// SPDX-License-Identifier: GPL-2.0-only
// Copyright (C) 2018 ROHM Semiconductors
#include <linux/gpio/driver.h>
#include <linux/mfd/rohm-bd71828.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#define GPIO_OUT_REG(off) (BD71828_REG_GPIO_CTRL1 + (off))
#define HALL_GPIO_OFFSET 3
struct bd71828_gpio {
struct rohm_regmap_dev chip;
struct gpio_chip gpio;
};
static void bd71828_gpio_set(struct gpio_chip *chip, unsigned int offset,
int value)
{
int ret;
struct bd71828_gpio *bdgpio = gpiochip_get_data(chip);
u8 val = (value) ? BD71828_GPIO_OUT_HI : BD71828_GPIO_OUT_LO;
/*
* The HALL input pin can only be used as input. If this is the pin
* we are dealing with - then we are done
*/
if (offset == HALL_GPIO_OFFSET)
return;
ret = regmap_update_bits(bdgpio->chip.regmap, GPIO_OUT_REG(offset),
BD71828_GPIO_OUT_MASK, val);
if (ret)
dev_err(bdgpio->chip.dev, "Could not set gpio to %d\n", value);
}
static int bd71828_gpio_get(struct gpio_chip *chip, unsigned int offset)
{
int ret;
unsigned int val;
struct bd71828_gpio *bdgpio = gpiochip_get_data(chip);
if (offset == HALL_GPIO_OFFSET)
ret = regmap_read(bdgpio->chip.regmap, BD71828_REG_IO_STAT,
&val);
else
ret = regmap_read(bdgpio->chip.regmap, GPIO_OUT_REG(offset),
&val);
if (!ret)
ret = (val & BD71828_GPIO_OUT_MASK);
return ret;
}
static int bd71828_gpio_set_config(struct gpio_chip *chip, unsigned int offset,
unsigned long config)
{
struct bd71828_gpio *bdgpio = gpiochip_get_data(chip);
if (offset == HALL_GPIO_OFFSET)
return -ENOTSUPP;
switch (pinconf_to_config_param(config)) {
case PIN_CONFIG_DRIVE_OPEN_DRAIN:
return regmap_update_bits(bdgpio->chip.regmap,
GPIO_OUT_REG(offset),
BD71828_GPIO_DRIVE_MASK,
BD71828_GPIO_OPEN_DRAIN);
case PIN_CONFIG_DRIVE_PUSH_PULL:
return regmap_update_bits(bdgpio->chip.regmap,
GPIO_OUT_REG(offset),
BD71828_GPIO_DRIVE_MASK,
BD71828_GPIO_PUSH_PULL);
default:
break;
}
return -ENOTSUPP;
}
static int bd71828_get_direction(struct gpio_chip *chip, unsigned int offset)
{
/*
* Pin usage is selected by OTP data. We can't read it runtime. Hence
* we trust that if the pin is not excluded by "gpio-reserved-ranges"
* the OTP configuration is set to OUT. (Other pins but HALL input pin
* on BD71828 can't really be used for general purpose input - input
* states are used for specific cases like regulator control or
* PMIC_ON_REQ.
*/
if (offset == HALL_GPIO_OFFSET)
return GPIO_LINE_DIRECTION_IN;
return GPIO_LINE_DIRECTION_OUT;
}
static int bd71828_probe(struct platform_device *pdev)
{
struct bd71828_gpio *bdgpio;
struct rohm_regmap_dev *bd71828;
bd71828 = dev_get_drvdata(pdev->dev.parent);
if (!bd71828) {
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 = "bd71828-gpio";
bdgpio->gpio.owner = THIS_MODULE;
bdgpio->gpio.get_direction = bd71828_get_direction;
bdgpio->gpio.set_config = bd71828_gpio_set_config;
bdgpio->gpio.can_sleep = true;
bdgpio->gpio.get = bd71828_gpio_get;
bdgpio->gpio.set = bd71828_gpio_set;
bdgpio->gpio.base = -1;
/*
* See if we need some implementation to mark some PINs as
* not controllable based on DT info or if core can handle
* "gpio-reserved-ranges" and exclude them from control
*/
bdgpio->gpio.ngpio = 4;
bdgpio->gpio.of_node = pdev->dev.parent->of_node;
bdgpio->chip.regmap = bd71828->regmap;
return devm_gpiochip_add_data(&pdev->dev, &bdgpio->gpio,
bdgpio);
}
static struct platform_driver bd71828_gpio = {
.driver = {
.name = "bd71828-gpio"
},
.probe = bd71828_probe,
};
module_platform_driver(bd71828_gpio);
MODULE_AUTHOR("Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>");
MODULE_DESCRIPTION("BD71828 voltage regulator driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:bd71828-gpio");
