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 inline struct rc5t583_gpio *to_rc5t583_gpio(struct gpio_chip *chip)
 38{
 39	return container_of(chip, struct rc5t583_gpio, gpio_chip);
 40}
 41
 42static int rc5t583_gpio_get(struct gpio_chip *gc, unsigned int offset)
 43{
 44	struct rc5t583_gpio *rc5t583_gpio = to_rc5t583_gpio(gc);
 45	struct device *parent = rc5t583_gpio->rc5t583->dev;
 46	uint8_t val = 0;
 47	int ret;
 48
 49	ret = rc5t583_read(parent, RC5T583_GPIO_MON_IOIN, &val);
 50	if (ret < 0)
 51		return ret;
 52
 53	return !!(val & BIT(offset));
 54}
 55
 56static void rc5t583_gpio_set(struct gpio_chip *gc, unsigned int offset, int val)
 57{
 58	struct rc5t583_gpio *rc5t583_gpio = to_rc5t583_gpio(gc);
 59	struct device *parent = rc5t583_gpio->rc5t583->dev;
 60	if (val)
 61		rc5t583_set_bits(parent, RC5T583_GPIO_IOOUT, BIT(offset));
 62	else
 63		rc5t583_clear_bits(parent, RC5T583_GPIO_IOOUT, BIT(offset));
 64}
 65
 66static int rc5t583_gpio_dir_input(struct gpio_chip *gc, unsigned int offset)
 67{
 68	struct rc5t583_gpio *rc5t583_gpio = to_rc5t583_gpio(gc);
 69	struct device *parent = rc5t583_gpio->rc5t583->dev;
 70	int ret;
 71
 72	ret = rc5t583_clear_bits(parent, RC5T583_GPIO_IOSEL, BIT(offset));
 73	if (ret < 0)
 74		return ret;
 75
 76	/* Set pin to gpio mode */
 77	return rc5t583_clear_bits(parent, RC5T583_GPIO_PGSEL, BIT(offset));
 78}
 79
 80static int rc5t583_gpio_dir_output(struct gpio_chip *gc, unsigned offset,
 81			int value)
 82{
 83	struct rc5t583_gpio *rc5t583_gpio = to_rc5t583_gpio(gc);
 84	struct device *parent = rc5t583_gpio->rc5t583->dev;
 85	int ret;
 86
 87	rc5t583_gpio_set(gc, offset, value);
 88	ret = rc5t583_set_bits(parent, RC5T583_GPIO_IOSEL, BIT(offset));
 89	if (ret < 0)
 90		return ret;
 91
 92	/* Set pin to gpio mode */
 93	return rc5t583_clear_bits(parent, RC5T583_GPIO_PGSEL, BIT(offset));
 94}
 95
 96static int rc5t583_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
 97{
 98	struct rc5t583_gpio *rc5t583_gpio = to_rc5t583_gpio(gc);
 99
100	if ((offset >= 0) && (offset < 8))
101		return rc5t583_gpio->rc5t583->irq_base +
102				RC5T583_IRQ_GPIO0 + offset;
103	return -EINVAL;
104}
105
106static void rc5t583_gpio_free(struct gpio_chip *gc, unsigned offset)
107{
108	struct rc5t583_gpio *rc5t583_gpio = to_rc5t583_gpio(gc);
109	struct device *parent = rc5t583_gpio->rc5t583->dev;
110
111	rc5t583_set_bits(parent, RC5T583_GPIO_PGSEL, BIT(offset));
112}
113
114static int __devinit rc5t583_gpio_probe(struct platform_device *pdev)
115{
116	struct rc5t583 *rc5t583 = dev_get_drvdata(pdev->dev.parent);
117	struct rc5t583_platform_data *pdata = dev_get_platdata(rc5t583->dev);
118	struct rc5t583_gpio *rc5t583_gpio;
119
120	rc5t583_gpio = devm_kzalloc(&pdev->dev, sizeof(*rc5t583_gpio),
121					GFP_KERNEL);
122	if (!rc5t583_gpio) {
123		dev_warn(&pdev->dev, "Mem allocation for rc5t583_gpio failed");
124		return -ENOMEM;
125	}
126
127	rc5t583_gpio->gpio_chip.label = "gpio-rc5t583",
128	rc5t583_gpio->gpio_chip.owner = THIS_MODULE,
129	rc5t583_gpio->gpio_chip.free = rc5t583_gpio_free,
130	rc5t583_gpio->gpio_chip.direction_input = rc5t583_gpio_dir_input,
131	rc5t583_gpio->gpio_chip.direction_output = rc5t583_gpio_dir_output,
132	rc5t583_gpio->gpio_chip.set = rc5t583_gpio_set,
133	rc5t583_gpio->gpio_chip.get = rc5t583_gpio_get,
134	rc5t583_gpio->gpio_chip.to_irq = rc5t583_gpio_to_irq,
135	rc5t583_gpio->gpio_chip.ngpio = RC5T583_MAX_GPIO,
136	rc5t583_gpio->gpio_chip.can_sleep = 1,
137	rc5t583_gpio->gpio_chip.dev = &pdev->dev;
138	rc5t583_gpio->gpio_chip.base = -1;
139	rc5t583_gpio->rc5t583 = rc5t583;
140
141	if (pdata && pdata->gpio_base)
142		rc5t583_gpio->gpio_chip.base = pdata->gpio_base;
143
144	platform_set_drvdata(pdev, rc5t583_gpio);
145
146	return gpiochip_add(&rc5t583_gpio->gpio_chip);
147}
148
149static int __devexit rc5t583_gpio_remove(struct platform_device *pdev)
150{
151	struct rc5t583_gpio *rc5t583_gpio = platform_get_drvdata(pdev);
152
153	return gpiochip_remove(&rc5t583_gpio->gpio_chip);
154}
155
156static struct platform_driver rc5t583_gpio_driver = {
157	.driver = {
158		.name    = "rc5t583-gpio",
159		.owner   = THIS_MODULE,
160	},
161	.probe		= rc5t583_gpio_probe,
162	.remove		= __devexit_p(rc5t583_gpio_remove),
163};
164
165static int __init rc5t583_gpio_init(void)
166{
167	return platform_driver_register(&rc5t583_gpio_driver);
168}
169subsys_initcall(rc5t583_gpio_init);
170
171static void __exit rc5t583_gpio_exit(void)
172{
173	platform_driver_unregister(&rc5t583_gpio_driver);
174}
175module_exit(rc5t583_gpio_exit);
176
177MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
178MODULE_DESCRIPTION("GPIO interface for RC5T583");
179MODULE_LICENSE("GPL v2");
180MODULE_ALIAS("platform:rc5t583-gpio");