 static int bd9571mwv_gpio_get(struct gpio_chip *chip, unsigned int offset)
  70 {
  71         struct bd9571mwv_gpio *gpio = gpiochip_get_data(chip);
  72         int ret, val;
  73
  74         ret = regmap_read(gpio->bd->regmap, BD9571MWV_GPIO_IN, &val);
  75         if (ret < 0)
  76                 return ret;
  77
  78         return val & BIT(offset);
  79 }
  80
  81 static void bd9571mwv_gpio_set(struct gpio_chip *chip, unsigned int offset,
  82                               int value)
  83 {
  84         struct bd9571mwv_gpio *gpio = gpiochip_get_data(chip);
  85
  86         regmap_update_bits(gpio->bd->regmap, BD9571MWV_GPIO_OUT,
  87                            BIT(offset), value ? BIT(offset) : 0);
  88 }
  89
  90 static const struct gpio_chip template_chip = {
  91         .label                  = "bd9571mwv-gpio",
  92         .owner                  = THIS_MODULE,
  93         .get_direction          = bd9571mwv_gpio_get_direction,
  94         .direction_input        = bd9571mwv_gpio_direction_input,
  95         .direction_output       = bd9571mwv_gpio_direction_output,
  96         .get                    = bd9571mwv_gpio_get,
  97         .set                    = bd9571mwv_gpio_set,
  98         .base                   = -1,
  99         .ngpio                  = 2,
 100         .can_sleep              = true,
 101 };
 102
 103 static int bd9571mwv_gpio_probe(struct platform_device *pdev)
 104 {
 105         struct bd9571mwv_gpio *gpio;
 106         int ret;
 107
 108         gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
 109         if (!gpio)
 110                 return -ENOMEM;
 111
 112         platform_set_drvdata(pdev, gpio);
 113
 114         gpio->bd = dev_get_drvdata(pdev->dev.parent);
 115         gpio->chip = template_chip;
 116         gpio->chip.parent = gpio->bd->dev;
 117
 118         ret = devm_gpiochip_add_data(&pdev->dev, &gpio->chip, gpio);
 119         if (ret < 0) {
 120                 dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
 121                 return ret;
 122         }
 123
 124         return 0;
 125 }
 126
 127 static const struct platform_device_id bd9571mwv_gpio_id_table[] = {
 128         { "bd9571mwv-gpio", },
 129         { /* sentinel */ }
 130 };
 131 MODULE_DEVICE_TABLE(platform, bd9571mwv_gpio_id_table);
 132
 133 static struct platform_driver bd9571mwv_gpio_driver = {
 134         .driver = {
 135                 .name = "bd9571mwv-gpio",
 136         },
 137         .probe = bd9571mwv_gpio_probe,
 138         .id_table = bd9571mwv_gpio_id_table,
 139 };
 140 module_platform_driver(bd9571mwv_gpio_driver);
 141
 142 MODULE_AUTHOR("Marek Vasut <marek.vasut+renesas@gmail.com>");
 143 MODULE_DESCRIPTION("BD9571MWV GPIO driver");
 144 MODULE_LICENSE("GPL v2");