1/*
2 * GPIO Driver for Dialog DA9055 PMICs.
3 *
4 * Copyright(c) 2012 Dialog Semiconductor Ltd.
5 *
6 * Author: David Dajun Chen <dchen@diasemi.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#include <linux/module.h>
15#include <linux/platform_device.h>
16#include <linux/gpio.h>
17
18#include <linux/mfd/da9055/core.h>
19#include <linux/mfd/da9055/reg.h>
20#include <linux/mfd/da9055/pdata.h>
21
22#define DA9055_VDD_IO			0x0
23#define DA9055_PUSH_PULL		0x3
24#define DA9055_ACT_LOW			0x0
25#define DA9055_GPI			0x1
26#define DA9055_PORT_MASK		0x3
27#define DA9055_PORT_SHIFT(offset)	(4 * (offset % 2))
28
29#define DA9055_INPUT			DA9055_GPI
30#define DA9055_OUTPUT			DA9055_PUSH_PULL
31#define DA9055_IRQ_GPI0			3
32
33struct da9055_gpio {
34	struct da9055 *da9055;
35	struct gpio_chip gp;
36};
37
38static inline struct da9055_gpio *to_da9055_gpio(struct gpio_chip *chip)
39{
40	return container_of(chip, struct da9055_gpio, gp);
41}
42
43static int da9055_gpio_get(struct gpio_chip *gc, unsigned offset)
44{
45	struct da9055_gpio *gpio = to_da9055_gpio(gc);
46	int gpio_direction = 0;
47	int ret;
48
49	/* Get GPIO direction */
50	ret = da9055_reg_read(gpio->da9055, (offset >> 1) + DA9055_REG_GPIO0_1);
51	if (ret < 0)
52		return ret;
53
54	gpio_direction = ret & (DA9055_PORT_MASK) << DA9055_PORT_SHIFT(offset);
55	gpio_direction >>= DA9055_PORT_SHIFT(offset);
56	switch (gpio_direction) {
57	case DA9055_INPUT:
58		ret = da9055_reg_read(gpio->da9055, DA9055_REG_STATUS_B);
59		if (ret < 0)
60			return ret;
61		break;
62	case DA9055_OUTPUT:
63		ret = da9055_reg_read(gpio->da9055, DA9055_REG_GPIO_MODE0_2);
64		if (ret < 0)
65			return ret;
66	}
67
68	return ret & (1 << offset);
69
70}
71
72static void da9055_gpio_set(struct gpio_chip *gc, unsigned offset, int value)
73{
74	struct da9055_gpio *gpio = to_da9055_gpio(gc);
75
76	da9055_reg_update(gpio->da9055,
77			DA9055_REG_GPIO_MODE0_2,
78			1 << offset,
79			value << offset);
80}
81
82static int da9055_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
83{
84	struct da9055_gpio *gpio = to_da9055_gpio(gc);
85	unsigned char reg_byte;
86
87	reg_byte = (DA9055_ACT_LOW | DA9055_GPI)
88				<< DA9055_PORT_SHIFT(offset);
89
90	return da9055_reg_update(gpio->da9055, (offset >> 1) +
91				DA9055_REG_GPIO0_1,
92				DA9055_PORT_MASK <<
93				DA9055_PORT_SHIFT(offset),
94				reg_byte);
95}
96
97static int da9055_gpio_direction_output(struct gpio_chip *gc,
98					unsigned offset, int value)
99{
100	struct da9055_gpio *gpio = to_da9055_gpio(gc);
101	unsigned char reg_byte;
102	int ret;
103
104	reg_byte = (DA9055_VDD_IO | DA9055_PUSH_PULL)
105					<< DA9055_PORT_SHIFT(offset);
106
107	ret = da9055_reg_update(gpio->da9055, (offset >> 1) +
108				DA9055_REG_GPIO0_1,
109				DA9055_PORT_MASK <<
110				DA9055_PORT_SHIFT(offset),
111				reg_byte);
112	if (ret < 0)
113		return ret;
114
115	da9055_gpio_set(gc, offset, value);
116
117	return 0;
118}
119
120static int da9055_gpio_to_irq(struct gpio_chip *gc, u32 offset)
121{
122	struct da9055_gpio *gpio = to_da9055_gpio(gc);
123	struct da9055 *da9055 = gpio->da9055;
124
125	return regmap_irq_get_virq(da9055->irq_data,
126				  DA9055_IRQ_GPI0 + offset);
127}
128
129static struct gpio_chip reference_gp = {
130	.label = "da9055-gpio",
131	.owner = THIS_MODULE,
132	.get = da9055_gpio_get,
133	.set = da9055_gpio_set,
134	.direction_input = da9055_gpio_direction_input,
135	.direction_output = da9055_gpio_direction_output,
136	.to_irq = da9055_gpio_to_irq,
137	.can_sleep = true,
138	.ngpio = 3,
139	.base = -1,
140};
141
142static int da9055_gpio_probe(struct platform_device *pdev)
143{
144	struct da9055_gpio *gpio;
145	struct da9055_pdata *pdata;
146	int ret;
147
148	gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
149	if (!gpio)
150		return -ENOMEM;
151
152	gpio->da9055 = dev_get_drvdata(pdev->dev.parent);
153	pdata = dev_get_platdata(gpio->da9055->dev);
154
155	gpio->gp = reference_gp;
156	if (pdata && pdata->gpio_base)
157		gpio->gp.base = pdata->gpio_base;
158
159	ret = gpiochip_add(&gpio->gp);
160	if (ret < 0) {
161		dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
162		goto err_mem;
163	}
164
165	platform_set_drvdata(pdev, gpio);
166
167	return 0;
168
169err_mem:
170	return ret;
171}
172
173static int da9055_gpio_remove(struct platform_device *pdev)
174{
175	struct da9055_gpio *gpio = platform_get_drvdata(pdev);
176
177	gpiochip_remove(&gpio->gp);
178	return 0;
179}
180
181static struct platform_driver da9055_gpio_driver = {
182	.probe = da9055_gpio_probe,
183	.remove = da9055_gpio_remove,
184	.driver = {
185		.name	= "da9055-gpio",
186	},
187};
188
189static int __init da9055_gpio_init(void)
190{
191	return platform_driver_register(&da9055_gpio_driver);
192}
193subsys_initcall(da9055_gpio_init);
194
195static void __exit da9055_gpio_exit(void)
196{
197	platform_driver_unregister(&da9055_gpio_driver);
198}
199module_exit(da9055_gpio_exit);
200
201MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
202MODULE_DESCRIPTION("DA9055 GPIO Device Driver");
203MODULE_LICENSE("GPL");
204MODULE_ALIAS("platform:da9055-gpio");
205