1// SPDX-License-Identifier: GPL-2.0
2// Copyright (c) 2019, Linaro Limited
3
4#include <linux/mod_devicetable.h>
5#include <linux/module.h>
6#include <linux/gpio/driver.h>
7#include <linux/platform_device.h>
8#include <linux/regmap.h>
9#include <linux/slab.h>
10
11#define WCD_PIN_MASK(p) BIT(p)
12#define WCD_REG_DIR_CTL_OFFSET 0x42
13#define WCD_REG_VAL_CTL_OFFSET 0x43
14#define WCD934X_NPINS		5
15
16struct wcd_gpio_data {
17	struct regmap *map;
18	struct gpio_chip chip;
19};
20
21static int wcd_gpio_get_direction(struct gpio_chip *chip, unsigned int pin)
22{
23	struct wcd_gpio_data *data = gpiochip_get_data(chip);
24	unsigned int value;
25	int ret;
26
27	ret = regmap_read(data->map, WCD_REG_DIR_CTL_OFFSET, &value);
28	if (ret < 0)
29		return ret;
30
31	if (value & WCD_PIN_MASK(pin))
32		return GPIO_LINE_DIRECTION_OUT;
33
34	return GPIO_LINE_DIRECTION_IN;
35}
36
37static int wcd_gpio_direction_input(struct gpio_chip *chip, unsigned int pin)
38{
39	struct wcd_gpio_data *data = gpiochip_get_data(chip);
40
41	return regmap_update_bits(data->map, WCD_REG_DIR_CTL_OFFSET,
42				  WCD_PIN_MASK(pin), 0);
43}
44
45static int wcd_gpio_direction_output(struct gpio_chip *chip, unsigned int pin,
46				     int val)
47{
48	struct wcd_gpio_data *data = gpiochip_get_data(chip);
49
50	regmap_update_bits(data->map, WCD_REG_DIR_CTL_OFFSET,
51			   WCD_PIN_MASK(pin), WCD_PIN_MASK(pin));
52
53	return regmap_update_bits(data->map, WCD_REG_VAL_CTL_OFFSET,
54				  WCD_PIN_MASK(pin),
55				  val ? WCD_PIN_MASK(pin) : 0);
56}
57
58static int wcd_gpio_get(struct gpio_chip *chip, unsigned int pin)
59{
60	struct wcd_gpio_data *data = gpiochip_get_data(chip);
61	unsigned int value;
62
63	regmap_read(data->map, WCD_REG_VAL_CTL_OFFSET, &value);
64
65	return !!(value & WCD_PIN_MASK(pin));
66}
67
68static void wcd_gpio_set(struct gpio_chip *chip, unsigned int pin, int val)
69{
70	struct wcd_gpio_data *data = gpiochip_get_data(chip);
71
72	regmap_update_bits(data->map, WCD_REG_VAL_CTL_OFFSET,
73			   WCD_PIN_MASK(pin), val ? WCD_PIN_MASK(pin) : 0);
74}
75
76static int wcd_gpio_probe(struct platform_device *pdev)
77{
78	struct device *dev = &pdev->dev;
79	struct wcd_gpio_data *data;
80	struct gpio_chip *chip;
81
82	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
83	if (!data)
84		return -ENOMEM;
85
86	data->map = dev_get_regmap(dev->parent, NULL);
87	if (!data->map) {
88		dev_err(dev, "%s: failed to get regmap\n", __func__);
89		return  -EINVAL;
90	}
91
92	chip = &data->chip;
93	chip->direction_input  = wcd_gpio_direction_input;
94	chip->direction_output = wcd_gpio_direction_output;
95	chip->get_direction = wcd_gpio_get_direction;
96	chip->get = wcd_gpio_get;
97	chip->set = wcd_gpio_set;
98	chip->parent = dev;
99	chip->base = -1;
100	chip->ngpio = WCD934X_NPINS;
101	chip->label = dev_name(dev);
102	chip->can_sleep = false;
103
104	return devm_gpiochip_add_data(dev, chip, data);
105}
106
107static const struct of_device_id wcd_gpio_of_match[] = {
108	{ .compatible = "qcom,wcd9340-gpio" },
109	{ .compatible = "qcom,wcd9341-gpio" },
110	{ }
111};
112MODULE_DEVICE_TABLE(of, wcd_gpio_of_match);
113
114static struct platform_driver wcd_gpio_driver = {
115	.driver = {
116		   .name = "wcd934x-gpio",
117		   .of_match_table = wcd_gpio_of_match,
118	},
119	.probe = wcd_gpio_probe,
120};
121
122module_platform_driver(wcd_gpio_driver);
123MODULE_DESCRIPTION("Qualcomm Technologies, Inc WCD GPIO control driver");
124MODULE_LICENSE("GPL v2");
125