1 // SPDX-License-Identifier: GPL-2.0-only
2 // Copyright (C) 2018 ROHM Semiconductors
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>
10 #define GPIO_OUT_REG(off) (BD71828_REG_GPIO_CTRL1 + (off))
11 #define HALL_GPIO_OFFSET 3
14 struct rohm_regmap_dev chip;
15 struct gpio_chip gpio;
18 static void bd71828_gpio_set(struct gpio_chip *chip, unsigned int offset,
22 struct bd71828_gpio *bdgpio = gpiochip_get_data(chip);
23 u8 val = (value) ? BD71828_GPIO_OUT_HI : BD71828_GPIO_OUT_LO;
26 * The HALL input pin can only be used as input. If this is the pin
27 * we are dealing with - then we are done
29 if (offset == HALL_GPIO_OFFSET)
32 ret = regmap_update_bits(bdgpio->chip.regmap, GPIO_OUT_REG(offset),
33 BD71828_GPIO_OUT_MASK, val);
35 dev_err(bdgpio->chip.dev, "Could not set gpio to %d\n", value);
38 static int bd71828_gpio_get(struct gpio_chip *chip, unsigned int offset)
42 struct bd71828_gpio *bdgpio = gpiochip_get_data(chip);
44 if (offset == HALL_GPIO_OFFSET)
45 ret = regmap_read(bdgpio->chip.regmap, BD71828_REG_IO_STAT,
48 ret = regmap_read(bdgpio->chip.regmap, GPIO_OUT_REG(offset),
51 ret = (val & BD71828_GPIO_OUT_MASK);
56 static int bd71828_gpio_set_config(struct gpio_chip *chip, unsigned int offset,
59 struct bd71828_gpio *bdgpio = gpiochip_get_data(chip);
61 if (offset == HALL_GPIO_OFFSET)
64 switch (pinconf_to_config_param(config)) {
65 case PIN_CONFIG_DRIVE_OPEN_DRAIN:
66 return regmap_update_bits(bdgpio->chip.regmap,
68 BD71828_GPIO_DRIVE_MASK,
69 BD71828_GPIO_OPEN_DRAIN);
70 case PIN_CONFIG_DRIVE_PUSH_PULL:
71 return regmap_update_bits(bdgpio->chip.regmap,
73 BD71828_GPIO_DRIVE_MASK,
74 BD71828_GPIO_PUSH_PULL);
81 static int bd71828_get_direction(struct gpio_chip *chip, unsigned int offset)
84 * Pin usage is selected by OTP data. We can't read it runtime. Hence
85 * we trust that if the pin is not excluded by "gpio-reserved-ranges"
86 * the OTP configuration is set to OUT. (Other pins but HALL input pin
87 * on BD71828 can't really be used for general purpose input - input
88 * states are used for specific cases like regulator control or
91 if (offset == HALL_GPIO_OFFSET)
92 return GPIO_LINE_DIRECTION_IN;
94 return GPIO_LINE_DIRECTION_OUT;
97 static int bd71828_probe(struct platform_device *pdev)
99 struct bd71828_gpio *bdgpio;
100 struct rohm_regmap_dev *bd71828;
102 bd71828 = dev_get_drvdata(pdev->dev.parent);
104 dev_err(&pdev->dev, "No MFD driver data\n");
108 bdgpio = devm_kzalloc(&pdev->dev, sizeof(*bdgpio),
113 bdgpio->chip.dev = &pdev->dev;
114 bdgpio->gpio.parent = pdev->dev.parent;
115 bdgpio->gpio.label = "bd71828-gpio";
116 bdgpio->gpio.owner = THIS_MODULE;
117 bdgpio->gpio.get_direction = bd71828_get_direction;
118 bdgpio->gpio.set_config = bd71828_gpio_set_config;
119 bdgpio->gpio.can_sleep = true;
120 bdgpio->gpio.get = bd71828_gpio_get;
121 bdgpio->gpio.set = bd71828_gpio_set;
122 bdgpio->gpio.base = -1;
125 * See if we need some implementation to mark some PINs as
126 * not controllable based on DT info or if core can handle
127 * "gpio-reserved-ranges" and exclude them from control
129 bdgpio->gpio.ngpio = 4;
130 bdgpio->gpio.of_node = pdev->dev.parent->of_node;
131 bdgpio->chip.regmap = bd71828->regmap;
133 return devm_gpiochip_add_data(&pdev->dev, &bdgpio->gpio,
137 static struct platform_driver bd71828_gpio = {
139 .name = "bd71828-gpio"
141 .probe = bd71828_probe,
144 module_platform_driver(bd71828_gpio);
146 MODULE_AUTHOR("Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>");
147 MODULE_DESCRIPTION("BD71828 voltage regulator driver");
148 MODULE_LICENSE("GPL");
149 MODULE_ALIAS("platform:bd71828-gpio");