gpio-max77650.c

  1// SPDX-License-Identifier: GPL-2.0
  2//
  3// Copyright (C) 2018 BayLibre SAS
  4// Author: Bartosz Golaszewski <bgolaszewski@baylibre.com>
  5//
  6// GPIO driver for MAXIM 77650/77651 charger/power-supply.
  7
  8#include <linux/gpio/driver.h>
  9#include <linux/i2c.h>
 10#include <linux/mfd/max77650.h>
 11#include <linux/module.h>
 12#include <linux/platform_device.h>
 13#include <linux/regmap.h>
 14
 15#define MAX77650_GPIO_DIR_MASK		BIT(0)
 16#define MAX77650_GPIO_INVAL_MASK	BIT(1)
 17#define MAX77650_GPIO_DRV_MASK		BIT(2)
 18#define MAX77650_GPIO_OUTVAL_MASK	BIT(3)
 19#define MAX77650_GPIO_DEBOUNCE_MASK	BIT(4)
 20
 21#define MAX77650_GPIO_DIR_OUT		0x00
 22#define MAX77650_GPIO_DIR_IN		BIT(0)
 23#define MAX77650_GPIO_OUT_LOW		0x00
 24#define MAX77650_GPIO_OUT_HIGH		BIT(3)
 25#define MAX77650_GPIO_DRV_OPEN_DRAIN	0x00
 26#define MAX77650_GPIO_DRV_PUSH_PULL	BIT(2)
 27#define MAX77650_GPIO_DEBOUNCE		BIT(4)
 28
 29#define MAX77650_GPIO_DIR_BITS(_reg) \
 30		((_reg) & MAX77650_GPIO_DIR_MASK)
 31#define MAX77650_GPIO_INVAL_BITS(_reg) \
 32		(((_reg) & MAX77650_GPIO_INVAL_MASK) >> 1)
 33
 34struct max77650_gpio_chip {
 35	struct regmap *map;
 36	struct gpio_chip gc;
 37	int irq;
 38};
 39
 40static int max77650_gpio_direction_input(struct gpio_chip *gc,
 41					 unsigned int offset)
 42{
 43	struct max77650_gpio_chip *chip = gpiochip_get_data(gc);
 44
 45	return regmap_update_bits(chip->map,
 46				  MAX77650_REG_CNFG_GPIO,
 47				  MAX77650_GPIO_DIR_MASK,
 48				  MAX77650_GPIO_DIR_IN);
 49}
 50
 51static int max77650_gpio_direction_output(struct gpio_chip *gc,
 52					  unsigned int offset, int value)
 53{
 54	struct max77650_gpio_chip *chip = gpiochip_get_data(gc);
 55	int mask, regval;
 56
 57	mask = MAX77650_GPIO_DIR_MASK | MAX77650_GPIO_OUTVAL_MASK;
 58	regval = value ? MAX77650_GPIO_OUT_HIGH : MAX77650_GPIO_OUT_LOW;
 59	regval |= MAX77650_GPIO_DIR_OUT;
 60
 61	return regmap_update_bits(chip->map,
 62				  MAX77650_REG_CNFG_GPIO, mask, regval);
 63}
 64
 65static int max77650_gpio_set_value(struct gpio_chip *gc,
 66				   unsigned int offset, int value)
 67{
 68	struct max77650_gpio_chip *chip = gpiochip_get_data(gc);
 69	int regval;
 70
 71	regval = value ? MAX77650_GPIO_OUT_HIGH : MAX77650_GPIO_OUT_LOW;
 72
 73	return regmap_update_bits(chip->map, MAX77650_REG_CNFG_GPIO,
 74				  MAX77650_GPIO_OUTVAL_MASK, regval);
 75}
 76
 77static int max77650_gpio_get_value(struct gpio_chip *gc,
 78				   unsigned int offset)
 79{
 80	struct max77650_gpio_chip *chip = gpiochip_get_data(gc);
 81	unsigned int val;
 82	int rv;
 83
 84	rv = regmap_read(chip->map, MAX77650_REG_CNFG_GPIO, &val);
 85	if (rv)
 86		return rv;
 87
 88	return MAX77650_GPIO_INVAL_BITS(val);
 89}
 90
 91static int max77650_gpio_get_direction(struct gpio_chip *gc,
 92				       unsigned int offset)
