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1// SPDX-License-Identifier: GPL-2.0-only2// Copyright (C) 2018 ROHM Semiconductors3 4#include <linux/gpio/driver.h>5#include <linux/mfd/rohm-bd71828.h>6#include <linux/module.h>7#include <linux/platform_device.h>8#include <linux/regmap.h>9 10#define GPIO_OUT_REG(off) (BD71828_REG_GPIO_CTRL1 + (off))11#define HALL_GPIO_OFFSET 312 13struct bd71828_gpio {14 struct regmap *regmap;15 struct device *dev;16 struct gpio_chip gpio;17};18 19static void bd71828_gpio_set(struct gpio_chip *chip, unsigned int offset,20 int value)21{22 int ret;23 struct bd71828_gpio *bdgpio = gpiochip_get_data(chip);24 u8 val = (value) ? BD71828_GPIO_OUT_HI : BD71828_GPIO_OUT_LO;25 26 /*27 * The HALL input pin can only be used as input. If this is the pin28 * we are dealing with - then we are done29 */30 if (offset == HALL_GPIO_OFFSET)31 return;32 33 ret = regmap_update_bits(bdgpio->regmap, GPIO_OUT_REG(offset),34 BD71828_GPIO_OUT_MASK, val);35 if (ret)36 dev_err(bdgpio->dev, "Could not set gpio to %d\n", value);37}38 39static int bd71828_gpio_get(struct gpio_chip *chip, unsigned int offset)40{41 int ret;42 unsigned int val;43 struct bd71828_gpio *bdgpio = gpiochip_get_data(chip);44 45 if (offset == HALL_GPIO_OFFSET)46 ret = regmap_read(bdgpio->regmap, BD71828_REG_IO_STAT,47 &val);48 else49 ret = regmap_read(bdgpio->regmap, GPIO_OUT_REG(offset),50 &val);51 if (!ret)52 ret = (val & BD71828_GPIO_OUT_MASK);53 54 return ret;55}56 57static int bd71828_gpio_set_config(struct gpio_chip *chip, unsigned int offset,58 unsigned long config)59{60 struct bd71828_gpio *bdgpio = gpiochip_get_data(chip);61 62 if (offset == HALL_GPIO_OFFSET)63 return -ENOTSUPP;64 65 switch (pinconf_to_config_param(config)) {66 case PIN_CONFIG_DRIVE_OPEN_DRAIN:67 return regmap_update_bits(bdgpio->regmap,68 GPIO_OUT_REG(offset),69 BD71828_GPIO_DRIVE_MASK,70 BD71828_GPIO_OPEN_DRAIN);71 case PIN_CONFIG_DRIVE_PUSH_PULL:72 return regmap_update_bits(bdgpio->regmap,73 GPIO_OUT_REG(offset),74 BD71828_GPIO_DRIVE_MASK,75 BD71828_GPIO_PUSH_PULL);76 default:77 break;78 }79 return -ENOTSUPP;80}81 82static int bd71828_get_direction(struct gpio_chip *chip, unsigned int offset)83{84 /*85 * Pin usage is selected by OTP data. We can't read it runtime. Hence86 * we trust that if the pin is not excluded by "gpio-reserved-ranges"87 * the OTP configuration is set to OUT. (Other pins but HALL input pin88 * on BD71828 can't really be used for general purpose input - input89 * states are used for specific cases like regulator control or90 * PMIC_ON_REQ.91 */92 if (offset == HALL_GPIO_OFFSET)93 return GPIO_LINE_DIRECTION_IN;94 95 return GPIO_LINE_DIRECTION_OUT;96}97 98static int bd71828_probe(struct platform_device *pdev)99{100 struct device *dev = &pdev->dev;101 struct bd71828_gpio *bdgpio;102 103 bdgpio = devm_kzalloc(dev, sizeof(*bdgpio), GFP_KERNEL);104 if (!bdgpio)105 return -ENOMEM;106 107 bdgpio->dev = dev;108 bdgpio->gpio.parent = dev->parent;109 bdgpio->gpio.label = "bd71828-gpio";110 bdgpio->gpio.owner = THIS_MODULE;111 bdgpio->gpio.get_direction = bd71828_get_direction;112 bdgpio->gpio.set_config = bd71828_gpio_set_config;113 bdgpio->gpio.can_sleep = true;114 bdgpio->gpio.get = bd71828_gpio_get;115 bdgpio->gpio.set = bd71828_gpio_set;116 bdgpio->gpio.base = -1;117 118 /*119 * See if we need some implementation to mark some PINs as120 * not controllable based on DT info or if core can handle121 * "gpio-reserved-ranges" and exclude them from control122 */123 bdgpio->gpio.ngpio = 4;124 bdgpio->regmap = dev_get_regmap(dev->parent, NULL);125 if (!bdgpio->regmap)126 return -ENODEV;127 128 return devm_gpiochip_add_data(dev, &bdgpio->gpio, bdgpio);129}130 131static struct platform_driver bd71828_gpio = {132 .driver = {133 .name = "bd71828-gpio"134 },135 .probe = bd71828_probe,136};137 138module_platform_driver(bd71828_gpio);139 140MODULE_AUTHOR("Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>");141MODULE_DESCRIPTION("BD71828 voltage regulator driver");142MODULE_LICENSE("GPL");143MODULE_ALIAS("platform:bd71828-gpio");144