[linux-block.git] / drivers / gpio / gpio-bd71828.c

// 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 regmap *regmap;
	struct device *dev;
	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->regmap, GPIO_OUT_REG(offset),
				 BD71828_GPIO_OUT_MASK, val);
	if (ret)
		dev_err(bdgpio->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->regmap, BD71828_REG_IO_STAT,
				  &val);
	else
		ret = regmap_read(bdgpio->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->regmap,
					  GPIO_OUT_REG(offset),
					  BD71828_GPIO_DRIVE_MASK,
					  BD71828_GPIO_OPEN_DRAIN);
	case PIN_CONFIG_DRIVE_PUSH_PULL:
		return regmap_update_bits(bdgpio->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 device *dev = &pdev->dev;
	struct bd71828_gpio *bdgpio;

	bdgpio = devm_kzalloc(dev, sizeof(*bdgpio), GFP_KERNEL);
	if (!bdgpio)
		return -ENOMEM;

	bdgpio->dev = dev;
	bdgpio->gpio.parent = 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->regmap = dev_get_regmap(dev->parent, NULL);
	if (!bdgpio->regmap)
		return -ENODEV;

	return devm_gpiochip_add_data(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");
Commit	Line	Data
c31f625d MV	1	// SPDX-License-Identifier: GPL-2.0-only
	2	// Copyright (C) 2018 ROHM Semiconductors
	3
	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 3
	12
c31f625d	13	struct bd71828_gpio {
82bf0afd MV	14	struct regmap *regmap;
82bf0afd MV	15	struct device *dev;
c31f625d MV	16	struct gpio_chip gpio;
	17	};
	18
	19	static 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 pin
	28	* we are dealing with - then we are done
	29	*/
	30	if (offset == HALL_GPIO_OFFSET)
	31	return;
	32
82bf0afd	33	ret = regmap_update_bits(bdgpio->regmap, GPIO_OUT_REG(offset),
c31f625d MV	34	BD71828_GPIO_OUT_MASK, val);
c31f625d MV	35	if (ret)
82bf0afd	36	dev_err(bdgpio->dev, "Could not set gpio to %d\n", value);
c31f625d MV	37	}
	38
	39	static 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)
82bf0afd	46	ret = regmap_read(bdgpio->regmap, BD71828_REG_IO_STAT,
c31f625d MV	47	&val);
c31f625d MV	48	else
82bf0afd	49	ret = regmap_read(bdgpio->regmap, GPIO_OUT_REG(offset),
c31f625d MV	50	&val);
	51	if (!ret)
	52	ret = (val & BD71828_GPIO_OUT_MASK);
	53
	54	return ret;
	55	}
	56
	57	static 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:
82bf0afd	67	return regmap_update_bits(bdgpio->regmap,
c31f625d MV	68	GPIO_OUT_REG(offset),
	69	BD71828_GPIO_DRIVE_MASK,
	70	BD71828_GPIO_OPEN_DRAIN);
	71	case PIN_CONFIG_DRIVE_PUSH_PULL:
82bf0afd	72	return regmap_update_bits(bdgpio->regmap,
c31f625d MV	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
	82	static 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. Hence
	86	* 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 pin
	88	* on BD71828 can't really be used for general purpose input - input
	89	* states are used for specific cases like regulator control or
	90	* 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
	98	static int bd71828_probe(struct platform_device *pdev)
	99	{
cb38cd70	100	struct device *dev = &pdev->dev;
c31f625d	101	struct bd71828_gpio *bdgpio;
c31f625d	102
cb38cd70	103	bdgpio = devm_kzalloc(dev, sizeof(*bdgpio), GFP_KERNEL);
c31f625d MV	104	if (!bdgpio)
	105	return -ENOMEM;
	106
cb38cd70 BG	107	bdgpio->dev = dev;
cb38cd70 BG	108	bdgpio->gpio.parent = dev->parent;
c31f625d MV	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 as
	120	* not controllable based on DT info or if core can handle
	121	* "gpio-reserved-ranges" and exclude them from control
	122	*/
	123	bdgpio->gpio.ngpio = 4;
cb38cd70	124	bdgpio->regmap = dev_get_regmap(dev->parent, NULL);
82bf0afd MV	125	if (!bdgpio->regmap)
82bf0afd MV	126	return -ENODEV;
c31f625d	127
cb38cd70	128	return devm_gpiochip_add_data(dev, &bdgpio->gpio, bdgpio);
c31f625d MV	129	}
	130
	131	static struct platform_driver bd71828_gpio = {
	132	.driver = {
	133	.name = "bd71828-gpio"
	134	},
	135	.probe = bd71828_probe,
	136	};
	137
	138	module_platform_driver(bd71828_gpio);
	139
	140	MODULE_AUTHOR("Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>");
	141	MODULE_DESCRIPTION("BD71828 voltage regulator driver");
	142	MODULE_LICENSE("GPL");
	143	MODULE_ALIAS("platform:bd71828-gpio");