xref: /openbmc/linux/drivers/gpio/gpio-arizona.c (revision 12eb4683)
1 /*
2  * gpiolib support for Wolfson Arizona class devices
3  *
4  * Copyright 2012 Wolfson Microelectronics PLC.
5  *
6  * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
7  *
8  *  This program is free software; you can redistribute  it and/or modify it
9  *  under  the terms of  the GNU General  Public License as published by the
10  *  Free Software Foundation;  either version 2 of the  License, or (at your
11  *  option) any later version.
12  *
13  */
14 
15 #include <linux/kernel.h>
16 #include <linux/slab.h>
17 #include <linux/module.h>
18 #include <linux/gpio.h>
19 #include <linux/platform_device.h>
20 #include <linux/seq_file.h>
21 
22 #include <linux/mfd/arizona/core.h>
23 #include <linux/mfd/arizona/pdata.h>
24 #include <linux/mfd/arizona/registers.h>
25 
26 struct arizona_gpio {
27 	struct arizona *arizona;
28 	struct gpio_chip gpio_chip;
29 };
30 
31 static inline struct arizona_gpio *to_arizona_gpio(struct gpio_chip *chip)
32 {
33 	return container_of(chip, struct arizona_gpio, gpio_chip);
34 }
35 
36 static int arizona_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
37 {
38 	struct arizona_gpio *arizona_gpio = to_arizona_gpio(chip);
39 	struct arizona *arizona = arizona_gpio->arizona;
40 
41 	return regmap_update_bits(arizona->regmap, ARIZONA_GPIO1_CTRL + offset,
42 				  ARIZONA_GPN_DIR, ARIZONA_GPN_DIR);
43 }
44 
45 static int arizona_gpio_get(struct gpio_chip *chip, unsigned offset)
46 {
47 	struct arizona_gpio *arizona_gpio = to_arizona_gpio(chip);
48 	struct arizona *arizona = arizona_gpio->arizona;
49 	unsigned int val;
50 	int ret;
51 
52 	ret = regmap_read(arizona->regmap, ARIZONA_GPIO1_CTRL + offset, &val);
53 	if (ret < 0)
54 		return ret;
55 
56 	if (val & ARIZONA_GPN_LVL)
57 		return 1;
58 	else
59 		return 0;
60 }
61 
62 static int arizona_gpio_direction_out(struct gpio_chip *chip,
63 				     unsigned offset, int value)
64 {
65 	struct arizona_gpio *arizona_gpio = to_arizona_gpio(chip);
66 	struct arizona *arizona = arizona_gpio->arizona;
67 
68 	if (value)
69 		value = ARIZONA_GPN_LVL;
70 
71 	return regmap_update_bits(arizona->regmap, ARIZONA_GPIO1_CTRL + offset,
72 				  ARIZONA_GPN_DIR | ARIZONA_GPN_LVL, value);
73 }
74 
75 static void arizona_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
76 {
77 	struct arizona_gpio *arizona_gpio = to_arizona_gpio(chip);
78 	struct arizona *arizona = arizona_gpio->arizona;
79 
80 	if (value)
81 		value = ARIZONA_GPN_LVL;
82 
83 	regmap_update_bits(arizona->regmap, ARIZONA_GPIO1_CTRL + offset,
84 			   ARIZONA_GPN_LVL, value);
85 }
86 
87 static struct gpio_chip template_chip = {
88 	.label			= "arizona",
89 	.owner			= THIS_MODULE,
90 	.direction_input	= arizona_gpio_direction_in,
91 	.get			= arizona_gpio_get,
92 	.direction_output	= arizona_gpio_direction_out,
93 	.set			= arizona_gpio_set,
94 	.can_sleep		= 1,
95 };
96 
97 static int arizona_gpio_probe(struct platform_device *pdev)
98 {
99 	struct arizona *arizona = dev_get_drvdata(pdev->dev.parent);
100 	struct arizona_pdata *pdata = dev_get_platdata(arizona->dev);
101 	struct arizona_gpio *arizona_gpio;
102 	int ret;
103 
104 	arizona_gpio = devm_kzalloc(&pdev->dev, sizeof(*arizona_gpio),
105 				    GFP_KERNEL);
106 	if (arizona_gpio == NULL)
107 		return -ENOMEM;
108 
109 	arizona_gpio->arizona = arizona;
110 	arizona_gpio->gpio_chip = template_chip;
111 	arizona_gpio->gpio_chip.dev = &pdev->dev;
112 #ifdef CONFIG_OF_GPIO
113 	arizona_gpio->gpio_chip.of_node = arizona->dev->of_node;
114 #endif
115 
116 	switch (arizona->type) {
117 	case WM5102:
118 	case WM5110:
119 	case WM8997:
120 		arizona_gpio->gpio_chip.ngpio = 5;
121 		break;
122 	default:
123 		dev_err(&pdev->dev, "Unknown chip variant %d\n",
124 			arizona->type);
125 		return -EINVAL;
126 	}
127 
128 	if (pdata && pdata->gpio_base)
129 		arizona_gpio->gpio_chip.base = pdata->gpio_base;
130 	else
131 		arizona_gpio->gpio_chip.base = -1;
132 
133 	ret = gpiochip_add(&arizona_gpio->gpio_chip);
134 	if (ret < 0) {
135 		dev_err(&pdev->dev, "Could not register gpiochip, %d\n",
136 			ret);
137 		goto err;
138 	}
139 
140 	platform_set_drvdata(pdev, arizona_gpio);
141 
142 	return ret;
143 
144 err:
145 	return ret;
146 }
147 
148 static int arizona_gpio_remove(struct platform_device *pdev)
149 {
150 	struct arizona_gpio *arizona_gpio = platform_get_drvdata(pdev);
151 
152 	return gpiochip_remove(&arizona_gpio->gpio_chip);
153 }
154 
155 static struct platform_driver arizona_gpio_driver = {
156 	.driver.name	= "arizona-gpio",
157 	.driver.owner	= THIS_MODULE,
158 	.probe		= arizona_gpio_probe,
159 	.remove		= arizona_gpio_remove,
160 };
161 
162 module_platform_driver(arizona_gpio_driver);
163 
164 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
165 MODULE_DESCRIPTION("GPIO interface for Arizona devices");
166 MODULE_LICENSE("GPL");
167 MODULE_ALIAS("platform:arizona-gpio");
168