Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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 int ret;
50
51 ret = regmap_update_bits(data->map, WCD_REG_DIR_CTL_OFFSET,
52 WCD_PIN_MASK(pin), WCD_PIN_MASK(pin));
53 if (ret)
54 return ret;
55
56 return regmap_update_bits(data->map, WCD_REG_VAL_CTL_OFFSET,
57 WCD_PIN_MASK(pin),
58 val ? WCD_PIN_MASK(pin) : 0);
59}
60
61static int wcd_gpio_get(struct gpio_chip *chip, unsigned int pin)
62{
63 struct wcd_gpio_data *data = gpiochip_get_data(chip);
64 unsigned int value;
65
66 regmap_read(data->map, WCD_REG_VAL_CTL_OFFSET, &value);
67
68 return !!(value & WCD_PIN_MASK(pin));
69}
70
71static int wcd_gpio_set(struct gpio_chip *chip, unsigned int pin, int val)
72{
73 struct wcd_gpio_data *data = gpiochip_get_data(chip);
74
75 return regmap_update_bits(data->map, WCD_REG_VAL_CTL_OFFSET,
76 WCD_PIN_MASK(pin),
77 val ? WCD_PIN_MASK(pin) : 0);
78}
79
80static int wcd_gpio_probe(struct platform_device *pdev)
81{
82 struct device *dev = &pdev->dev;
83 struct wcd_gpio_data *data;
84 struct gpio_chip *chip;
85
86 data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
87 if (!data)
88 return -ENOMEM;
89
90 data->map = dev_get_regmap(dev->parent, NULL);
91 if (!data->map) {
92 dev_err(dev, "%s: failed to get regmap\n", __func__);
93 return -EINVAL;
94 }
95
96 chip = &data->chip;
97 chip->direction_input = wcd_gpio_direction_input;
98 chip->direction_output = wcd_gpio_direction_output;
99 chip->get_direction = wcd_gpio_get_direction;
100 chip->get = wcd_gpio_get;
101 chip->set = wcd_gpio_set;
102 chip->parent = dev;
103 chip->base = -1;
104 chip->ngpio = WCD934X_NPINS;
105 chip->label = dev_name(dev);
106 chip->can_sleep = true;
107
108 return devm_gpiochip_add_data(dev, chip, data);
109}
110
111static const struct of_device_id wcd_gpio_of_match[] = {
112 { .compatible = "qcom,wcd9340-gpio" },
113 { .compatible = "qcom,wcd9341-gpio" },
114 { }
115};
116MODULE_DEVICE_TABLE(of, wcd_gpio_of_match);
117
118static struct platform_driver wcd_gpio_driver = {
119 .driver = {
120 .name = "wcd934x-gpio",
121 .of_match_table = wcd_gpio_of_match,
122 },
123 .probe = wcd_gpio_probe,
124};
125
126module_platform_driver(wcd_gpio_driver);
127MODULE_DESCRIPTION("Qualcomm Technologies, Inc WCD GPIO control driver");
128MODULE_LICENSE("GPL v2");