xref: /openbmc/linux/drivers/gpio/gpio-max77650.c (revision 976e3645923bdd2fe7893aae33fd7a21098bfb28)
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  
34  struct max77650_gpio_chip {
35  	struct regmap *map;
36  	struct gpio_chip gc;
37  	int irq;
38  };
39  
max77650_gpio_direction_input(struct gpio_chip * gc,unsigned int offset)40  static 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  
max77650_gpio_direction_output(struct gpio_chip * gc,unsigned int offset,int value)51  static 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  
max77650_gpio_set_value(struct gpio_chip * gc,unsigned int offset,int value)65  static void 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 rv, regval;
70  
71  	regval = value ? MAX77650_GPIO_OUT_HIGH : MAX77650_GPIO_OUT_LOW;
72  
73  	rv = regmap_update_bits(chip->map, MAX77650_REG_CNFG_GPIO,
74  				MAX77650_GPIO_OUTVAL_MASK, regval);
75  	if (rv)
76  		dev_err(gc->parent, "cannot set GPIO value: %d\n", rv);
77  }
78  
max77650_gpio_get_value(struct gpio_chip * gc,unsigned int offset)79  static int max77650_gpio_get_value(struct gpio_chip *gc,
80  				   unsigned int offset)
81  {
82  	struct max77650_gpio_chip *chip = gpiochip_get_data(gc);
83  	unsigned int val;
84  	int rv;
85  
86  	rv = regmap_read(chip->map, MAX77650_REG_CNFG_GPIO, &val);
87  	if (rv)
88  		return rv;
89  
90  	return MAX77650_GPIO_INVAL_BITS(val);
91  }
92  
max77650_gpio_get_direction(struct gpio_chip * gc,unsigned int offset)93  static int max77650_gpio_get_direction(struct gpio_chip *gc,
94  				       unsigned int offset)
95  {
96  	struct max77650_gpio_chip *chip = gpiochip_get_data(gc);
97  	unsigned int val;
98  	int rv;
99  
100  	rv = regmap_read(chip->map, MAX77650_REG_CNFG_GPIO, &val);
101  	if (rv)
102  		return rv;
103  
104  	return MAX77650_GPIO_DIR_BITS(val);
105  }
106  
max77650_gpio_set_config(struct gpio_chip * gc,unsigned int offset,unsigned long cfg)107  static int max77650_gpio_set_config(struct gpio_chip *gc,
108  				    unsigned int offset, unsigned long cfg)
109  {
110  	struct max77650_gpio_chip *chip = gpiochip_get_data(gc);
111  
112  	switch (pinconf_to_config_param(cfg)) {
113  	case PIN_CONFIG_DRIVE_OPEN_DRAIN:
114  		return regmap_update_bits(chip->map,
115  					  MAX77650_REG_CNFG_GPIO,
116  					  MAX77650_GPIO_DRV_MASK,
117  					  MAX77650_GPIO_DRV_OPEN_DRAIN);
118  	case PIN_CONFIG_DRIVE_PUSH_PULL:
119  		return regmap_update_bits(chip->map,
120  					  MAX77650_REG_CNFG_GPIO,
121  					  MAX77650_GPIO_DRV_MASK,
122  					  MAX77650_GPIO_DRV_PUSH_PULL);
123  	case PIN_CONFIG_INPUT_DEBOUNCE:
124  		return regmap_update_bits(chip->map,
125  					  MAX77650_REG_CNFG_GPIO,
126  					  MAX77650_GPIO_DEBOUNCE_MASK,
127  					  MAX77650_GPIO_DEBOUNCE);
128  	default:
129  		return -ENOTSUPP;
130  	}
131  }
132  
max77650_gpio_to_irq(struct gpio_chip * gc,unsigned int offset)133  static int max77650_gpio_to_irq(struct gpio_chip *gc, unsigned int offset)
134  {
135  	struct max77650_gpio_chip *chip = gpiochip_get_data(gc);
136  
137  	return chip->irq;
138  }
139  
max77650_gpio_probe(struct platform_device * pdev)140  static int max77650_gpio_probe(struct platform_device *pdev)
141  {
142  	struct max77650_gpio_chip *chip;
143  	struct device *dev, *parent;
144  	struct i2c_client *i2c;
145  
146  	dev = &pdev->dev;
147  	parent = dev->parent;
148  	i2c = to_i2c_client(parent);
149  
150  	chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
151  	if (!chip)
152  		return -ENOMEM;
153  
154  	chip->map = dev_get_regmap(parent, NULL);
155  	if (!chip->map)
156  		return -ENODEV;
157  
158  	chip->irq = platform_get_irq_byname(pdev, "GPI");
159  	if (chip->irq < 0)
160  		return chip->irq;
161  
162  	chip->gc.base = -1;
163  	chip->gc.ngpio = 1;
164  	chip->gc.label = i2c->name;
165  	chip->gc.parent = dev;
166  	chip->gc.owner = THIS_MODULE;
167  	chip->gc.can_sleep = true;
168  
169  	chip->gc.direction_input = max77650_gpio_direction_input;
170  	chip->gc.direction_output = max77650_gpio_direction_output;
171  	chip->gc.set = max77650_gpio_set_value;
172  	chip->gc.get = max77650_gpio_get_value;
173  	chip->gc.get_direction = max77650_gpio_get_direction;
174  	chip->gc.set_config = max77650_gpio_set_config;
175  	chip->gc.to_irq = max77650_gpio_to_irq;
176  
177  	return devm_gpiochip_add_data(dev, &chip->gc, chip);
178  }
179  
180  static struct platform_driver max77650_gpio_driver = {
181  	.driver = {
182  		.name = "max77650-gpio",
183  	},
184  	.probe = max77650_gpio_probe,
185  };
186  module_platform_driver(max77650_gpio_driver);
187  
188  MODULE_DESCRIPTION("MAXIM 77650/77651 GPIO driver");
189  MODULE_AUTHOR("Bartosz Golaszewski <bgolaszewski@baylibre.com>");
190  MODULE_LICENSE("GPL v2");
191  MODULE_ALIAS("platform:max77650-gpio");
192