1// SPDX-License-Identifier: GPL-2.0
2// Copyright (c) 2019, Linaro Limited
3
4#include <linux/module.h>
5#include <linux/gpio/driver.h>
6#include <linux/regmap.h>
7#include <linux/slab.h>
8#include <linux/of_device.h>
9
10#define WCD_PIN_MASK(p) BIT(p)
11#define WCD_REG_DIR_CTL_OFFSET 0x42
12#define WCD_REG_VAL_CTL_OFFSET 0x43
13#define WCD934X_NPINS		5
14
15struct wcd_gpio_data {
16	struct regmap *map;
17	struct gpio_chip chip;
18};
19
20static int wcd_gpio_get_direction(struct gpio_chip *chip, unsigned int pin)
21{
22	struct wcd_gpio_data *data = gpiochip_get_data(chip);
23	unsigned int value;
24	int ret;
25
26	ret = regmap_read(data->map, WCD_REG_DIR_CTL_OFFSET, &value);
27	if (ret < 0)
28		return ret;
29
30	if (value & WCD_PIN_MASK(pin))
31		return GPIO_LINE_DIRECTION_OUT;
32
33	return GPIO_LINE_DIRECTION_IN;
34}
35
36static int wcd_gpio_direction_input(struct gpio_chip *chip, unsigned int pin)
37{
38	struct wcd_gpio_data *data = gpiochip_get_data(chip);
39
40	return regmap_update_bits(data->map, WCD_REG_DIR_CTL_OFFSET,
41				  WCD_PIN_MASK(pin), 0);
42}
43
44static int wcd_gpio_direction_output(struct gpio_chip *chip, unsigned int pin,
45				     int val)
46{
47	struct wcd_gpio_data *data = gpiochip_get_data(chip);
48
49	regmap_update_bits(data->map, WCD_REG_DIR_CTL_OFFSET,
50			   WCD_PIN_MASK(pin), WCD_PIN_MASK(pin));
51
52	return regmap_update_bits(data->map, WCD_REG_VAL_CTL_OFFSET,
53				  WCD_PIN_MASK(pin),
54				  val ? WCD_PIN_MASK(pin) : 0);
55}
56
57static int wcd_gpio_get(struct gpio_chip *chip, unsigned int pin)
58{
59	struct wcd_gpio_data *data = gpiochip_get_data(chip);
60	unsigned int value;
61
62	regmap_read(data->map, WCD_REG_VAL_CTL_OFFSET, &value);
63
64	return !!(value & WCD_PIN_MASK(pin));
65}
66
67static void wcd_gpio_set(struct gpio_chip *chip, unsigned int pin, int val)
68{
69	struct wcd_gpio_data *data = gpiochip_get_data(chip);
70
71	regmap_update_bits(data->map, WCD_REG_VAL_CTL_OFFSET,
72			   WCD_PIN_MASK(pin), val ? WCD_PIN_MASK(pin) : 0);
73}
74
75static int wcd_gpio_probe(struct platform_device *pdev)
76{
77	struct device *dev = &pdev->dev;
78	struct wcd_gpio_data *data;
79	struct gpio_chip *chip;
80
81	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
82	if (!data)
83		return -ENOMEM;
84
85	data->map = dev_get_regmap(dev->parent, NULL);
86	if (!data->map) {
87		dev_err(dev, "%s: failed to get regmap\n", __func__);
88		return  -EINVAL;
89	}
90
91	chip = &data->chip;
92	chip->direction_input  = wcd_gpio_direction_input;
93	chip->direction_output = wcd_gpio_direction_output;
94	chip->get_direction = wcd_gpio_get_direction;
95	chip->get = wcd_gpio_get;
96	chip->set = wcd_gpio_set;
97	chip->parent = dev;
98	chip->base = -1;
99	chip->ngpio = WCD934X_NPINS;
100	chip->label = dev_name(dev);
101	chip->of_gpio_n_cells = 2;
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