// SPDX-License-Identifier: GPL-2.0 // Copyright (C) 2018 ROHM Semiconductors // gpio-bd70528.c ROHM BD70528MWV gpio driver #include <linux/gpio/driver.h> #include <linux/mfd/rohm-bd70528.h> #include <linux/module.h> #include <linux/platform_device.h> #include <linux/regmap.h> #define GPIO_IN_REG(offset) (BD70528_REG_GPIO1_IN + (offset) * 2) #define GPIO_OUT_REG(offset) (BD70528_REG_GPIO1_OUT + (offset) * 2) struct bd70528_gpio { struct rohm_regmap_dev chip; struct gpio_chip gpio; }; static int bd70528_set_debounce(struct bd70528_gpio *bdgpio, unsigned int offset, unsigned int debounce) { u8 val; switch (debounce) { case 0: val = BD70528_DEBOUNCE_DISABLE; break; case 1 ... 15000: val = BD70528_DEBOUNCE_15MS; break; case 15001 ... 30000: val = BD70528_DEBOUNCE_30MS; break; case 30001 ... 50000: val = BD70528_DEBOUNCE_50MS; break; default: dev_err(bdgpio->chip.dev, "Invalid debounce value %u\n", debounce); return -EINVAL; } return regmap_update_bits(bdgpio->chip.regmap, GPIO_IN_REG(offset), BD70528_DEBOUNCE_MASK, val); } static int bd70528_get_direction(struct gpio_chip *chip, unsigned int offset) { struct bd70528_gpio *bdgpio = gpiochip_get_data(chip); int val, ret; /* Do we need to do something to IRQs here? */ ret = regmap_read(bdgpio->chip.regmap, GPIO_OUT_REG(offset), &val); if (ret) { dev_err(bdgpio->chip.dev, "Could not read gpio direction\n"); return ret; } if (val & BD70528_GPIO_OUT_EN_MASK) return GPIO_LINE_DIRECTION_OUT; return GPIO_LINE_DIRECTION_IN; } static int bd70528_gpio_set_config(struct gpio_chip *chip, unsigned int offset, unsigned long config) { struct bd70528_gpio *bdgpio = gpiochip_get_data(chip); switch (pinconf_to_config_param(config)) { case PIN_CONFIG_DRIVE_OPEN_DRAIN: return regmap_update_bits(bdgpio->chip.regmap, GPIO_OUT_REG(offset), BD70528_GPIO_DRIVE_MASK, BD70528_GPIO_OPEN_DRAIN); break; case PIN_CONFIG_DRIVE_PUSH_PULL: return regmap_update_bits(bdgpio->chip.regmap, GPIO_OUT_REG(offset), BD70528_GPIO_DRIVE_MASK, BD70528_GPIO_PUSH_PULL); break; case PIN_CONFIG_INPUT_DEBOUNCE: return bd70528_set_debounce(bdgpio, offset, pinconf_to_config_argument(config)); break; default: break; } return -ENOTSUPP; } static int bd70528_direction_input(struct gpio_chip *chip, unsigned int offset) { struct bd70528_gpio *bdgpio = gpiochip_get_data(chip); /* Do we need to do something to IRQs here? */ return regmap_update_bits(bdgpio->chip.regmap, GPIO_OUT_REG(offset), BD70528_GPIO_OUT_EN_MASK, BD70528_GPIO_OUT_DISABLE); } static void bd70528_gpio_set(struct gpio_chip *chip, unsigned int offset, int value) { int ret; struct bd70528_gpio *bdgpio = gpiochip_get_data(chip); u8 val = (value) ? BD70528_GPIO_OUT_HI : BD70528_GPIO_OUT_LO; ret = regmap_update_bits(bdgpio->chip.regmap, GPIO_OUT_REG(offset), BD70528_GPIO_OUT_MASK, val); if (ret) dev_err(bdgpio->chip.dev, "Could not set gpio to %d\n", value); } static int bd70528_direction_output(struct gpio_chip *chip, unsigned int offset, int value) { struct bd70528_gpio *bdgpio = gpiochip_get_data(chip); bd70528_gpio_set(chip, offset, value); return regmap_update_bits(bdgpio->chip.regmap, GPIO_OUT_REG(offset), BD70528_GPIO_OUT_EN_MASK, BD70528_GPIO_OUT_ENABLE); } #define GPIO_IN_STATE_MASK(offset) (BD70528_GPIO_IN_STATE_BASE << (offset)) static int bd70528_gpio_get_o(struct bd70528_gpio *bdgpio, unsigned int offset) { int ret; unsigned int val; ret = regmap_read(bdgpio->chip.regmap, GPIO_OUT_REG(offset), &val); if (!ret) ret = !!