1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2016 Texas Instruments Incorporated - http://www.ti.com/
4 *	Keerthy <j-keerthy@ti.com>
5 *
6 * Based on the TPS65218 driver
7 */
8
9#include <linux/gpio/driver.h>
10#include <linux/module.h>
11#include <linux/platform_device.h>
12#include <linux/regmap.h>
13
14#include <linux/mfd/lp873x.h>
15
16#define BITS_PER_GPO		0x4
17#define LP873X_GPO_CTRL_OD	0x2
18
19struct lp873x_gpio {
20	struct gpio_chip chip;
21	struct lp873x *lp873;
22};
23
24static int lp873x_gpio_get_direction(struct gpio_chip *chip,
25				     unsigned int offset)
26{
27	/* This device is output only */
28	return GPIO_LINE_DIRECTION_OUT;
29}
30
31static int lp873x_gpio_direction_input(struct gpio_chip *chip,
32				       unsigned int offset)
33{
34	/* This device is output only */
35	return -EINVAL;
36}
37
38static int lp873x_gpio_direction_output(struct gpio_chip *chip,
39					unsigned int offset, int value)
40{
41	struct lp873x_gpio *gpio = gpiochip_get_data(chip);
42
43	/* Set the initial value */
44	return regmap_update_bits(gpio->lp873->regmap, LP873X_REG_GPO_CTRL,
45				  BIT(offset * BITS_PER_GPO),
46				  value ? BIT(offset * BITS_PER_GPO) : 0);
47}
48
49static int lp873x_gpio_get(struct gpio_chip *chip, unsigned int offset)
50{
51	struct lp873x_gpio *gpio = gpiochip_get_data(chip);
52	int ret, val;
53
54	ret = regmap_read(gpio->lp873->regmap, LP873X_REG_GPO_CTRL, &val);
55	if (ret < 0)
56		return ret;
57
58	return val & BIT(offset * BITS_PER_GPO);
59}
60
61static void lp873x_gpio_set(struct gpio_chip *chip, unsigned int offset,
62			    int value)
63{
64	struct lp873x_gpio *gpio = gpiochip_get_data(chip);
65
66	regmap_update_bits(gpio->lp873->regmap, LP873X_REG_GPO_CTRL,
67			   BIT(offset * BITS_PER_GPO),
68			   value ? BIT(offset * BITS_PER_GPO) : 0);
69}
70
71static int lp873x_gpio_request(struct gpio_chip *gc, unsigned int offset)
72{
73	struct lp873x_gpio *gpio = gpiochip_get_data(gc);
74	int ret;
75
76	switch (offset) {
77	case 0:
78		/* No MUX Set up Needed for GPO */
79		break;
80	case 1:
81		/* Setup the CLKIN_PIN_SEL MUX to GPO2 */
82		ret = regmap_update_bits(gpio->lp873->regmap, LP873X_REG_CONFIG,
83					 LP873X_CONFIG_CLKIN_PIN_SEL, 0);
84		if (ret)
85			return ret;
86
87		break;
88	default:
89		return -EINVAL;
90	}
91
92	return 0;
93}
94
95static int lp873x_gpio_set_config(struct gpio_chip *gc, unsigned offset,
96				  unsigned long config)
97{
98	struct lp873x_gpio *gpio = gpiochip_get_data(gc);
99
100	switch (pinconf_to_config_param(config)) {
101	case PIN_CONFIG_DRIVE_OPEN_DRAIN:
102		return regmap_update_bits(gpio->lp873->regmap,
103					  LP873X_REG_GPO_CTRL,
104					  BIT(offset * BITS_PER_GPO +
105					  LP873X_GPO_CTRL_OD),
106					  BIT(offset * BITS_PER_GPO +
107					  LP873X_GPO_CTRL_OD));
108
109	case PIN_CONFIG_DRIVE_PUSH_PULL:
110		return regmap_update_bits(gpio->lp873->regmap,
111					  LP873X_REG_GPO_CTRL,
112					  BIT(offset * BITS_PER_GPO +
113					  LP873X_GPO_CTRL_OD), 0);
114	default:
115		return -ENOTSUPP;
116	}
117}
118
119static const struct gpio_chip template_chip = {
120	.label			= "lp873x-gpio",
121	.owner			= THIS_MODULE,
122	.request		= lp873x_gpio_request,
123	.get_direction		= lp873x_gpio_get_direction,
124	.direction_input	= lp873x_gpio_direction_input,
125	.direction_output	= lp873x_gpio_direction_output,
126	.get			= lp873x_gpio_get,
127	.set			= lp873x_gpio_set,
128	.set_config		= lp873x_gpio_set_config,
129	.base			= -1,
130	.ngpio			= 2,
131	.can_sleep		= true,
132};
133
134static int lp873x_gpio_probe(struct platform_device *pdev)
135{
136	struct lp873x_gpio *gpio;
137	int ret;
138
139	gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
140	if (!gpio)
141		return -ENOMEM;
142
143	platform_set_drvdata(pdev, gpio);
144
145	gpio->lp873 = dev_get_drvdata(pdev->dev.parent);
146	gpio->chip = template_chip;
147	gpio->chip.parent = gpio->lp873->dev;
148
149	ret = devm_gpiochip_add_data(&pdev->dev, &gpio->chip, gpio);
150	if (ret < 0) {
151		dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
152		return ret;
153	}
154
155	return 0;
156}
157
158static const struct platform_device_id lp873x_gpio_id_table[] = {
159	{ "lp873x-gpio", },
160	{ /* sentinel */ }
161};
162MODULE_DEVICE_TABLE(platform, lp873x_gpio_id_table);
163
164static struct platform_driver lp873x_gpio_driver = {
165	.driver = {
166		.name = "lp873x-gpio",
167	},
168	.probe = lp873x_gpio_probe,
169	.id_table = lp873x_gpio_id_table,
170};
171module_platform_driver(lp873x_gpio_driver);
172
173MODULE_AUTHOR("Keerthy <j-keerthy@ti.com>");
174MODULE_DESCRIPTION("LP873X GPIO driver");
175MODULE_LICENSE("GPL v2");
176