 93{
 94	struct max77650_gpio_chip *chip = gpiochip_get_data(gc);
 95	unsigned int val;
 96	int rv;
 97
 98	rv = regmap_read(chip->map, MAX77650_REG_CNFG_GPIO, &val);
 99	if (rv)
100		return rv;
101
102	return MAX77650_GPIO_DIR_BITS(val);
103}
104
105static int max77650_gpio_set_config(struct gpio_chip *gc,
106				    unsigned int offset, unsigned long cfg)
107{
108	struct max77650_gpio_chip *chip = gpiochip_get_data(gc);
109
110	switch (pinconf_to_config_param(cfg)) {
111	case PIN_CONFIG_DRIVE_OPEN_DRAIN:
112		return regmap_update_bits(chip->map,
113					  MAX77650_REG_CNFG_GPIO,
114					  MAX77650_GPIO_DRV_MASK,
115					  MAX77650_GPIO_DRV_OPEN_DRAIN);
116	case PIN_CONFIG_DRIVE_PUSH_PULL:
117		return regmap_update_bits(chip->map,
118					  MAX77650_REG_CNFG_GPIO,
119					  MAX77650_GPIO_DRV_MASK,
120					  MAX77650_GPIO_DRV_PUSH_PULL);
121	case PIN_CONFIG_INPUT_DEBOUNCE:
122		return regmap_update_bits(chip->map,
123					  MAX77650_REG_CNFG_GPIO,
124					  MAX77650_GPIO_DEBOUNCE_MASK,
125					  MAX77650_GPIO_DEBOUNCE);
126	default:
127		return -ENOTSUPP;
128	}
129}
130
131static int max77650_gpio_to_irq(struct gpio_chip *gc, unsigned int offset)
132{
133	struct max77650_gpio_chip *chip = gpiochip_get_data(gc);
134
135	return chip->irq;
136}
137
138static int max77650_gpio_probe(struct platform_device *pdev)
139{
140	struct max77650_gpio_chip *chip;
141	struct device *dev, *parent;
142	struct i2c_client *i2c;
143
144	dev = &pdev->dev;
145	parent = dev->parent;
146	i2c = to_i2c_client(parent);
147
148	chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
149	if (!chip)
150		return -ENOMEM;
151
152	chip->map = dev_get_regmap(parent, NULL);
153	if (!chip->map)
154		return -ENODEV;
155
156	chip->irq = platform_get_irq_byname(pdev, "GPI");
157	if (chip->irq < 0)
158		return chip->irq;
159
160	chip->gc.base = -1;
161	chip->gc.ngpio = 1;
162	chip->gc.label = i2c->name;
163	chip->gc.parent = dev;
164	chip->gc.owner = THIS_MODULE;
165	chip->gc.can_sleep = true;
166
167	chip->gc.direction_input = max77650_gpio_direction_input;
168	chip->gc.direction_output = max77650_gpio_direction_output;
169	chip->gc.set = max77650_gpio_set_value;
170	chip->gc.get = max77650_gpio_get_value;
171	chip->gc.get_direction = max77650_gpio_get_direction;
172	chip->gc.set_config = max77650_gpio_set_config;
173	chip->gc.to_irq = max77650_gpio_to_irq;
174
175	return devm_gpiochip_add_data(dev, &chip->gc, chip);
176}
177
178static struct platform_driver max77650_gpio_driver = {
179	.driver = {
180		.name = "max77650-gpio",
181	},
182	.probe = max77650_gpio_probe,
183};
184module_platform_driver(max77650_gpio_driver);
185
186MODULE_DESCRIPTION("MAXIM 77650/77651 GPIO driver");
187MODULE_AUTHOR("Bartosz Golaszewski <bgolaszewski@baylibre.com>");
188MODULE_LICENSE("GPL v2");
189MODULE_ALIAS("platform:max77650-gpio");