(val & BD70528_GPIO_OUT_MASK); else dev_err(bdgpio->chip.dev, "GPIO (out) state read failed\n"); return ret; } static int bd70528_gpio_get_i(struct bd70528_gpio *bdgpio, unsigned int offset) { unsigned int val; int ret; ret = regmap_read(bdgpio->chip.regmap, BD70528_REG_GPIO_STATE, &val); if (!ret) ret = !(val & GPIO_IN_STATE_MASK(offset)); else dev_err(bdgpio->chip.dev, "GPIO (in) state read failed\n"); return ret; } static int bd70528_gpio_get(struct gpio_chip *chip, unsigned int offset) { int ret; struct bd70528_gpio *bdgpio = gpiochip_get_data(chip); /* * There is a race condition where someone might be changing the * GPIO direction after we get it but before we read the value. But * application design where GPIO direction may be changed just when * we read GPIO value would be pointless as reader could not know * whether the returned high/low state is caused by input or output. * Or then there must be other ways to mitigate the issue. Thus * locking would make no sense. */ ret = bd70528_get_direction(chip, offset); if (ret == GPIO_LINE_DIRECTION_OUT) ret = bd70528_gpio_get_o(bdgpio, offset); else if (ret == GPIO_LINE_DIRECTION_IN) ret = bd70528_gpio_get_i(bdgpio, offset); else dev_err(bdgpio->chip.dev, "failed to read GPIO direction\n"); return ret; } static int bd70528_probe(struct platform_device *pdev) { struct bd70528_gpio *bdgpio; struct rohm_regmap_dev *bd70528; int ret; bd70528 = dev_get_drvdata(pdev->dev.parent); if (!bd70528) { dev_err(&pdev->dev, "No MFD driver data\n"); return -EINVAL; } bdgpio = devm_kzalloc(&pdev->dev, sizeof(*bdgpio), GFP_KERNEL); if (!bdgpio) return -ENOMEM; bdgpio->chip.dev = &pdev->dev; bdgpio->gpio.parent = pdev->dev.parent; bdgpio->gpio.label = "bd70528-gpio"; bdgpio->gpio.owner = THIS_MODULE; bdgpio->gpio.get_direction = bd70528_get_direction; bdgpio->gpio.direction_input = bd70528_direction_input; bdgpio->gpio.direction_output = bd70528_direction_output; bdgpio->gpio.set_config = bd70528_gpio_set_config; bdgpio->gpio.can_sleep = true; bdgpio->gpio.get = bd70528_gpio_get; bdgpio->gpio.set = bd70528_gpio_set; bdgpio->gpio.ngpio = 4; bdgpio->gpio.base = -1; #ifdef CONFIG_OF_GPIO bdgpio->gpio.of_node = pdev->dev.parent->of_node; #endif bdgpio->chip.regmap = bd70528->regmap; ret = devm_gpiochip_add_data(&pdev->dev, &bdgpio->gpio, bdgpio); if (ret) dev_err(&pdev->dev, "gpio_init: Failed to add bd70528-gpio\n"); return ret; } static struct platform_driver bd70528_gpio = { .driver = { .name = "bd70528-gpio" }, .probe = bd70528_probe, }; module_platform_driver(bd70528_gpio); MODULE_AUTHOR("Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>"); MODULE_DESCRIPTION("BD70528 voltage regulator driver"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:bd70528-gpio");