summaryrefslogtreecommitdiff
path: root/drivers/gpio/gpio-bd71828.c
blob: b2ccc320c7b53e77f4f3c06bfab37e881d8262b9 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
// 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");