LXR linux/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
  26struct bd9571mwv_gpio {
  27        struct gpio_chip chip;
  28        struct bd9571mwv *bd;
  29};
  30
  31static 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
  44static 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
  55static 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
  69static 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
  81static 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
  90static 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
 103static 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
 127static const struct platform_device_id bd9571mwv_gpio_id_table[] = {
 128        { "bd9571mwv-gpio", },
 129        { /* sentinel */ }
 130};
 131MODULE_DEVICE_TABLE(platform, bd9571mwv_gpio_id_table);
 132
 133static 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};
 140module_platform_driver(bd9571mwv_gpio_driver);
 141
 142MODULE_AUTHOR("Marek Vasut <marek.vasut+renesas@gmail.com>");
 143MODULE_DESCRIPTION("BD9571MWV GPIO driver");
 144MODULE_LICENSE("GPL v2");
 145