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
26struct arizona_gpio {
27	struct arizona *arizona;
28	struct gpio_chip gpio_chip;
29};
30
31static inline struct arizona_gpio *to_arizona_gpio(struct gpio_chip *chip)
32{
33	return container_of(chip, struct arizona_gpio, gpio_chip);
34}
35
36static 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
45static 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
62static 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
75static 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
87static 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		= true,
95};
96
97static 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)
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 WM8280:
120	case WM8997:
121		arizona_gpio->gpio_chip.ngpio = 5;
122		break;
123	default:
124		dev_err(&pdev->dev, "Unknown chip variant %d\n",
125			arizona->type);
126		return -EINVAL;
127	}
128
129	if (pdata && pdata->gpio_base)
130		arizona_gpio->gpio_chip.base = pdata->gpio_base;
131	else
132		arizona_gpio->gpio_chip.base = -1;
133
134	ret = gpiochip_add(&arizona_gpio->gpio_chip);
135	if (ret < 0) {
136		dev_err(&pdev->dev, "Could not register gpiochip, %d\n",
137			ret);
138		goto err;
139	}
140
141	platform_set_drvdata(pdev, arizona_gpio);
142
143	return ret;
144
145err:
146	return ret;
147}
148
149static int arizona_gpio_remove(struct platform_device *pdev)
150{
151	struct arizona_gpio *arizona_gpio = platform_get_drvdata(pdev);
152
153	gpiochip_remove(&arizona_gpio->gpio_chip);
154	return 0;
155}
156
157static struct platform_driver arizona_gpio_driver = {
158	.driver.name	= "arizona-gpio",
159	.probe		= arizona_gpio_probe,
160	.remove		= arizona_gpio_remove,
161};
162
163module_platform_driver(arizona_gpio_driver);
164
165MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
166MODULE_DESCRIPTION("GPIO interface for Arizona devices");
167MODULE_LICENSE("GPL");
168MODULE_ALIAS("platform:arizona-gpio");
169