xref: /openbmc/linux/drivers/gpio/gpio-wcd934x.c (revision e91d0f05)
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 
16 struct wcd_gpio_data {
17 	struct regmap *map;
18 	struct gpio_chip chip;
19 };
20 
wcd_gpio_get_direction(struct gpio_chip * chip,unsigned int pin)21 static 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 
wcd_gpio_direction_input(struct gpio_chip * chip,unsigned int pin)37 static 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 
wcd_gpio_direction_output(struct gpio_chip * chip,unsigned int pin,int val)45 static 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 
wcd_gpio_get(struct gpio_chip * chip,unsigned int pin)58 static 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 
wcd_gpio_set(struct gpio_chip * chip,unsigned int pin,int val)68 static 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 
wcd_gpio_probe(struct platform_device * pdev)76 static 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 
107 static const struct of_device_id wcd_gpio_of_match[] = {
108 	{ .compatible = "qcom,wcd9340-gpio" },
109 	{ .compatible = "qcom,wcd9341-gpio" },
110 	{ }
111 };
112 MODULE_DEVICE_TABLE(of, wcd_gpio_of_match);
113 
114 static 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 
122 module_platform_driver(wcd_gpio_driver);
123 MODULE_DESCRIPTION("Qualcomm Technologies, Inc WCD GPIO control driver");
124 MODULE_LICENSE("GPL v2");
125