1/*
2 * TI TPS6586x GPIO driver
3 *
4 * Copyright (c) 2012, NVIDIA CORPORATION.  All rights reserved.
5 * Author: Laxman dewangan <ldewangan@nvidia.com>
6 *
7 * Based on tps6586x.c
8 * Copyright (c) 2010 CompuLab Ltd.
9 * Mike Rapoport <mike@compulab.co.il>
10 *
11 * This program is free software; you can redistribute it and/or modify it
12 * under the terms and conditions of the GNU General Public License,
13 * version 2, as published by the Free Software Foundation.
14 *
15 * This program is distributed in the hope it will be useful, but WITHOUT
16 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
17 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
18 * more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
22 */
23
24#include <linux/errno.h>
25#include <linux/gpio.h>
26#include <linux/kernel.h>
27#include <linux/module.h>
28#include <linux/mfd/tps6586x.h>
29#include <linux/of_device.h>
30#include <linux/platform_device.h>
31
32/* GPIO control registers */
33#define TPS6586X_GPIOSET1	0x5d
34#define TPS6586X_GPIOSET2	0x5e
35
36struct tps6586x_gpio {
37	struct gpio_chip gpio_chip;
38	struct device *parent;
39};
40
41static inline struct tps6586x_gpio *to_tps6586x_gpio(struct gpio_chip *chip)
42{
43	return container_of(chip, struct tps6586x_gpio, gpio_chip);
44}
45
46static int tps6586x_gpio_get(struct gpio_chip *gc, unsigned offset)
47{
48	struct tps6586x_gpio *tps6586x_gpio = to_tps6586x_gpio(gc);
49	uint8_t val;
50	int ret;
51
52	ret = tps6586x_read(tps6586x_gpio->parent, TPS6586X_GPIOSET2, &val);
53	if (ret)
54		return ret;
55
56	return !!(val & (1 << offset));
57}
58
59static void tps6586x_gpio_set(struct gpio_chip *gc, unsigned offset,
60			      int value)
61{
62	struct tps6586x_gpio *tps6586x_gpio = to_tps6586x_gpio(gc);
63
64	tps6586x_update(tps6586x_gpio->parent, TPS6586X_GPIOSET2,
65			value << offset, 1 << offset);
66}
67
68static int tps6586x_gpio_output(struct gpio_chip *gc, unsigned offset,
69				int value)
70{
71	struct tps6586x_gpio *tps6586x_gpio = to_tps6586x_gpio(gc);
72	uint8_t val, mask;
73
74	tps6586x_gpio_set(gc, offset, value);
75
76	val = 0x1 << (offset * 2);
77	mask = 0x3 << (offset * 2);
78
79	return tps6586x_update(tps6586x_gpio->parent, TPS6586X_GPIOSET1,
80				val, mask);
81}
82
83static int tps6586x_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
84{
85	struct tps6586x_gpio *tps6586x_gpio = to_tps6586x_gpio(gc);
86
87	return tps6586x_irq_get_virq(tps6586x_gpio->parent,
88				TPS6586X_INT_PLDO_0 + offset);
89}
90
91static int tps6586x_gpio_probe(struct platform_device *pdev)
92{
93	struct tps6586x_platform_data *pdata;
94	struct tps6586x_gpio *tps6586x_gpio;
95	int ret;
96
97	pdata = dev_get_platdata(pdev->dev.parent);
98	tps6586x_gpio = devm_kzalloc(&pdev->dev,
99				sizeof(*tps6586x_gpio), GFP_KERNEL);
100	if (!tps6586x_gpio)
101		return -ENOMEM;
102
103	tps6586x_gpio->parent = pdev->dev.parent;
104
105	tps6586x_gpio->gpio_chip.owner = THIS_MODULE;
106	tps6586x_gpio->gpio_chip.label = pdev->name;
107	tps6586x_gpio->gpio_chip.dev = &pdev->dev;
108	tps6586x_gpio->gpio_chip.ngpio = 4;
109	tps6586x_gpio->gpio_chip.can_sleep = true;
110
111	/* FIXME: add handling of GPIOs as dedicated inputs */
112	tps6586x_gpio->gpio_chip.direction_output = tps6586x_gpio_output;
113	tps6586x_gpio->gpio_chip.set	= tps6586x_gpio_set;
114	tps6586x_gpio->gpio_chip.get	= tps6586x_gpio_get;
115	tps6586x_gpio->gpio_chip.to_irq	= tps6586x_gpio_to_irq;
116
117#ifdef CONFIG_OF_GPIO
118	tps6586x_gpio->gpio_chip.of_node = pdev->dev.parent->of_node;
119#endif
120	if (pdata && pdata->gpio_base)
121		tps6586x_gpio->gpio_chip.base = pdata->gpio_base;
122	else
123		tps6586x_gpio->gpio_chip.base = -1;
124
125	ret = gpiochip_add(&tps6586x_gpio->gpio_chip);
126	if (ret < 0) {
127		dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
128		return ret;
129	}
130
131	platform_set_drvdata(pdev, tps6586x_gpio);
132
133	return ret;
134}
135
136static int tps6586x_gpio_remove(struct platform_device *pdev)
137{
138	struct tps6586x_gpio *tps6586x_gpio = platform_get_drvdata(pdev);
139
140	gpiochip_remove(&tps6586x_gpio->gpio_chip);
141	return 0;
142}
143
144static struct platform_driver tps6586x_gpio_driver = {
145	.driver.name	= "tps6586x-gpio",
146	.driver.owner	= THIS_MODULE,
147	.probe		= tps6586x_gpio_probe,
148	.remove		= tps6586x_gpio_remove,
149};
150
151static int __init tps6586x_gpio_init(void)
152{
153	return platform_driver_register(&tps6586x_gpio_driver);
154}
155subsys_initcall(tps6586x_gpio_init);
156
157static void __exit tps6586x_gpio_exit(void)
158{
159	platform_driver_unregister(&tps6586x_gpio_driver);
160}
161module_exit(tps6586x_gpio_exit);
162
163MODULE_ALIAS("platform:tps6586x-gpio");
164MODULE_DESCRIPTION("GPIO interface for TPS6586X PMIC");
165MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
166MODULE_LICENSE("GPL");
167