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");