1 /*
2  * ROHM BD9571MWV-M GPIO driver
3  *
4  * Copyright (C) 2017 Marek Vasut <marek.vasut+renesas@gmail.com>
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  *
10  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
11  * kind, whether expressed or implied; without even the implied warranty
12  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License version 2 for more details.
14  *
15  * Based on the TPS65086 driver
16  *
17  * NOTE: Interrupts are not supported yet.
18  */
19 
20 #include <linux/gpio/driver.h>
21 #include <linux/module.h>
22 #include <linux/platform_device.h>
23 
24 #include <linux/mfd/bd9571mwv.h>
25 
26 struct bd9571mwv_gpio {
27 	struct gpio_chip chip;
28 	struct bd9571mwv *bd;
29 };
30 
bd9571mwv_gpio_get_direction(struct gpio_chip * chip,unsigned int offset)31 static int bd9571mwv_gpio_get_direction(struct gpio_chip *chip,
32 				       unsigned int offset)
33 {
34 	struct bd9571mwv_gpio *gpio = gpiochip_get_data(chip);
35 	int ret, val;
36 
37 	ret = regmap_read(gpio->bd->regmap, BD9571MWV_GPIO_DIR, &val);
38 	if (ret < 0)
39 		return ret;
40 
41 	return val & BIT(offset);
42 }
43 
bd9571mwv_gpio_direction_input(struct gpio_chip * chip,unsigned int offset)44 static int bd9571mwv_gpio_direction_input(struct gpio_chip *chip,
45 					 unsigned int offset)
46 {
47 	struct bd9571mwv_gpio *gpio = gpiochip_get_data(chip);
48 
49 	regmap_update_bits(gpio->bd->regmap, BD9571MWV_GPIO_DIR,
50 			   BIT(offset), 0);
51 
52 	return 0;
53 }
54 
bd9571mwv_gpio_direction_output(struct gpio_chip * chip,unsigned int offset,int value)55 static int bd9571mwv_gpio_direction_output(struct gpio_chip *chip,
56 					  unsigned int offset, int value)
57 {
58 	struct bd9571mwv_gpio *gpio = gpiochip_get_data(chip);
59 
60 	/* Set the initial value */
61 	regmap_update_bits(gpio->bd->regmap, BD9571MWV_GPIO_OUT,
62 			   BIT(offset), value ? BIT(offset) : 0);
63 	regmap_update_bits(gpio->bd->regmap, BD9571MWV_GPIO_DIR,
64 			   BIT(offset), BIT(offset));
65 
66 	return 0;
67 }
68 
bd9571mwv_gpio_get(struct gpio_chip * chip,unsigned int offset)69 static int bd9571mwv_gpio_get(struct gpio_chip *chip, unsigned int offset)
70 {
71 	struct bd9571mwv_gpio *gpio = gpiochip_get_data(chip);
72 	int ret, val;
73 
74 	ret = regmap_read(gpio->bd->regmap, BD9571MWV_GPIO_IN, &val);
75 	if (ret < 0)
76 		return ret;
77 
78 	return val & BIT(offset);
79 }
80 
bd9571mwv_gpio_set(struct gpio_chip * chip,unsigned int offset,int value)81 static void bd9571mwv_gpio_set(struct gpio_chip *chip, unsigned int offset,
82 			      int value)
83 {
84 	struct bd9571mwv_gpio *gpio = gpiochip_get_data(chip);
85 
86 	regmap_update_bits(gpio->bd->regmap, BD9571MWV_GPIO_OUT,
87 			   BIT(offset), value ? BIT(offset) : 0);
88 }
89 
90 static const struct gpio_chip template_chip = {
91 	.label			= "bd9571mwv-gpio",
92 	.owner			= THIS_MODULE,
93 	.get_direction		= bd9571mwv_gpio_get_direction,
94 	.direction_input	= bd9571mwv_gpio_direction_input,
95 	.direction_output	= bd9571mwv_gpio_direction_output,
96 	.get			= bd9571mwv_gpio_get,
97 	.set			= bd9571mwv_gpio_set,
98 	.base			= -1,
99 	.ngpio			= 2,
100 	.can_sleep		= true,
101 };
102 
bd9571mwv_gpio_probe(struct platform_device * pdev)103 static int bd9571mwv_gpio_probe(struct platform_device *pdev)
104 {
105 	struct bd9571mwv_gpio *gpio;
106 	int ret;
107 
108 	gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
109 	if (!gpio)
110 		return -ENOMEM;
111 
112 	platform_set_drvdata(pdev, gpio);
113 
114 	gpio->bd = dev_get_drvdata(pdev->dev.parent);
115 	gpio->chip = template_chip;
116 	gpio->chip.parent = gpio->bd->dev;
117 
118 	ret = devm_gpiochip_add_data(&pdev->dev, &gpio->chip, gpio);
119 	if (ret < 0) {
120 		dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
121 		return ret;
122 	}
123 
124 	return 0;
125 }
126 
127 static const struct platform_device_id bd9571mwv_gpio_id_table[] = {
128 	{ "bd9571mwv-gpio", },
129 	{ /* sentinel */ }
130 };
131 MODULE_DEVICE_TABLE(platform, bd9571mwv_gpio_id_table);
132 
133 static struct platform_driver bd9571mwv_gpio_driver = {
134 	.driver = {
135 		.name = "bd9571mwv-gpio",
136 	},
137 	.probe = bd9571mwv_gpio_probe,
138 	.id_table = bd9571mwv_gpio_id_table,
139 };
140 module_platform_driver(bd9571mwv_gpio_driver);
141 
142 MODULE_AUTHOR("Marek Vasut <marek.vasut+renesas@gmail.com>");
143 MODULE_DESCRIPTION("BD9571MWV GPIO driver");
144 MODULE_LICENSE("GPL v2");
145