1/*
  2 * GPIO driver for RICOH583 power management chip.
  3 *
  4 * Copyright (c) 2012, NVIDIA CORPORATION.  All rights reserved.
  5 * Author: Laxman dewangan <ldewangan@nvidia.com>
  6 *
  7 * Based on code
  8 *	Copyright (C) 2011 RICOH COMPANY,LTD
  9 *
 10 * This program is free software; you can redistribute it and/or modify it
 11 * under the terms and conditions of the GNU General Public License,
 12 * version 2, as published by the Free Software Foundation.
 13 *
 14 * This program is distributed in the hope it will be useful, but WITHOUT
 15 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 16 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 17 * more details.
 18 *
 19 * You should have received a copy of the GNU General Public License
 20 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 21 *
 22 */
 23#include <linux/init.h>
 24#include <linux/kernel.h>
 25#include <linux/slab.h>
 26#include <linux/module.h>
 27#include <linux/platform_device.h>
 28#include <linux/device.h>
 29#include <linux/gpio.h>
 30#include <linux/mfd/rc5t583.h>
 31
 32struct rc5t583_gpio {
 33	struct gpio_chip gpio_chip;
 34	struct rc5t583 *rc5t583;
 35};
 36
 37static int rc5t583_gpio_get(struct gpio_chip *gc, unsigned int offset)
 38{
 39	struct rc5t583_gpio *rc5t583_gpio = gpiochip_get_data(gc);
 40	struct device *parent = rc5t583_gpio->rc5t583->dev;
 41	uint8_t val = 0;
 42	int ret;
 43
 44	ret = rc5t583_read(parent, RC5T583_GPIO_MON_IOIN, &val);
 45	if (ret < 0)
 46		return ret;
 47
 48	return !!(val & BIT(offset));
 49}
 50
 51static void rc5t583_gpio_set(struct gpio_chip *gc, unsigned int offset, int val)
 52{
 53	struct rc5t583_gpio *rc5t583_gpio = gpiochip_get_data(gc);
 54	struct device *parent = rc5t583_gpio->rc5t583->dev;
 55	if (val)
 56		rc5t583_set_bits(parent, RC5T583_GPIO_IOOUT, BIT(offset));
 57	else
 58		rc5t583_clear_bits(parent, RC5T583_GPIO_IOOUT, BIT(offset));
 59}
 60
 61static int rc5t583_gpio_dir_input(struct gpio_chip *gc, unsigned int offset)
 62{
 63	struct rc5t583_gpio *rc5t583_gpio = gpiochip_get_data(gc);
 64	struct device *parent = rc5t583_gpio->rc5t583->dev;
 65	int ret;
 66
 67	ret = rc5t583_clear_bits(parent, RC5T583_GPIO_IOSEL, BIT(offset));
 68	if (ret < 0)
 69		return ret;
 70
 71	/* Set pin to gpio mode */
 72	return rc5t583_clear_bits(parent, RC5T583_GPIO_PGSEL, BIT(offset));
 73}
 74
 75static int rc5t583_gpio_dir_output(struct gpio_chip *gc, unsigned offset,
 76			int value)
 77{
 78	struct rc5t583_gpio *rc5t583_gpio = gpiochip_get_data(gc);
 79	struct device *parent = rc5t583_gpio->rc5t583->dev;
 80	int ret;
 81
 82	rc5t583_gpio_set(gc, offset, value);
 83	ret = rc5t583_set_bits(parent, RC5T583_GPIO_IOSEL, BIT(offset));
 84	if (ret < 0)
 85		return ret;
 86
 87	/* Set pin to gpio mode */
 88	return rc5t583_clear_bits(parent, RC5T583_GPIO_PGSEL, BIT(offset));
 89}
 90
 91static int rc5t583_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
 92{
 93	struct rc5t583_gpio *rc5t583_gpio = gpiochip_get_data(gc);
 94
 95	if (offset < RC5T583_MAX_GPIO)
 96		return rc5t583_gpio->rc5t583->irq_base +
 97				RC5T583_IRQ_GPIO0 + offset;
 98	return -EINVAL;
 99}
100
101static void rc5t583_gpio_free(struct gpio_chip *gc, unsigned offset)
102{
103	struct rc5t583_gpio *rc5t583_gpio = gpiochip_get_data(gc);
104	struct device *parent = rc5t583_gpio->rc5t583->dev;
105
106	rc5t583_set_bits(parent, RC5T583_GPIO_PGSEL, BIT(offset));
107}
108
109static int rc5t583_gpio_probe(struct platform_device *pdev)
110{
111	struct rc5t583 *rc5t583 = dev_get_drvdata(pdev->dev.parent);
112	struct rc5t583_platform_data *pdata = dev_get_platdata(rc5t583->dev);
113	struct rc5t583_gpio *rc5t583_gpio;
114
115	rc5t583_gpio = devm_kzalloc(&pdev->dev, sizeof(*rc5t583_gpio),
116					GFP_KERNEL);
117	if (!rc5t583_gpio)
118		return -ENOMEM;
119
120	rc5t583_gpio->gpio_chip.label = "gpio-rc5t583",
121	rc5t583_gpio->gpio_chip.owner = THIS_MODULE,
122	rc5t583_gpio->gpio_chip.free = rc5t583_gpio_free,
123	rc5t583_gpio->gpio_chip.direction_input = rc5t583_gpio_dir_input,
124	rc5t583_gpio->gpio_chip.direction_output = rc5t583_gpio_dir_output,
125	rc5t583_gpio->gpio_chip.set = rc5t583_gpio_set,
126	rc5t583_gpio->gpio_chip.get = rc5t583_gpio_get,
127	rc5t583_gpio->gpio_chip.to_irq = rc5t583_gpio_to_irq,
128	rc5t583_gpio->gpio_chip.ngpio = RC5T583_MAX_GPIO,
129	rc5t583_gpio->gpio_chip.can_sleep = true,
130	rc5t583_gpio->gpio_chip.parent = &pdev->dev;
131	rc5t583_gpio->gpio_chip.base = -1;
132	rc5t583_gpio->rc5t583 = rc5t583;
133
134	if (pdata && pdata->gpio_base)
135		rc5t583_gpio->gpio_chip.base = pdata->gpio_base;
136
137	platform_set_drvdata(pdev, rc5t583_gpio);
138
139	return devm_gpiochip_add_data(&pdev->dev, &rc5t583_gpio->gpio_chip,
140				      rc5t583_gpio);
141}
142
143static struct platform_driver rc5t583_gpio_driver = {
144	.driver = {
145		.name    = "rc5t583-gpio",
146	},
147	.probe		= rc5t583_gpio_probe,
148};
149
150static int __init rc5t583_gpio_init(void)
151{
152	return platform_driver_register(&rc5t583_gpio_driver);
153}
154subsys_initcall(rc5t583_gpio_init);
155
156static void __exit rc5t583_gpio_exit(void)
157{
158	platform_driver_unregister(&rc5t583_gpio_driver);
159}
160module_exit(rc5t583_gpio_exit);
161
162MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
163MODULE_DESCRIPTION("GPIO interface for RC5T583");
164MODULE_LICENSE("GPL v2");
165MODULE_ALIAS("platform:rc5t583-gpio");