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        if (val & BIT(offset))
  41                return GPIO_LINE_DIRECTION_IN;
  42
  43        return GPIO_LINE_DIRECTION_OUT;
  44}
  45
  46static int bd9571mwv_gpio_direction_input(struct gpio_chip *chip,
  47                                         unsigned int offset)
  48{
  49        struct bd9571mwv_gpio *gpio = gpiochip_get_data(chip);
  50
  51        regmap_update_bits(gpio->bd->regmap, BD9571MWV_GPIO_DIR,
  52                           BIT(offset), 0);
  53
  54        return 0;
  55}
  56
  57static int bd9571mwv_gpio_direction_output(struct gpio_chip *chip,
  58                                          unsigned int offset, int value)
  59{
  60        struct bd9571mwv_gpio *gpio = gpiochip_get_data(chip);
  61
  62        /* Set the initial value */
  63        regmap_update_bits(gpio->bd->regmap, BD9571MWV_GPIO_OUT,
  64                           BIT(offset), value ? BIT(offset) : 0);
  65        regmap_update_bits(gpio->bd->regmap, BD9571MWV_GPIO_DIR,
  66                           BIT(offset), BIT(offset));
  67
  68        return 0;
  69}
  70
  71static int bd9571mwv_gpio_get(struct gpio_chip *chip, unsigned int offset)
  72{
  73        struct bd9571mwv_gpio *gpio = gpiochip_get_data(chip);
  74        int ret, val;
  75
  76        ret = regmap_read(gpio->bd->regmap, BD9571MWV_GPIO_IN, &val);
  77        if (ret < 0)
  78                return ret;
  79
  80        return val & BIT(offset);
  81}
  82
  83static void bd9571mwv_gpio_set(struct gpio_chip *chip, unsigned int offset,
  84                              int value)
  85{
  86        struct bd9571mwv_gpio *gpio = gpiochip_get_data(chip);
  87
  88        regmap_update_bits(gpio->bd->regmap, BD9571MWV_GPIO_OUT,
  89                           BIT(offset), value ? BIT(offset) : 0);
  90}
  91
  92static const struct gpio_chip template_chip = {
  93        .label                  = "bd9571mwv-gpio",
  94        .owner                  = THIS_MODULE,
  95        .get_direction          = bd9571mwv_gpio_get_direction,
  96        .direction_input        = bd9571mwv_gpio_direction_input,
  97        .direction_output       = bd9571mwv_gpio_direction_output,
  98        .get                    = bd9571mwv_gpio_get,
  99        .set                    = bd9571mwv_gpio_set,
 100        .base                   = -1,
 101        .ngpio                  = 2,
 102        .can_sleep              = true,
 103};
 104
 105static int bd9571mwv_gpio_probe(struct platform_device *pdev)
 106{
 107        struct bd9571mwv_gpio *gpio;
 108        int ret;
 109
 110        gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
 111        if (!gpio)
 112                return -ENOMEM;
 113
 114        platform_set_drvdata(pdev, gpio);
 115
 116        gpio->bd = dev_get_drvdata(pdev->dev.parent);
 117        gpio->chip = template_chip;
 118        gpio->chip.parent = gpio->bd->dev;
 119
 120        ret = devm_gpiochip_add_data(&pdev->dev, &gpio->chip, gpio);
 121        if (ret < 0) {
 122                dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
 123                return ret;
 124        }
 125
 126        return 0;
 127}
 128
 129static const struct platform_device_id bd9571mwv_gpio_id_table[] = {
 130        { "bd9571mwv-gpio", },
 131        { /* sentinel */ }
 132};
 133MODULE_DEVICE_TABLE(platform, bd9571mwv_gpio_id_table);
 134
 135static struct platform_driver bd9571mwv_gpio_driver = {
 136        .driver = {
 137                .name = "bd9571mwv-gpio",
 138        },
 139        .probe = bd9571mwv_gpio_probe,
 140        .id_table = bd9571mwv_gpio_id_table,
 141};
 142module_platform_driver(bd9571mwv_gpio_driver);
 143
 144MODULE_AUTHOR("Marek Vasut <marek.vasut+renesas@gmail.com>");
 145MODULE_DESCRIPTION("BD9571MWV GPIO driver");
 146MODULE_LICENSE("GPL v2");
 147